201711000

CLG930E/936E
Hydraulic Excavator

Service Manual

Applicable type and model:CLG930E /Commins 6C8.3 (EPA Tier 2/EU Stage)

CLG936E /Commins 6C8.3 (EPA Tier 2/EU Stage)

December 30, 2017 Contents
CLG930E/936E

Contents

Safety................................................................................................................................1-1
Basic Information ............................................................................................................2-1
Structure function and maintenance .............................................................................3-1
Parameter .........................................................................................................................4-1
Adjustment and Test .......................................................................................................5-1
Fault Diagnosis................................................................................................................6-1
Removal and Installation ................................................................................................7-1
Attached drawing ............................................................................................................8-1
Contents December 30, 2017
CLG930E/936E
 1-1
December 30, 2017 Safety
CLG930E/936E

Safety

1.1 Safety Precautions ....................................................................................................1-1

Compressed Air .....................................................................................................................................1-3
High Pressure Solution ..........................................................................................................................1-3
Safe Disposal of Waste Liquid ...............................................................................................................1-3
Precautions for Accumulator Application ...............................................................................................1-4
Asbestos ................................................................................................................................................1-4
Preventing Extruding or Cut off ..............................................................................................................1-4
Prevent Burn ..........................................................................................................................................1-5
Coolant...................................................................................................................................................1-5
Oil...........................................................................................................................................................1-6
Battery....................................................................................................................................................1-6
Safeguard from Fire and Explosion .......................................................................................................1-6
Diethyl Ether ..........................................................................................................................................1-7
Pipeline, Pipe and Hose.........................................................................................................................1-7
Fire Extinguisher and First-aid Kit ..........................................................................................................1-8
Prevention of Injured by Thunder...........................................................................................................1-8
Cab Protector .........................................................................................................................................1-8
Top Safeguard and Front Safeguard ...............................................................................................1-8
Measures in Emergencies .....................................................................................................................1-9
Inner Space of Driver Cab .....................................................................................................................1-9
Precautions for Accessories ..................................................................................................................1-9

1.2 Precautions for Lifting and Matching Operations ................................................1-10

Precautions for Operating Mobile Crane..............................................................................................1-11
Precautions for Operating the Bridge Crane ........................................................................................1-11
Selection of Rope.................................................................................................................................1-12
1-2
Safety December 30, 2017
CLG930E/936E
 1-3
December 30, 2017 1.1 Safety Precautions
CLG930E/936E

1.1 Safety Precautions Do not wear casual clothes, jewelries or keep a

long hair. Because they may be drawn into the
control system or the mobile parts and lead to
Please read and be familiar with all safety severe damage or even death.
precautions to avoid the occurrence of severe
damage or even death.
Only trained and qualified persons are permitted
to operate and maintain the machine.

When for operating or maintenance, the operator

shall wear helmet and safety glasses of rigid
materials and safety shoes, face mask, and
gloves.
If you feel uncomfortable, feel sleepy after taking
medicine or have drunk, do not operate the
machine. In the case, it may cause your
misjudgment and possibility of accidents.
Please hang the labels of “Do not Operation”or
similar warnings on the starter switch or the
operation lever before the maintenance of the
machine.
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1-4
1.1 Safety Precautions December 30, 2017
CLG930E/936E

Goggles, safety glasses or mask can protect Prevent foreign matters from entering the
your eyes from the hazards of high-pressure fluid components of the system when inspecting the
during the maintenance of the battery and the opened oil tanks or water tanks. Please empty
hazards of flying debris generated during the the clothes pockets and move wrenches and
work of the engine and the operation of tools. nuts with great care before removing the cover.
Please wear the protection mask when removing
spring, elastic parts or add acid to the battery.
Please wear the safety cap and goggles when
conducting welding operations or using the
welding gun for cutting.

Learn about the gesture signals and the signal

sources at the working site and only receive the
signals from one person.
Never keep the maintenance and repair solution
in glass containers.
If you work under loud noise, please wear
appropriate hearing protection devices, such as Please observe relevant laws and regulations
earmuff or earplug, to avoid damage to hearing when disposing hazardous materials such as
due to loud noise. lubricant, fuel, coolant, solution, filter, battery and
other materials.
When using detergent, be careful.Do not use
inflammable materials as detergents, such as
diesel or gasoline. It may catch fire.

Make sure all guard plates and covers of the

machine are fastened to the machine. Please
ensure that there is no chip, greasy dirt, tool or
other foreign matters irrelevant to the machine
on the machine, especially on the instrument
Report all necessary repair work timely.
panel, channel and ladder. Put the scattered
things in place, such as the lunch boxes and Persons without permission or authorization
tools. cannot stay onto or around the machine.
It is prohibited to modify the machine without
LiuGong's consent, and LiuGong will not be
responsible for the aftermath due to modification.
 1-5
December 30, 2017 1.1 Safety Precautions
CLG930E/936E Compressed Air

Compressed Air Even if the pressured liquid is leaked as small as

a pin hole, it may also penetrate the muscles and
lead to death. If shot by the spouted high
Compressed air may cause personal injury. pressure oil, please contact a doctor and take a
When using the compressed air for cleaning, treatment immediately.
wear the mask, protection suits and shoes.
Maximum pressure of compressed air used for
cleaning should be less than 0.2MPa.

High Pressure Solution

It is forbidden to apply “fluctuation”position

to descend bucket with load. Boom Safe Disposal of Waste Liquid
descending over fast will damage the
machine.
Inappropriate disposal of waste liquid will
endanger environment and ecology. Please
Warning: Avoid being scalded by high- observe local laws and regulations when
pressure oil. When overhauling or replacing disposing the waste liquid.
the pipes of hydraulic system, check whether
the pressure of system has been released. It is necessary to contain and place the liquid
Hydraulic oil under pressure spattering on spattering during the inspection, maintenance,
skin will cause serious harm to the skin. test, adjustment and repair of machine with
vessel.
Be careful to remove the hydraulic pipelines or
joints. When the oil spouts, the released high Proper containers shall be prepared well before
pressure oil may lead to the continuous opening any fluid cavity or disassembling the
movement of the hoses. parts containing liquid.

Please wear safety goggles and leather gloves Use proper container when draining liquid. Do
when checking for leakages. Do not use bare not use the food or drink containers because
hands to check the leakage, but use plate or they may be drunk by others by mistake.
paper plate to check the leakage.
1-6
1.1 Safety Precautions December 30, 2017
Precautions for Accumulator Application CLG930E/936E

Precautions for Accumulator Asbestos

Application
If asbestos dust is sucked in, it will endanger
The accumulator with the high-pressure nitrogen your health. This product does not contain
is the dangerous article, therefore, read the asbestos and LiuGong Machinery Co. Ltd
following requirements and properly use the recommends using genuine LiuGong spare
accumulator. parts. If materials that you need to deal with
contain asbestos fiber, please observe the
The accumulator shall be checked before charge following rules:
of nitrogen. It is prohibited to charge the
● Never use compressed gas when cleaning.
accumulator with gas if the accumulator does not
have a nameplate, or the words on the Water can be used for descending the dust.
nameplate are missed so that its type can not be ● You can use the vacuum cleaner with high
identified, or if the steel seal marks are filtering properties.
incomplete or cannot be read clearly, or if there
● Do not grind the materials containing
are defects on the housing and therefore safe
use cannot be ensured. asbestos dust.
● In possible case, the machine shall be
The accumulator can only be charged with
nitrogen, and it is prohibited to charge with operated in the upstream air.
oxygen, compressed air or other inflammable ● Please observe local laws and regulations
gas to avoid explosion. when disposing asbestos.
Slowly charge the nitrogen into the accumulator ● Take a bath after contacting with asbestos.
so as to avoid the breakage of the rubber bag.
● If necessary, effective protective mask can be
The air valve of the accumulator should be used.
installed upward vertically. The accumulator shall
be stably fixed on the bracket without being
welded.
Do not drill any hole on the accumulator or carry
open fire or heat sources close to the
accumulator.
Do not conduct any welding operation on the
accumulator.
Since the accumulator is a high-pressure
container, it shall be replaced and repaired by
professional operators. Preventing Extruding or Cut off
Release the air before discarding the
accumulator. Do not have your hands, arms or any other limbs
placed between movable components. For
example, between work implement and cylinder,
between machine and work implement.
Support the equipment properly when working
under the work implement. Do not support the
work implement depending on hydraulic cylinder.
If control mechanism moves or hydraulic oil line
leaks, work implement will drop.
 1-7
December 30, 2017 1.1 Safety Precautions
CLG930E/936E Prevent Burn

If it is necessary to remove the shield during the Coolant

maintenance, then install the shield after the
maintenance.
When working, the engine coolant is at high
Revolving vane of engine has the risk of cutting temperature and has pressure, the radiator and
the fingers, so shut down the engine or keeping a all the pipes connected to the radiator contain
safety distance when repairing. hot water or vapor, if you touch them, serious
burn would occur.

Make sure there's no foreign matter in the vanes

of engine fan. Fan vanes will throw out or cut off
the tools and other things that dropped or
pushed in it.
When checking the coolant level, the engine
Unless otherwise stated, any adjustment is not shall be shut off and the filler cap shall be cooled
permitted to be performed when machine or to the extent that it can be opened by bare
engine is running. hands.
If the maintenance procedure must be performed Slowly loosen the filler cap of cooling system to
when machine is running, do not let the machine release the pressure.
stay in an unattended status. Arrange one
Coolant contains alkali which may causing injury
person to seat in the operator seat and to
and do not let it contact your skin, eyes and
prepare to shut down the engine at any time.
mouth.
Do not use twisted or worn wire rope. Wear
gloves during operation and moving.
When forcing to extrude the block pin, make sure
there is no one around. Wear safety goggles in
order to protect your eyes.
When knocking objects with hammer, please
make sure the flying debris will not hurt any
person.

Prevent Burn

After running for some time, parts of the machine

will be hot and those parts shall be inspected or
repaired after it is cooled down.
1-8
1.1 Safety Precautions December 30, 2017
Oil CLG930E/936E

Oil You shall wear safety goggles and gloves when

inspecting battery.

Hot oil and parts will cause injury to person, and

do not let the hot oil and components contact
your skin.

Under working temperature, the hydraulic oil

tank is hot and contains pressure. Safeguard from Fire and
When opening oil filler cap of hydraulic oil tank, Explosion
shut off the engineand cool the filler cap down
until it can be opened by bare hands. All fuels, most lubricants and some coolants are
Remove the tank cover slowly to release the flammables.
pressure of hydraulic oiltank so as to prevent Fuel leaking onto the hot surface or electrical
from being scalded by hot oil. elements may cause fire.
Release pressure of the system before Do not smoke when refilling or within refiling
disassembling all pipes, joints, or relevant parts. area, and in the place storing flammables.

Battery

Smog discharged from the battery may cause

explosion.
Do not smoke when inspecting the level of
battery electrolyte. Clean and tighten all the electrode connectors.
Electrolyte is a kind of acidic material, and Daily inspect the wire for looseness or wear.
please do not let your skin and eyes contact Before start, tighten the loose power supply
electrolyte. switch, and repair or replace the worn electric
wires.
Store the fuel, lubricant into containers with
relevant marks to avoid use by non-working
personnel.
Put the cleaning cloth or other combustible
materials with oil soaked into protective
container, and set it at a safe place.
 1-9
December 30, 2017 1.1 Safety Precautions
CLG930E/936E Diethyl Ether

Do not perform welding or flame cutting onto the Pipeline, Pipe and Hose
pipe containing flammable liquid. Before welding
or cutting, the operation shall be performed until
flammable liquid is cleaned completely. Do not warp or knock the high-pressure pipeline,
and do not install the abnormally warped or
Accumulated flammable materials such as fuel, broken pipes or hoses onto the machine.
lubricant or other scattered materials on the
machine shall be cleaned up. Repair the loose or damaged pipelines of fuel
and lubricant and pipes and hoses of hydraulic
Do not operate the machine near open fire. system in time. Leakage will cause fire hazard,
Make sure the battery is far away from open fire and if repair or replacement is necessary, please
and sparks, and do not smoke at the place of contact the authorized dealer by LiuGong
battery charing. Machinery Co., Ltd.

When the machine is started with a jump If following problems occur, replacement should
method, the (+) cable must be connected to be necessary.
battery (+) terminal which is connected with ● Damage or leakage of joint.
starter motor coil, and (-) of external power is
connected with (-) of the starter. If there is no ● The outer layer of hose is worn or cracked,
starter negative terminal, it shall be connected to and inner steel wires are exposed.
the engine housing. ● Partial bulge of hose.
Do not charge the frozen battery to avoid ● Hose with obvious twisting or flattening.
explosion.
● Hose guide wire is embedded into the outer
layer.
Diethyl Ether
● Misplacement of the end joints.
Make sure all clamps, guard and heat shield are
installed correctly to avoid shaking or cause
overheating by friction with other parts.
Do not use diethyl ether to start the engine When removing the connecting pipe of the
compressor, open fire is forbidden, or it will
generate toxic gas, resulting in poisoning.
Any approach which attempts to start the engine
by use of diethyl ether may cause serious
damage to engines or casualties.
1-10
1.1 Safety Precautions December 30, 2017
Fire Extinguisher and First-aid Kit CLG930E/936E

Fire Extinguisher and First-aid Kit Cab Protector

Be sure to equip fire extinguisher, carefully read Top Safeguard and Front Safeguard
its use instructions, and be sure to know how to
use it. The protectors are installed in order to prevent
The construction site must have first-aid kit in the driver from injuring by the falling or splashing
stock. Conduct regular inspection and add some objects under some special circumstances. Be
medicines if necessary. sure to close the window before hazardous work.
All personnel except the driver must be kept
You should know how to handle it when fire away hazardous zone. Please add top and front
hazard or injury occurs. guard devices as necessary.
Select some personnels' phone number (such as
doctor, first-aid center, fire station and so on) for
1
use in emergency. Post the contact number list
onto the specified locations to ensure that the
staff knows correct contact information .

1. Top guard devices

2. Front guard devices

Inspect and maintain the fire extinguisher

frequently. Follow the recommended method of
application listed on the instruction panel.

Prevention of Injured by Thunder

Never try to access the machine when there is

lightning near it.
If the thunder occurs when you sit in the cab,
please stay in cab; if you're on the ground,
please keep away from the machine.
 1-11
December 30, 2017 1.1 Safety Precautions
CLG930E/936E Measures in Emergencies

Measures in Emergencies Precautions for Accessories

When encountering emergency situation, break It should be installed and commissioned by

the window glass using the escape hammer qualified personnel; the operator should be
placed in the cab, and get out of cab. trained, and his/her operation and maintenance
shall be performed strictly according to the
operation instructions for accessories.
When installing and using the spare accessories,
please read related instructions, manuals and
informations about the accessories.
Incorrect installation or purchase of accessories
will not only cause safety issues, but also have
1
the negative effect on service life and operation
2 of the machine.
Do not use the accessories unauthorized by
LiuGong. Using unauthorized accessories will
cause safety issues, do harm on the normal
operation of machine and influence its service
life.
It is forbidden to make any refit on the
1. Escape hammer accessories without permissions; otherwise you
2. Fire extinguisher (optional) shall bear the responsibility.
LiuGong Machinery Co., Ltd will not be
Inner Space of Driver Cab responsible for the injury, accident and damage
of machine due to using unauthorized
This LiuGong machine is equipped with a cab accessories.
meeting the industry standard of: "SAE J154"
and "ISO 3411", in which provides the
requirements to the cab space.
Any refit of cab shall not occupy the specified
space. Installation of added radio, fire
extinguisher and other devices must make the
specified space kept well. Any object brought
into the cab shall not occupy the specified space.
Lunch-box or other scattered things must be
fixed. When driving on an uneven ground or
rolling over, those articles shall not endanger the
cab.

If the cab has any damage, contact your local

dealers for maintenance or replacement.
1-12
1.2 Precautions for Lifting and Matching Operations December 30, 2017
Precautions for Accessories CLG930E/936E

1.2 Precautions for Lifting When using more than 2 wire ropes for lifted
load, the larger the lifting angle of each wire
and Matching Operations roper is, the smaller the lifted load is. The figure
below shows maximum load of different lifting
1. One designated personnel sends out angle by 2 wire ropes weighting 9.8KN (1000Kg).
cooperative signal to fully keep the contacts When the lifting angle of 2 wire ropes are 0
among cooperative operating personnel. The degree, the maximum load is 19.6KN (2000 Kg);
signalman shall stay in a safe place where when the lifting angle is 120°, the maximum load
can be seen by the driver as well as can is 9.8KN (1000 Kg); If the lifting angle is 150° and
understand operating state easily, and the load is 19.6KN (2000 Kg), the wire rope
definitely send out specified signal in the requires to bear the load of 39.2KN (4000 Kg).
method in advance.
● It is forbidden to stand under the lifted load.
● It is forbidden to climb on the lifted load.
2. Check the slings and other appliances before
lifting operation.
3. Wear gloves during lifting operation. (Leather
gloves are the best)
4. Measure the weight by inspection and
guarantee the lifted load keeping steady.
5. Appropriate slings shall be used for the
weight of lifted load or lifting mode. Load may
fall down if thicker wire ropes are used for 8. A liner shall be used for avoiding being
lighter load. damaged by the wire ropes when installed on
6. Try to avoid lifting by a single wire rope. Lifted the lifted load with edge angles. For the lifted
load may rotate or fall off due to looseness. load which easily slides, an anti-skid device
Apply 2 or more wire ropes for lifting in shall be used.
symmetric mode. 9. Use genuine eyebolts and shackle, etc. to fix
eyebolts, wire ropes and iron chains, etc.
10. Hang the wire rope in the central part of hook
for lifting.
If only a single wire rope is used for lifting,
the lifted load may rotate, and swing back 11. If the wire rope is hung on the edge of hook
due to pull of the wire rope or deviate from for lifting, the rope may slide and even fall off
the lifting position, resulting in dangerous from the hook when lifting. The central part of
accident! hook has maximum intensity.
12. Do not use wire rope under the distortion
7. Lifting angle shall be below 60° in principle.
state.
Pay attention to avoiding overlarge lifting angle
between the wire rope and hook when lifting
heavy objects (above 25kg).
 1-13
December 30, 2017 1.2 Precautions for Lifting and Matching Operations
CLG930E/936E Precautions for Operating Mobile Crane

Precautions for Operating the

Bridge Crane

Heavy objects of above 25kg must be lifted

by the crane.

1. Before operation, check wire rope, brake,

clutch, controller, slide rail, over-winding
protector, residual-current circuit breaker
13. The following matters shall be noted during against electric shock, crane anti-collision
the lifting operation. device and power warning lamp to guarantee
● Roll up wire rope slowly till it is tensional. The safety.
hand may be caught easily when touching 2. Follow signal indication during lifting.
lifting tools by hands, therefore, press down
from above instead of holding them. 3. Operate the crane in a safe position.

● Stop rolling up after the wire rope is 4. Always confirm the directions of both
tensional, and confirm the condition of lifted directional display panel (east/west/south/
objects away from the ground and contact north) and the operation button.
conditions between slings and padded 5. Do not lift the load in a tilted angle or travel
objects. when the load swings.
● If the lifted load is unstable, or wire rope and 6. Do not operate lifting and lowering or
lifting chain are distorted, firstly lower the horizontal and vertical travel at the same
lifted load, and then lift again. time.
● The lifted load can not be tilted. 7. Do not use slings to drag for transport.
14. The following matters shall be noted during 8. Try to lift a little amount before lifting, and
the lowering operation. then lift after confirming it is safe.
● When lowering the lifted load, firstly stop at 9. Take moving route into consideration in
30cm above the ground or shelve, and then advance, and lift to a safe height.
lower down gently.
10. Place control switch on the position not
● Remove the slings after confirming the load affecting operation or passing.
is placed steadily.
11. Do not shake control switch forcefully after
● After the sling being arranged and cleaned, operating the crane.
put it in the designated place.
12. Remember the position of main power switch
so as to cut off the power rapidly in
Precautions for Operating Mobile emergency.
Crane

Operation and maintenance manuals of each

model shall be read carefully prior to operate the
crane safely.
1-14
1.2 Precautions for Lifting and Matching Operations December 30, 2017
Selection of Rope CLG930E/936E

13. If the crane stops operation due to power Selection of Rope

failure and other reasons, the power switch
shall be cut off. In addition, if the power
switch is disconnected due to the starting of Select the appropriate wire rope according to the
residual-current circuit breaker against weights of lifted load, referring to following table.
electric shock, confirm whether relevant
Wire rope
machinery of the switch is in operation states
(Wire rope comply with standard "Z" without
before contacting again.
plating)
14. Stop the operation when finding out any (JIS G35256 No. 6×37-Class A)
obstacle around the machine.
Diameter of
15. After the operation being completed, drive Permissible load
wire rope
the crane to the designated position, and lift
mm kN t
the hook to the height of 2m from the ground.
Do not hang slings on the hook when 10 8.8 0.9
parking. 12 12.7 1.3
14 17.3 1.7
16 22.6 2.3
18 28.6 2.9
20 35.3 3.6
25 55.3 5.6
30 79.6 8.1
40 141.6 14.4
50 221.6 22.6
60 318.3 32.4

Permissible load value is 1/6 of breaking load

of used wire rope (safety coefficient is 6).
 2-1
December 30, 2017 Basic Information
CLG930E/936E

Basic Information

2.1 How to Read the Manual ...........................................................................................2-1

2.2 Marking of Revised Version .....................................................................................2-2
2.3 General Torque Specifications.................................................................................2-3
2.4 Unit Conversion Table ..............................................................................................2-8
2.5 Cable Identification Methods....................................................................................2-9
2.6 Coating Materials ....................................................................................................2-11
2.7 Weight Table ............................................................................................................2-12
2.8 Specifications for Oil Application ..........................................................................2-13
2-2
Basic Information December 30, 2017
CLG930E/936E
 2-3
December 30, 2017 2.1 How to Read the Manual
CLG930E/936E

2.1 How to Read the Manual User's Guidance

1. Because the influences to the machine from

Composition of service manual area or processing are different, it shall
confirm which machine is applicable, and
The Manual is used by green hands or technical what work implements it has.
service personnel with rich experience for
reference. This manual includes all technical 2. Some accessories and optional parts in the
information required by workshop maintenance, Manual may not be transported to relevant
and for easy understanding and convenient areas, and consult your local LiuGong dealer
reading, it is divided into technical guide and if required.
workshop guide, for the purpose of reading the 3. The materials and technical specifications in
relevant chapters and sections as required. the Manual are changed with variation of
products, and all information, diagrams and
1. Technical Guide specifications in the Manual are the latest
product information obtained at the time of
1. Safety publication. LiuGong reserves the right to
2. ForewordG make modification without any notice. If it
needs to obtain the latest technical
3. Structural function and maintenance information, please consult the dealer of
standards LiuGong in local area or Service Department
4. Test and Adjustment of LiuGong Excavator Marketing Co., Ltd.

5. Fault Diagnosis

2. Workshop Guide

1. Disassembly and assembly

2. Schematic diagrams of electrical system, air
conditioning system and hydraulic system

Other Reference Manuals

For basic information of structure, operation and

maintenance of the machine, refer to the
following three manuals, which are distributed to
the users in the form of vehicle accessory.
1. Part drawing
2. Operation and maintenance manual
3. Parts manual for Cummins engine
2-4
2.2 Marking of Revised Version December 30, 2017
CLG930E/936E

2.2 Marking of Revised Version

The meaning of version number for service manual of LiuGong is as follows:

Second version

Publication month

Publication year

When the version is revised, the year and month will embody revision date of the version, and the last
numbers will reflect revision times of the Manual. For example, 001 represents the first revision, 002
represents the second revision, and so on.
 2-5
December 30, 2017 2.3 General Torque Specifications
CLG930E/936E

2.3 General Torque Specifications

Bolts involved in this machine shall be tightened in accordance with the torque requirements specified in
the following table, unless special declaration.
Table 1 CLG 930E excavator bolt torque chart

Bolt Wrench size Torque

No. Description
specification (mm) N.m lbf·ft
Captive bolt of the engine shock M24-10.9 36 900 663.8
1
absorber M20-10.9 30 550 405.6
115 (Cylinder 84.8 (Cylinder
block) block)
2 Captive bolt of engine mounting M12-10.9 18 50 (Aluminum 36.9 (Aluminum
flywheel flywheel
housing) housing)
3 Bolt on flywheel housing M10-10.9 16 65 47.9
4 Captive bolt of water tank bracket M16-10.9 24 305 224.9
5 Captive bolt of fuel tank M16-10.9 24 305 224.9
6 Captive bolt of hydraulic oil tank M16-10.9 24 305 224.9
7 Captive bolt of pump M20-10.9 17 Inner hexagon 600 442.5
8 Captive bolt of main control valve M12-10.9 18 120 88.5
9 Captive bolt of slewing reducer M24-10.9 36 1020 752.3
10 Captive bolt of swing motor M20-10.9 17 Inner hexagon 430 317.1
11 Captive bolt of battery M10-8.8 16 52 38.4
12 Captive bolt of cab M20-10.9 30 600 442.5
Captive bolt of revolving frame and
13 M24-10.9 36 1020 752.3
swing bearing
Captive bolt of underframe swivel
14 M24-10.9 36 1020 752.3
bearing
15 Captive bolt of the travel reducer M24-10.9 36 1020 752.3
16 Captive bolt of sprocket M20-10.9 30 600 442.5
17 Captive bolt of carrier roller M18-10.9 27 415 306.1
18 Captive bolt of track roller M20-10.9 30 600 442.5
19 Captive bolt of track shoe M24-12.9 36 800 590
20 Captive bolt of track guard M22-10.9 34 800 590
21 Mounting bolt of counterweight M42-10.9 65 4600 3392.5
2-6
2.3 General Torque Specifications December 30, 2017
CLG930E/936E

Table 2 CLG 936E excavator bolt torque chart

Bolt Wrench size Torque

No. Description
specification (mm) N.m lbf·ft
Captive bolt of the engine shock
1 M24-10.9 36 900 663.8
absorber
115 (Cylinder 84.8 (Cylinder
block) block)
2 Captive bolt of engine mounting M12-10.9 18 50 (Aluminum 36.7 (Aluminum
flywheel flywheel
housing) housing)
3 Bolt on flywheel housing M10-10.9 16 30 22.1
4 Captive bolt of water tank bracket M16-10.9 24 305 224.9
5 Captive bolt of fuel tank M16-10.9 24 305 224.9
6 Captive bolt of hydraulic oil tank M16-10.9 24 305 224.9
7 Captive bolt of pump M20-10.9 17Inner hexagon 600 442.5
8 Captive bolt of main control valve M12-10.9 18 120 88.5
9 Captive bolt of slewing reducer M24-10.9 36 1020 752.3
10 Captive bolt of swing motor M20-10.9 17Inner hexagon 600 442.5
11 Captive bolt of battery M10-8.8 16 52 38.4
12 Captive bolt of cab M20-10.9 30 600 442.5
Captive bolt of revolving frame and swing
13 M24-10.9 36 800 590
bearing
Captive bolt of underframe swivel
14 M24-10.9 36 800 590
bearing
15 Captive bolt of the travel reducer M24-10.9 36 800 590
16 Captive bolt of sprocket M20-10.9 30 600 442.5
17 Captive bolt of carrier roller M18-10.9 27 415 306.1
18 Captive bolt of track roller M20-10.9 30 600 442.5
19 Captive bolt of track shoe M24-12.9 36 800 590
20 Captive bolt of track guard M24-10.9 36 1020 752.3
21 Mounting bolt of counterweight M42-10.9 65 4600 3392.5
 2-7
December 30, 2017 2.3 General Torque Specifications
CLG930E/936E

Tightening Torque of 24°Cone With O-ring Sealed Pipe Fittings

Hose inner Tightening torque

Series Thread size diameter
mm N.m kgf.m
M12×1.5 5 16±1 1.6±0.1
M14×1.5 6.3 16±1 1.6±0.1
M16×1.5 8 26±2 2.7±0.2
M18×1.5 10 37±2 3.8±0.2
M22×1.5 12.5 47±2 4.8±0.2
Light-type
M26×1.5 16 89±4 9.1±0.4
M30×2 19 116±5 11.8±0.5
M36×2 25 137±6 14.0±0.6
M45×2 31.5 226±11 23.1±1.1
M52×2 38 347±16 35.4±1.6
M14X1.5 5 26±2 2.7±0.2
M16X1.5 6.3 42±2 4.3±0.2
M18X1.5 6.3 53±2 5.4±0.2
M20X1.5 8 63±3 6.4±0.3
M22X1.5 10 79±4 8.1±0.4
Heavy-type
M24X1.5 12.5 84±4 8.6±0.4
M30X2 16 126±6 12.9±0.6
M36X2 19 179±8 18.3±0.8
M42X2 25 263±12 26.8±1.2
M52X2 31.5 368±17 37.6±1.7
2-8
2.3 General Torque Specifications December 30, 2017
CLG930E/936E

Tightening Torque of Flange Seal Pipe Joint Bolt

Bolt Tightening torque

Series Bolt performance
level N.m kgf.m

M8 25.2±1.2 2.57±0.12

M10 52.5±2.5 5.36±0.26

8.8
M12 96.6±4.6 9.86±0.47

M16 220±10 22.4±1.02

Light-type
M8 33.6±1.6 3.43±0.16

M10 73.5±3.5 7.50±0.36

10.9
M12 136±6 13.88±0.61

M16 310±15 31.63±1.53

M8 25.2±1.2 2.57±0.12

M10 52.5±2.5 5.36±0.26

M12 8.8 96.6±4.6 9.86±0.47

M16 220±10 22.45±1.02

M20 420±20 42.86±2.0

Heavy-type
M8 33.6±1.6 3.43±0.16

M10 73.5±3.5 7.5±0.36

M12 10.9 136±6 13.88±0.6

M16 310±15 31.63±1.53

M20 577±27 58.88±2.76

 2-9
December 30, 2017 2.3 General Torque Specifications
CLG930E/936E

Tightening Torque of Thread Angle Type Sealed Hose Connector

Material of
Carbon steel and alloy steel Aluminum product
fastenings
Tightening torque Tightening torque
Thread size
N.m kgf.m N.m kgf.m
G1/8 8.75±1.25 0.90±0.12 / /
G1/4 36±2 3.67±0.2 29.3±2.2 3.0±0.2
G3/8 73.5±4.5 7.5±0.46 49±3 5.0±0.3
G1/2 110±10 11.2±1.0 55±5 5.6±0.5
G3/4 165±15 16.8±1.5 74±4 7.5±0.4
G1 225±25 23.0±2.55 / /
G1-1/4 275±25 28.0±2.55 / /
G1-1/2 285±15 29.1±1.5 / /

Connector Tightening Torque

Tightening torque
Thread size
N.m kgf.m
M12 24±2 2.4±0.2

M14 30±2 3.1±0.2

M16 30±2 3.1±0.2

M18 30±2 3.1±0.2

2-10
2.4 Unit Conversion Table December 30, 2017
CLG930E/936E

2.4 Unit Conversion Table

The Manual uses ISO International System of Units, and ISO international units are converted into
British units as shown in following figure:

Parameters Metric unit British unit Multiple

mm In 0.03937
Length
mm ft 0.003281
L US gal 0.2642
Capacity L US qt 1.057
m³ 3 1.308
Yd
Weight kg lb 2.205
N kgf 0.10197
Intensity
N lbf 0.2248
Nm kgf·m 0.1097
Torque
Nm lbf·ft 0.7375
MPa 3 10.197
kgf/cm
Pressure
MPa psi 145.0
kW PS 1.360
Power
kW HP 1.341
Temperature °C °F °C×1.8+32
km/h mph 0.6214
Speed
min-1 rpm 1.0
L/min US gpm 0.2642
Flow
mL/rev cc/rev 1.0
 2-11
December 30, 2017 2.5 Cable Identification Methods
CLG930E/936E

2.5 Cable Identification Methods

The wire in circuit diagram is marked in combination with wire No., wire categories, color abbreviation
codes and wire gauge for maintenance. For example:

Indicates heat-resistant, lower-voltage wire for vehicles, red, with the number of 108
and a diameter of 50.0mm2.

Wire gauge (Note: the ones with no marked wire gauge are all 0.85mm2)

Color abbreviation code

Wire categories

Wire No.

Wire No.

Wire No. is digital code for marking wire with three Arabic numbers in accordance with certain rules.

Wire Categories

The wire categories selected for engineering machinery are AEX, AV, AVS, AVSS, and QVR in general.
For applicable range of ambient temperature of various wires, see following table.

No. Wire type Wire name Description Heat resistance

1 QVR Low-voltage wire for road vehicles Cooper core PVC-insulated ≤70°C
Thin-wall insulated low-voltage wire The thickness of insulation layer
2 AVSS ≤80°C
for vehicles is 0.30~0.40mm
Thin-wall insulated low-voltage wire The thickness of insulation layer
3 AVS ≤80°C
for vehicles is 0.50~0.70mm
Insulated low voltage wire for The thickness of insulation layer
4 AV ≤80°C
vehicles is 0.60~2.0mm
Heat-resisting low voltage wire for Heat resistance and cross-
5 AEX ≤110°C
vehicles linking polyethylene
2-12
2.5 Cable Identification Methods December 30, 2017
CLG930E/936E

Color Abbreviation Codes

Color English Abbreviation Color English Abbreviation

Black BLACK BK Blue BLUE BU
Grey GREY GY Green GREEN GN
Red RED RD Yellow YELLOW YL
Brown BROWN BR Pink PINK PK
Violet VIOLET VT Orange ORANGE OR
White WHITE WH Light blue LIGHT BLUE LTBU
Red/green RED/GREEN RD/GN Yellow/blue YELLOW/BLUE YL/BU

Remark: the code composed of two colors indicates double-color wire, for example: "RD/GN" indicates
red-green wire.

Wire Specifications

Allowable current and voltage drop of AV wire, and approximate performances of AVS, AVSS and QVR
shall be executed uniformly according to following table.

Ambient
30°C 40°C 50°C 60°C 70°C
temperature
Allowable
current/voltage A mV/m A mV/m A mV/m A mV/m A mV/m
drop
0.85 18 463 16 412 14 360 11 283 8 206
1.25 23 407 21 372 18 319 14 248 10 177
2 31 338 28 305 24 262 20 218 14 153
3 42 291 38 263 33 228 27 187 19 132
5 57 248 51 222 44 192 36 157 25 109
8 74 213 66 190 57 164 47 135 33 95
Nominal 15 103 176 92 157 80 137 65 111 46 79
sectional
area (mm2) 20 135 148 121 133 105 116 85 94 60 66
30 188 121 168 108 146 94 119 77 84 54
40 210 112 188 110 163 87 133 71 94 50
50 246 103 220 92 190 80 155 65 110 46
60 272 97 243 87 211 75 172 62 121 43
85 335 90 300 80 260 70 212 57 150 40
100 399 83 356 74 309 65 252 53 178 37
 2-13
December 30, 2017 2.6 Coating Materials
CLG930E/936E

Circuit Type and Color Abbreviation Code

For general corresponding rules between circuit type and wire color, see the following table.
Circuit type Color abbreviation codes
Power line OR, RD
Signal line WH
Grounding BK, GY
Communication line RD/GN, YL/BU

2.6 Coating Materials

Name Specifications Main features and purposes

Oxygen-weary type thread lock •Features: anaerobic and fast air drying.
1277
sealant •Purposes: used for parts not frequently removed
Thread locker 1243 Used for removable parts (speed sensor in general)
•Features: rust protection for a long time.
LONG#2 light
Long-term anti-rust agent •Purposes: used for mounting face of main pump, sensor,
yellow
hydraulic fitting, etc.
Molybdenum-disulfide lithium-base Lubrications for swing bearing and pin shaft of work
2#
grease implement
• Features: strong ability of cleaning
High efficient detergent 1755 •Purposes: used for main pump, swing motor and travel
motor
•Features: heat absorption and vaporization,
Refrigerant R134a
•Purposes: used for fluorine filling of air conditioner, etc.
•Feature: it has features of high-temperature resistance,
self-lubrication and medium resistance and is used for
medium (sealing oil, air, vapor, water) pipeline cone/taper
Anaerobic pipe thread sealant 1567
thread
•Purposes: used for 0water temperature sensor and engine
oil pressure sensor
Cleaning agent for
HD-10 Used for cleaning oil pipe connectors, etc.
electromechanical equipment
Diesel engine sealant 1515 Used for mounting face of diesel engine flange
Used for waterproof of starter motor and assembling
Polyurethane sealant 1924
clearance
Mobilux EP None Used for rust protection of rear cover hinge
2-14
2.7 Weight Table December 30, 2017
CLG930E/936E

2.7 Weight Table

The following table indicates the reference value of the weight of each component. When the hoisting
equipment is used, please refer to the following table to select the sling.
Weight (kg)
Components
CLG930E CLG936E
Engine assembly (excluding coolant and engine oil) 743 743
Engine (excluding coolant and engine oil) 617 617
Hydraulic pump 130 186
Radiator assembly (excluding coolant, engine oil and fuel) 220 260
Hydraulic oil tank (without hydraulic oil) 235 253
Fuel tank (without fuel) 273 288
Revolving frame 2644 2942
Cab 385 665
Seat in Cab 38.6 31
Counterweight 5500 6500
Main control valve 230 230
Swing motor & reduction gear 424 424
Travel motor & reduction gear 399 399
Center joint 57 57
Boom 2134 2530
Arm 1086 1230
Boom cylinder assembly (single) 265 (integrated steel pipe) 294.7 (integrated steel pipe)
Arm cylinder assembly 345 (integrated steel pipe) 481 (integrated steel pipe)
Bucket cylinder assembly 250 (integrated steel pipe) 285 (integrated steel pipe)
Track assembly (single side) 1869.2 2108
Track frame assembly 4059 4192
Guide wheel assembly 242 242
Swing bearing 445 504
Idler tensioner 235 235
Carrier roller 35 35
Sprocket 80 80
Track roller 51.5 66
 2-15
December 30, 2017 2.8 Specifications for Oil Application
CLG930E/936E

2.8 Specifications for Oil Application

Time Interval of Oil Change and Approximate Filling Volume

Oil change interval Approximate filling volume (L)

Category
(working hours) CLG930E CLG936E
Engine oil 250 26.5 26.5
Slewing reducer gear oil 1000 10.5 10.5
Gear oil of travel reduction gear 1000 (9.5L×2) (9.5L×2)
Fuel tank 195 Fuel tank 240
Hydraulic oil 2000
(system 360 ) (system 450 )
Fuel 520 620
Cooling System 2000 35
2-16
2.8 Specifications for Oil Application December 30, 2017
CLG930E/936E

Technical Specification for Oils

Application
Oil category Oil specifications Ambient temperature
locations
Bucket, swing bearing of Molybdenum-disulfide lithium-base
-20~40°C(-4~104°F)
Lubricant arm and boom, and grease 2# ★a
swiveling gear EP2 or RO2 -20~40°C(-4~104°F)
5W-40(API CH-4) -35~40°C(-31~104°F)
Engine crankcase, fuel
Diesel engine oil injection pump and 10W-30(API CH-4) -30~30°C(-22~86°F)
regulator -25~40°C(-13~104°F)
15W-40(API CH-4) ★
0# ★ Above 4°C (above 39.2°F)
-10# Above -5°C (above 23°F)
Diesel fuel -20# Above -14°C (above 6.8°F)
-30# Above -29°C (above -20.2°F)
-50# Above -44°C (above -47.2°F)
Anti-freeze (100% original liquid) and
Anti-freeze -30~40°C(-22~104°F)
water with proportion of 42:58
Swing reduction gear SAE85W-140(API GL-4) -20~45°C(-4~113°F)
Gear oil
Travel reduction gear SAE80W-90 (API GL-4) -20~45°C(-4~113°F)
ISO VG 32 -20~20°C(-4~68°F)
Hydraulic oil Hydraulic system ISO VG 46 ★ -20~40°C(-4~104°F)
ISO VG 68 -10~40°C(14~104°F)

a. The oil marked with ★ is the oil filled when the machine is transported out of the factory

1. The oil of the same specification but of different brands can't be used together. If another
brand of oil must be used, please clean the system first.
2. The lubricant should be changed on time. Even though the oil is very clean, yet it may
deteriorate if it is placed for a long time.
3. The selection of fuel should depend on the lowest temperature of the place where the machine
is used.
4. Except oil specifications in above table, when using the oil purchased in the market, please
contact the LiuGong dealers.
 3-1
December 30, 2017 Structure function and maintenance
CLG930E/936E

Structure function and maintenance

3.1 Power System ............................................................................................................3-3

3.1.2 Water Radiator, Hydraulic Oil Radiator, Inter-cooler and Fuel Radiator .....................................3-3

3.2 Track Travel System..................................................................................................3-5

3.2.1Travel Frame and Tensioner..........................................................................................................3-5
3.2.2 Idler ...............................................................................................................................................3-6
3.2.3 Carrier Roller.................................................................................................................................3-8
3.2.4 Track roller ....................................................................................................................................3-9
3.2.5 Sprocket ......................................................................................................................................3-11
3.2.6 Track ...........................................................................................................................................3-12
3.2.7 Swing Bearing .............................................................................................................................3-13

3.3 Hydraulic System ....................................................................................................3-14

3.3.1 Layout Diagram of Hydraulic Unit .............................................................................................3-14
3.3.2 Hydraulic Element .......................................................................................................................3-16
3.3.2.1 Main Pump Assembly ........................................................................................................3-16
3.3.2.2 Main Control Valve.............................................................................................................3-30
3.3.2.3 Center Joint........................................................................................................................3-65
3.3.2.4 Explosion Relief Valve .......................................................................................................3-67
3.3.2.5 Hand Pilot Valve.................................................................................................................3-68
3.3.2.6 Travel Pilot Valve ..............................................................................................................3-72
3.3.2.7 Four-step Solenoid Valve .................................................................................................3-75
3.3.2.8 Travel Motor & Reduction Gear .........................................................................................3-77
3.3.2.9 Swing Motor and Reduction Gear ......................................................................................3-93
3.3.2.10 Oil Cylinder.....................................................................................................................3-104
3.3.2.11 Hydraulic Oil Tank Assembly .........................................................................................3-107
3.3.2.12 PTO Pump .....................................................................................................................3-111
3.3.3 Hydraulic Principle ....................................................................................................................3-114
3.3.3.1 Main Hydraulic Circuit ......................................................................................................3-114
3.3.3.2 Pilot Circuit .......................................................................................................................3-118
3.3.3.3 Negative Flow Control Circuit (with the Control Spool in the Neutral)..............................3-120
3.3.3.4 Negative Flow Control Circuit (with the Control Spool Moving) .......................................3-122
3.3.3.5 Boom Rising Working Circuit ...........................................................................................3-124
3.3.3.6 Boom Descending Working Circuit ..................................................................................3-126
3-2
Structure function and maintenance December 30, 2017
CLG930E/936E

3.3.3.7 Arm Stretching Working Circuit ........................................................................................3-128

3.3.3.8 Arm Retraction Working Circuit (with Regeneration) .......................................................3-130
3.3.3.9 Arm Retraction Working Circuit (with no Regeneration) ..................................................3-132
3.3.3.10 Bucket Retraction Working Circuit .................................................................................3-134
3.3.3.11 Bucket Stretching Working Circuit..................................................................................3-136
3.3.3.12 Left Swing Working Circuit .............................................................................................3-138
3.3.3.13 Swing Priority Circuit ......................................................................................................3-140
3.3.3.14 Right Swing Working Circuit...........................................................................................3-142
3.3.3.15 Travel Forward Working Circuit (Fast) ...........................................................................3-144
3.3.3.16 Travel Backward Working Circuit (Slow) ........................................................................3-148
3.3.3.17 Bilateral Travel and Boom Rising Compound Operating Circuit ....................................3-152

3.4 Work Implement.....................................................................................................3-154

3.4.1 Maintenance References of Main Parts ....................................................................................3-154
3.4.2 Maintenance References of Arm Part ......................................................................................3-157
3.4.3 Maintenance References of Bucket Part ..................................................................................3-159

3.5 A/C System.............................................................................................................3-161

3.5.1 Layout Diagram of A/C Pipeline ...............................................................................................3-161

3.6 Electrical System...................................................................................................3-162

3.6.1 Engine Control ..........................................................................................................................3-162
3.6.2 Display System .........................................................................................................................3-163
3.6.2.1 Display .............................................................................................................................3-164
3.6.2.2 LCD Part of Display..........................................................................................................3-166
3.6.2.3 Display Key Panel ............................................................................................................3-170
3.6.2.4 Software Introduction .......................................................................................................3-172
3.6.2.5 User Mode........................................................................................................................3-173
3.6.3 Electrical Control System ..........................................................................................................3-177
3.6.3.1 Work Mode.......................................................................................................................3-177
3.6.3.2 Automatic Idling Function.................................................................................................3-178
3.6.3.3 Transient Power Boosting Function .................................................................................3-179
3.6.3.4 Overheating Protection Function......................................................................................3-180
3.6.3.5 Traveling Speed Control Function....................................................................................3-181
3.6.3.6 Various ComponentS .......................................................................................................3-182
3.6.4 Descriptions of Partial Circuits ..................................................................................................3-190
3.6.4.1 Travel Two-Speed Circuit.................................................................................................3-190
 3-3
December 30, 2017 Structure function and maintenance
CLG930E/936E

3.6.4.2 Transient Pressure Boosting Circuit.................................................................................3-191

3.6.4.3 Start Circuit ......................................................................................................................3-192
3.6.4.4 Trenching Function Circuit ...............................................................................................3-194
3.6.4.5 Grader Function Circuit ....................................................................................................3-195
3.6.4.6 Charge Circuit ..................................................................................................................3-196
3.6.4.7 Working Circuit of the Pump Proportional Solenoid Valve ...............................................3-197
3-4
Structure function and maintenance December 30, 2017
CLG930E/936E
 3-3
December 30, 2017 3.1 Power System
CLG930E/936E 3.1.2 Water Radiator, Hydraulic Oil Radiator, Inter-cooler and Fuel Radiator

3.1 Power System 1. Left front engine

mounting
6. Right front engine
mounting
2. Fan side engine shock 7. Right rear engine
absorber mounting
3.1.1 Diesel Engine Related Parts 3. Left rear engine 8. Coupling
mounting 9. Main pump flange
4. Flywheel housing side
engine shock absorber
5. Muffler

3.1.2 Water Radiator, Hydraulic Oil

Radiator, Inter-cooler and Fuel
Radiator
5

2
3
1
1
2 3

7
9
3-4
3.1 Power System December 30, 2017
3.1.2 Water Radiator, Hydraulic Oil Radiator, Inter-cooler and Fuel Radiator CLG930E/936E

5
6

8
9

10

11

1. Hydraulic oil radiator 7. Water radiator inlet pipe

2. Water radiator 8. Refill water pipe
3. Intercooler 9. Water radiator outlet
4. Tank receiver pipe
5. Degassing pipe 10.Fan
6. Fan shield 11.Shroud
 3-5
December 30, 2017 3.2 Track Travel System
CLG930E/936E 3.2.1Travel Frame and Tensioner

3.2 Track Travel System

3.2.1Travel Frame and Tensioner

1. Idler 5. Track roller

2. Travel frame 6. Track
3. Carrier roller 7. Tensioner
4. Sprocket

Judgment standards
No. Item Measures
Standard size Allowable limit
Installation Installation Installation Installation
Free length
7 Tensioner length load length load Replacement
- 995mm 190.12KN - -
3-6
3.2 Track Travel System December 30, 2017
3.2.2 Idler CLG930E/936E

Judgment standards

No. Item Standard Maintenance Measures

Tolerance
size limit
(Unit: mm)
(Unit: mm) (Unit: mm)
Travel +4
132 138 Overlaying repair
Vertical width of frame 0
8
idler guiding plate
0 Overlaying repair or
Idler 130 127
-1 replacement
Travel +4
262 268 Overlaying repair
Horizontal width of frame 0
9
idler guiding plate 0 Overlaying repair or
Idler 260 257
-1 replacement

3.2.2 Idler
 3-7
December 30, 2017 3.2 Track Travel System
CLG930E/936E 3.2.2 Idler

No. Check items Standard (unit: mm) Measures

Standard size Maintenance limit
1 Outer diameter of bulge
640 ——
Outer diameter of wheel
2 590 578
surface
Thickness of wheel Overlaying
3 19
surface or
Difference of wheel replacement
4 25 31
surfaces
5 Overall width 203 ——
6 Width of wheel surface 50.5 ——
Standard Tolerance Standard Limit
Clearance between shaft size Shaft Hole clearance clearance
7
and bushing 0 +0.35
90 0.08-0.4 1.5
-0.05 -0.08
Standard Tolerance Standard Interference
Interference between size Shaft Hole interference limit Replace
8 bushing
idler and bushing +0.18 +0.06
105 0.08-0.18 ——
+0.14 0
Clearance between Standard value Clearance limit
bushing and neck strap
9
(the sum of clearances 0.5-1.0 ——
on both sides)
3-8
3.2 Track Travel System December 30, 2017
3.2.3 Carrier Roller CLG930E/936E

3.2.3 Carrier Roller

No. Check items Standard Measures

Standard size Maintenance limit
1 Outer diameter of bulge
188 ——
Outer diameter of wheel
2 160 106
surface
3 Width of wheel surface 49.5 ——
Thickness of wheel
4 22 15
surface
5 Bulge width 95 ——
Standard Tolerance Standard Limit
Replacement
Clearance between shaft size Shaft Hole clearance clearance
6
and bushing -0.250 +0.099
58 0.218-0.369 ——
-0.270 -0.032
Standard Tolerance Standard Interference
Interference between size Shaft Hole interference limit
7
carrier roller and bushing +0.117 +0
66 0.087-0.158 ——
+0.087 -0.040
Axial clearance of carrier Standard value Clearance limit
8
roller 0.60-0.80 ——
 3-9
December 30, 2017 3.2 Track Travel System
CLG930E/936E 3.2.4 Track roller

3.2.4 Track roller

Model CLG930E Unit(s) mm

No. Check items Standard Measures
Standard size Repair size
1 Outer diameter of flange
216 ——
Outer diameter of wheel
2 180 168
surface
Thickness of wheel Replacement
3 52.5 46.5
surface
4 Overall width 270 ——
5 Width of wheel surface 43.5 ——
6 Width of flange 24 ——
Standard Tolerance Standard Clearance
Clearance between shaft size Shaft Hole clearance limit
7
and bushing -0.250 +0.186
65 0.186-0.536 1.5
-0.350 -0.064 Replace
Standard Tolerance Standard Interference bushing
Interference between size Shaft Hole interference limit
8
track roller and bushing +0.108 +0.006
72 0.014-0144 ——
+0.008 -0.036
3-10
3.2 Track Travel System December 30, 2017
3.2.4 Track roller CLG930E/936E

Clearance between Standard value Clearance limit

bushing and neck strap Replacemen
9
(the sum of clearances 0.5-1.0 —— t
on both sides)

Model CLG936E Unit(s) mm

No. Check items Standard Measures
Standard size Maintenance limit
1 Outer diameter of flange
216 ——
Outer diameter of wheel
2 180 168
surface
Replacemen
Thickness of wheel
3 54 48 t
surface
4 Overall width 250 ——
5 Width of wheel surface 49 ——
6 Width of flange 27 ——
Standard Tolerance Standard Clearance
Clearance between size Shaft Hole clearance limit
7
shaft and bushing -0.250 +0.186
85 0.186-0.536 1.5
-0.350 -0.064
Standard Tolerance Standard Interference Replace
Interference between size Shaft Hole interference limit bushing
8
track roller and bushing +0.108 +0.006
95 0.014-0144 ——
+0.008 -0.036
Clearance between Standard value Clearance limit
bushing and neck strap
9
(the sum of clearances 0.3-1.2 ——
on both sides)
 3-11
December 30, 2017 3.2 Track Travel System
CLG930E/936E 3.2.5 Sprocket

3.2.5 Sprocket

No. Check items Standard (unit: mm) Measures

1 Wear on sprocket teeth Maintenance limit
Standard size Repair limit Replacement
2 Width of sprocket teeth
90 87
3-12
3.2 Track Travel System December 30, 2017
3.2.6 Track CLG930E/936E

3.2.6 Track

No. Check items Standard (unit: mm) Measures

Standard size Maintenance limit
1 Track pitch
215.9 212.9
2 Height of track link 124 115
Height of track shoe Overlaying or
3 30 20
grouser replacement
4 24
5 Length of track shoe top 18
6 18
 3-13
December 30, 2017 3.2 Track Travel System
CLG930E/936E 3.2.7 Swing Bearing

3.2.7 Swing Bearing

No. Check items Standard (unit: mm) Measures

Axial clearance of bearing Standard clearance Maintenance limit
1 (When installed onto the Replacement
chassis) 0.5-1.6 3.2
3-14
3.3 Hydraulic System December 30, 2017
3.3.1 Layout Diagram of Hydraulic Unit CLG930E/936E

3.3 Hydraulic System

3.3.1 Layout Diagram of Hydraulic Unit

1. Bucket cylinder 2. Arm cylinder 3. Boom cylinder

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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.1 Layout Diagram of Hydraulic Unit

8 9 10 11 12 13

14

15

16

4. Swing motor & reduction 9. Return oil filter 14.Right hand pilot valve T1: oil return of
gear 10.Main control valve 15.Left hand pilot valve electromagnetic valve
5. Right travel motor & 11.Left travel motor & 16.Travel pilot valve A1: Pilot unlock
reduction gear reduction gear P1: oil inlet of A2: Travel shift
6. Main pump 12.Four-step solenoid valve electromagnetic valve A3: Arm second speed
7. Accumulator 13.Center joint A7: Transient power
8. Breather valve boosting
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3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

3.3.2 Hydraulic Element

3.3.2.1 Main Pump Assembly

Structure and Function of Main Pump Assembly

1. Drive shaft Pi1-P1 pump pilot oil port B1- Main oil pump suction port
2. Minimum flow adjusting nut Pi2-P2 pump pilot oil port B3- Pilot pump suction port
3. Main pump regulator Psv - Main pump servo port Dr - Housing return oil
4. Electric proportional pressure- a1, a2, a3, a4- Pressure test port
reducing valve
5. Max.flow adjustment

Main pump assembly is composed of the main pump (pumps P1 and P2) and a pilot pump (pump P3).
The main fuel pump is a double variable plunger pump and provides high pressure oil for the main oil
circuit so that to supply pressure oil to hydraulic element such as main oil circuit. The pilot pump is a
constant gear pump and supplies oil for the pilot system and the main pump control system.
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

1. Main Fuel Pump (pumps P1 and P2)

Main oil pump specifications

930E 936E
Displacement cm3/rev
160×2 140×2
Pressure Rated 34.3
MPa Max. 37.3
Rotate speed Rated 1900
r/min Max. 2000
Weight kg 130 185
Category Anti-wear hydraulic oil
Temperature range -20~+95°C
Hydraulic oil Viscosity range 10~200cSt(mm2/s)
Recommended Oil-return line Nominal size 10mm
strainer Suction line 80 ~ 150 mesh filter screen

Structure and Working Principle of Main Pump

The main pump is directly driven by the engine via a coupling, and the pilot gear pump is connected
behind the pump P2 in series, is indirectly driven by the drive shaft and rotates at the same speed to the
main pump during working.

1. P2 Pump regulator 3. Shaft 5. P2 pump

2. P1 Pump regulator 4. P1 pump
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3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

Parts list of main oil pump

532 Spool 251 Swashplate stand 724 O-ring
534 Limit screw plug 261 End cover 725 O-ring
11 Plunger group 271 Pump housing 728 O-ring
13 Right cylinder block assembly 311 Housing cover 732 O-ring
14 Left cylinder block assembly 312 Housing cover 774 Rectangular seal
30 Swashplate component 401 Bolt 789 Snap ring
530 Pin assembly 402 Hexagon socket bolt 792 Snap ring
111 Drive shaft 406 Bolt 808 Nut
113 Drive shaft 466 Screw plug 824 snap ring
114 Coupling 468 Screw plug 885 Pin
123 Cylindrical roller bearing 490 Screw plug 886 Pin
124 Needle bearing 492 Screw plug 901 Screw
127 Thrust ring 535 Limit screw plug 953 Bolt
130 Turbocharger 702 O-ring 954 Bolt
153 Pressure plate 706 O-ring 956 Hexagon socket bolt
156 Bushing 710 O-ring 981 Nameplate
157 Cylinder block spring 717 O-ring 983 Pin
211 Swashplate 719 O-ring

The main pump is composed of two plunger The rotation mechanism consists of driving shaft
pumps, namely pump P1 and pump P2, which (111·113), cylinder block (141), plunger, piston
are connected by a coupling (114). The rotation shoes (151·152), return plate (153), spherical
of the motor is delivered to the drive shaft (111) bushing (156), return spring (157). The driving
at the front to simultaneously drive the two shaft is supported with the bearings (123, 124) at
pumps. The oil suction port and oil discharge both ends. The piston shoe is rived on the head
port are converged at the cover (namely valve of plunger in advance to form the spherical joint;
block (312)) of the two pumps, and the pump P1 at same time, it reduces the thrust force
and pump P2 share one suction port. generated in axial direction through load
pressure; to ensure the low friction and flexible
Because the structure principles and working
movement between piston shoe and piston shoe
principles of the two pumps P1 and P2 are the
disc (211), adopt the annular oil groove of
same, the pump P1 will be described as
pressure balance (static pressure) on piston
example.
shoe. On the other hand, to enable the piston
The pump P1 is roughly composed of a rotating shoe subassembly (151, 152) can freely move
mechanism for driving the pump to rotate, a on the piston shoe disc (211) without any
swashplate mechanism for adjusting discharge separation, press the return disc (153) and
capacity and a valve cap mechanism for spherical bushing with the return spring (157)
alternately making oil suction and discharge onto the piston shoe disc. This end of the other
actions. cylinder block is also pressed onto the oil
distribution disc (313-314) by the return spring
(157).
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3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

The swashplate mechanism consists of ● Main pump regulator

swashplate (212), skid shoe disc (211),
Overview
swashplate support stand (251), inclined bushing
(214), inclined pin (531) and servo piston (532). The main oil pump adjuster is installed on the
The cylindrical section of the swashplate formed main oil pump and is composed of the following
at the opposite side of shoe sliding face is control mechanisms.
supported on the swashplate support platform
1. Power control
(251). The pressure oil controlled by the
regulator is led into the oil chambers at both ends As the piston pump’s own discharge pressure P1
of servo piston to enable leftward/rightward rises, the inclination angle (discharge flow) of the
movement of servo piston; it also enables the piston pump automatically reduces. As a result,
swash plate swinging on the support stand by the input torque is controlled below the fixed
help of the ball part of inclined pin so as to value. When the speed is constant, the input
change the inclination angle of swash plate (α). horsepower keeps constant.
The oil distribution cover mechanism consists of 2. Flow control
oil distribution cover (311, 312), supercharger The angle of inclination of piston pump can be
(130), spline coupler (114), oil distribution disc controlled conveniently by adjusting Max. flow
(313-314), oil distribution disc pin (885). The adjustment screw(discharge flow) . Tightening
spline coupler is connected between oil the adjusting handle for maximum flow reduces
distribution covers F and R, and driving shaft F the discharge flow Q. Otherwise, loosening the
and driving shaft R, and it also functions the adjusting handle for maximum flow increases the
boosting for suction pressure through the discharge flow Q.
centrifugal force of supercharge so as to
enhance the suction capacity of pump. The oil Using this mechanism, adjusting the adjusting
distribution disc with two incomplete arc shape lever for maximum flow as required by the
oil distribution windows is mounted on the oil operation can allow the piston pump to discharge
distribution body to fulfill the changeover actions the desired flow only, avoiding consuming power
of oil supply to and oil discharge from the in vain.
cylinder block. The oil switched by the oil 3. Pressure shut-off control
distribution disc connects with the external
pipeline through oil distribution body. When the This is a control mode to automatically reduce
driving shaft is driven by the prime mover (motor, the inclination angle (discharge flow) of the pump
engine and etc.), it rotates with the cylinder block when its own pressure reaches the set value.
by use of spline connection. When the swash Using this mechanism can get energy-saving
plate is inclined, the plunger mounted in the effects.
cylinder block rotates with the cylinder block
while it fulfills the reciprocating motion relative to The regulator has three or more control
the cylinder block. That is to say, considered for mechanisms. When various control mechanisms
1 plunger pair, in the range of rotation for 1 circle are used in a composite manner, the low-
of cylinder block, the plunger moves for 180° inclination-operation (low flow) command is
towards the direction away from the oil prioritized according to the calculation of the
distribution disc (oil suction travel), while for the mechanical equation described later.
residual 180°, it will move towards the oil
distribution disc (oil discharge travel). When the
inclination angle of swash plate (α) is zero, there
is no travel change of plunger (151, 152) so it
can discharge the oil.
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

Adjuster section diagram VIEW D

VIEW C SECTION B-B

412 Bolt 625 Spring 654 Return spring 756 O-ring

413 Bolt 626 Spring 655 Regulating Spring 763 O-ring
436 Bolt 627 Regulating lever 656 Cover 801 Nut
438 Bolt 628 Adjusting bolt 708 O-ring 802 Nut
496 Screw plug 629 Cover 722 O-ring 814 Snap ring
601 Valve body 630 Locknut 724 O-ring 836 Snap ring
611 Connecting rod 631 Guide bushing 725 O-ring 858 Snap ring
612 Connecting rod 641 Valve cover 728 O-ring 874 Pin
613 Connecting rod 643 valve rod 730 O-ring 875 Pin
614 Screw plug 644 Spring holder 732 O-ring 876 Pin
615 Adjusting plug screw 645 Regulating lever 733 O-ring 887 Pin
621 Piston 646 Spring 734 O-ring 897 Pin
622 Piston bushing 651 Valve bushing 735 O-ring 898 Pin
623 Intermediate extension rod 652 Spool 753 O-ring 924 Bolt
624 Spring holder 653 Spring holder 755 O-ring
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3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

Action principles When the slide valve (652) moves, the discharge
pressure P1 is directed to the large-diameter
1. Flow control
portion of the servo piston through Port C1. The
As shown in the right figure, the discharge flow of discharge pressure P1 is usually brought in the
the piston pump can be controlled at will based small-diameter portion of the servo piston, but
on the stroke S of the adjusting handle for the area difference allows the servo piston (532)
maximum flow to move right to reduce the angle of inclination.
When the servo piston (532) moves right, Point
D moves right too. The slide valve (652) is
equipped with a return spring (654) which
produces a pull to move the slide valve left.
Discharge flow Q

Therefore, the pin (897) is pressed towards the

large-hole portion [C] of the link (2)(613). Thus,
with the movement of the point D, the feedback
link (611) pivots on the point C, and the slide
valve (652) moves left. This movement allows
the sleeve (651) to close the opening of the slide
valve (652) gradually until the opening is closed
completely. Then, the servo piston stops.

Stroke of adjusting handle for maximum flow (2) Flow increase action
When the adjusting lever (675) is loosened, the
guide spring (646) pressure allows the guide
(1) Flow decrease action piston (643) to move left and the link (2) (613)
If the adjusting handle (675) for maximum flow is pivots on Point B. The pin (897) is pushed by the
tightened, the pilot piston (643) moves right via return spring (654) towards to the large-hole
the piston rod (642). The pin (875) fixed to the portion [C] of the link (2) through the slide valve
link (2) (613) is embedded in the grooved portion (652), the pin (874) and the feedback link (611).
[A] of the guide piston (643), so with the Therefore, with the rotation of the link (2) (613),
movement of the pilot piston (643), the link (2) the feedback link (611) pivots on Point D and the
pivots on Point B (fixed by the plug (614) and the slide valve (652) moves left.
pin (875). There is a projecting pins (897) fixed to When the slide valve (652) moves, Port C1 port
the feedback link (611) in the large-hole portion opens towards the tank port, so that the pressure
[C] of the link (2) (613), so with rotation of the link of the large-diameter chamber of the servo
(2) (613), the pin (897) moves right. The pin piston reduces. Due to the effect of the discharge
(548) fixed to the tilt pin (531) which allows the pressure P1 of the small-diameter portion, the
sloping plate to shake is embedded in the servo piston (532) moves left, so that the flow
double-sided width portion [D] of the feedback increases.
link (611). Therefore, when the pin (897) moves,
As the servo piston (532) moves, Point D also
the feedback link (611) pivots on Point D. The
moves left, the feedback link (611) pivots on
feedback link (611) connects with the slide valve
Point C, and the slide valve (652) moves right.
through the pin (874), so the slide valve (652)
The movement continues until the slide valve
moves right.
(652) closes the opening of the sleeve (651), and
stops there stationarily.
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

2. Power control The movement of the servo piston (532) is

conveyed to the feedback link (611) through
As shown in the right figure, when the load
Point D. The feedback link (611) pivots on Point
pressure increases, the inclination angle of the
F and the slide valve (652) moves left. The valve
piston pump can be reduced to prevent the prime
(652) keeps moving till the opening with the
mover from being overloaded.
sleeve (651) closes. Stop the action on the
position where the opening is just closed.
(2) Flow recovery action
If the piston pump’s own discharge pressure P1
Discharge flow Q

reduces, the compensation rod (623) will be

pushed back by the external spring (625) and the
internal spring (626). The link (1) (612) pivots on
Point E. As the link (1) (612) rotates, the
feedback link (611) pivots on Point D, and the
slide valve (652) moves left. Therefore, Port C1
port opens towards the tank port, so that the
pressure of the large-diameter portion of the
Discharge pressure (P1) servo piston reduces. The servo piston (532)
moves left, so that the discharge flow of the
piston pump increases.
The movement of horsepower control is the
The movement of the servo piston (532) is
same as the flow control. This is briefly described
transmitted to the slide valve (652) by the
below.
feedback mechanism. The piston continues to
(1) Overload prevention action move until the slide valve (652) closes the
When the piston pump’s own discharge pressure opening of the sleeve (651).
P1 rises, because P1 can be applied to the step 3. Priority mechanism of low inclination
of the compensation piston (621), the operation (low flow) command
compensation rod (623) is pushed right until the
As mentioned above, the inclination command of
elastic force of the external spring (625) and the
flow control and horsepower control is
internal spring (626) balances against the
transferred to feedback connecting rod (611) and
hydraulic pressure, and then the compensation
sliding valve (652) through the large hole part
rod stops moving. The movement of the
(Part C and F) connecting rod (1) (612),
compensation rod (623) is conveyed to the link
connecting rod (2) (613); since the parts C and F
(1) (612) through the pin (875). The link pivots on
adopts the structure of extruded pin (φ4) on the
the pin (875) [Point E] fixed to the pump housing
large hole (φ9), the pin (897) only contacts with
(601). There is a projecting pin (897) (fixed to the
the connecting rod with small inclination angle;
feedback link (611)) in the large hole [F portion]
the connection rod φ9 hole in large inclination
of the link (1) (612). As the link (1) (612) rotates,
command state will not contact with the pin (897)
the feedback link (611) pivots on Point D, and the
and present the free state. The low inclination
slide valve (652) moves right.
commands for flow control and horsepower
When the slide valve (652) moves, the discharge control are prioritized through this mechanical
pressure P1 is introduced into the large-diameter selection mode.
portion of the servo piston through the port C1.
Then, the servo piston (532) moves right, so that
the discharge flow of the piston pump is reduced
to prevent the prime mover from being
overloaded.
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3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

4. Pressure shut-off control 1. Adjustment of maximum flow

As shown in the right figure, when the pump’s (1) Adjustment of maximum flow (pump body
own discharge pressure P1 reaches the setting side)
pressure for shut-off, its inclination angle
(discharge flow) is reduced to the minimum.

Discharge flow Q
Discharge flow Q

Stroke of adjusting handle for maximum flow S

Discharge pressure (P1) Loosen the hex nut (808), and tighten (or loosen)
the fixing screw C (954) for adjustment. Keep
other control characteristics unchanged. Only
If the shut-off pressure is set at the value through change the maximum flow.
which the machine side is about to release,
energy-saving effects can be obtained. (2) Adjustment of maximum flow (with the
regulator’s adjusting lever for maximum flow)
When the pressure P1 directed to the safety
Loosen the lock knob (637), and tighten (or
valve (1) fixed to the cut-off valve reaches the
setting pressure for the safety valve (1), the loosen) the knob (675) for adjustment. Keep
other control characteristics unchanged. Only
safety valve (1) will start opening. The cut-off
change the maximum flow.
slide valve (647) moves left.
If the cut-off slide valve moves, the discharge During the 1) and 2) adjustment above, the low-
flow command is prioritized.
pressure P1 will be directed to the large-diameter
portion of the servo piston, then the servo piston 2. Adjustment of minimum flow (main pump)
moves right to minimize the pump’s inclination
Loosen the hex nut (808), and tighten (or loosen)
angle (discharge flow).
hex screw (953) for adjustment. Like the
Adjustment by adjuster adjustment of the maximum flow, keep other
This adjuster uses its adjusting screw to adjust control characteristics unchanged. But note that
if it is pulled too tight, the power needs to be
the maximum flow, minimum flow, horsepower
increased at the maximum discharge pressure
control characteristics and flow control
characteristics. (overflow).
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

(2) Adjustment of inter spring

Loosen the hex nut (801), and tighten (or loosen)
the adjusting screw QI(925) for adjustment. If the
adjusting screw C(628)needs to be tightened, as
shown in the right figure, the flow and input
Discharge flow Q

horsepower will increase.

Discharge flow Q
Stroke of adjusting handle for maximum flow S

3. Adjustment of input power

The regulator uses the constant horsepower
control method. To change the horsepower
Discharge pressure (P1)
setting, adjust the adjusting screws (628) and
(QI) (925).
(1) Adjustment of outer spring 4. Adjustment of pressure shutoff control
Loosen the hex nut (630), and tighten (or loosen) characteristics
the adjusting screw C (628) for adjustment. Loosen the hex nut (7), and tighten (or loosen) the
When the adjusting screw C (628) is tightened, spring holder (4) for adjustment. When the spring
as shown in the right figure, shift the control holder (4) is tightened, as shown in the right
diagram right, and increase the input figure, shift the control diagram right.
horsepower. Additionally, turn the adjusting
screw C (628) by N turns. As a result, the setting
of the internal spring (626) changes. Therefore,
turn the adjusting screw (QI) (925) in the
opposite direction by N × A turns. (A is the return
Discharge flow Q

rate)
Discharge flow Q

Discharge pressure (P1)

Failure causes due to the regulator and

troubleshooting

Discharge pressure (P1)

3-26
3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

When any poor movement happens, if it is

determined that it caused by the adjuster, refer to
the chapter "Removal and Installation" for
inspection under disassembled condition.
When prime motor is overload
1. Members of the compensation piston (621)
and compensation rod: disassembly,
cleaning
2. Slide valve (652) member: disassembly,
cleaning
When the maximum flow cannot be achieved,
1. Check whether the adjusting lever for
maximum flow is functioning properly
2. Rod piece of guide piston(643): disassembly,
cleaning
3. Slide valve (652) member: disassembly,
cleaning
(Note) If any part is scratched badly, replace it.
Electric proportional pressure-reducing valve
The electro-proportional pressure-reducing valve
(KDRRE5KR-V3-V) is used for changing the
control curve (P-Q curve) of the main oil pump
(P1/P2), providing the control curve for the main
oil pump under different operating conditions
(such as H, S, L mode). Its input pressure is Psv
(i.e. pilot pressure), and its output pressure is Pf
inversely proportional to input current.
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

Main Pump Maintenance References

When the abrasion loss of each part exceeds the following references, replacement or re-adjustment is
needed. But a part must be replaced when it has obvious damage in appearance.

Standard size Maintenance

Check items Treatments
(mm) limit (mm)
Space clearance (D-d) inside piston and
0.039 0.067 Change the piston or cylinder
cylinder
Looseness (δ) of clearance section between Change the piston and skid
0~0.1 0.3
piston and shoe shoe assembly parts.
Change the piston and skid
Thickness of shoe (t) 4.9 4.7
shoe assembly parts.
Free height (L) of cylinder spring 41.1 40.3 Change the cylinder spring.
Assembly height of plate and spherical bushing Change the plate or spherical
23.0 22.0
(H-h) bushing.

Looseness of clearance section between plunger

Space clearance inside piston and cylinder ball head and skid shoe: δ
block: D-d Thickness of skid shoe: t

Free height of cylinder block spring: L Assembly height of plate and spherical bushing:
H-h
3-28
3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

Maintenance standards of cylinder, valve block and swashplate (skid shoe plate).
Cylinder (sliding section) Finish to necessary roughness 3-Z (Ra=0.8)
Swashplate (skid shoe plate)
Roughness on each surface of Standard face roughness (corrected value) 0.4-Z (Ra=0.1) below (abrading)
cylinder (sliding section)

2. Pilot Pump

Pilot pump (P3 pump) is a quantitative type gear pump and provides the hydraulic system with pilot oil.
Pilot pump specifications

Model CLG930E CLG936E

Model ZX10LGRZ1-07A-V ZX15LHRZ1-07A-V
Weight kg 1.5 1.6
Displacement cm3/r 10 15

Set the pressure MPa +0.2

3.9 0
Rotation speed r/min 600~2500
Suction side pressure MPa 0.05 ~ -0.01
Rotation direction of shaft (from drive shaft) Clockwise

External view of pilot pump

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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

Section view of pilot pump

1. Front casing 7. Cone valve 12.Locknut 17.O-ring

2. Gear housing 8. Spring 13.VP oil plug 18.Bolt with washer
3. Drive gear 9. Ring 14.O-ring 19.Bolt with washer
4. Driven gear 10.Adjusting screw 15.Angular seal ring 20.Bolt with washer
5. Strainer 11.Locknut 16.O-ring 21.Lock ring
6. Valve seat

Principle of pilot pump

3-30
3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

The housing comprises a front housing (1) and a gear housing (2), with a pair of drive gear (3) and driven
gear (4) installed inside as well as a relief valve used for setting output pressure.
The relief valve comprises a strainer (5), a cone valve (7), a valve seat (6), a spring (8), a ring (9), an
adjusting screw (10) and a locknut (11).
To prevent oil from leaking outside, an angular seal (14) and an O-ring (13) are installed on the front
housing (1).
Working principle
Oil sucked in from the oil suction inlet B3 is discharged from oil discharge outlet A3 through the
drive•driven gear. Discharged oil is kept at setting pressure through the relief valve. Unwanted
discharged oil is discharged from the oil leakage port Dr of the main pump housing by means of the relief
valve.
Adjustment of the setting pressure of relief valve
Tightening the adjusting screw (10) by 90° increases the setting pressure by 5MPa.

3.3.2.2 Main Control Valve

Appearance drawing and structure diagram of main control valve see attached drawing for details, and
lists for specifications and parts are shown as follows:

Item Specifications
Model KMX15RB
Standard flow 300L/min
+1
Working pressure of main relief valve
34.3 0 MPa
+1
Pressurization pressure of main relief valve
37.3 0 MPa

Setting pressure of oil port relief Boom, arm and bucket 39.2±0.5MPa
valve Spare 30.0±0.5MPa
Working oil temperature -20~90°C
Maximum pressure of leaking oil 0.3MPa

List for main control valve parts:

Serial number Serial number

Part name Part name
in the figure in the figure
101 Valve body A 309 Backup spool
102 Valve body B 310 Bypass stop spool
151 Plunger 311 Rotary priority valve spool
152 Plunger 314 Right travel spool
153 Plunger 320 Spring
154 Plunger 321 Spring
156 Orifice plug 322 Spring
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

Serial number Serial number

Part name Part name
in the figure in the figure
158 Plug 323 Spring
159 Plug 326 Spring
161 O-ring 327 Spring
162 O-ring 328 Spring
163 O-ring 329 Spring
164 O-ring 330 Spring
165 O-ring 331 Spring holder
166 O-ring 332 Spring holder
168 O-ring 333 Bolt with a liner
201 Spring cover 335 Stopper
202 Spring cover 336 Bolt with a liner
203 Spring cover 337 Stopper
204 Spool cover 339 Stopper
205 Spool cover 372 Spring
206 Spool cover 373 Spring
209 Flange 511 Cone valve
210 Plate 512 Cone valve
211 Plunger 513 Cone valve
251 Logic control valve 514 Cone valve
252 The lock valve selector pair 521 Spring
254 Rotary logic valve group 522 Spring
256 Arm 2 logic valve group 523 Spring
257 Arm regeneration stop valve pair 541 Steel ball
258 Plunger 542 Spring holder
259 Plunger 543 Spring
261 O-ring 550 Plunger
262 O-ring 551 Plunger
264 O-ring 552 Plunger
273 Hexagon socket bolt 553 Plunger
274 Hexagon socket bolt 561 O-ring
301 Left travel spool 562 O-ring
302 Arm 1 spool pair 601 Main relief valve
303 Boom 1 spool pair 602 Port relief valve
304 Bucket spool 604 Port relief valve
305 Swing spool 610 Negative control relief valve
306 Spool of arm 2 971 Hexagon socket bolt
307 Spool of boom 2 975 Hexagon socket bolt
308 Straight travel spool pair 977 Nameplate
978 Rivet
3-32
3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

The ports of the main control valve are shown in following table

Port
Symbols Port name
dimension
G-1 R2 Oil filler joint

(P0)
G-3/4 (P3)
(P5)

XAtr Right travel (reversing) apilot interface

XBtr Right travel (advancing) pilot interface
(XAo) (Backup pilot interface)
(XBo) (Backup pilot interface)
XAk Bucket (excavate) pilot interface
XBk Bucket (unloading) pilot interface
XAb1 Boom 1 (rise) pilot interface
XBb1 Boom 1 (lowering) pilot interface
G-3/8 XAa2 Arm 2 (stretch) pilot interface
XBa2 Arm 2 (retraction) pilot interface
XAtL Left travel (reversing) pilot interface
XBtL Left travel (advancing) pilot interface
XAs Swing (left swing) pilot interface
XBs Swing (right swing) pilot interface
XAa1 Arm 1 (stretch) pilot interface
XBa1 Arm 1 (retraction) pilot interface
Dr1 Oil leakage port
Px Signal interface for work implement
Py Signal interface for travel
Pz Pilot pressure for pressurization of main relief valve
PG Pilot pressure source interface
N1 Negative control signal pressure interface (boom 1 side)
N2 Negative control signal pressure interface (arm 1 side)
Pns Rotary logic control valve pilot interface
PCk Bucket (excavation) stroke limiting pilot interface
PnA2 Arm 2 logic control valve pilot interface
G-1/4 Dr2 Oil leakage port
Dr3 Oil leakage port
Dr6 Oil leakage port
Dr7 Oil leakage port
PaL Lock valve pilot interface (arm piston rod side)
PbL Lock valve pilot interface (boom piston head side)
(XBp1) Bypass stop spool pilot interface (P1 side)
XBp2 Bypass stop spool pilot interface (P2 side)
XAb2 Boom flow merging (lifting) pilot interface pressure
Psp Rotation priority pilot port

M12 R1 Oil return port

 3-33
December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

Port
Symbols Port name
dimension
Atr Right travel motor interface (reversing)
Btr Right travel motor interface (forward)
(Ao) Backup port
(Bo) Backup port
Ak Interface (excavation) at bucket cylinder piston head side
Bk Interface (unloading) at bucket cylinder piston rod side
Ab Interface (lifting) at boom cylinder piston head side
Bb Interface (lowering) at boom cylinder piston rod side
M10
AtL Left travel motor interface (backward)
BtL Left travel motor interface (forward)
As Swing motor interface (left rotation)
Bs Swing motor interface (right rotation)
Aa Interface (extension) at arm cylinder piston rod side
Ba Interface (retraction) at arm cylinder piston head side
P1 Pump port (P1 side)
P2 Pump port (P2 side)

a. The ports in () are valve blocks in general.

3-34
3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

Main control valve hydraulic circuit

Straight travel
Travel (right)

Travel (left)
Slewing

Slewing priority

Boom 1
Boom 2

Bucket
Spare

Arm 1 Arm 2

Bypass stop

Hydraulic circuit diagram

 3-35
December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

Working Principle

1. When the spool is in the neutral position

[Main circuit]
When all spools are in neutral state, the working oil fed from the hydraulic pump (front) flows into the
pump interface P1, is guided to the main passage (1) and returns to the working oil tank from the return
interface (R1) by the neutral bypass (2) (natural M neutral M-shaped slide valve function) of each spool
of linear travel (308), left travel (301), boom 1(303), bucket (304) and arm (306).
The signals of the negative control relief valve (610) at the boom 1 side are transmitted into the hydraulic
pump adjuster at the P1 side from the interface N1 to control the pump output flow as the minimum flow.
The working oil fed from the hydraulic pump (back) flows into the pump interface P2, is guided to the
main passage (3), and returns to the working oil tank from the return interface (R1) by the neutral bypass
(2) (neutral M-shaped slide valve function) of each spool of flowing into the right travel (301), rotation
(305), boom flow merging (boom 2: 307), backup (309) and arm 1 (302).
In addition, the signals of the negative control relief valve (610) at the arm 1 side are transmitted into the
hydraulic pump adjuster at the P2 side from the interface N2 to control the pump output flow as the
minimum flow.
Whichever out of the 9 main spools is switched, the neutral bypass (2) will be immediately closed. The
signal pressure at the interface N1 or N2 in the negative control circuit is the tank pressure, and controls
the pump output flow as the maximum flow.
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3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E
 3-37
December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

2. Traveling

[Pilot circuit]
When the left or right travel spool is switched, the side passage is closed, and thus the pressure at the
interface Py (signal interface for travel) rises.
[Main circuit]
When the pilot interface XBtL for the left travel spool (301) is pressurized,
The neutral bypass (2) at the boom 1 side is closed, and the working oil fed from the hydraulic pump
(front) is fed into the left travel motor from the interface BtL.
Similarly, when the pilot interface XBtr for the right travel spool (301) is pressurized, the neutral bypass
(2) at the arm 1 side is closed, and the working oil fed from the hydraulic pump (back) is fed into the right
travel motor from the interface Btr.
On the other hand, the return oil respectively from the left and right travel motors passes through the left
(right) travel spool from the interface AtL (Atr), and then returns to the working oil tank from the return oil
interface (R1).
When the travel on the opposite side (pressurizing the pilot interfaces XAtr and XAtL) is operated, the
process is the same as the above.

Swing motor
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3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

3. Arm

1. During the arm extending operation

[Pilot circuit]
When the arm 2 spool (306) is switched, the side passage is closed, and thus the pressure at the
interface Px (signal interface for work implements) rises.
[Main circuit]
During the arm extending operation, pilot pressure oil is fed into the interfaces XAa1 and XAa2. When
pilot pressure oil is applied to both sides of the ports XAa1, XAa2, the arm 1, arm 2 spools are
respectively switched to the left of the Figure, and thus the working oil flowing into P2 is guided to the
neutral bypass (2) through the main passage (3). By switching the arm 1 spool (302), the neutral bypass
is cut off, and thus the working oil flowing into the parallel passage pushes open the cone valve (511) of
the check valve, flows into the arm 1 spool (302) from the U-shaped passage, then flows into the
periphery of the arm 1 spool (302) and arm 2 spool (306), and is fed into the arm cylinder piston rod side
from the interface Aa.
On the other hand, the working oil flowing into the interface P1 is fed into the neutral bypass (2) through
the main passage (1). By switching the arm 2 spool (306), the neutral bypass is cut off. Thus the working
oil flowing into the parallel passage pushes open the logic cone valve (256-101) of the arm 2 logic valve
gp, while the working oil flowing into the neutral bypass pushes open the cone valve (511) of the check
valve. They both flow into the arm 2 spool (306) from the U-shaped passage, then merge with the
interface Aa from the internal passage of the arm 2 spool (306), and are fed into the arm cylinder piston
rod side (R).
The return oil from the arm cylinder piston head side (H) through the interface Ba flows to the respective
tank oil circuit of the arm 1 and arm 2, and returns to the working oil tank from the tank interface (R1).
 3-39
December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

During the arm extending operation

3-40
3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

2. During the arm retracting operation

[Pilot circuit]
When the arm 2 spool (306) is switched, the side passage is closed, and thus the pressure at the
interface Px (signal interface for work implements) rises. Meanwhile, pressure oil is fed into the interface
PaL, and the release signal of the lock valve selector pair (252) is sent over.
[Main circuit]
During the arm retracting operation, pilot pressure oil is fed into the interfaces XBa1 and XBa2. When
pilot pressure oil is applied to both sides of the interfaces XBa1, XBa2, the arm 1, arm 2 spools are
respectively switched to the right of Figure one. Thus the working oil flowing into P2 is guided to the
neutral bypass (2) through the main passage (3). By switching the arm 1 spool (302), the neutral bypass
is cut off. Thus the working oil flowing into the parallel passage pushes open the cone valve (511) of the
check valve, flows into the arm 1 spool (302) from the U-shaped passage, then flows into the periphery
of the arm 1 spool (302), and is fed into the bucket cylinder piston head side (H) from the interface Ba.
On the one hand, the working oil flowing into the interface P1 is guided to the neutral bypass (2) through
the main passage (1). By switching the arm 2 spool (306), the neutral bypass is cut off, and thus the
working oil flowing into the parallel passage pushes open the logic cone valve (256-101) of the arm 2
logic valve gp, while the working oil flowing into the neutral bypass pushes open the cone valve (511) of
the check valve. They both flow into the arm 2 spool (306) from the U-shaped passage, then merge with
the interface Ba from the internal passage of the arm 2 spool (306), and are fed into the arm cylinder
piston head side (H).
On the other hand, the return oil from the arm cylinder piston rod side (R) makes the working oil with
increasing pressure return to the interface Aa through the self weight of the arms etc. The working oil
having returned to the interface Aa flows into the spool from a hole on the periphery of the arm 1 spool
(302); only under low load, it will push open the cone valve (302-317) inside the spool and merge with
the interface Ba from a hole on the spool. This is called the arm regeneration function.
If the pressure at the arm cylinder piston head side and in the U-shaped passage rises, the arm
regeneration stop spool (257-211) is switched to the left of Figure two, and is closed through the back
pressure of the cone valve (302-317) inside the spool simultaneously. Thus the arm regeneration
function is released. The return oil from the arm cylinder piston rod side (R) flows into the spool from the
hole (a) on the periphery of the arm 1 spool (302), then flows to the arm regeneration stop valve pair
(257) from the hole (c) on the periphery of the arm 1 spool (302), and returns to the working oil tank
through the tank interface (R1).
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

During the arm retracting operation Figure one

Small load

Arm dead-weight

LG922E930E03056
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3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

During the arm retracting operation Figure two

When the pressure on the side of arm cylinder piston head (H) rises
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

4. Boom

1. When the boom is operated to lift

[Pilot circuit]
When the boom 1 spool (303) is switched, the side passage is closed, and thus the pressure at the
interface Px (signal interface for work implements) rises.
[Main circuit]
During the boom lifting operation, pilot pressure oil is fed into the interface XAb1, and the boom 1 spool
(303) moves to the left of Figure. The working oil flowing into the port P1 is guided to the neutral bypass
(2) via the main passage (1). By switching the boom 1 spool (303), the neutral bypass is cut off, and thus
the working oil flowing into the parallel passage pushes open the cone valve (511) of the check valve,
flows into the boom 1 spool (303) from the U-shaped passage, then flows into the periphery of the boom
1 spool (303), and is fed into the boom cylinder piston head side (H) from the interface Ab.
Meanwhile, pilot pressure oil is also fed into the interface XAb2, and the boom 2 spool (307) moves to
the right of Figure. As the neutral bypass is cut off by switching the boom 2 spool (307), thus the working
oil from P2 flowing into the parallel passage flows into the boom 2 spool (307) by means of the U-shaped
passage, then pushes open the cone valve (511) of the check valve, and is fed into the boom cylinder
piston head side (H) after merging with the interface Ab. This is called the boom flow merging function.
On the other hand, the return oil from the boom cylinder piston rod side (R) flows into the periphery of the
boom 1 spool (303) from the interface Bb, and returns to the working oil tank from the tank interface
(R1).
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3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E
 3-45
December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

2. During boom lowering operation

[Pilot circuit]
When the boom 1 spool (303) is switched, the side passage is closed, and thus the pressure at the
interface Px (signal interface for work implements) rises. Meanwhile, pressure oil is fed into the interface
PbL, and the release signal of the lock valve selector pair (252) is sent over.
[Main circuit]
During the boom lowering operation, pilot pressure oil is fed into the interface XBb1, and the boom 1
spool (303)moves to the right of Figure. The working oil flowing into the interface P1 is guided to the
neutral bypass (2) by means of the main passage (1). By switching the boom 1 spool (303), the neutral
bypass is cut off. Thus the working oil flowing into the parallel passage pushes open the cone valve (511)
of the check valve, flows into the boom 1 spool (303) from the U-shaped passage, then flows into the
periphery of the boom 1 spool (303), and is fed into the boom cylinder piston rod side (R) from the
interface Bb.
On the other hand, the return oil from the boom cylinder piston head side (H) passes through the hole (a)
and periphery of the boom 1 spool (303).
3-46
3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

The return oil makes pressure rise through the self weight of the booms. To maintain sufficient pressure,
the cone valve (303-317) inside the spool is pushed towards the right of Figure by means of the internal
spool passage, and the return oil flows out of the spool. This pressure oil acts as the working oil for the
boom lowering operation and is again fed into the boom cylinder piston rod side (R), which is called the
boom regeneration function. Part of the return oil flowing into the internal spool passage from the hole (a)
returns to the working oil tank by means of the hole (b).
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

5. Bucket

1. During bucket excavation operation

[Pilot circuit]
When the bucket spool (304) is switched, the side passage is closed, and thus the pressure at the
interface Px (signal interface for work implements) rises. Meanwhile, pressure oil is also fed into the
interface XBp2.
[Main circuit]
During the bucket excavation operation, pilot pressure oil is supplied into the interface XAk, and the
bucket spool (304) moves to the right of Figure. The working oil flowing into the port P1 is guided to the
neutral bypass (2) via the main passage (1). By switching the bucket spool (304), the neutral bypass is
cut off. Thus the working oil flowing into the parallel passage pushes open the cone valve (511) of the
check valve, flows into the bucket spool (304) from the U-shaped passage, then flows into the periphery
of the bucket spool (304), and is fed into the bucket cylinder piston head side (H) from the interface Ak.
On the other hand, the return oil from the bucket cylinder piston rod side (R) flows into the interface Bk,
and then flows to the tank interface (R1) from the periphery of the spool to return to the working oil tank.
During the simultaneous boom lifting and bucket excavation operation, pilot pressure oil is fed into the
interface Pck, and thus the stroke of the bucket spool is not only be limited within the full stroke but in a
halfway position. Thus the passage of the bucket cylinder is throttled, and working oil also flows into the
boom 1 spool (303) from the bucket spool (304). Therefore, the boom lifting operation takes priority.
3-48
3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

2. During bucket unloading operation

[Pilot circuit]
When the bucket spool (304) is switched, the side passage is closed, and thus the pressure at the
interface Px (signal interface for work implements) rises. Meanwhile, pilot pressure oil is also fed into the
interface XBp2.
[Main circuit]
During the boom lifting operation, pilot pressure oil is fed into the interface XAb1, and the bucket spool
(304) moves to the left of Figure. The working oil flowing into the port P1 is guided to the neutral bypass
(2) via the main passage (1). By switching the bucket spool (304), the neutral bypass is cut off. Thus the
working oil flowing into the parallel passage pushes open the cone valve (511) of the check valve, flows
into the bucket spool (304) from the U-shaped passage, then flows into the periphery of the bucket spool
(304), and is fed into the bucket cylinder piston rod side (R) from the interface Bk.
On the other hand, the return oil from the bucket cylinder piston head side (H) flows into the interface Ak,
and then flows to the tank interface (R1) from the periphery of the spool to return to the working oil tank.

3. Bucket flow merging

During the bucket excavation operation, pilot pressure oil is also supplied into the interface XBp2, and
the neutral bypass stop spool (310) is switched. Working oil supplied via the interface P2 is guided into
the neutral bypass (2) via the main passage (3). The neutral bypass is cut off by switching the neutral
bypass spool (310). So working oil pushes open the check valve (514) and merges with flow in the
bucket spool (304) via the internal passage and the U-shaped passage.
 3-49
December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

6. Swing

1. During individual rotation

[Pilot circuit]
When the swing spool (305) is switched, the side passage is closed, and thus the pressure at the
interface Px (signal interface for work implements) rises.
[Main circuit]
During individual rotation, pilot pressure oil is supplied into the interface XAs (or interface XBs) to switch
the rotary spool (305). The working oil flowing into the port P2 is guided to the neutral bypass (2) via the
main passage (3). The neutral bypass is cut off by switching the swing spool (305). So working oil
flowing in the parallel passage pushes open the logic cone valve (254-101) of the rotary logic valve
group, flows in the rotary spool (305) via the U-shaped passage, then flows into the periphery of the
rotary spool (305) and is supplied to the swing motor via the interface As (or interface Bs).
On the other hand, return oil from the swing motor flows in from the interface Bs (or interface As), flows
into the oil tank interface (R1) via the periphery of the spool and then returns to the working oil tank.

Swing motor
3-50
3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

2. Rotation priority function

[Pilot circuit]
Pilot pressure oil is supplied into the interface Psp to switch the rotary priority spool (311).
[Main circuit]
Because the opening area of the rotary priority spool decreases by switching the rotary priority spool
(311), working oil from the spool (302) of the arm 1 also flows back the rotary spool (305) so that rotation
takes priority.
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

7. Spare

The backup spool is used for controlling various additional devices.

1. Optional operation
[Pilot circuit]
When the standby spool (309) is switched, the bypass is closed, so the pressure of the interface Px
(signal interface for working device) rises.
[Main circuit]
When the standby spool is operated, pilot pressure oil is supplied into the interface Px (or interface XBo)
to switch the standby spool (309). The working oil flowing into the port P2 is guided to the neutral bypass
(2) via the main passage (3). The neutral bypass is cut off by switching the standby spool (309). Thus the
working oil flowing in the parallel passage pushes open the cone valve (511) of the check valve, flows in
the standby spool (309) via the U-shaped passage, then flows into the periphery of the standby spool
(309) and is supplied to the additional devices via the interface As (or interface Bo).
On the other hand, return oil from the additional devices flows in from the interface Bo (or interface Ao),
flows into the oil tank interface (R1) via the periphery of the spool and then returns to the working oil
tank.
3-52
3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

2. Backup flow merging

To merge standby flow, pilot pressure oil is also supplied to the interface XBp1 to switch the bypass stop
spool (310). The working oil flowing into the port P1 is guided to the neutral bypass (2) via the main
passage (1). The neutral bypass is cut off by switching the bypass stop spool (310), so that working oil
pushes open the cone valve (514) of the check valve and merges with the flow in the standby spool
(309) via the internal passage and the U-shaped passage.

8. Straight Travel

When the travel spool (301) is operated together with other spools.
The condition where the travel spool (301) and the rotary spool (305) are simultaneously operated is
described below. (When pilot pressure oil is supplied to the interfaces XAtL, XAtr and XAs)
[Pilot circuit]
The side passage of right travel and left travel spools (301) and the side passage of the rotary spool at
the downstream side are closed, pilot pressure oil from the interface PG is supplied to the interface PTa,
and the linear travel spool (308) is switched.
[Main circuit]
When the linear travel spool (308) is switched, the right travel and left travel spool (301) is preferentially
communicated with the interface P2, the parallel passage of the rotary , boom 2 standby , arm 1 oil
passage/boom 1 bucket and arm 2 oil passage is preferentially communicated with the interface P1, so
that working oil supplied from the interface P2 mainly flows into the interface AtL and the interface Atr
and is evenly supplied to two travel motors.
On the other hand, working oil supplied from the interface P1 is also supplied to the swing motor via the
interface As.
 3-53
December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

When the pressure oil in the interface P2 is lower than that of the interface P1, one part of working oil
supplied from the interface P1 is supplied to the P2 side. So the rapid decrease of travel speed can be
prevented.

9. Function of lock valve

The lock valve selector pair (252) is installed among the arm cylinder piston rod side (R), the arm 1 spool
(302) and the arm 2 spool (306) to reduce the internal leakage of the spool caused by cylinder pressure.
Likewise, a lock valve selector pair (252) is also installed between the boom cylinder piston head side
(H) and the boom 1 spool (303) to reduce the internal leakage of the spool caused by cylinder pressure.
1. (1) Spool neutral state
The condition where the boom 1 spool (303) is selected is shown below. (The condition of arm 2 spool
(306) is also the same.)
When the boom 1 spool (303) is neutral, the spool (252-511) inside the lock valve selector pair is kept in
the position as shown in Figure by the pretightening force of the spring (252-321) and is pressed in the
valve seat of the valve bushing (252-541) inside the lock valve selector pair.
3-54
3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

In this position, working oil at the boom cylinder piston head side (H) flows in from hole (a), flows across
the periphery of the spool (252-511) of the lock valve selector pair and presses the valve seat of valve
body of the cone valve (513) at hole (b) so as to reduce internal leakage.
 3-55
December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

2. During boom lowering operation

When the boom is operated to lower, pilot pressure oil is supplied into the interface PbL and the interface
XBb1. The spool (252-511) inside the lock valve selector pair moves to the upper side of Figure through
pilot pressure oil. The hole (a) is first cut off through the movement of the spool (252-511) inside the lock
valve selector pair, and working oil from the boom cylinder piston head side (H) does not flow into the
spring chamber (RH). In addition, oil in the cavity of spring chamber (RH) flows into the leakage oil circuit
via the hole (b). Therefore, the cone valve (513) is jacked through the pressure at the boom cylinder
piston head side (H), and the function of the lock valve selector pair (252) is released.

3. When the boom is operated to lift

During the boom lifting operation, pilot pressure oil is fed into the interface XAb1. The cone valve (513) is
pushed open through oil flowing in via the boom 1 spool (303), so working oil flows into the interface Ab.
3-56
3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

10. Function of Main Relief Valve

The main relief valve is installed on the valve body A (101) and has the following functions:
1. Working oil fills the cavity of chamber (a) by means of the holes in the valve seat (541) and small
holes in the valve plunger (512) through the passage (P), and the valve plunger (512) is pressed
against the valve seat (541) to form reliable seal.
2. When the pressure inside the passage (P) exceeds the pretightening force of the spring (621), the
cone valve (611) is opened, so working oil flows into the low pressure passage (R) from the periphery
of the cone valve (611) and across the holes in the valve bushing (103).
3. The pressure inside the cavity (a) drops due to the opening of the cone valve (611), and the valve
plunger (512) is opened. Therefore, working oil in the passage (P) directly flows into the low pressure
passage (R).
When pressure oil above 3MPa is supplied into the interface Pz, the pressure oil pushes the plunger
(614) to move leftwards to change the setting load of the spring (621), and the pressure starts to rise.
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

11. Function of Port Relief Valve

The interface relief valve is installed between the cylinder interface and the low pressure passage.
Besides the function as a relief valve, the interface relief valve also has the function as a check valve for
preventing cavitation and replenishing oil.
1. Function as a relief valve
a. Working oil fills the cavity of chamber (B) via hole (A) of the plunger (301) and presses the valve
plunger (511) against the valve seat (541), and the valve seat (541) is pressed against the valve
seat of the valve body to form reliable seal.
3-58
3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

b. When the pressure inside the passage (P) exceeds the elastic force of the spring (621), the cone
valve is opened, so working oil flows into the low pressure passage (R) from the periphery of the
cone valve (611) and across the hole (C).
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element
3-60
3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

c. The pressure inside the cavity of chamber (B) drops due to the opening of the cone valve (611),
and the valve plunger (512) is opened. Therefore, working oil in the passage (P) directly flows into
the low pressure passage (R).
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element
3-62
3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

2. Function as a check valve for preventing cavitation and replenishing oil

When the passage (P) generates negative pressure, working oil is supplied from the passage (R). When
the pressure of the passage (R) is higher than the pressure of the passage (P), the valve seat (541)
moves rightwards. Therefore, working oil is guided into the passage (P) from the passage (R) through
the periphery of the valve seat (541) so as to prevent cavitation.
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

12. Function of Negative Control Relief Valve When the pressure of the interface P is greater
than the setting pressure of the spring (321) as
The negative control relief valve is installed shown in Figure, the cone valve (511) is opened,
between the most downstream of the neutral by- and working oil in the interface P flows to the low
pass and the low pressure passage. The function pressure passage (R) through the periphery of
of the negative control relief valve is shown the cone valve (511).
below.
(1) If the pressure of the interface P is smaller
than the setting pressure of the spring (321), the
cone valve (511) is in the state shown in Figure
below. The pressure bearing section φB of the
cone valve (511) is cancelled by the section φA
of damping rod (512), and the pressure bearing
area is φB-φA at the moment. Working oil in the
interface P flows to (R) through the orifice (c).

Through the above change, the relationship

between the flow Q of working oil flowing from
the interface P to the low pressure passage (R)
and the pressure change is shown in the
following figure.

Pressure

Flow
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3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

Maintenance References

Part name Inspection item Judgment references Treatments

1) Valve holes in the valve body and spool slide
section, especially spool shoulder related to
pressure maintenance is damaged
2) The O-ring contact face between the spool cover
Presence of scratches, and the spring cover is damaged.
Valve body bruises, rust and 3) The interface seal in contact with O-ring is Replacement
corrosion damaged.
4) The seal of each relief valve of main interfaces is
damaged.
5) The seals of plunger and plug are damaged.
6) Other damages affecting normal function
Presence of scratches, Replace (especially
When there are bruises caused by jamming of sliding
bruises, rust and the section in contact
on the periphery
corrosion with the seal)
O-rings and seals at both
Sliding section is damaged Replacement
ends
Spool
Insert the spool into the
valve hole, and observe
Repair or
the condition where the O-ring is damaged or the spool acts unsmoothly
replacement
spool rotates while moves
to make travel.
Each spring is damaged The spring is damaged Replacement
Each cone valve is The cone valve is damaged and cannot be fully Repair or
damaged sealed replacement
Cone valve Install the spool of each
check valve into the valve
Normal, no need of
hole of the valve body, It isn’t jammed and can act easily and freely
treatment
and observe its action
condition
Check the spring, spring
Around holder, plunger and cover
Part has significant damages Replacement
spring are not rusted, deformed
or fractured.
Repair or
Around the Oil leakage outward Oil leakage
replacement
sealing
section of the Whether the seal plate is
Repair or
spool rusted, corroded and The seal plate is rusted, corroded and deformed.
replacement
deformed.
Whether there is rust and
There is rust and fracture on appearance Replacement
fracture on appearance.
1) Main
Contact face of the valve
Relief Valves The contact face of the valve seat is damaged. Replacement
seat
2) Interface
relief valve The contact face of each
The contact face of the spool is damaged Replacement
3) Negative spool
control relief Abnormal spring Abnormal spring Replacement
valve
O-rings, snap rings and
Replace all of them in principle Replacement
seals
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

3.3.2.3 Center Joint

center joint is mainly used for connection of hydraulic access with close range, and for connecting
relatively fixing parts and rotating parts, which is characterized by high pressure resistance, wear
resistance, multiple accesses, mutual noninterference for rotating 360°, simple connection, safety,
reliability, etc.
The structure of the center joint is shown in the figure below:

22.Retainer 25.Retainer 28.Spindle 30.O-ring

23.Cover 26.Seal ring 29.Bushing 31.Dust ring
24.O-ring 27.Center joint body

X2: travel motor-rh high-speed/low- B1: travel motor-lh B port B2: travel motor-rh B port
speed switching port P A2: travel motor-rh A port L: left and right travel motor oil drain
A1: travel motor-lh port A port
3-66
3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

Working Principle

The center joint is composed of the swing body, swing shaft, end cover and other parts, and swing body
(or swing shaft) is fixed on upper part (or lower part) of the vehicle body, but swing shaft (or swing body)
is installed on lower part (or upper part) of vehicle body and can rotate 360° freely. Slot annular grooves
on swing shaft with the same number of oil line, and hydraulic oil entering into oil inlet of swing body
connects with radial hole on swing shaft through oil groove on swing body, and supplies travel motor.
Because the annular grooves on swing body and swing shaft are closed, no matter whether swing body
or swing shaft rotates along with vehicle body, the mutually corresponding oil port is always independent
and smooth, which guarantees normal flowing of hydraulic oil. See details in following figure

Working Schematic Diagram

of Central Swivel Joint

Body port

Shaft port

Fault Analysis

No. Fault symptom Fault cause Countermeasures

1. Dust impurities enter the neck to 1. Take dust-prevention measures for base
damage neck seal; machine
Oil leakage of neck 2. The connection is subject to 2. The products must meet installation
1
part external force during installation, requirements when being connected and
causing single side abrasion of the installed;
seal to lead to oil leakage. 3. Replace sealing part.
Loosening of fastening bolt or
Oil leakage at the
2 damage and aging of seal at the place Retighten the bolt, and replace the seal.
place of end cover
of end cover.
Oil leakage of oil Hydraulic pipeline fitting connecting
3 Replace with new hydraulic pipeline fitting.
port with oil port is damaged
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

3.3.2.4 Explosion Relief Valve

The hose explosion relief valve is optional and its schematic diagram is as follows:

32.Adjustable throttle valve 34.Relief valve 36.Check valve

33.Throttle valve 35.Spool 37.Strainer

If the explosion-proof valve is selected, it is The relief valve (3) is used for protecting
directly installed on the cylinder (boom cylinder cylinders from being damaged under the action
big cavity and arm cylinder small cavity) to of external force. When external force impacts
prevent the control cylinder from suddenly the cylinder, impact pressure passes through the
dropping without the action of gravity after hose (6) strainer and outputs pressure signals to the
bursting to cause accidents. balanced valve (4) through the relief valve (3) to
open the balanced valve. The pressure of the
During normal working, oil enters the cylinder
cylinder is released. The check valve at the lower
through the check valve (5). During reverse
right corner ensures enough pressure to open
action, oil needs to cooperate with the pilot signal
the balanced valve (4) can be created after the
to enter the control port of the balanced valve (4)
impact pressure passes through the relief valve
through the check valve (5) at the lower right
(3).
corner so as to open the balanced valve. Oil
flows out of explosion relief valve through The setting pressure of the relief valve (3) is the
balanced valve (4). maximum pressure that the cylinder cannot be
damaged. When the impact pressure does not
After the hose bursts suddenly, hydraulic oil in
reach the relief pressure of the relief valve (3),
the hydraulic cylinder cannot pass through the
the relief valve (3) cannot overflow, and the
valve due to the blocking of the spool of the
explosion relief valve cannot be opened in the
balanced valve (4). When the system uses two
reverse direction.
identical cylinders, one small balance line is used
to balance the pressure between the cylinders.
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3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

After the hose bursts, the cylinder can be slowly 3.3.2.5 Hand Pilot Valve
lowered by adjusting the relief valve (3).
However, after the cylinder is lowered to the First side
Maximum pressure is 6.9 MPa
safety position, the safety pressure of the relief pressure
valve (3) needs to be reset. The safety pressure Secondary 0~4.4 (maximum control pressure)
of the relief valve (3) for protecting the cylinder side pressure MPa
from being damaged has been set while leaving Allowable
the factory. After adjustment, the relief valve Maximum 0.3 MPa
backpressure
needs to be reloaded to the test bench to set the
Rated flow
safety opening pressure. rate
20L/min

Operating
±19°
angle
Mass 1.9kg
The safety pressure of the relief valve (3) is
In order to obtain well responsiveness,
used for protecting the cylinder from being appropriate pipeline is the one with
damaged. Do not adjust without permission. inner diameter as φ8 and length as
After adjustment for specific reasons, please Pipeline
about 3m. In addition, return oil shall
restore to the factory setting pressure. not be affected by other backpressures
and directly enter into tank.

1. Control lever
2. Pilot valve
The hand pilot control valve is composed of a
control lever (1) and a pilot valve (2). It can
control two working devices, left pilot controls
rotation and arm, and right pilot controls bucket
and boom.
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

Working principle 1. Pressure plate 7. Restoring 12.Oil port

2. Push rod spring 13.Oil inlet cavity
Schematic diagram of hand pilot valve 3. Spring 8. Return cavity 14.Oil return
4. Dowel bar 9. Oil return passage
5. Spring holder passage 15.Oil inlet
6. Pressure 10.Oil inlet passage
spring passage 17. Oil port
11.Valve stem

When the control lever pulled rightwards, the

presser plate (1) tilts rightwards. The pressure
plate (1) pushes the push rod (2) downwards, it
brings the Spring holder (5) to overcome the pre-
tightening forces of the pressure adjusting spring
(6) and restoring spring (7) to move downwards.
The valve stem (11) also moves downwards
under the action of force of the spring (6). The oil
inlet passage (10) is opened. Pilot oil flows from
the oil inlet cavity (13) to the port of the main
1,2,3,4: oil inlet and outlet ports valve control valve rod through the passage (10)
P: pilot pressure oil port and via the oil port (12). Pilot pressure oil makes
T: pilot oil return port the main control spool move, and corresponding
Structural schematic diagram of hand pilot valve actuating mechanism under control acts to
operate or rotate.
Pilot oil at the another port of the main valve
control valve rod returns to the oil port (17), and
the return passage (14) is opened and the oil
inlet passage (15) is closed because the push
rod is not pressed by the presser plate. Pilot oil
returned to the oil port (17) enters the return
cavity through the return passage (14) and
returns to the system oil tank via the hand pilot
valve.
Therefore, the control lever generates one angle,
the pressure adjusting spring (6) is compressed
and pretightened, the pressure adjusting spring
(6) will also make the valve stem (11) move
downwards, the oil inlet passage (10) is opened,
pilot pressure oil reaches one end of the main
valve control valve stem through the oil inlet
passage (10), and thus, the angle of the main
control valve stem corresponding to the control
lever generates a certain displacement.
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3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

When the pilot lever slightly swings to a small

angle under non-operative state, the pressure
adjusting spring (6) will also make the valve stem
(11) move downwards slightly, and the main
valve control valve stem also generates one
small displacement. At the moment, the main
valve will output small-flow pressure oil, and this
pressure oil will make the working cylinder or
motor act slowly. However, when the pilot lever
suddenly swings by a large angle, the pressure
adjusting spring (6) will also make the valve rod
(11) move downwards quickly, the main control
valve rod will quickly generate one large
displacement to output large-flow pressure oil, so
that the working cylinder or motor quickly acts.
Therefore, the action speed of the cylinder or
motor is related to the control angle of the pilot
control lever.
The controllability depends on the action
sensitivity of the cylinder and motor. The timely
action of the cylinder and motor needs pilot
pressure oil to timely reach the main control
valve rod end and timely make the main control
valve rod act timely. The pilot lever swings in the
non-operative state, and only the pressure
adjusting spring (6) makes the valve stem (11)
move downwards. Actually, the downward
movement of the valve stem (11) firstly makes
the push rod (2), the spring (3) and the force
transmission rod (4) move downwards, and then,
the spring (3) and the pressure adjusting spring
(6) act together to make the valve stem (11)
move downwards. Therefore, the conduction
speed of pilot pressure oil is closely related to
these two springs, i.e. the controllability is closely
related to these two springs.
When the lever is released, the restoring spring
(7) makes the control lever return to the natural
non-operative state.
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

Maintenance References

Check items Maintenance limit Treatments Remarks

If one of them is
When the lever is neutral:
reached, the Conditions:
above 1000 cm³/min
Leakage volume pilot valve needs Primary pressure 2.94 MPa
During working: above 2000
to be replaced Oil viscosity 23mm²/s
cm³/min
with a new one.
The sliding section is abraded Replace the pilot In the aspect of leakage, the left condition is
Slide valve by 10 μm more than the non- valve with a new predicted to be roughly the same to the condition
sliding section one. with the above leakage.

The head is abraded by more

Push rod Replacement
than 1 mm.

The amount of clearance

Abrasion of
between the disk (302) of When shaking (clearance) is generated due to
operating section
operating section and the joint Replacement the looseness of the tightening section, etc.,
(amount of
section (301) is more than 2 adjustment is needed.
clearance)
mm.
Abnormal sounds, irregular
vibrations, too low primary Replace the pilot
Stability of action pressure, etc. are generated valve with a new
during working and cannot be one
restored after treatment

Note: although seals such as O-rings are expected to be replaced after removal, it doesn't matter to
reuse them after being confirmed undamaged.
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3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

3.3.2.6 Travel Pilot Valve Working Principle

The schematic diagram of the travel pilot valve
First side Maximum pressure 6.9 MPa (70 kgf/
pressure cm2)
Secondary Maximum control pressure 0~4.4 MPa
side pressure (0~44.8 kgf/m2)
Allowable 2
backpressure Maximum 0.3 MPa (3kgf/m )
Rated flow
10L/min
rate
Operating
±12.4°
angle
Mass 6.3kg
To obtain good responsibility, a pipeline
with about φ8 inner diameter and 3 m
Pipeline length is selected. Return oil shall not
be affected by other backpressures and
directly enter into tank.
To prevent the slide valve from being 1. Pedal
blocked due to uncleanness, please set 2. Pilot valve
Oil filter
oil filter with above 40 meshes at the T- fuel return port
entrance of port P. P- Oil inlet
Structure diagram for travel pilot valve

1. Pedal 1. Push rod 10.Oil port

2. Pilot valve 2. Spring 11.Cam adjusting group
T- fuel return port 3. Spring 12.Push rod
P- Oil inlet 4. Spring cavity 13.Pedal
5. Steel ball 14.Pressure spring
The travel pilot valve is composed of a pedal (1) 6. Damping piston 15.Oil port
and a pilot valve (2). Two control pedals 7. Spring holder T- oil interface
respectively control the left and right travel 8. Restoring spring P- oil interface
motors and share return port T and oil inlet port 9. Spool
P.
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

A hydraulic damping device is arranged inside To make sure the mechanical travel moves
this valve. When the machine is operated to stably, pilot oil pressure reaching the travel
move forwards or backwards and the road is control valve stem control port needs to be
bumpy, machine vibration is easily caused, so stable, i.e. oil pressure coming out of the oil port
the driver’s operation must be affected, and the (10) needs to be stable, which is realized by the
driver cannot operate well to make the machine pressure-reducing valve composed of the Spring
vibrate more severely to form a vicious circle. holder (7), the spring (14) and the spool (9).
The controllability of travel pilot valve without this
When the oil pressure of the oil inlet joint P rises,
device is poor, and the driver always has no
the pressure of the oil port (10) will also rise
choice but to stop the machine to eliminate
within a short period of time. Because the oil
machine vibration.
pressure of the oil port (10) rises, the force
The hydraulic damper is composed of a spring making the spool (9) move upwards increases,
(2), a spring (3), a spring cavity (4), a steel ball so the pressure adjusting spring pushes the
(5) and a damping piston (6); and the pressure- spool (9) upwards to reduce the communication
reducing valve is composed of a spring holder amount between the port P and the oil port (10).
(7), a spring (14) and a spool (9). Because the communication amount between
the port P and the oil port (10) is reduced,
When the travel pedal presses leftwards as
damping increases, i.e. the pressure drop from
shown in the figure, the cam adjusting gp (11)
the port P to the oil port (10) increases, and the
tilts to press the push rod (12) downwards, the
pressure of the oil port (10) is ensured to be
push rod (12) moves downwards to drive the
unchanged, even when the pressure of the oil
damping piston (6) and the spring valve seat (7)
inlet joint P has rised. When the pressure of the
to overcome the resistance applied by the
oil inlet interface P decreases, the pressure of
hydraulic damper and the elastic forces of the
the oil port (10) will also decrease within a short
springs (8) and (14) to move downwards, and the
period of time. Because the oil pressure of the oil
pressure adjusting spring (14) forces the spool
port (10) decreases, the force making the spool
(9) to move downwards so the oil port (10) is
(9) move upwards decreases, so the pressure
communicated with the oil inlet joint P. When the
adjusting spring pushes the spool (9) downwards
oil port (10) is communicated with the oil inlet
to increase the communication amount between
joint P, pilot pressure oil enters along the oil inlet
the port P and the oil port (10), i.e. damping of
joint P, reaches the travel control valve stem
communication between the port P and the oil
control port through the oil port (10), and pushes
port (10) decreases, the pressure drop from the
the travel control valve stem so that high
port P to the oil port (10) decreases, and the
pressure oil from the main pump flows across the
pressure of the oil port (10) is ensured to be
travel control valve stem to the travel motor. The
unchanged, even when the pressure of the oil
travel motor rotates to drive the mechanical
inlet joint P has decreased.
travel to move.
The travel control valve rod makes low pressure
oil at the other end flow back the oil port of the
travel pilot valve (15), the pressure adjusting
spring is not stressed due to the action of the
return spring, the spool is also in the upper
position, and the oil port (15) is communicated
with the return interface T at the moment. Low
pressure oil enters to the oil port (15) enters the
return cavity along the oil port (15) and returns to
the system oil tank from the return interface T.
3-74
3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

Fault Causes and Countermeasures

It is not easy to locate the fault. Problem points to be considered in several aspects are listed in the table
below. Because this valve is difficult to repair, please refer to the cause and countermeasure columns in
the table.

Symptom Reason Treatments

Insufficient primary pressure Ensure primary pressure
The elastic force of the spring (324)
for setting secondary pressure has Replace with new one
been weakened.
Low secondary pressure The clearance between the slide valve
Replace slide valve and valve body
and the valve body has been
group
abnormally large.
Remove, assemble and replace
Control parts are loose
control parts
Sliding parts are jammed Repair jammed parts
Variation in oil circuit pressure of oil Directly return the return oil to the oil
Unstable secondary pressure tank tank
Operate repeatedly for several times
Air in the pipeline
to exhaust air
Directly return the filling oil to the oil
Too high oil tank oil circuit pressure
High secondary pressure tank
Sliding parts are jammed Repair jammed section
Operate repeatedly for several times
Air remained in the plunger chamber
to exhaust air
Sliding parts are jammed Repair jammed section
The elastic force of the buffering
spring (336 and 337) has been Replace with new one
weakened.
Ineffective buffering The clearance between the buffering
Replace the buffering plunger and
plunger (224) and the buffering
buffering hosing group
housing has been abnormally large.
Check the check valve section after
Poor action of check valve
disassembly.
The damping hole of the buffering
Replace the buffering plunger
plunger has been abnormally large.
Sliding parts are jammed Repair jammed parts
Heavy buffering torque The damping hole of the buffering Replace or repair the buffering
plunger has been blocked plunger
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

3.3.2.7 Four-step Solenoid Valve

1. Maximum working
7.0MPa 12. Electrical specification
pressure
2. Allowable back
Below 1.0 Mpa (1) Solenoid valve type Oil immersed type
pressure
Reversing valve – 16 L/ JIS C 3214 Class-H
(2) Coil insulation type
3. Maximum flow min (180°C)
(Equivalent to 1 spool) Proportional valve – Tyok Electronics Japan
10L/min (3) Connector type
Econoseal J Series
Reversing valve -70cm³/
4. Leakage min 12-1 Solenoid directional
Specifications
(Equivalent to 1 spool) Proportional valve – 125 valve
cm³/min
Equivalent to JIS D 0203
5. Waterproofness (1) Rated voltage DC 24 V
S2
JIS D 1601-1995
(2) Allowable voltage
6. Vibration resistance Category 3 Class B 20.4~30 V
fluctuation range
Grade 70
Equivalent to ISO Less than 17W (at 24V and
7. Working oil (3) Rated power consumption
VG32~68 20°C)
8. Oil temperature Diode (equivalent to
-20~90°C (4) Overvoltage limiter
applicable range Hitachi U05E)
10. Allowable pollution
Below NAS Level 10 (5) Continuous rating Below 29V
degree
12-2 Electro-hydraulic
11. Interface JIS B 2351 G1/4 proportional pressure- Specifications
specifications reducing valve
JIS B 2351 G3/8 (1) Rated power 700mA
(2) Coil resistance 17.5 Ω (at 20°C)
3-76
3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

Structure diagram of four-step valve

1 2

5 4

1. Valve body 4. Oil return port T

2. Solenoid valve 5. Oil outlet port A
3. Oil inlet port P
Schematic Diagram for four-step valve

This valve is composed of four switch-type solenoid valves, which are respectively A1~A4. A1~A4
solenoid valves share oil inlet port P and oil return port T, according to electronic control signals, A1~A4
output pressure oil is connected with return oil T.
 3-77
December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

Fault Cause and Treatment of Quadruple Solenoid Valve

No. Symptom Reason Treatment
(1) The supply voltage is too (1) Confirm that the voltage of the electrical wiring
low reaches the specified value

(2) Replace the reversing valve coil

Note: Whether the voltage is too high?
(2) The solenoid valve is burnt
Whether the polarity of the solenoid valve is
The spool of the contrary?
1 solenoid valve can not
(3) Clean or replace the spool/valve bushing of the
be changed
(3) The spool is stuck reversing valve (confirm the cleanliness of the
operation oil)
(4) The pressure is over high (4) Decrease the pressure to the correct value

(5) The flow is too large (5) Decrease the flow to the correct value

(1) The O-ring is damaged (1) Replace the O-ring

Oil leaks out from the
2
solenoid coil (2) The gasket nut is damaged (2) Replace the damaged gasket nut

3.3.2.8 Travel Motor & Reduction Gear

Travel motor & reduction gear includes two sections: travel hydraulic motor (hereinafter referred to as
travel motor) and reduction gear, which will be described below respectively.

Travel Motor

Item Unit(s) GM60VA motor section

Motor stroke volume (high volume / low
cm³/rev. 290.7/170.1
volume)
Rated pressure Mpa 35.0
Maximum pressure (shock pressure) Mpa 41.2
Parking brake torque N·m More than 1171
Parking brake release pressure MPa Below 1.54
Common 0.2
Allowable oil discharge pressure MPa
Impact 0.69
Oil capacity of motor housing L 1.5
3-78
3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

Structure of travel motor

1. Housing 14.Cylinder block 28. Spring 39. O-ring 52 Gasket

2. Plug spring 29 M42 screw-plug 25 Throttle valve 53 Parallel valve pin
3. Oil Seal 15.Spring holder 30. O-ring (brake valve) 54 Plate
4. Locating ring 16.Ball joint 31 Pilot valve element 43. O-ring 55 Brake spring
5. Expansion plug 17.Shoe brake casing 44 Check valve 56 Hexagon socket
6. Tilt piston 18.Plunger group 32 Pin 45 Check valve spring bolt
7. Piston sealing 19.Meshing plate
33 Spring holder 46 Mthrottle valve 57. Safety valve
8. Steel ball 20.Friction plate
34. Spring 47. O-ring 58. Connector
9. Drive shaft 23 D-ring (major
10.Bearing diameter) 35 Pilot valve plug 48 Throttle valve 59 retaining ring
11.Pivot 24 Motor rear cover 36. O-ring 49. O-ring 60 Plug
12.Swash plate 25 Plug 37 Connecting pipe 50. O-ring 61. O-ring
13.Cylinder block 26 Valve element 38 Plug 51. Bearing
casing group
27 Spring holder
 3-79
December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

The travel motor is composed of the following main components:

1. Drive group for transmitting rotation force;
2. Anti-slip parking brake in parking;
3. Variable mechanism for switching motor capacity;
4. Safety valve installed in motor rear cover;
5. Control valve component (balanced valve) having significance in controlling hydraulic oil circuit;
The above functions are detailed below:
1. Drive group
Both ends are located at the spline tooth groove of the main shaft (9) supported by bearings (10), (51),
the Cylinder block (13) is wrapped inside, and the Cylinder block (13) and the oil distribution plate (54)
are compacted together by the spring (14) and are installed in the motor rear cover (24). 9 plunger group
(18) slides along the face of the swashplate (12) while entering and exiting the cylinder block (13). The
shoe end face of the plunger group (18) is composed of a hydrostatic bearing, folding is carried out
without leaving the face of the swashplate (12) while folding resistance is reduced, the elastic force of
the spring (14) is transmitted to the spring holder (15), ball joint (16) and shoe brake (17), and the end
face of the plunger group (18) is pressed against the swashplate.
2. Parking brake
The meshing plate (19) and the friction plate (20) are alternately placed in the spline groove at the outer
ring of the cylinder body (13), and the piston brake (21) is pressed in the housing (1) through 14 brake
springs (22).
3. Variable-capacity mechanism
A pivot supporting the swashplate, a tilt piston (6) tilting around the swashplate (12) and the pivot (11) as
centers and a tilt brake (1-1) deciding the tilt position are placed in two hemispheric grooves on the
swashplate (12), the highest pressure among the pilot pressure of the pilot valve section and external
command of the oil pressure oriented tilt piston (6), the motor inlet pressure and the motor outlet
pressure is subject to oil pressure export, and the mechanism is composed of three check valves (44) for
transportation to the pilot valve.
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3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

4. Safety valve
Keep a metal-sealed valve seat (57-2) in the inner hole section of the motor cover (24), tighten the
socket (57-1) fixed on the motor cover (24), insert the valve (57-3) for cooperating the valve seat (57-2)
with the inner hole of the socket (57-1) into the connecting plunger (57-4) from the inner hole of the valve
(57-3) to the oil circuit of the pilot body (57-6) through the adjusting spring (57-6), and also insert the pilot
body (57-6). It is composed of a plunger (57-7) pressed by the plug (57-5) and a shim (57-5) used for
spring adjustment.

57-1 Socket 57-5 plug screw 57-8 Gasket 57-11 support ring
57-2 valve 57-6 Pilot part body 57-9 Adjusting spring 57-12 O-ring
57-3 valve seat 57-7 plunger 57-10 O-ring 57-13 support ring
57-4 connecting plunger
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

5. Brake valve
Spool switching pressure: 0.59 ~ 0.95MPa
Check valve opening pressure: 0.015MPa
Section view of brake valve

Check valve

(1) Spool
Shut off oil discharge from hydraulic motor according to the switching of the spool group (26),
automatically exert countercurrent action, and hold the action effects of acceleration, stop and balance
on the hydraulic motor.
(2) Check valve (hidden in spool)
This valve is located in the oil supply passage of the hydraulic motor and also exerts the oil discharge
locking function. Therefore, this valve not only plays a role as a suction valve, but also can act on the
travel motor as a holding valve.
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3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

Travel motor interface and rotating direction

Entry guide
position

Motor main shaft rotating

Oil outlet
Oil inlet direction
(Seeing from motor cover side)
VB VA Right (clockwise)
VA VB Left (counterclockwise)
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

Working Principle

1. Action Principle of Travel Motor

High pressure hydraulic oil sent from the hydraulic pump enters from the oil inlet port (AV and VB) and
flows into the port through the brake valve component, motor cover (24) and oil distribution plate. The
rotating directions of the oil outlet port and output shaft are shown in the table above.

(a) (b)

LG922E930E03101

This high pressure oil is shown in the figure above and acts on each plunger within the range of Y-Y axis
180° from top dead center and bottom dead center of the connecting plunger.
F1=P×A (P: pressure, A: plunger area)
This force F1 becomes axial force F2 and radial force F31~F34(or F35 ) (see above figure (b) )
according to the swashplate with angle of inclination a, and the radial force acts as turning force at Y-Y
axis and generates
T=r1·F31+r2·F32+r3·F33+r4·F33 Torque
(Add r5·F35 while 5 plungers apply the high pressure. )
This torque is transmitted to the spline of the main shaft (9) through the cylinder block (13) and is finally
transmitted to the main shaft (9).
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3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

2. Working Principle of Parking Brake

When high oil pressure selected by the balanced component directly assembled in the motor cover (24)
acts on the piston brake (21), the parking brake is loose. Braking torque will always exist when no
pressure acts. This braking torque is generated by the friction force between the meshing plate (19)
inserted in the housing (1) and the friction plate (20) and is transmitted to the cylinder block (13) through
the spline of the cylinder block.
When no pressure acts on the piston brake (21), the piston brake (21) is supported by the brake spring
(55), and the piston brake pushes the meshing plate (19) and the friction plate (20) towards the housing
(1). The generated friction force pushes the self-rotating cylinder block (13) to drive the main shaft (9) to
generate braking torque.
Structure of brake valve
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

3. Working Principle of Variable-capacity Mechanism

If the pressure greater than the spring (34) is input on the high-speed travel command Pa, the spring will
be compressed, and the spool (31) will move rightwards. So P and C are conducted. The highest
pressure among the motor pressure MA, MB and high-speed travel command is selected to be guided
into the tilt piston (6) through the check valve (44). Therefore, the swashplate (12) will tilt as an imaginary
line along the axis of L line connecting 2 pivots (11) until touching the tilt baffle block (1-1). As a result,
the import and export of the piston (18) will decrease, and the capacity of the motor becomes small. The
motor can operate at high speed without increasing the oil flow of the oil pump. At the moment, the
capacity ratio of this model is 1.71 times.
On the contrary, if the pressure on the high-speed travel command Pa is zero, the spool (31) will return
to left under the force of the spring (34), oil guided into the tilt piston (6) will return to the oil tank through
the throttle valve (46), and the thrust disappears.
9 pistons (18) are evenly distributed on the swashplate (12) to press the swashplate (12). The acting
point of the converged force is almost in the center of the swashplate (12), as shown in the figure. The
pivot (11) is in the position deviating the center S. The rotating force generated by S and piston makes
the swashplate return to the original position, and the machine travels at low speed.
If the specified pressure is exceeded, the counterforce of the pin (32) will make the spool (31) return to
left. Oil pressing the tilt piston (6) will return to the oil tank. The swashplate becomes tilting, the motor
capacity becomes large, and low-speed travel is restored. Once this pressure is lower than the setting
pressure, the spool (31) will return to right, and the machine travels at high speed.

Point of
strength
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3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

4. Working Principle of Safety Valves

Two safety valves are configured in a cross way and have the following functions.
(1) When the hydraulic motor is stopped, the braking pressure generated at the motor output side is held
below a certain valve in order to prevent load inertia.
(2) When the hydraulic motor is started, it is driven by the setting pressure. Hold quick acceleration.
During stop, the generated pressure is held at low pressure for short time in order to relieve braking
impact. The circuit pressure is held at the specified setting pressure in order to achieve smooth meshing
of reduction gear, track sprocket section, etc., i.e. boost buffering action.
When the travel motor is stared, if the pressure at the port A of the safety valve rises, this pressure acts
on the connecting piston (57-4) inside the valve through the small hole of the valve (57-2) while acting on
the effective diameter section of the valve seat (57-3) of the valve (57-2), it rises to the port A pressure,
and the valve (57-2) resists the adjusting spring (57-9) through the area difference between the effective
diameter section of the valve seat and the hole diameter section of the connecting piston to reach the
specified setting pressure.
When the travel motor is braked, the piston (57-7) at the rear is located at the left side due to driving
pressure. If the port A pressure rises, the pressure acts on the piston (57-7) through the small hole of the
valve and the small hole of the connecting piston (57-7), and the piston will move rightwards until
touching the housing. During this time, the valve (57-2) holds the port A pressure resisting the adjusting
spring (57-9) at relatively low pressure, and oil is discharged from the port B side. After the piston (57-7)
touches the housing, it acts just like the motor is started.

Hole
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

5. Working Principle of Brake Valve

1. Holding state
When the switching valve is in neutral state, ports VA and VB are connected with the oil tank, and the
valve (26) is held in the central position by the springs at both ends. Therefore, the passages VA -> MA
and VB -> MB are closed. Ports MA and MB connected both sides of the hydraulic motor are also closed.
Moreover, the parking brake release passage is connected with the oil tank, and the parking brake
changes into the working state. The hydraulic motor stops rotating due to brake spring force.
If a torque greater than the brake spring force is generated, the parking brake will slip, holding pressure
will be generated at the port MA or MB side, and the hydraulic motor will slightly rotate due to the holding
pressure.
When the hydraulic motor slightly rotates, high pressure oil in the closed circuit will run away, and
cativation will be generated at the low pressure side of the closed circuit. The check valve built in the
spool is started to prevent cavitation, the passage VA -> MA or VB -> MB is formed to replenish oil
equivalent to leakage from the oil tank.

Spring Spring
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3.3.2 Hydraulic Element CLG930E/936E

2. During acceleration operation

The port VA is connected with the hydraulic pump, and the port VB is connected with the oil tank through
the switching of the switching valve. Pressure oil from the hydraulic pump enters from the port VA to
push open the check valve in the spool, and is supplied to the hydraulic motor from the port MA to make
it rotate.
Meanwhile, pressure oil enters the pilot valve chamber at the port VA side to overcome the spring force
at the port VB side, and the spool (26) will move leftwards. Therefore, when a return passage MB -> VB
is formed, pressure oil will also be supplied to the parking brake passage, the parking brake is released,
and the motor starts to operate.
The inertia load of the travel motor is great, pressure required for acceleration reaches the setting
pressure of the safety valves, and the pressure of the hydraulic motor is relieved while the rotating speed
increases.
As the motor speed increases, leakage will decrease, and the motor finally reaches the rated speed.

Pilot chamber Pilot chamber

Spring Spring
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CLG930E/936E 3.3.2 Hydraulic Element

3. When operation is stopped

The switching valve returns to the central position to cut off oil supply in the rotation midway of the
hydraulic motor. The ports VA and VB are communicated with the oil tank. The valve chambers at both
ends of the spool (26) have the same pressure, and the spool returns to the neutral position due to the
force of the spring (28).
Therefore, the passage MB -> VB is closed. However, the hydraulic motor will continue rotating due to
the inertia force of the load, and plays a role as a pump to constantly discharge hydraulic oil from the port
MB. However, the pressure will rise because the passage is closed, the safety valves operate, and the
hydraulic motor constantly decelerates until stop finally.
Even the parking brake release pressure slowly decreases due to the throttle valve, the brake finally
takes effect, and the rotation of the hydraulic motor is mechanically stopped.

Pilot chamber Pilot chamber

Spring Spring
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3.3.2 Hydraulic Element CLG930E/936E

4. When balanced valve works

The balanced valve needs to take effect in order to decelerate the hydraulic motor which rotates due to
load inertia.
If pressure oil supplied from oil port pressure pump to the port VB constantly decreases, the hydraulic
motor itself will rotate in excess of the supply amount due to inertia, the pressure in the pilot valve
chamber at the port VB side will decrease, and the spool (26) will be pushed to left due to spring force
(28) and moves towards the neutral position.
Therefore, the area of the passage MA -> VA decreases, and the passage resistance increases. The
pressure at the MA side rises, and the hydraulic motor is under braking action.
If the hydraulic motor decelerates to below the rotating speed equivalent to the oil supply amount, the
pressure in the pilot valve chamber at the port VB side will rise, and the spool (26) will move to right. The
area of the passage MA -> VA increases, and the braking action decreases. The rotating speed of the
hydraulic motor is controlled to be equivalent to the oil supply amount.
Throttle valves having damping effect are configured in the pilot valve chambers at both ends of the
spool in order to make the balanced valve work stably.
When the balanced valve plays the action of adjusting pressure, the parking brake is released.

Check valve Check valve

Pilot chamber Pilot chamber

Spring Spring
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

Maintenance References of Travel Motor

1. Replacement standards of friction parts

When the abrasion degree of each friction part exceeds the following standard, it shall be replaced or
readjusted. However, when the appearance of any part has obvious damages, it shall be replaced in
advanced without limitations of this standard.

Replacement
Standard
Item Schematic recommended Handling method
size (mm)
value (mm)

Clearance between plunger Replace the plunger

0.027 0.052
and cylinder bore (D-d) or cylinder

Looseness (δ) between

Replace the plunger
plunger and skid shoe 0 0.3
and skid shoe group
riveting section

Replace the plunger

Thickness of skid shoe(t) 5.5 5.3
and skid shoe group

Thickness of friction plate - 2.0 1.8 Replacement

1. Maintenance standards of rotation meshing surfaces

When the roughness on the rotation meshing surface of each section exceeds the following standard, it
shall be trimmed or replaced.
Part name Standard roughness Roughness requiring trimming
Skid shoes 0.8-Z(Ra=0.2)(abrading) 3-Z(Ra=0.8)
Plunger 0.4-Z(Ra=0.1)(abrading) 3-Z(Ra=0.8)
Cylinder 1.6-Z(Ra=0.4)(abrading) 12.5-Z(Ra=3.2)
Valve plate 0.8-Z(Ra=0.2)(abrading) 6.3-Z(Ra=1.6)

Notes: 1. The roughness of each rotation meshing surface is controlled to be lower than the standard
roughness through grinding.
2. When the spherical meshing section between the plate spring and cylinder is rough, the complete set
of group shall be replaced.
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3.3.2 Hydraulic Element CLG930E/936E

Working Principle of Reduction Gear At the moment, because the support K2 is fixed
on the car body, the gear d transmits power to
The reduction gear weakens the rotating speed the annular gear ring, and the annular gear ring a
transmitted by the hydraulic motor and converts rotates.
it into strong rotating force. This reduction gear
adopts double planetary gear reduction
mechanism.
The planetary mechanism is composed of sun
gears, planetary gear (planetary) supports and
an annular gear ring. After the sun gear (s) at the
force entry side rotates, the planetary gear
rotates on its axis and is simultaneously meshed
with the fixed annular gear to make revolution
movement. Revolution movement is transmitted Secondary-level
to the support (k) to transmit torque. reducing mechanism

The figure below shows the structure of the

planetary gear.

Fixed annular gear ring Maintenance References of Reduction Gear

Planetary gear
Whether the reference scan be reused once
Support again is defined according to measurement
values in component disassembly. However,
these are general references. If the component
Input Output appearance has obvious bruises or color
Sun gear changes for property before disassembly, the
range of switching components is preferentially
decided according to the disassembly purpose
and the expected residual life.
Annular gear ring

Support

Sun gear

Planetary
pinion

Planetary gear structure

In the figure below, after the sun gear (S1) at the

force entry side rotates, planetary movement
between gears S1, a, and b is caused, and the
revolution of the gear b transmits the entry force
of the support K1 to the second sun gear S2 to
cause planetary movement between gears S2,a LG922E930E03115
and b.
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CLG930E/936E 3.3.2 Hydraulic Element

Symb
Item Reference value Allowable value Treatments
ols
Abrasion of planetary Smooth and no abnormal
A —— Replace 3 as one group
main shaft wear and sintering.
There is no chips and
Tooth face · tooth crown Smooth and no abnormal Replacement (3 planetary
B cracks more than
state wear and sintering. gears as one group)
Φ1.6mm
Axial clearance of inner
Above -0.08 mm
C race of angular contact —— Shim adjustment
less than 0.02mm
bearing (2)
Thickness of thrust shim
D 3.5±0.2mm 0.1mm abrasion Replacement
1 (18)
Thickness of thrust shim
E 5.5±0.2mm 0.1mm abrasion Replacement
2 (11)
Thickness of thrust plate
F 4.5±0.16mm 0.15mm abrasion Replacement
(23)
G Gear oil 500 hours at start, 1.000 per hour at second start Replacement

3.3.2.9 Swing Motor and Reduction Gear

The swing motor & reduction gear includes a rotary hydraulic motor (hereinafter referred to as swing
motor) and a reduction gear.
Model M5X180
3) 180.1
Displacement (cm
Working pressure(Mpa) 26
Maximum speed (r/min) 1550
Output torque (N.m) 745
Maximum parking torque (N.m) 967
Releasing parking pressure(Mpa) 2.7
Weight (kg) 67.5
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3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

Swing Motor

1. Structure of Swing Motor

Hydraulic motor section diagram

LG922E930E03116

10 Piston 101 Drive shaft 161 O-ring 390 Nameplate 469 Screw plug
20 H2 valve body 111 Cylinder 162 O-ring 391 Pin 712 Brake spring
assembly 114 Spring bearer 163 O-ring 400 Anti-turnover 742 Brake block
31 Time delay valve plate 171 Hexagon socket valve 743 Isolation panel
33 Hexagon socket 123 Fixing plate head cap bolt 401 Hex screw 983 Plug
head cap bolt 124 Swashplate 301 H2 housing 443 Roller bearing 984 Plug
51 Relief valve 131 Valve fixing plate 351 H2 piston 444 Roller bearing 985 Plug
80 Seal package 151 Screw plug 355 H2 spring 452 Pin
100 Valve body
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CLG930E/936E 3.3.2 Hydraulic Element

2. Working Principle of Swing Motor

1. Thrust plate 2. Plunger 3. Skid shoes 4. Swash plate 5. Cylinder block

When high pressure oil enters the cylinder block cavity through the oil port (a) (inlet of the thrust plate 1),
hydraulic pressure acting on the plunger generates axial force F. Pressure F
Pressure F acts on the shoe (3) through the plunger (2), and the shoe (3) acts on the swashplate (4)
through hydrostatic support. Force F1 vertically acts on the swashplate (4), and force F2 vertically acts
on the cylinder center. Force F2 is transmitted to the cylinder block (5) through the plunger and causes
rotation movement around the cylinder block. Because there are (9) equally arranged plungers inside the
cylinder block, the rotating moment will be successively transmitted to the cylinder drive shaft through
several plungers connected to the high pressure oil port. When the direction of oil flow is opposite, the
direction of the cylinder is also opposite.
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3.3.2 Hydraulic Element CLG930E/936E

1. Control Valve
Air suction preventing check valve

1. Control valve 2. Oil filler pipe 3. Oil check valve

In order to prevent insufficient oil supply when the motor works, hydraulic oil in the oil tank can directly
enter the swing motor through the oil replenishing line (2) and the oil replenishing check valve.
2. Relief valve
During the acceleration or braking process of the swing motor, the relief valve is opened and the
pressure of the swing circuit is held at a constant value. A small buffering piston is arranged in the relief
valve, and acts within short time after the relief valve starts to work and holds the pressure of the swing
circuit at a relatively small value. Therefore, a relatively mild acceleration and braking process can be
obtained.
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CLG930E/936E 3.3.2 Hydraulic Element

Braking of swing motor

1. Hydraulic oil cavity 111 Cylinder block 712 Brake spring

2. Hydraulic oil acting force 301. Housing 742 Friction plate
3. Spring action force 702. Brake plunger 743. Release plate
101 Drive shaft

The Cylinder block (111) is connected with the drive shaft (101) through one gear, and the friction plate
(742) is connected with the outer side of the cylinder block through one gear. When the brake spring
(712) acts on the friction plate 742 through the separation pad (743) and the brake plunger (702), friction
force is generated between every two of the friction plate, housing, separation pad and brake piston.
This friction force acts on the drive shaft to exert braking action on it.
On the other hand, when the unlock pressure enters the cavity formed between the brake plunger and
the housing, the hydraulic oil pressure overcomes the spring force to make the brake plunger move; the
friction plate and the housing are separated to release the brake.
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3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

3. Maintenance References of Swing Motor

1. Replacement Standards of Friction Parts

When the abrasion degree of each friction part exceeds the following standard, it shall be replaced or
readjusted. However, when the appearance of any part has obvious damages, it shall be replaced in
advanced without limitations of this standard.
Replaceme
nt
Standard Handling
Item Schematic recommen
size (mm) method
ded value
(mm)

Clearance between plunger and Replace the plunger

0.027 0.052
cylinder bore (D-d) or cylinder.

Looseness (δ) between plunger Replace the plunger

0 0.3
and skid shoe riveting section and skid shoe group.

Replace the plunger

Thickness of skid shoe(t) 5.5 5.3
and skid shoe group.

Thickness of friction plate - 2.0 1.8 Replace it.

2. Maintenance Standards of Rotation Meshing Surfaces

When the roughness on the rotation meshing surface of each section exceeds the following standard, it
shall be trimmed or replaced.

Part name Standard roughness Roughness requiring trimming

Skid shoes 0.8-Z(Ra=0.2)(abrading) 3-Z(Ra=0.8)
Piston shoe 0.4-Z(Ra=0.1)(abrading) 3-Z(Ra=0.8)
Cylinder 1.6-Z(Ra=0.4)(abrading) 12.5-Z(Ra=3.2)
Valve plate 0.8-Z(Ra=0.2)(abrading) 6.3-Z(Ra=1.6)

Notes: 1. The roughness of each rotation meshing surface is controlled to be lower than the standard roughness through
grinding.
2. When the spherical meshing section between the plate spring and cylinder is rough, the complete set of group
shall be replaced.
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

Reducer

1. Structure of Reduction Gear

The reduction gear is composed of double planetary gears.

The tooth number of each gear is shown in the table below, and the total drive ratio is 21.78. I.e. the
rotating speed of the hydraulic motor is transmitted to the output shaft in 1/21.78. The output shaft is
consistent with the rotating direction of the output shaft. The gear and the transmission ratio of the
reduction gear are as the following table:
Sun gear Planetary gear Inner gear Transmission ratio
First level 18 23 66 i1=4.666
Second level 18 23 66 i2=6.666
Total transmission ratio i1×i2=21.78

102 Valve body D2 231 No.1 carrier D 601 hexagon head bolt 909 Pin
104 Rear axle cover E 282 No.2 pin B 602 Hexagon socket head 910 Pin
201 Drive shaft B 283 No.1 pin B cap bolt 912 snap ring
202 Gear ring E 284 Push plate E 801 oil seal 913 snap ring
203 No.2 planetary gear D 390 Nameplate 802 O-ring 915 Bearing seal ring
204 No.2 sun gear D 391 Pin 903 Screw plug 922 Screw plug
210 No.1planetary gear D 402 Self-aligning roller 904 Hexagon socket head 925 Exhaust valves
211 No.1sun gear D bearing cap bolt 926 Grease fitting
230 No.2 carrier D 403 Positioning pin plug 905 O-ring 930 Hex screw
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3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

2. Maintenance References of Reduction

Gear

Maintenance
Part Check Treatments
references
When the size of single
Sun gear pitting corrosion and
Planetary gear Pitting corrosion and dents on tooth surface dent is above φ1 mm or Replacement
Inner gear occupied 5% of total
area
Replacement
(Notice: Replace them
when the reduction gear
Oil seal Lip surface is damaged or abraded Damaged or abraded
is disassembled for the
purpose of inspection,
etc.)
Notice: Do not extract it from the drive shaft
1. Check whether the race surface and roller of
the bearing have pitting corrosion, abrasion, etc.
Support within the visible range. Replacement
bearing (front 2. Check whether dust caused by excessive (Note: Do not reuse
Abnormal condition
side) of drive abrasion exists in gear oil. bearing extracted from
shaft 3. Check whether excessive abrasion dust is the shaft.)
adhered between the roller and the cage.
4. Check whether it can smoothly rotate by
hand.
Drive shaft
Check whether the race surface and roller of the
bearing (rear Having pitting corrosion Replacement
bearing have pitting corrosion
side)
Slide bearing
Check whether planetary gear No.2 and pin
section of
No.2 of carrier group No.2 are loose in the Looseness is above 0.5 Replacement
planetary gear
peripheral direction.
No.2
Check whether the sliding face zone with the
Side plate type Having obvious bruises Replacement
sun gear No.2 has obvious bruises
Needle bearing
set and pin
No.1 for Check whether the rotation face has pitting Having pitting corrosion
Replacement
supporting corrosion and abrasion and abrasion
planetary gear
No.1

This reduction gear has few parts and adopts the design method that the life of each section is balanced,
i.e. although all parts can be supplied individually, it is necessary to replace all of them due to structural
or functional causes during replacement. These are shown in the table below. Please pay special
attention to them.
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CLG930E/936E 3.3.2 Hydraulic Element

Parts to be replaced simultaneously

20 40 40 20 23 28 28 91 21 23 28 28 28 28 40 90
Part Number
1 1 2 3 0 2 6 0 0 1 3 4 5 7 3 9

Braking self-aligning roller bearing

Braking self-aligning roller bearing

No.2 Planetary gear

Planetary gear No.1

Part

Thrust washer

Lateral plate
No.2 Carrier

Carrier No.1

Thrust plate

Thrust plate
Drive shaft

Pin gauge
Spring pin

Spring pin
Numb

No.2 Pin

Pin No.1
er Part name

201 Drive shaft — ○ ○

Braking self-
Parts 401 aligning roller △ — △
to be bearing
repla Braking self-
ced 402 aligning roller △ △ —
simul bearing
taneo
No.2 Planetary
usly 203 — △ ○ △ ○
gear
230 No.2 Carrier △ — ○ △ ○
282 No.2 Pin △ △ — △ ○
286 Thrust washer △ △ ○ — ○
910 Spring pin △ △ ○ △ —
Planetary gear
210 — △ ○ △ △ △ △ ○
No.1
231 Carrier No.1 △ — ○ △ △ △ △ ○
283 Pin No.1 △ △ — △ △ △ △ ○
284 Thrust plate △ △ ○ — △ △ △ ○
285 Lateral plate △ △ ○ △ — △ △ ○
287 Thrust plate △ △ ○ △ △ — △ ○
403 Pin gauge △ △ ○ △ △ △ — ○
909 Spring pin △ △ ○ △ △ △ △ —

Parts marked by ○ indicate parts to be replaced simultaneously compulsorily.

Parts marked by △ indicate parts to be replaced simultaneously at best

Inner and outer races in the roller bearing must be replaced simultaneously.
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3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

3. Fault Cause and Treatment

Overload Lighten the load

Inlet pressure of Damage of Replace the

swing motor rises reduction gear reduction gear

Parking brake of swing motor Confirm pressure relief

is not released and check the brake
part

Confirm relief of
command pressure

No rise of inlet pressure of swing motor

Swing motor has whirling Motor axle damage Replace swing motor

Damage of reduction Replace the reduc-

gear tion gear

Abnormalities of Confirm and handle

Swing motor has no whirling pump, valve, etc. the abnormal parts
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CLG930E/936E 3.3.2 Hydraulic Element

Forget to apply liquid seal

filling material Removal and apply again

Joint surface is loosened

Oil leakage from Remove, apply again and
because the bolt is not
junction surface assemble as specified
screwed with looseness, etc.

The joint surface is Replace parts and

damaged components

Oil leakage from Oil seal has been Remove the reduction
the shaft damaged gear and replace oil seal

Housing tempera- Gear oil is not filled or Confirm the oil

ture of reducer is oil level is too low level and fill to
too high specified amount

The amount of Fill the grease fully

grease is too little

The gear, bearing, Replace the

etc. have been reduction gear
damaged
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3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

3.3.2.10 Oil Cylinder

Structure figure of boom cylinder
Basic Functions

Hydraulic cylinder is one kind of hydraulic

actuating mechanism, and it converts hydraulic
energy supplied by hydraulic pump into huge
linear motion force, and changes the direction of
oil pressure through valve operation to realize
stretching of movement direction.
Its basic function is to convert the directions of
huge linear motion and movement.
The structural diagram of the cylinder is shown
below:

8. Arm cylinder
9. Cushion collar

Structural diagram of arm cylinder

1. Small cavity oil port 5. Piston rod

2. Big cavity oil port 6. Cushion collar
3. Boom cylinder 7. Piston
4. Cylinder body

10.Bucket cylinder
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

Working Principle Cushioning Process:

1. Cushioning of boom and bucket cylinder

Cushion device of boom and bucket cylinder

3 Boom cylinder
8 Arm cylinder
10 Bucket cylinder
1 Small cavity oil port 6 Cushion collar 11 Passage
Cylinder extension: pressure oil enters the large When the boom and bucket cylinder extends out
cavity, return oil enters the small cavity, pressure and the cushion collar (6) approaches to the end
oil acts on the big end of the piston, and the
of the extension stroke, the through-flow area of
piston moves towards the rod cavity so that the the passage (11) decreases, so that the
piston rod extends out. displacement of the cylinder decreases, and the
Cylinder retraction: pressure oil enters the small movement speed of the piston slows down and
cavity, return oil enters the small cavity, pressure reaches the stroke end slowly. The boom and
oil acts on the rod end of the piston, and the bucket cylinder is only cushioned during
piston moves towards the no-rod cavity so that extension.
the piston rod retracts. 2. Arm cylinder cushion:
Cylinder cushion device of boom and arm

2 The oil port of big cavity 9 Cushion collar

12 Passage
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3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

The extension of the arm cylinder is same to the 2. Because air is highly compressible, the
boom and bucket cylinder, as described above. residual air in hydraulic cylinder can affect its
When the arm cylinder retracts and the cushion operating.
collar (9) approaches to the end of the extension
stroke, the through-flow area of the passage (12)
decreases, so that the displacement of the
cylinder decreases, and the movement speed of
If the hydraulic cylinder with air not emptied
the piston slows down and reaches the stroke
needs to be quickly operated or pressurized,
end slowly. The arm cylinder is cushioned during
because high heat generated by adiabatic
extension and retraction.
compression of air will cause seal burn-out,
Precautions on loading,transport leakage generated inside the hydraulic
cylinder cannot maintain the load, etc., and
1. Hydraulic cylinder must be transported there is a possibility of major accidents.
horizontally, and placed on wood block, and it
is better to use original packaging if possible. For air exhaust of hydraulic cylinder, please
refer to "Air exhaust of various devices" in
2. Impact, collision, etc. are not allowed during
"Test and adjustment" chapter.
the process of storage and transportation.
The surface of exposed piston rod and other )

assembly must be protected properly. Periodic maintenance

3. Using soft strap to avoid damaging surface
Lubricant shall be applied on hydraulic cylinder,
coating.
such as swing shaft, articulated point, pin, etc.
4. Strap distribution shall make lifting stable. periodically to prevent rust and stagnant
Use balance device if necessary. The center operation. After a new system is put into
of gravity of cylinder can be confirmed by operation, periodic check is necessary,
test.
The following points must be noted during check:
Precautions for use 1. Check oil port for leakage.
1. In order to guarantee hydraulic cylinder 2. Check piston rod for damage.
operates normally, working medium in 3. Frequently eliminate dirt, water, dust and
hydraulic cylinder must be fully filled. The grease, etc. on piston rod. However, do not
cleanliness of the medium must meet NAS clean dust ring and sealing parts with water,
level 8 as the minimum limit requirement. If and please use waste cotton yarn or cloth to
anti-rust oil needs to be mixed in working oil, wipe. Under the occasion of placing more
its oxidation or acidification degree must be than one week, please apply anti-rust oil on
detected. the surface of piston rod.
4. Periodically check sealing performance of
hydraulic cylinder, especially the joint
between piston rod and cylinder head for
leakage.
5. Periodically check and fasten the screws of
important parts (such as flange and oil pipe).
The dynamic seal in the hydraulic cylinder is
a quick-wear part. When internal leakage and
external leakage exceeds allowable values,
please contact LG local service agency.
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

3.3.2.11 Hydraulic Oil Tank Assembly

Structure
Exterior drawing of hydraulic oil tank

1. Hydraulic oil tank 5. Spring 9. Respirator 13.Plate

2. Return oil filter element 6. O-ring 10.Tank cover 14.Plug
3. Magnet 7. Washer 11.Suction element 15.O-ring
4. Cover 8. Bolt 12.O-ring 16.Level gauge
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3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

Distribution diagram of oil ports in tank body

I- Oil filler VI-Leakage oil return port in travel motor

II - Leakage oil return port in pump VIII-Auxiliary line oil return port
III - Oil drain port X-Pilot oil return port
IV - Oil suction port X-Back pressure oil return port
V-Dipstick position XI - Oil cooler oil return port
VI-Leakage oil return port in swing motor
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

1. Return Oil Filter 4. Level Gauge

Return oil filter is composed of a return oil filter Its function is mainly to reflect the oil level in the
element 7 and a bypass valve 6, the return oil tank and the oil range for the system. As shown
filter element 7 can filter out particles with overall in the figure, a safety oil level refers to the
size greater than 10 μmin oil so the oil keeps system oil level that is above the red line, and the
certain cleanliness. The bypass valve 6 plays the following indicates there is insufficient oil for the
action of protecting the return oil filter element 4. system.
When the filter element works for a period of time
and there are too may oil pollutants on its
surface, the liquid resistance passing through the
return oil filter element 4 will increase, the
bypass valve 6 will be opened during liquid
resistance pressure setting, oil directly returns to
the oil tank 8 without filtering, so that the damage
of the strainer of the return oil filter element 4 by Safe oil level: above red line
flushing can be avoided, and it can be used after
many times of cleaning. The system works under
this state, then the back pressure of the system
is too high, and unsuccessful oil return will cause
slow and powerless working. To avoid this
problem, the return oil filter element shall be
frequently cleaned or replaced.

2. Magnet

Effect of magnet:
1. Magnetize the oil tank;
2. Absorbing magnetizable solid particles in oil
together with the tank, which are mainly
some metal particles, such as the metal
powder particles formed due to the abrasion
between actuating mechanisms.

3. Air Filter

The respiratory system of the hydraulic system is

mainly composed of a tank and an air filter,
wherein the air filter is the respiratory passage of
the system, and its function is mainly to prevent
the air pressure in the hydraulic oil tank from
rising or dropping in the following case:
An air pressure change in the hydraulic oil tank
due to oil cylinder movement,
An air pressure change in the hydraulic oil tank
due to a temperature change.
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3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

Working principle

1. Suction element 7. Return oil filter element T-Pilot oil return

2. Pump 8. Tank Dr1-Dr2-Dr3-Dr6-Dr7 Main valve
3. Relief valve 9. Air filter return oil
4. Actuator Ch2-Check valve DrT-Leakage return oil in travel motor
5. Radiator Ch1-Back pressure valve DrS-Leakage return oil in swing motor
6. Bypass valve Drp-Leakage return oil inside pump

Oil suction process: the oil is drawn from the oil tank 8 oil suction port IV through the oil suction filter
element 1 to the pump 2.
Oil return process: Oil is transferred to the actuating mechanisms after being pressurized by the pump
2, then passes through the cooler 5 for cooling from the actuating mechanisms and flows to the oil port
XI or passes through the back pressure valve Ch1 and flows to oil port X, and returns to the tank 8, after
being filtered by the oil return filter element 7. When the system oil pressure is too high, part of oil passes
through the cooler 5 for cooling from the relief valve 3 or flows to the oil port X from the back pressure
valve Ch1, and returns to the tank 8 after being filtered by the oil return filter element 7. Oil passing
across the back pressure valve indicates return oil pressure is too high, which is caused by too high
liquid resistance flowing across the radiator 5.
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

3.3.2.12 PTO Pump

PTO gear pump adopts the internationally-used floating shaft sleeve structure with features of high
pressure, low noise, high efficiency and flexible installation.

Performance parameters
Model PGP517 Displacement ml/r 28
Rated pressure (bar) 250 Maximum pressure (bar) 275
Minimum speed (r/min) 500 Maximum speed (r/min) 3100
Input power (kW) (1500r/min) 19.3 Weight (kg) 8.5

Structure

No. Part Number Part name Quantity

1 CL3912883058 Oil Seal 1
2 3335020202B Front cover 1
3 CL3912882162 Support part 2
4 CL3912882161 Seals 2
5 CL3912185093 Shaft sleeve subassembly 2
6 CN103800220 Drive gear 1
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3.3 Hydraulic System December 30, 2017
3.3.2 Hydraulic Element CLG930E/936E

No. Part Number Part name Quantity

7 3332728000 Driven gear 1
8 GB/T119.2-6X14 Pin 2
9 CN103800219 Intermediate part 1
10 020153N0674 O-ring 2
11 3333000100 Rear cover 1
12 GB/T5782-M12X120-12.9 Bolt 4
13 3913782232 Washer 4
14 DF50-133 Sign 1
15 3911432004 Rivet 2

Maintenance references

1. Intermediate part
When the pump efficiency decreases too much and the intermediate part chamber cleaning is more than
0.127mm, replace the intermediate part. And check whether the set pressure of system safety valve is
too high and whether there is abnormal hydraulic impact to confirm the fault cause and then conduct
troubleshooting.
2. Gear
When the gear surface and end surface have obvious scratches, grooves and burrs which can not be
repaired, replace the gear. Or the wear is more than 0.051mm, replace the gear. And check the oil
cleanliness, check whether the input connection is normal and whether there is abnormal hydraulic
impact.
3. Drive gear
Replace the drive gear when the spline is worn or damaged. Replace the oil seal when the contacting
part wear with the journal is more than 0.051mm.
4. Shaft sleeve assembly
When the shaft sleeve surface has obvious scratches, cavitation, deformation, etc. or the it is worn too
much, replace the shaft sleeve. And check the oil cleanliness, check whether the suction oil is sufficient,
whether the input connection is normal and whether there is abnormal hydraulic impact.
5. Dowel pin
When the positioning pin or pin hole is damaged during removal and installation, or the matching
clearance is poor, replace the positioning pin or replace the parts matching with the positioning pin.
6. Seals
No matter when the pump is removed or installed, replace the O-ring, seal components, oil seal, etc. in
the pump.
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.2 Hydraulic Element

Precautions for use

1. Strictly ensure the oil cleanliness. The hydraulic system involved the pump in should have filter
device with filter fineness of less than 25μm.
2. Anti-wear hydraulic oil is recommended. At 40°C, the oil kinematic viscosity is 42~74mm2/s and
when using the oil, keep the oil temperature range of (-20~80)°C.
3. Elastic coupling is recommended to install the pump drive shaft and the prime motor output shaft with
coaxiality difference of less than 0.1mm; for the shaft sleeve coupling, the coaxiality difference
should be less than 0.05mm.
4. The pump suction oil level is not more than 0.5m.
5. The pump rotation direction can not be mistaken, that is, the pump oil inlet and outlet can not be
mistaken.
6. Avoid start or stop with load.
7. If the pump is not used for a long time, separate the pump with the prime motor to stop the pump.
When reusing the pump, do not apply the maximum load immediately and run with no load at low
rotating speed for not less than 2 minutes.
8. Inlet, outlet port shall be installed firmly and sealing device is secured, otherwise it may cause oil leak
or air suction, which will affect the pump's performance.
9. The highest pressure and maximum rotating speed mean the allowable peak values in a short period
during operation, which should be avoided for applying for a long time, otherwise, the pump service
life will be influenced.
10. Before operation, run the new pump or repaired pump with no load and conduct impact running for a
short time. Then check the working condition of the pump and no leakage, excessive heat and noise
is allowed.

Transportation and storage

1. Take protective measures for exposed thread oil port and input shaft.
2. The package should be firm, reliable and shockproof.
3. Avoid storage condition of high temperature and high humidity.

Fault Diagnosis

1. Symptom: Abnormal noise.

Solution: Check the rotation direction and whether the oil inlet and outlet are connected firmly and
correctly; check whether the input shaft and the locating flange are connected firmly and check whether
there is sir suction.
2. Symptom: There is crawling in the cylinder.
Solution: Exhaust the system and loosen relative connectors for exhaust if necessary.
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3.3 Hydraulic System December 30, 2017
3.3.3 Hydraulic Principle CLG930E/936E

3.3.3 Hydraulic Principle

3.3.3.1 Main Hydraulic Circuit

The main hydraulic circuit is the passage transmitting the hydraulic energy from the tank to the actuators.
The complete main hydraulic circuit includes: suction passage, drain passage, return passage and
leakage passage.

Suction passage

As the solid arrow shown in the following figure, the oil enters the hydraulic pump from the suction port of
the tank passing through the suction filter.

1. Hydraulic oil tank 2. Suction rubber hose 3. Suction steel tube 4. Main pump
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.3 Hydraulic Principle

Drain passage

7
6
8

9 1

4 3
5

1. P1 hose assembly 4. Left travel motor hose assembly 7. Arm cylinder hose assembly
2. P2 hose assembly 5. Boom cylinder hose assembly 8. Swing motor hose assembly
3. Main control valve 6. Bucket cylinder hose assembly 9. Right Travel motor hose assembly

As shown at the arrow, the oil pumped from the P1 pump enters the P1 port of the main control valve,
and the oil pumped from the P2 pump enters the P2 port of the main control valve. After being distributed
by the main control valve, the oil enters the actuators. The diagram only presents one of the oil flow
directions.
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3.3 Hydraulic System December 30, 2017
3.3.3 Hydraulic Principle CLG930E/936E

Return passage

1
2

3 6

1. Return passage 1 3. Check valve 5. Hydraulic oil tank

2. Return passage 2 4. Oil radiator 6. Check valve

All the return oil of the actuators returns to the hydraulic oil tank through the return passage. As shown
in the figure above, under normal conditions, a large amount of return oil flows from No.2 return passage
to the hydraulic tank 5 after passing through the check valve 3 and the oil cooler 4.
When a large amount of return oil passes through the oil cooler 4, as the return oil amount increases,
such as arm opening action. The return back pressure increases rapidly, to prevent the oil cooler from
being damaged by the increased pressure. The check valve 6 on the return passage 1 is opened. Return
passage 1 helps to shunt and prevent the oil cooler from damage.
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.3 Hydraulic Principle

Passage for oil drainage and swing motor oil replenishment

LG922E930E03138

1. Right travel motor 2. Left travel motor 3. Center joint

The drained oil at the lower part, which is absorbed to the upper part through the center joint 3, is mainly
from the two travel motors.

LG936E03018

1. Center joint 2. Swing motor 3. Main pump

The leaked oil at the upper part is mainly composed of three parts:
1. The leaked oil from the two travel motors is back to the tank through the center joint 1;
2. Oil drainage of the swing motor 2;
3. Oil drainage from the main pump 3.
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3.3 Hydraulic System December 30, 2017
3.3.3 Hydraulic Principle CLG930E/936E

3.3.3.2 Pilot Circuit

1. Pilot pump 3. Pilot valve group 5. Left hand pilot valve 7. Travel pilot valve
2. Hydraulic oil tank 4. Four-step solenoid valve 6. Right hand pilot valve 8. Main control valve
group
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.3 Hydraulic Principle

The pressure of the pilot loop is from the pilot pump 1, which sets the system pressure as 3.9MPa using
the build-in filter screen and relief valve.
The pilot oil flows out from the A3 port of the pilot pump 1, and enters the electronic proportional
pressure-reducing valve to carry out electronic control to the main pump power; at the same time, it
enters the accumulator passing through the filter of the pilot valve group 3 and the check valve. The
check valve can keep the pressure. The accumulator can place the work implement on a safe ground in
case of failure of the machine, stabilize the pilot system pressure and absorb the pulsation when the
machine is working, and supplement the system pressure drop timely when several actions act at the
same time;
The pilot oil which flows out from the pilot valve group 3 enters the P1 port of the four-step solenoid
group 4. The return oil of all the solenoids in the four-step solenoid group 4 flows back to the tank
through the T1 port. A1 pressure control pilot valve cut-off;A2 traveling control transmission;A3 control
flat ground mode;A7 control pressurization.
The pilot oil which flows out from the four-step solenoid valve A1 enters the left-hand pilot valve 5, right-
hand pilot valve 6, travel pilot valve 7 at the same time, and controls the valve rod of the main control
valve 8 by operating the pilot valves.
Left-hand pilot valve 5 controls the machine arm and the revolving action. Right-hand pilot valve 6
controls the machine boom and the bucket action. Travel pilot valve 7 controls the travel action of the
machine.
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3.3 Hydraulic System December 30, 2017
3.3.3 Hydraulic Principle CLG930E/936E

3.3.3.3 Negative Flow Control Circuit (with the Control Spool in the Neutral)
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.3 Hydraulic Principle

1. Center position passage 4. Relief valve 7. Negative flow control oil 10.Hydraulic oil tank
2. Oil return passage 5. Orifice 8. Oil return passage 11.Right pump
3. Negative flow control oil 6. Relief valve 9. Center position passage 12.Left pump

The negative flow control system is an energy saving system. When the system does not work, the
pressure oil output from the left pump (12) and the right pump (11) of the main pump enters into return
passage (2) and (8) and returns to the hydraulic tank (10) through the orifice (5) respectively after
passing through the neutral passage (1) and (9) of main valve, and at the same time, the feedback
pressure generated before flowing through the orifice (5) enters the negative flow control port of the main
pump respectively after passing through the line (3) and (7), which minimizes the swashplate swing
angle of the main pump to reduce the output flow of the main pump and then save the energy.
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3.3 Hydraulic System December 30, 2017
3.3.3 Hydraulic Principle CLG930E/936E

3.3.3.4 Negative Flow Control Circuit (with the Control Spool Moving)
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.3 Hydraulic Principle

1. Center position passage 5. Orifice 9. Center position passage 12.Left pump

2. Oil return passage 6. Relief valve 10.Hydraulic oil tank 13.Swing spool
3. Negative flow control oil 7. Negative flow control oil 11.Right pump 14.Check valve
4. Relief valve 8. Oil return passage

In case of any action, such as revolving, as shown in the figure above, the revolving spool (13) moves
toward the left with the action of the pilot pressure, the right pump output pressure of the main pump
flows through the check valve (14), the right position of the revolving spool (13) moves to the swing
motor, the original neutral passage (9) is closed by the revolving spool, the negative flow control line (7)
is minimized, and the right pump swashplate swing angle of the main pump increases to supply oil to the
swing motor; the left pump of the main pump keeps in the smallest swing angle with the action of the
negative feedback control pressure (3).
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3.3 Hydraulic System December 30, 2017
3.3.3 Hydraulic Principle CLG930E/936E

3.3.3.5 Boom Rising Working Circuit

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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.3 Hydraulic Principle

1. Boom cylinder 6. Pilot control oil line 11.Solenoid valve 15.Right pump
2. Boom cylinder big 7. Boom spool 1 12.Pilot valve group 16.Pilot pump
chamber oil pipe 8. Check valve 13.Tank 17.Boom spool 2
3. Boom cylinder small 9. Pilot control oil line 14.Left pump 18.Check valve
chamber oil pipe 10.Hand pilot valve
4. Boom lock valve
5. Pressure passage

When the hand pilot valve (10) handle is rotated backward, the pilot pressure reaches the port 4 of the
hand pilot valve (10) after passing through the solenoid valve (11) of the pilot valve group (12) from the
pilot pump (16), and reaches the control ports of the boom spool 1 (7) and boom spool 2 (17)
respectively after passing through pilot line (6) and (9); at the same time, the control oil in the right
control chamber of the boom spool 1 (7) flows back to the tank (13) after passing through spool (7) oil
pipe at the other end and the oil port 2 of the hand pilot valve (10); the boom spool 1 (7) and the boom
spool 2 (17) reverse to corresponding positions with the action of the pilot control pressure;
The pressure oil output from the left pump (14) of main pump reaches the big chamber of boom cylinder
(1) after passing through the check valve (8), boom spool 1 (7) and pressure passage (5) boom locking
valve (4); at the same time, the pressure oil of the right pump (15) after passing through the boom spool
2 (17), the check valve (18) merging into boom spool 1(7), spool reaches the big chamber of boom
cylinder (1); the oil in the boom cylinder (1) small chamber flows back to tank (13) after passing through
boom cylinder small chamber oil piping (3) and boom spool 1(7), thus, with the action of the pressure oil,
the piston rod of the boom cylinder stretches out to lift the boom.
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3.3 Hydraulic System December 30, 2017
3.3.3 Hydraulic Principle CLG930E/936E

3.3.3.6 Boom Descending Working Circuit

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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.3 Hydraulic Principle

1. Boom cylinder 6. Pilot control oil line 11.Solenoid valve 15.Right pump
2. Boom cylinder big 7. Boom spool 1 12.Pilot valve group 16.Pilot pump
chamber oil pipe 8. Check valve 13.Tank 17.Boom spool 2
3. Boom cylinder small 9. Pilot control oil line 14.Left pump 18.Check valve
chamber oil pipe 10.Hand pilot valve
4. Boom lock valve
5. Pressure passage

When the hand pilot valve (10) handle is rotated forward, the pilot pressure reaches the port 2 of the
right-hand pilot valve (10) after passing through the pilot valve group (12) and the solenoid valve (11)
from the pilot pump (16), and reaches the control ports of the boom spool 1 (7) and boom locking valve
(4) respectively after passing through the pilot line (9); at the same time, the control oil in the left control
chamber of the boom spool 1 (7) flows back to the tank (13) after passing through the hand pilot valve
(10) oil port 4, and the boom spool 1 (6) towards to right with the action of the pilot control pressure;
The pressure oil in the left pump of the main pump (14) flows through the check valve (8), the boom
spool 1 (7), and the small chamber oil pipe (3) of the boom cylinder to the small chamber of the boom
cylinder (1); the oil in the big chamber of the boom cylinder (1) flows through the boom cylinder big
chamber oil pipe line (2), boom locking valve (4), and the part return tank (13) of the boom spool 1 (7) to
the small chamber of the boom cylinder (1), and another part of the hydraulic oil joints in the small
chamber of the boom cylinder (1) after passing the check valve in the boom spool 1 (7). Thus, with the
action of the pressure oil, the boom cylinder makes the piston rod withdraw, pull the boom downward
and realize the function of return oil regeneration.
During the declining process, the boom spool 1 (7) has a certain amount of return oil, a certain pressure
still exists in the negative flow of the left pump (14), which minimizes the discharge capacity of the left
pump (14), and then the energy is saved.
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3.3 Hydraulic System December 30, 2017
3.3.3 Hydraulic Principle CLG930E/936E

3.3.3.7 Arm Stretching Working Circuit

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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.3 Hydraulic Principle

1. Arm cylinder 6. Arm spool 2 11.Solenoid valve 16.Pilot pump

2. Arm cylinder big chamber 7. Check valve 12.Pilot valve group 17.Regeneration control
oil pipe 8. Pilot control oil line 13.Tank valve
3. Arm cylinder small 9. Switching valve 14.Left pump 18.Arm spool 1
chamber oil pipe 10.Left hand pilot valve 15.Right pump 19.Pressure passage
4. Arm lock valve
5. Pressure passage

When the left-hand pilot valve handle is rotated forward, the pilot pressure reaches the port 2 of the hand
pilot valve (10) after passing through the pilot valve group (12) and solenoid valve (11) from the pilot
valve (16), and reaches the control ports of the arm spool 1 (18) and the arm spool 2 (6) respectively
after passing through the switching valve (9) and pilot piping (8); at the same time, the control oil in the
control chamber-rh of the arm spool 1 (18) and arm spool 2 (6) flows back to the tank (13) after passing
through the piping, switching valve (9), and the port 4 of the left hand pilot valve (10); the arm spool 1
(18) and arm spool 2 (6) reverse to corresponding positions with the action of the pilot control pressure;
The pressure oil output from the left pump (14) of the main pump reaches the small chamber of the arm
cylinder (1) after passing through the check valve (7), arm spool 2 (6), arm locking valve (4), and arm
cylinder small chamber oil pipe (3); at the same time, the pressure oil of the right pump (15) reaches the
arm spool 1 (18) and pressure passage (19) to joint after passing through the check valve; the pressure
oil of the arm spool 2 (6) reaches the small chamber of the arm spool (1) after passing through the arm
locking valve (4) and the arm cylinder small chamber oil pipe (1); the oil in the arm cylinder (1) big
chamber flows back to the tank (13) after passing through the arm cylinder big chamber oil piping (2),
arm spool 1 (18) and the arm spool 2 (6), thus, with the action of the pressure oil, the piston rod of the
arm cylinder withdraws to make the arm stretch out.
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3.3 Hydraulic System December 30, 2017
3.3.3 Hydraulic Principle CLG930E/936E

3.3.3.8 Arm Retraction Working Circuit (with Regeneration)

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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.3 Hydraulic Principle

1. Arm cylinder 6. Arm spool 2 11.Solenoid valve 16.Pilot pump

2. Arm cylinder big chamber 7. Check valve 12.Pilot valve group 17.Regeneration control
oil pipe 8. Pilot control oil line 13.Tank valve
3. Arm cylinder small 9. Switching valve 14.Left pump 18.Arm spool 1
chamber oil pipe 10.Left hand pilot valve 15.Right pump 19.Pressure passage
4. Arm lock valve
5. Pressure passage

When the left-hand pilot valve (10) handle is rotated backward, the pilot pressure reaches the port 4 of
the hand pilot valve (10) after passing through the pilot valve group (12) and solenoid valve (11) from the
pilot valve (16), and reaches the control ports of the arm spool 1 (18) and the arm spool 2 (5) and the
control port of the arm locking valve (4) respectively after passing through the switching valve (9) and
pilot piping (8); at the same time, the control oil in the arm spool 2 (6) and arm spool 1 (18) flows back to
the tank (13) after passing through the piping, switching valve (9), and the port 2 of the left-hand pilot
valve (10); the arm spool 1 (18) and arm spool 2 (6) reverse to corresponding positions with the action of
the pilot control pressure; the pilot pressure oil opens the reverse control valve of the arm locking valve
(4) at the same time to connect the control pressure of the arm locking valve and that of the tank, and
unlock the arm small chamber return oil.
The pressure oil output from the left pump (14) of the main pump reaches the big chamber of the arm
cylinder (1) after passing through the pressure passage, check valve (7), arm spool 2 (6), and the arm
cylinder big chamber oil pipe (2); at the same time, the pressure oil of the right pump (15) reaches the
arm cylinder (1) big chamber jointing the pressure oil of the arm spool 2 (6) after passing through the arm
spool 1 (18) and the arm cylinder big chamber oil pipe (2); with the light load, the regeneration control
valve (17) does not switch, and at this moment, the oil in the small chamber of the arm cylinder (1) flows
back to the arm spool 1 (18) after passing through the arm cylinder small chamber oil piping (3) and the
arm locking valve (4); a part of oil reaches the big chamber of the arm cylinder (1) after passing through
the internal check valve of the arm 1 (18) , another part of the oil flows back to the tank after passing
through the regeneration control valve orifice, this circuit can accelerate the moving speed, and the
function is called "regeneration". Thus, with the action of the pressure oil, the piston rod of the arm
cylinder stretches out to make the arm withdraw.
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3.3 Hydraulic System December 30, 2017
3.3.3 Hydraulic Principle CLG930E/936E

3.3.3.9 Arm Retraction Working Circuit (with no Regeneration)

 3-133
December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.3 Hydraulic Principle

1. Arm cylinder 6. Arm spool 2 11.Solenoid valve 16.Pilot pump

2. Arm cylinder big chamber 7. Check valve 12.Pilot valve group 17.Regeneration control
oil pipe 8. Pilot control oil line 13.Tank valve
3. Arm cylinder small 9. Switching valve 14.Left pump 18.Arm spool 1
chamber oil pipe 10.Left hand pilot valve 15.Right pump 19.Pressure passage
4. Arm lock valve
5. Pressure passage

With the heavy load, when the oil inlet pressure of the arm cylinder big chamber exceeds the set
pressure of the regeneration control valve (17) spring, the regeneration control valve (17) will reverse, at
this moment, the arm cylinder small chamber return oil can flow to the tank directly, and then the
"regeneration" function is unavailable.
When the left-hand pilot valve handle is rotated backward, the pilot pressure reaches the port 4 of the
hand pilot valve (10) after passing through the pilot valve group (12) and solenoid valve (11) from the
pilot valve (16), and reaches the control ports of the arm spool 1 (18) and the arm spool 2 (6) and the
control port of the arm locking valve (4) respectively after passing through the switching valve (9) and
pilot piping (8); at the same time, the control oil in left control chamber of the arm spool 1 (18) and arm
spool 2 (6) flows back to the tank (13) after passing through the switching valve (9), and the port 2 of the
left-hand pilot valve (10); the arm spool 1 (18) and arm spool 2 (6) reverse to corresponding positions
with the action of the pilot control pressure; the pilot pressure oil opens the reverse control valve of the
arm locking valve (4) at the same time to connect the control pressure of the arm locking valve and that
of the tank, and unlock the arm small chamber return oil;
The pressure oil output from the left pump of the main pump (14) reaches the big chamber of the arm
cylinder (1) after passing through the check valve (7), arm spool 2 (6) and the arm cylinder big chamber
oil pipe (2); at the same time, the pressure oil of the right pump (15) reaches the big chamber of the arm
cylinder (1) jointing the pressure oil of the arm spool 2 (6) after passing through the arm spool 1 (18) and
the arm cylinder big chamber oil pipe (2); the oil in the arm cylinder (1) small chamber connects and
flows back to the tank after passing through the arm cylinder small chamber oil piping (3), arm locking
valve (4) and the arm spool 1 (18), thus, with the action of the pressure oil, the piston rod of the arm
cylinder stretches out to make the arm withdraw.
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3.3 Hydraulic System December 30, 2017
3.3.3 Hydraulic Principle CLG930E/936E

3.3.3.10 Bucket Retraction Working Circuit

 3-135
December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.3 Hydraulic Principle

1. Bucket cylinder 6. Bucket spool 11.Solenoid valve 16.Pilot pump

2. Bucket cylinder big 7. Check valve 12.Pilot valve group 17.Center position passage
chamber oil pipe 8. Pilot control oil line 13.Tank 18.Check valve
3. Bucket cylinder small 9. Shuttle valve 14.Left pump 19.Shut-off valve
chamber oil pipe 10.Right hand pilot valve 15.Right pump
4. Pilot control oil line
5. Pressure passage

Operate the right-hand pilot valve (10) handle to make it rotate toward left, and the pilot pressure
reaches the port 1 of the hand pilot valve (10) after passing through the pilot valve group (12) and
solenoid valve (11) from the pilot pump (16), and reaches the control port of the bucket spool (6) after
passing through the pilot control oil line (8); at the same time, the pressure oil output from the hand pilot
valve (10) makes the shut-off valve (19) switch to left after passing through the shuttle valve (9) and the
pilot control line (4) to shut off the return oil of the right pump (15); and the control oil in the control
chamber-rh of the bucket spool (6) flows back to the tank (13) after passing through the piping and the
port 1 of right-hand pilot valve (10). With the action of the pilot control pressure, the bucket spool (6)
switches to the corresponding position;
The pressure oil of the left pump (14) reaches the big chamber bucket cylinder (1) after passing through
the check valve (7), bucket spool (6) and the bucket big chamber oil pipe (2); the oil in the small chamber
of the bucket cylinder (1) flows back to the tank after passing through the bucket cylinder small chamber
oil piping (3) and the bucket spool (6), thus, with the action of the pressure oil, the piston rod of the
bucket cylinder stretches out to make the bucket withdraw.
The pressure oil output from the right pump (15), together with the oil from the left pump (14), enters the
bucket spool (6) after passing through the neutral passage (17), check valve (18) and the pressure
passage (5) to realize the jointing inside the valve.
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3.3 Hydraulic System December 30, 2017
3.3.3 Hydraulic Principle CLG930E/936E

3.3.3.11 Bucket Stretching Working Circuit

 3-137
December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.3 Hydraulic Principle

1. Bucket cylinder 6. Bucket spool 11.Solenoid valve 16.Pilot pump

2. Bucket cylinder big 7. Check valve 12.Pilot valve group 17.Center position passage
chamber oil pipe 8. Pilot control oil line 13.Tank 18.Check valve
3. Bucket cylinder small 9. Shuttle valve 14.Left pump 19.Shut-off valve
chamber oil pipe 10.Right hand pilot valve 15.Right pump
4. Pilot control oil line
5. Pressure passage

Operate the right-hand pilot valve (10) handle to make it rotate toward right, and the pilot pressure
reaches the port 3 of the hand pilot valve (10) after passing through the pilot valve group (12) and
solenoid valve (11) from the pilot pump (16), and reaches the control port of the bucket spool (4) after
passing through the pilot line (8); at the same time, the pressure oil output from the port 3 of the hand
pilot valve (10) makes the shut-off valve (19) switch to left after passing through the shuttle valve (9) and
the pilot control line (4) to shut off the return oil of the right pump (15); and the control oil in the left control
chamber of the bucket spool (6) flows back to the tank (13) after passing through the piping and the port
1 of hand pilot valve-rh (10). With the action of the pilot control pressure, the bucket spool (6) switches to
the corresponding position;
The pressure oil of the left pump (14) reaches the small chamber bucket cylinder (1) after passing
through the check valve (7), bucket spool (6) and the bucket small chamber oil pipe (3); the oil in the big
chamber of the bucket cylinder (1) flows back to the tank after passing through the bucket cylinder big
chamber oil piping (2) and the bucket spool (6), thus, with the action of the pressure oil, the piston rod of
the bucket cylinder stretches out to make the bucket withdraw.
The pressure oil output from the right pump (15), together with the oil from the left pump (14), enters the
bucket spool (6) after passing through the neutral passage (17), check valve (18) and the pressure
passage (5) to realize the jointing inside the valve.
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3.3 Hydraulic System December 30, 2017
3.3.3 Hydraulic Principle CLG930E/936E

3.3.3.12 Left Swing Working Circuit

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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.3 Hydraulic Principle

1. Left hand pilot valve 8. Pilot control pressure 15.Return oil check valve 21.Swing motor & reduction
2. Switching valve piping 16.Swing motor oil gear
3. Pilot control oil line 9. Negative flow feedback supplement piping 22.Motor unlock piping
4. Pilot control oil line pressure piping 17.Swing logic valve 23.Time delay valve
5. Motor unlock control line 10.Pilot valve group 18.Swing spool 24.Motor unlock control line
6. Orifice 11.Tank 19.Swing motor A port piping 25.Center position passage
7. Solenoid valve 12.Left pump 20.Swing motor B port piping 26.Shut-off valve
13.Right pump
14.Pilot pump

When the left-hand pilot valve (1) handle is rotated to left, the pilot pressure reaches the port 1 of the
hand pilot valve after passing through the pilot valve group (10) and solenoid valve (7) from the pilot
pump (14), and reaches the control port of the swing spool (18) after passing through the pilot line (4); at
the same time, the control oil in the control chamber-rh of the swing spool (18) flows back to the tank (10)
after passing through the piping (3) and the oil port 3 of the left-hand pilot valve (1). With the action of the
pilot control pressure, the swing spool (18) switches to the corresponding position; at this moment, the
pilot pressure oil generates the pressure after passing through the piping (8), throttle valve (6) and the
swing spool (18) stops after reversing; the control pressure provided by the pilot valve group (10)
reaches the time delay valve (23) unlocked by the swing motor after passing through the pilot control
pressure piping (8), throttle port (6) and the motor unlock control piping (5) and (24), and pushes the
reverse valve of the time delay valve to reverse; the control pressure oil output from the pilot valve group
(10) enters the locking cylinder of the motor after passing through the motor unlock piping (22) to realize
the unlocking;
The pressure oil of the right pump (13) reaches the swing motor and & reduction gear (21) after passing
through the swing logic valve (17), swing spool (15), and the swing motor B port line (20); the oil of the
swing motor & reduction gear (21) A port flows back to the tank after passing through the swing motor A
port line (19) and the swing spool (18), thus, with the action of the pressure oil, the swing motor &
reduction gear drive the platform to rotate toward the left.
The pressure oil output from the left pump (12) of the main pump flows back to the tank after passing
through the neutral passage (25) and the shut-off valve (26); the front feedback pressure at the throttle
port acts on the variable mechanism of the left pump (12) through the negative flow feedback pressure
line (9), which minimizes the discharge capacity of the left pump (12).
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3.3 Hydraulic System December 30, 2017
3.3.3 Hydraulic Principle CLG930E/936E

3.3.3.13 Swing Priority Circuit

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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.3 Hydraulic Principle

1. Arm cylinder 6. Shuttle valve 11.Tank 15.Swing spool

2. Arm spool 2 7. Switching valve 12.Left pump 16.Rotary priority valve
3. Swing pilot control oil 8. Hand pilot valve 13.Right pump 17.Swing motor & reduction
passage 9. Solenoid valve 14.Pilot pump gear
4. Swing shuttle valve pilot 10.Pilot valve group 18.Arm spool 1
control oil passage
5. Arm pilot control oil
passage

The main function of the priority valve (16) is to distribute the pressure oil output to the swing spool (15)
and the arm spool 1 (18) by the right pump (13). As shown in the circuit diagram, the throttle passage is
at the right position.
When the left handle of the hand pilot valve (8) is operated at about 45° toward rear right, the pilot
pressure reaches the port 3 and port 4 of the left hand pilot valve from the pilot pump (14) after passing
through the pilot valve group (10) and the solenoid valve (9), and reaches the swing spool (15) and the
corresponding control ports of the arm spool 1 (18) and the arm spool 2 (2) after passing through the
switching valve (7) and the pilot piping (3) and (5) respectively. At this moment, the control oil of the
swing pilot control oil passage (3) reaches the pilot control port PSP of the swing priority valve (16) after
passing through the shuttle valve (6), which makes the valve move to the right throttle position.
The pressure oil output from the left pump (12) of the main pump reaches the big chamber of the arm
cylinder (1) after passing through the arm spool 2 (2).
At the same time, a part of the pressure oil of the right pump (13) reaches the swing motor (17) after
passing through the swing spool (15), and another part enters the arm cylinder (1) big chamber after
passing through the throttle passage-rh of the swing priority valve (16) and the arm spool 1 (18); as the
throttling action of the swing priority valve (16), the flow entering the arm spool 1 (18) is restricted, and
then the swing priority to the arm is achieved.
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3.3 Hydraulic System December 30, 2017
3.3.3 Hydraulic Principle CLG930E/936E

3.3.3.14 Right Swing Working Circuit

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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.3 Hydraulic Principle

1. Left hand pilot valve 8. Pilot control pressure 15.Return oil check valve 21.Swing motor & reduction
2. Switching valve piping 16.Swing motor oil gear
3. Pilot control oil line 9. Negative flow feedback supplement piping 22.Motor unlock piping
4. Pilot control oil line pressure piping 17.Swing logic valve 23.Time delay valve
5. Motor unlock control line 10.Pilot valve group 18.Swing spool 24.Motor unlock control line
6. Orifice 11.Tank 19.Swing motor A port piping 25.Center position passage
7. Solenoid valve 12.Left pump 20.Swing motor B port piping 26.Shut-off valve
13.Right pump
14.Pilot pump

When the left hand pilot valve (1) handle is rotated to right, the pilot pressure reaches the port 3 of the
hand pilot valve after passing through the pilot valve group (10) and solenoid valve (7) from the pilot
pump (14), and reaches the control port of the swing spool (18) after passing through the pilot line (3); at
the same time, the control oil in the left control chamber of the swing spool (18) flows back to the tank
(10) after passing through the piping (20) and the oil port 1 of the left-hand pilot valve (13). With the
action of the pilot control pressure, the swing spool (18) switches to the corresponding position; at this
moment, the pilot pressure oil generates the pressure after passing through the piping (8), throttle valve
(6) and the swing spool (18) stops after reversing; the control pressure provided by the pilot valve group
(10) reaches the time delay valve (23) unlocked by the swing motor after passing through the pilot
control pressure piping (8), throttle port (6) and the motor unlock control piping (5) and (24), and pushes
the reverse valve of the time delay valve to reverse; the control pressure oil output from the pilot valve
group (10) enters the locking cylinder of the motor after passing through the motor unlock piping (22) to
realize the unlocking;
The pressure oil of the right pump (13) reaches the swing motor and & reduction gear (21) after passing
through the swing logic valve (17), swing spool (18), and the swing motor A port piping (19); the oil of the
swing motor & reduction gear (21) B port flows back to the tank after passing through the swing motor B
port piping (20) and the swing spool (18), thus, with the action of the pressure oil, the swing motor &
reduction gear drive the platform to rotate toward the right.
The pressure oil output from the left pump (12) of the main pump flows back to the tank after passing
through the neutral passage (25) and the shut-off valve (26); the front feedback pressure at the throttle
port acts on the variable mechanism of the left pump (12) through the negative flow feedback pressure
line (9), which minimizes the discharge capacity of the left pump (12).
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3.3 Hydraulic System December 30, 2017
3.3.3 Hydraulic Principle CLG930E/936E

3.3.3.15 Travel Forward Working Circuit (Fast)

 3-145
December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.3 Hydraulic Principle

1. Left travel motor & 13.Travel pilot valve 25.Motor brake 37.Solenoid valve
reduction gear 14.Travel fast and slow gear 26.Control passage 38.Pilot return lines
2. Right travel motor & control line 27.Check valve 39.Four-step solenoid valve
reduction gear 15.B port pipeline, right 28.Transmission reversing group
3. Motor brake travel motor valve 40.Hydraulic oil tank
4. Unlock pressure oil 16.A port pipeline, right 29.Variable displacement 41.Pilot pump
passage travel motor cylinder 42.Left pump
5. Motor A port oil passage 17.Motor A port oil passage 30.Center revolving joint 43.Right pump
6. Balanced valve 18.Control passage 31.Pilot control oil line 44.Pressure switch
7. Travel motor A port 19.Balanced valve 32.Pilot control oil line 45.Pilot valve group
piping-lh 20.Oil return passage 33.Solenoid valve 46.Right travel spool
8. Travel motor B port 21.Check valve 34.Left travel spool 47.Control passage
piping-lh 22.Transmission reversing 35.Pressure passage 48.Control passage
9. Control passage valve 36.
10.Motor B port passage 23.Control passage
11.Pilot control oil line 24.Variable displacement
12.Pilot control oil line cylinder

When the travel fast-slow gear control switch is in the "Rabbit" state and the travel pilot valve (13) is
operated toward forward, the pilot pressure reaches the port 1 and port 3 of the travel pilot valve (13)
after passing through the pilot valve group (45) and the solenoid valve (33) from the pilot pump (41), and
reaches the control ports of the travel -lh spool (35) and the travel -rh spool (46) after passing through
the pilot lines (31) and (11) respectively; at the same time, the control oil in the control chamber-lh of the
travel -lh spool (35) and the travel -rh spool (46) flows back to tank (40) after passing through the piping
(32) and (12), oil port 2 and 4 of the travel pilot valve (13) and the pilot return line (38); with the action of
the respective pilot control pressure, the travel -lh spool (35) and the travel -rh spool (46) reverse to
corresponding position respectively, at this moment, the travel fast-slow gear control switch is in the
"Rabbit" state of the fast gear, namely, energizing the solenoid valve (37) of the four-step solenoid valve
group (39) to make it reverse; the pilot control pressure reaches the transmission reverse valve (28) and
(22) of the travel motor-lh and the reducer (1) as well as the travel motor-rh and reducer (2) after passing
through the piping, center swing joint (30) and the travel fast-slow gear control line (14) to push the
reverse valve to reverse; at this moment, the oil inlet pressure of the motor-rh enters the variable cylinder
(24) of the travel motor-rh after passing through the check valve (21), transmission reverse valve (22)
and the control passage (23), while the oil inlet pressure of the motor-lh enters the variable cylinder (29)
of the travel motor-lh after passing through the check valve (27) and the transmission reverse valve (28),
thus, with the action of the oil inlet pressure, the left and right motors are in the position with the least
discharge capacity, which is called "fast gear" state;
3-146
3.3 Hydraulic System December 30, 2017
3.3.3 Hydraulic Principle CLG930E/936E

The pressure oil output from the left pump (42) of the main pump reaches the port A of the left travel
motor & reduction gear (1) after passing through the pressure passage (36), left travel spool (35), center
swivel joint (30) and the port B piping (8) of left travel motor; the pressure oil enters the motor by passing
through the motor port B passage (10); at the same time, the pressure oil pushes the balanced valve (6)
to reverse by passing through the control passage (9), and the pressure oil enters the motor brake (3) to
unlock after passing through the balanced valve (6) and the control passage (4); the return oil of the
motor connects with the hydraulic oil tank (40) after passing through the return passage (5) and balanced
valve (6) to port A , and then passing through the port A piping (7) of left travel motor, the center swivel
joint (30) and the left travel spool (35); at the same time, the pressure oil of the right pump (43) reaches
the port A of the right travel motor & reduction gear (2) after passing through the check valve (45), right
travel spool (46), center swivel joint (30) and the port B piping (16) of right travel motor; the pressure
enters the motor by passing through the motor port A passage (17); at the same time, the pressure oil
pushes the balanced valve (19) to reverse by passing through the control passage (18), and the
pressure oil enters the motor brake (25) to unlock after passing through the balanced valve (19) and the
control passage (26); the return oil of the motor reaches the port B of the balanced valve (19) after
passing through the return passage (20) and the balanced valve (19), and then connects with the
hydraulic oil tank (40) after passing through the port B piping (15) of right travel motor, center swivel joint
(30) and the right travel spool (46); thus, with the action of the pressure oil, the left and right motors and
the reduction gear drive the machine to move backward slowly.
As the reversing of the right travel spool (46), the return passage outputting the control pressure from the
pilot valve group (45) port B is stopped and the pressure is produced, this pressure acts on the pressure
switch (44) after passing through the control passage (47) and (48), and then the pressure switch (44)
transmits the electrical signal to realize the function of travel warning.
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.3 Hydraulic Principle

BLANK PAGE
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3.3 Hydraulic System December 30, 2017
3.3.3 Hydraulic Principle CLG930E/936E

3.3.3.16 Travel Backward Working Circuit (Slow)

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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.3 Hydraulic Principle

1. Left travel motor & 13.Travel pilot valve 25.Motor brake 37.Solenoid valve
reduction gear 14.Travel fast and slow gear 26.Control passage 38.Pilot return lines
2. Right travel motor & control line 27.Check valve 39.Four-step solenoid valve
reduction gear 15.B port pipeline, right 28.Transmission reversing group
3. Motor brake travel motor valve 40.Hydraulic oil tank
4. Unlock pressure oil 16.A port pipeline, right 29.Variable displacement 41.Pilot pump
passage travel motor cylinder 42.Left pump
5. Motor A port oil passage 17.Motor A port oil passage 30.Center revolving joint 43.Right pump
6. Balanced valve 18.Control passage 31.Pilot control oil line 44.Pressure switch
7. Travel motor A port 19.Balanced valve 32.Pilot control oil line 45.Pilot valve group
piping-lh 20.Oil return passage 33.Solenoid valve 46.Right travel spool
8. Travel motor B port 21.Check valve 34.Left travel spool 47.Control passage
piping-lh 22.Transmission reversing 35.Pressure passage 48.Control passage
9. Control passage valve 36.
10.Motor B port passage 23.Control passage
11.Pilot control oil line 24.Variable displacement
12.Pilot control oil line cylinder

When the travel fast-slow gear control switch is in the slow gear - "Tortoise" state and the travel pilot
valve (13) is operated toward backward, the pilot pressure reaches the port 2 and port 4 of the travel pilot
valve (13) after passing through the pilot valve group (45) and the solenoid valve (33) from the pilot
pump (41), and reaches the control ports of the left travel spool (35) and the left travel spool (46) after
passing through the pilot lines (32) and (12) respectively; at the same time, the control oil in the control
chamber-lh of the left travel spool (35) and the right travel spool (46) flows back to tank (40) after passing
through the piping (31) and (11), oil port 1 and 3 of the travel pilot valve (13) and the pilot return line (38);
with the action of the respective pilot control pressure, the left travel spool (35) and the right travel spool
(46) reverse to corresponding position respectively, and at this moment, the travel fast-slow gear control
switch is in the "Tortoise" state of the slow gear, namely, power off the solenoid valve (37) of the four-step
solenoid valve group (39) to make it reset (as shown in the figure); the control pressure (14) is back to
the tank after passing through the solenoid valve (37) of the pilot valve group (39); the transmission
reverse valve (28) and (22) reset with the action of the spring, and the control pressure in the variable
cylinder (29) and (24) of the left and right travel motor connect with the drainage port and are back to the
tank after passing through the transmission reverse valve (28) and (22) respectively, thus, with the action
of the spring force, the variable cylinders of the left and right motors make the motor in the position with
the maximum discharge capacity, namely, the "slow gear" state;
3-150
3.3 Hydraulic System December 30, 2017
3.3.3 Hydraulic Principle CLG930E/936E

The pressure oil output from the left pump (42) of the main pump reaches the port A of the left travel
motor & reduction gear (1) after passing through the pressure passage (36), travel -lh spool (35), center
swivel joint (30) and the Port A piping (7) of left travel motor; the pressure oil enters the motor by passing
through the motor A port passage (5); at the same time, the pressure oil pushes the balanced valve (6)
to reverse by passing through the control passage (9), and the pressure oil enters the motor brake (3) to
unlock after passing through the balanced valve (6) and the control passage (4); the return oil of the
motor connects with the hydraulic oil tank (40) after passing through the return passage (10) and
balanced valve (6) to the B port, and then passing through the travel motor B port piping-lh (8), the
center swivel joint (30) and the travel -lh spool (35); at the same time, the pressure oil of the right pump
(43) reaches the B port of the travel motor-rh & reduction gear (2) after passing through the check valve
(45), travel -rh spool (46), center swivel joint (30) and the travel motor B port piping-rh (15); the pressure
enters the motor by passing through the motor B port passage (20); at the same time, the pressure oil
pushes the balanced valve (19) to reverse by passing through the control passage (18), and the
pressure oil enters the motor brake (25) to unlock after passing through the balanced valve (19) and the
control passage (26); the return oil of the motor reaches the A port of the balanced valve (19) after
passing through the return passage (17) and the balanced valve (19), and then connects with the
hydraulic oil tank (40) after passing through the travel motor A port piping-rh (16), center swivel joint (30)
and the travel -rh spool (46); thus, with the action of the pressure oil, the left and right motors and the
reduction gear drive the machine to move backward slowly.
As the reversing of the right travel spool (46), the return passage outputting the control pressure from the
pilot valve group (39) port B is stopped and the pressure is produced, this pressure acts on the pressure
switch (44) after passing through the control passage (47) and (48), and then the pressure switch (44)
transmits the electrical signal to realize the function of travel warning.
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CLG930E/936E 3.3.3 Hydraulic Principle

BLANK PAGE
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3.3 Hydraulic System December 30, 2017
3.3.3 Hydraulic Principle CLG930E/936E

3.3.3.17 Bilateral Travel and Boom Rising Compound Operating Circuit

1. Left travel motor & 7. Pilot control oil line 12.Pilot control oil line 17.Left pump
reduction gear 8. Pilot control oil line 13.Orifice 18.Right pump
2. Travel pilot valve 9. Straight travel valve 14.Pilot control oil line 19.Pilot pump
3. Right hand pilot valve 10.Orifice 15.Pilot control oil line 20.Right travel spool
4. Solenoid valve 11.Pilot control oil line 16.Pilot valve group 21.Right travel motor &
5. Boom spool 1 reduction gear
6. Left travel spool
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December 30, 2017 3.3 Hydraulic System
CLG930E/936E 3.3.3 Hydraulic Principle

Under normal travel state (namely without other actions), the left pump (17) supplies oil to the left travel
spool (6) and the right pump (18) supplies the oil to the right travel spool (20). With the both sides
traveling, when any actions of the swing or working implement are operated synchronously, the control
pressure (11) of the straight travel valve (9) is produced because of the stopping function of the spool
reversing of the travel spool and the boom or the work implement, which pushes the straight travel valve
(9) to reverse, at this moment, the output oils of the left and right pumps are distributed again by passing
through the straight travel valve (9); the pressure oil output from the right pump (18) is supplied to the left
and right travel valve, and the pressure oil output from the left pump (17) is supplied to the work
implement preferentially, then, the redundant oil is supplied to travel, thus, it is equal to that the left and
right travel is supplied by one oil source, which keeps them traveling straightly.
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3.4 Work Implement December 30, 2017
3.4.1 Maintenance References of Main Parts CLG930E/936E

3.4 Work Implement

3.4.1 Maintenance References of Main Parts

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December 30, 2017 3.4 Work Implement
CLG930E/936E 3.4.1 Maintenance References of Main Parts
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3.4 Work Implement December 30, 2017
3.4.1 Maintenance References of Main Parts CLG930E/936E

Judgment standards
No. Item Standar Tolerance Standard Permissible Measures
d size Shaft Hole clearance clearance

Clearance between mounting

-0.036 +0.209
1 pin and bushing of swing φ110 0.120~0.280 0.120~1.0
-0.071 +0.084
platform and boom

Clearance between mounting

-0.036 +0.209
2 pin shaft and bushing of φ110 0.120~0.280 0.120~1.0
-0.071 +0.084
boom and arm
Clearance -0.036 +0.175
CLG930E φ90 0.131~0.246 0.131~1.0
between -0.071 +0.095
mounting pin
3
shaft and -0.036 +0.166
bushing of arm CLG936E φ100 0.118~0.237 0.118~1.0
-0.071 +0.082
and bucket
Clearance between mounting Replacement
-0.036 +0.170
4 pin shaft and bushing of arm φ90 0.106~0.241 0.106~1.0
-0.071 +0.070
and rocker lever
Clearance -0.036 +0.170
CLG930E φ90 0.106~0.241 0.106~1.0
between -0.071 +0.070
mounting pin
5 shaft and
bushing of link -0.036 +0.253
CLG936E φ100 0.156~0.324 0.156~1.0
and rocker -0.071 +0.121
lever
Clearance -0.036 +0.175
CLG930E φ90 0.131~0.246 0.131~1.0
between -0.071 +0.095
mounting pin
6
shaft and -0.036 +0.166
bushing of link CLG936E φ100 0.118~0.237 0.118~1.0
-0.071 +0.082
and bucket
 3-157
December 30, 2017 3.4 Work Implement
CLG930E/936E 3.4.2 Maintenance References of Arm Part

3.4.2 Maintenance References of Arm Part

3-158
3.4 Work Implement December 30, 2017
3.4.2 Maintenance References of Arm Part CLG930E/936E

CLG930E CLG936E
Measuremen CLG930E CLG936E
No. Tolerance
t position
Standard size Shaft Hole Shaft Hole
-0.036 +0.054 -0.036 +0.054
1 — φ100 φ110
-0.071 0 -0.071 0
+1 +1
Arm side 127 137
0 0
2
0 0
Cylinder side 125 135
-0.5 -0.5
-0.036 +0.054 -0.036 +0.054
3 — φ110 φ110
-0.071 0 -0.071 0
+0.5 +0.5
Boom side 370 417
0 0
4
0 0
Arm side 366 413
-1 -0.5
5 — 216.8 260 ±0.5 ±0.5
6 — 552.1 554 ±1 ±1
7 — 981.3 985 ±1 ±1
8 — 3042.3 3190 ±2 ±3
9 — 2803.8 2994.2 ±1 ±1.5
10 — 450 575 ±0.5 ±1
11 — 680 700 ±0.5 ±0.5
12 — 680 695 ±0.5 ±0.5
13 — 450 585 ±0.5 ±0.5
14 — 1601 1692 — —
-0.036 +0.224 -0.036 +0.159
15 — φ90 φ100
-0.071 +0.17 -0.071 +0.072
0 0
Link itself 358 396
-0.5 -0.5
16 When pressing
0 0
and installing 380 418
-0.7 -0.7
the bushing
-0.036 +0.224 -0.036 +0.159
17 — φ90 φ100
-0.071 +0.17 -0.071 +0.072
0 0
Arm itself 358 396
-0.5 -0.5
18 When pressing
0 0
and installing 380 418
-0.7 -0.7
the bushing
Minimum 1799 1850 ±2 ±4
19
Maximum 2934 3070 ±4 ±7
 3-159
December 30, 2017 3.4 Work Implement
CLG930E/936E 3.4.3 Maintenance References of Bucket Part

3.4.3 Maintenance References of Bucket Part

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3.4 Work Implement December 30, 2017
3.4.3 Maintenance References of Bucket Part CLG930E/936E

Standard size Tolerance

No.
CLG930E CLG936E CLG930E CLG936E
1 446.4 562.6 ±0.5
2 56.6 160.3 ±0.5
3 97.2° 105.9° —
4 450 585 ±0.5
5 1601 1692 —
6 122.3 159 —
7 144.8 184 —
8 125.4 177.8 —
9 R120 R130 —
10 R110 R130 —
11 R400 R800 —
+0.5
12 380.5 418.5
0
13 58.5 83 —
14 108.5 113 —
15 522.5 589.5 —
+0.054 +0.159
16 φ90 φ100
0 +0.072
17 φ93 φ104 —
18 — 160 —
19 φ190 φ186 —
20 φ22 φ22 —
 3-161
December 30, 2017 3.5 A/C System
CLG930E/936E 3.5.1 Layout Diagram of A/C Pipeline

3.5 A/C System

3.5.1 Layout Diagram of A/C Pipeline

4
5

2
1

1. A/C air duct 6. A/C condenser

2. Evaporator assembly (HVAC) 7. Refrigerant pipeline
3. Thermal return pipeline A: Fresh air intake
4. Thermal inlet pipeline B: Internal circulation air
5. A/C Compressor C: Cold and hot air
3-162
3.6 Electrical System December 30, 2017
3.6.1 Engine Control CLG930E/936E

3.6 Electrical System

3.6.1 Engine Control

Engine

Electric lock start signal

Pilot shutoff valve signal

Starting signal of main controller

Starter relay

Throttle actuator

Power-on signal
of electric lock Main controller

Battery relay
Engine oil pressure signal
Electric lock start signal
Accelerator knob signal

Engine speed signal

Battery

1. Start the engine (Note: The starting signal of the starter relay is
controlled by the ECM, and the starter relay is
When the electric lock is turned to the "Start"
driven jointly by the main controller control
position, the electric lock starting signal is
starting signal and the pilot handle control signal.
detected by the main controller, and then the
When the machine is free of failure, and the
main controller sends main controller control
excavator is started following the correct steps,
starting signal to transmit the power supply
the starting process of the engine is described as
signal to the power end of the start motor, then
above.)
the engine is started.
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December 30, 2017 3.6 Electrical System
CLG930E/936E 3.6.2 Display System

At the same time, the main controller detects the 1. Alarm information when the complete
accelerator knob signal, and sets the machine fails;
corresponding engine speed of the accelerator
2. Working condition information of the machine
knob as the set speed, then sends the speed
(including the engine speed, hydraulic oil
control signal to the engine controller via the
temperature, etc.).
CAN bus, so as to control the oil feed pump and
make the current speed become the set speed 3. Maintenance information of the machine.
steadily.
The keys for special purposes (part of the keys
2. Engine speed control are equipped with LED indicator) on the control
panel of the display are used to operate the
Each gear of the accelerator knob corresponds
control system of the machine.
to an engine speed, and the engine controller
controls the oil injection quantity according to the
speed control signal sent by the main controller,
so as to control the engine speed.
3. Stop the engine
When the electric lock is turned to the "OFF"
position, the engine stops.

3.6.2 Display System

Engine controller

(Alarm signal and

engine state
CAN bus information)

(Alarm signal and

hydraulic system Command signal
information)

Main controller Display

The operator can obtain the operating condition

of complete machine through the display system.
The display shares the data with the engine
controller and the main controller via CAN bus,
and the information of the machine is displayed
on the LCD screen.
The contents displayed on screen can be divided
into the following parts.
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3.6 Electrical System December 30, 2017
3.6.2 Display System CLG930E/936E

3.6.2.1 Display

LCD

Button panel
 3-165
December 30, 2017 3.6 Electrical System
CLG930E/936E 3.6.2 Display System

Pin Input and

Signal
num output port Description
Name
ber Function
The pin is not
11 NC -
adopted
The pin is not
12 NC -
adopted
The pin is not
13 NC -
adopted
The pin is not
14 NC -
adopted
The pin is not
15 NC -
adopted
The pin is not
16 NC -
adopted
The pin is not
Performance 17 NC -
adopted
1. With LCD screen, the backlight brightness is The pin is not
18 NC -
adjustable. adopted

2. Internal integrated microprocessor and The pin is not

19 NC -
adopted
storage unit.
The pin is not
3. A build-in buzzer is installed, the volume is 20 NC -
adopted
adjustable and the mute is available. The pin is not
21 NC -
4. Build-in button battery adopted
The pin is not
Pin Input and 22 NC -
Signal adopted
num output port Description The pin is not
Name 23 NC -
ber Function adopted
1 CAN Low CAN Low The pin is not
24 NC -
adopted
2 CAN Shield CAN Shield
The pin is not
The pin is not 25 NC -
3 NCa - adopted
adopted
Input 24V when
The pin is not Electric lock the start switch
4 NC - 26 Number input
adopted ON is turned to "on"
5 Earth Grounding position
24V, always a. NC indicates that the stitch is not adopted.
Battery Battery
6 connect with
power supply voltage
the battery
24V, always
Battery Battery
7 connect with
power supply voltage
the battery
8 CAN High CAN High
The pin is not
9 NC -
adopted
10 Earth Grounding
3-166
3.6 Electrical System December 30, 2017
3.6.2 Display System CLG930E/936E

3.6.2.2 LCD Part of Display

 3-167
December 30, 2017 3.6 Electrical System
CLG930E/936E 3.6.2 Display System

Icon
Icon Content Description
color

Working mode The work mode is “P”,“E”,“F”,“L”,“B”and“ATT”.

Blue The accelerator has 12 gears changing from "1" to "12", and
Normal display

Accelerator
when the accelerator knob is failed, the icon in this place is
gear
nothing

Time Display the real time of that very day

Black
Operating
Engine total operation time
hour

Display when the travel speed is fast: , display when the

Travel speed

travel speed is slow:

Idling function When the idling function is enabled, the icon will be displayed

1) When the automatic power boosting function is valid, the

icon is always displayed on the main interface no matter
Function state display

whether the engine is operating.

Transient 2) Manual power boosting, when the manual transient power
power Black boosting knob is pressed, the icon will be displayed; when the
boosting manual power boosting knob is released, the icon will
function disappear.
3) Under the L mode, the icon will be displayed all the time
unless the vehicle is in the travel state, and the automatic
power boosting cannot be canceled under the L mode.
Preheating When the preheating function is used, the icon will be
function displayed, otherwise it will not be displayed
Flattening When the flattening function is enabled, the icon will be
function displayed, otherwise, it will not be displayed
Trenching When the trenching function is enabled, the icon will be
function displayed, otherwise, it will not be displayed.
3-168
3.6 Electrical System December 30, 2017
3.6.2 Display System CLG930E/936E

Icon
Icon Content Description
color
Battery is not It will warn when the battery is not charged, and at this
charged moment, check the charging circuit and eliminate the failure

Fuel contains
It will warn when the fuel contains water
water

Engine oil
High alarm of engine oil pressure
pressure
Warning information display

Coolant level It will warn when the coolant level is low

Engine oil
It will warn when the engine oil level is low
level
Red
Air filter alarm Blockage alarm of air filter

Hydraulic oil It will warn when the hydraulic oil temperature exceeds the
temperature limit
It will warn when the hydraulic oil level is low, and this function
Hydraulic oil
requires that the hydraulic oil level switch is equipped on the
level
machine
Over lifting It will warn when the lifting load is higher than the system
load specified value
Maintenance The icon will be displayed when there are some maintenance
service items not finished by the user
When the machine is failed, the failure will be displayed in the
Warning
form of text or the LiuGong DTCs.
information
In case of the warning caused by the system failures, the red
display
alarm bell icon will flicker all the time.
 3-169
December 30, 2017 3.6 Electrical System
CLG930E/936E 3.6.2 Display System

Icon
Icon Content Description
color
Scope % Color Description
When the icon is filled with red color
accompanied by the warning information
≤10 Red
of "Low fuel level", indicate that the fuel
level is too low
Fuel Level
When the icon is filled with yellow color,
10~20 Yellow it indicates that the fuel level is slightly
low
When the icon is displayed normally, it
Virtual gage

20~100 Green
indicates that the fuel level is normal
Range °C Color Description
Normal
≤30 Blue
temperature
Normal
30~100 Green
Coolant temperature
temperature 100~102 Yellow High temperature
Overhigh
102~105 Red
temperature
Extremely high
?105 Red
temperature
3-170
3.6 Electrical System December 30, 2017
3.6.2 Display System CLG930E/936E

3.6.2.3 Display Key Panel For the machine equipped with the attachment,
the B/ATT mode is invisible in the selecting menu
unless the B/ATT is enabled.
When the B mode or the ATT mode is selected,
the system will pop up the following information
prompt box:

Confirm to enter broken mode?

Yes No

Confirm to enter hydraulic cutter mode?

There are 6 buttons for special purposes on the Yes No

panel, and the LED indicators are equipped for
part of the buttons.

1. Working mode selecting key has no

2. A LED indicator is equipped for the
LED indicator
trenching function key at the top left corner
Press the key to make the mode selection menu Press the key to trigger the trenching mode
pop up, and then the user can select the
When the trenching function is enabled, the
expected working mode. corresponding icon on the main interface and the
LED indicators (beside the key) on the panel will
be illuminated.
High-speed mode
The trenching function and the flattening function
are not mutually exclusive - namely the both
Economic mode
functions can be enabled at the same time.
Fine mode
Lifting mode 3. A LED indicator is equipped for the
flattening function key at the top left corner,
Broken mode
and press the key to trigger the flattening
Hydraulic cutter mode
function. When the flattening function is
enabled, the corresponding icon on the main
interface and the LED indicators (beside the
key) on the panel will be illuminated.
When the working mode selecting menu pops The trenching function and the flattening function
up, press the working mode key again to close are not mutually exclusive - namely the both
the menu. functions can be enabled at the same time.
About the B and ATT mode
 3-171
December 30, 2017 3.6 Electrical System
CLG930E/936E 3.6.2 Display System

4. LED indicator is equipped on both sides b. User presses the mute key - the travel
of the travel speed control key (rabbit/ buzzer is turned off and the LED indicator
tortoise) goes off
Press the key to switch between the low speed c. Vehicle stops running - travel buzzer mute
state and high speed state, and the requests to turn off, namely, invalid
corresponding icon (rabbit/tortoise) on the main d. Vehicle runs again - travel buzzer sounds,
interface and the two corresponding LED and the LED indicator is illuminated again
indicators (beside the key) will switch (namely, the previous mute operation is
synchronously. invalid)
The travel icon on the display and the LED Moreover, there are eleven common/navigation
indicator is only consistent with the state keys on the panel:
selected by the user, not the state of the travel
solenoid valve. Similarly, the selected state 1. The 4 keys are F1, F2, F3 and F4
(indicating icon or light) is not affected by respectively, which are defined as the display
whether the vehicle is in the running state or soft keys
whether the travel solenoid valve is failed. 2. Four navigation keys (up/down/left/right)
3. Selection key is marked as "O" - the function
5. A LED indicator is equipped for the of which is similar to the clicking or selecting
automatic idle speed control key at the top function of the mouse left button
right corner 4. Confirm key (green), mark "√" signal - for OK,
Press the key to trigger the automatic idle speed entrance or confirm function
function. The corresponding icon on the main 5. Cancel key (red) is marked as "×" - used to
interface and LED indicator (beside the key) will cancel, exit or negate
be illuminated synchronously.

6. A LED indicator is equipped for the travel

buzzer mute key (outlaid horn) at the top right
corner
When the vehicle starts to drive, the buzzer
sounds, and press the travel buzzer mute button
once, the buzzer stops; press the travel buzzer
mute button again, the buzzer recovers to sound.
When the travel buzzer sounds, the LED
indicator beside the button will be illuminated
synchronously.
When the vehicle is stationary, the buzzer cannot
be enabled or turned off by pressing the travel
buzzer mute button.
Note: The main sequence is as follows:
a. Vehicle starts to run- the travel buzzer
sounds and the LED indicator is
illuminated
3-172
3.6 Electrical System December 30, 2017
3.6.2 Display System CLG930E/936E

3.6.2.4 Software Introduction

Soft key Name Function introduction

The soft key can be displayed only when the internal buzzer sounds and is
Internal buzzer mute
able to become mute

Current fault Press the key and the system will enter the current failure interface.

Set Press the key and the system will enter the setting interface.

Display setting Press the key and the system will enter the display setting interface.

Press the key and the system will enter the maintenance interface, which
Maintenance mainly displays the information of the item requiring maintenance. The key
will be displayed all the time even if there is no maintenance item.

Maintenance help Press the key and the system will enter the maintenance help interface.

Press the key and the system will enter the main interface. Press the X key
Main interface (with no small windows popped up) to return to the main interface no
matter what interface is displayed.
Press the key and the system will enter the service mode menu interface.
Note: The key shares a same position with the internal buzzer mute key,
Service mode menu and it will be hidden when the internal buzzer mute key icon is displayed.
This key and the corresponding functions can be visible only when the
mute key is pressed to make the buzzer silent.

Machine state Press the key and the system will enter the machine state interface.

Specific machine state Press the key and the system will enter the specific machine state
interface interface.

Press the key and the system will make the parameter configuration
Parameter window pop up under the machine state interface. Invoking this key will
configuration mode make the display enter a specific working mode, under which the user can
select the parameters expected to monitor in the popped up window list.

Historical failure Press the key and the system will enter the historical failure interface.

Press the key and the system will enter the maintenance history interface.
Maintenance history If there is no maintenance history record at present, the soft key function
will be off (icon is gray).
Press this key and the system will enter the maintenance operation
New maintenance
interface. Under this interface, the user can perform the maintenance
record
operation and record.
This key and its function can be visible only in the maintenance operation
interface, and can be used only when one or more maintenance items are
Save maintenance
selected. Press this key and a new maintenance record will be created,
record
and the interface will be switched to the "Save this record" interface under
the maintenance history interface synchronously.
 3-173
December 30, 2017 3.6 Electrical System
CLG930E/936E 3.6.2 Display System

Soft key Name Function introduction

This key and its function can be visible only in the maintenance operation
interface. Press this key and the system will cancel the saving of this
maintenance record operation (namely cancel the selected maintenance
Cancel maintenance
item) and return to the maintenance interface. Note: In the maintenance
record
operation interface, if any maintenance item is selected, the display will
ignore the X key operation (normally, pressing the X key will return to the
main interface) at this moment.
3.6.2.5 User Mode Under the B mode, move the cursor to this
option, and press the 0-type key to activate the
1. Set functions of this option. Then, the user can adjust
the level from 1 to 4 between the L level and H
Press the "Set" key and the system will enter the level using the left/right navigation keys.
setting interface. Some corresponding menu After that, press the "√" key to confirm. Press the
options for the user to perform some basic "X" key to cancel the current setting.
settings are provided in this setting interface.
2. Attachment flow adjustment
● Breaking hammer flow adjustment
It can be set only when the working mode is in
● Attachment flow adjustment ATT mode, and the operation instruction is
● Date/time set similar to that of the breaking hammer.

● Language setting Under the ATT mode, move the cursor to this
option, and press the 0-type key to activate the
● Lifting overload monitoring functions of this option. Then, the user can adjust
● Automatic transient power boosting the level from 1 to 4 between the L level and H
level using the left/right navigation keys.
Breaking hammer flow adjustment After that, press the "√" key to confirm. Press the
Attachment flow adjustment
"X" key to cancel the current setting.

Set date/time
3. Date/time set
Language settings

Lifting overload monitoring

Automatic transient power boosting

1. Breaking hammer flow adjustment

It can be set only when the working mode is B
mode, namely, the flow can be set and adjusted
by the user. This adjustment is invalid in other
working modes, namely, this option is gray and
cannot be selected.
3-174
3.6 Electrical System December 30, 2017
3.6.2 Display System CLG930E/936E

When this option is selected, the following date/ Select the required language using the
time setting dialog box will pop up. The time is navigation keys (up/down) and press the "0" -
displayed in 24-hour. Press the navigation key to type key or "√" to confirm. Press the "×" key to
select the year, month, day, hour, minute and cancel the current setting.
second respectively, and then press the 0 type
confirmation key to make the virtual numeric
keyboard pop up and enter the number to be set. Breaking hammer flow adjustment

Attachment flow adjustment

Set date/time Set date/time

Language

Automatic transient power boosting

Set date/time

5. Lifting overload monitoring

This option can be selected only when the
working mode is L. As long as in the L mode, the
Press the confirmation key "√" or the cancel key
over lifting load monitoring function will be
"×" (with the virtual numeric keyboard not
enabled, namely, the block in the front of this
displayed), and the system will turn off the date/
option will be selected. User can close this
time setting dialog box and return to the setting
function, and meanwhile the mark in the block
interface. Pay attention to that if the cancel key
will disappear.
"×" is pressed, all the setting will be canceled.
6. Automatic transient power boosting
4. Language setting
During each power on, the mark of the block in
Different languages can be selected (Chinese,
the front of this option is nothing.
English, etc.) by different customers.
Under the L mode, this option is gray and not
optional, and the block is marked as selected.
When the vehicle is running, this option is gray
(not optional) and the block mark is empty.
 3-175
December 30, 2017 3.6 Electrical System
CLG930E/936E 3.6.2 Display System

2. Display setting 4. Keytone

Turn on/off the keytone with this option.
Display setting interface includes the menu
options with which the different characteristics of
3. Maintenance
the display can be adjusted by the user.
● Contrast This interface mainly displays the items which
are about to expire or have expired but not
● Brightness setting
maintained. This interface has two lists of
● Buzzer volume contents.
● Keytone ● Maintenance items
● Interval

Maintenance item Interval

Replace engine oil
Replace engine oil filter element
Replace fuel filter element
Keypad tone

1. Contrast
Generally, the contrast of the LCD screen is 1. Maintenance items
implemented according to the factory setting.
This list mainly displays the item names which
However, the user can adjust the contrast by
moving the cursor bar. are about to expire or have expired but not
maintained. Refer to the following list for the
2. Brightness setting maintenance item and the interval.
User can move the cursor bar to set the LCD Maintenance item Interval
backlight brightness. There are two independent
settings, which are the day mode and night Replace engine oil 250h
mode. Replace engine oil filter element 250h

When the vehicle work light is on, the system will Replace fuel filter element 250h
enter the night mode, and meanwhile, the icon Fill the lubricant for the swing bearing 500h
will changed as the "Moon": . Check the fuel oil filter 500h
3. Buzzer volume Clean the exterior of the radiator 500h
Replacing the return oil filter element of
User can move the cursor bar to set the buzzer hydraulic
500h
volume in the display.
Replace the air filter element 500h
Note: In case of the failure of the system, the Replace the pump filter element 1000h
buzzer will warn in the highest volume regardless
Replace the swing reduction gear oil 1000h
of the volume set by the user.
Replace the pilot engine oil filter 1000h
3-176
3.6 Electrical System December 30, 2017
3.6.2 Display System CLG930E/936E

Maintenance item Interval

Replace the hydraulic oil 2000h
Current fault:
Rinse the inlet filter element 1500h Mechanical type
Change coolant and clean the inner of Blockage of air filter
2000h
radiator
Replace the gear oil of travel reduction
1000h
gear

The maintenance items and intervals are

subject to the regular maintenance section in
"Operation and Maintenance Manual".
2. Interval
This list displays the count down (engine working When a failure information is selected, press the
hours) of the item which is going to be confirmation key and then a information bar of
maintained, or the expired time for the item not the warning information will pop up. In this
maintained. For the former (it is not time to information bar, different icons and colors
maintain), the time number is black; if the interval indicate the different warning levels. Namely,
is less than or equal to 10 hours, the time yellow color indicates the general warning level
background will be highlighted and is yellow. while the red color indicates the serious warning
level.
For the latter (beyond the service period),add "-"
before hour and display white fond and red Moreover, this information bar also includes the
background. date when the warning is triggered and the
engine working hours.
3. Current fault
All the failures are classified as 3 types, which Current fault:
are electrical failure, mechanical failure and ECM Mechanical type
(engine). The corresponding failure is displayed Blockage of air filter

under the related failure classification. Each

failure information is defined by the LiuGong
DTC with 6 digits or the Cummins DTC (4 digits),
and is displayed together with its failure
information (at the current failure interface). The
failure information displayed is red. Blockage of air filter
 3-177
December 30, 2017 3.6 Electrical System
CLG930E/936E 3.6.3 Electrical Control System

3.6.3 Electrical Control System

Engine
Throttle actuator

Display
Accelerator knob

Main controller Electric Lock

CAN bus

Fuel sensor

Temperature sensor

Hydraulic system

3.6.3.1 Work Mode

Select the corresponding work mode by the display, and then the controller implements the
corresponding functions of the selected mode. The work mode is classified into 6 kinds as follows.
● P --- Heavy load mode, it is applicable for the heavy load condition to take efficiency as priority.
● E --- Economic mode, it is applicable for the general operation to take the oil consumption as priority.
● F --- Fine mode, it is applicable for the operation with fine actions.
● L --- Lifting mode, it is applicable for the operation to lift the materials.
● B --- Breaking hammer mode, it is applicable for the operation to use breaking hammer.
● ATT --- Attachment mode, it is applicable for the operation of the attachment such as the hydraulic
crusher and grapple.
3-178
3.6 Electrical System December 30, 2017
3.6.3 Electrical Control System CLG930E/936E

3.6.3.2 Automatic Idling Function

Engine
Throttle actuator

Display
Accelerator knob signal

Main controller
CAN bus Handle pilot pressure
switch signal

Foot pilot pressure

switch signal

Attachment pressure
switch signal

Function: When the engine is in idling speed, operate the

handle, foot step or the control lever of the
When you are not operating the lever, pedal or attachment, then the hydraulic request signal is
attachment control lever, the engine speed will available, and the engine will resume to the
drop to the preset idle speed so as to achieve the speed which the accelerator knob indicates.
purpose of reducing fuel consumption or noise.
Note: The hydraulic request signal includes the
No matter the lever or pedal, either or the control handle pilot pressure switch signal, foot step pilot
lever of attachment is operated, the engine pressure switch signal and the attachment
speed will restore to the corresponding speed of secondary pressure switch signal.
the current accelerator knob.

Operation: Engine speed Level-1 deceleration

Level-2 deceleration
1. When the handle, foot step and the control
lever of the attachment are not handled Current speed
(without hydraulic request signal)
Current speed -100RPM
If the hydraulic request signal is unavailable
within 1s, the engine speed will reduce about
100RPM based on the current speed. If the Idle speed
hydraulic request signal is still unavailable after 3
seconds, the engine speed will decrease to the
Without hydraulic With hydraulic
idling speed (about 1000RPM). request signal request signal
Time (s)

2. When the handle, foot step or the control

lever of the attachment are operated (with
hydraulic request signal).
 3-179
December 30, 2017 3.6 Electrical System
CLG930E/936E 3.6.3 Electrical Control System

3.6.3.3 Transient Power Boosting Function

Display

(Automatic power boosting command)

CAN bus

Control signal of transient

Signal of transient power boosting solenoid
power boosting button valve
Main controller
Transient power
boosting solenoid valve
P1 pump-lh pressure signal

P2 pump-lh pressure signal

pedal pilot pressure
Switch signal of

Function: 2. Automatic power boosting

Under the P, E and F mode, it will increase the The automatic power boosting function can be
digging force of the excavator within certain time. selected from the display menu. When the P1
Under the L mode, it will increase the digging pump pressure signal is detected by the main
force of the excavator continuously. Under the B controller or the P1 pump pressure signal is
and ATT mode, this function is unavailable. greater than or equal to 34MPa and maintains for
When the vehicle is running, the transient power over 3 seconds, the main controller will output
boosting function will be unavailable. the power boosting solenoid valve control signal
to increase the digging force.
The transient power boosting function is divided
into manual power boosting and automatic When the conditions of the automatic power
power boosting. boosting function are met, the machine will
increase the digging force for 8s, then the button
1. Manual power boosting will reset automatically. 10s later, whether the
The operator presses the transient power power boosting function being enabled depends
boosting button to increase the digging force for on if the conditions of the transient power
8s, then the button will reset automatically. 10s boosting are met or not.
later, whether the power boosting function being
enabled depends on if the transient power
boosting button is pressed or not.
3-180
3.6 Electrical System December 30, 2017
3.6.3 Electrical Control System CLG930E/936E

3.6.3.4 Overheating Protection Function

Throttle actuator Engine

Display

CAN bus Coolant temperature

sensor
Main controller
Hydraulic oil
temperature sensor

Main pump

Function:

When the coolant or the hydraulic oil temperature is high, in order to protect the engine and the hydraulic
element from overheating, the pump current and the engine speed will be reduced to protect the engine
and the hydraulic element.
The overheating protection function is divided into level 1, level 2 and level 3.

Protection
Working conditions Measures Reset conditions
level
Work mode: P
Hydraulic oil temperature: less
Hydraulic oil temperature Engine speed: keep as original
Level 1 than 82°C
above 86°C or the coolant Pump current: reduce the pump current
protection Coolant temperature: less than
temperature above 102°C Display: Warning appears
100°C
Warning buzzer: Sounds
Work mode: P, E, F, L, B and ATT
Hydraulic oil temperature: less
Hydraulic oil temperature Engine speed: keep as original
Level 2 than 82°C
above 88°C or the coolant Pump current: reduce the pump current
protection Coolant temperature: less than
temperature above 10°C Display: Warning appears
100°C
Warning buzzer: Sounds
Hydraulic oil temperature: less
Work mode: P, E, F, L, B and ATT
than 82°C
Hydraulic oil temperature Engine speed: gear 1st speed
Level 3 Coolant temperature: less than
above 95°C or the coolant Pump current: pump current in 1st gear
protection 100°C
temperature above 108°C Display: Warning appears
Accelerator knob: back to the 1st
Warning buzzer: Sounds
gear position for once
 3-181
December 30, 2017 3.6 Electrical System
CLG930E/936E 3.6.3 Electrical Control System

3.6.3.5 Traveling Speed Control 2. When the travel speed is high, the main
Function controller will change the travel speed
automatically based on the pressure output
by the pump. If the pump pressure is higher
than 28MPa for at least 1s, the travel speed
Display will be changed as slow speed automatically.
If the pump pressure is less than15MPa for at
least 1s, the traveling rotate speed will
(Travel speed automatically recover to high speed.
CAN bus command)

Travel speed
Switch signal of
pedal pilot pressure
High speed
P1 pump pressure signal
Main controller
P2 pump pressure signal

Travel speed solenoid valve control signal

Low speed

Pump output pressur

Travel speed solenoid valve

Function:

The machine travel speed can be changed

artificially and can also be changed automatically
based on the pump pressure during travel.
1. Operate the travel speed control button on
the display to switch between the low speed
and high speed.
3-182
3.6 Electrical System December 30, 2017
3.6.3 Electrical Control System CLG930E/936E

3.6.3.6 Various ComponentS Refer to the following table for the corresponding
relation between the temperature sensor
Pressure Switch resistance and the temperature:

Resistance (Ω) Temperature(°C)

169 150
191 145
215 140
244 135
277 130
316 125
361 120
414 115
476 110
549 105
1. Switch
2. Connector 637 100
Resistor type temp sensor 741 95
865 90
1015 85
1195 80
1678 70
2401 60
3509 50
10000 25
12000 20
14800 15
19300 10
25000 5
1. Seal ring 31400 0
2. Sensor
3. Connector 40000 -5
52000 -10
69000 -15
95000 -20
138100 -25
188500 -30
261500 -35
361100 -40
 3-183
December 30, 2017 3.6 Electrical System
CLG930E/936E 3.6.3 Electrical Control System

Voltage type pressure transmitter

The relation between the 500 bar pressure
sensor output current and the pressure is as the
following figure:

Voltage / V

Pressure/bar

1. COMBINATION CUSHION
2. Sensor
3. Connector Door control switch
The relation between the 50 bar pressure sensor
output current and the pressure is as the
following figure:

Voltage / V

Pressure/bar

1. Switch
2. Connector
3-184
3.6 Electrical System December 30, 2017
3.6.3 Electrical Control System CLG930E/936E

Fuel Level Sensor

A-direction

B-direction

1. Block
2. Floater
3. Connector
 3-185
December 30, 2017 3.6 Electrical System
CLG930E/936E 3.6.3 Electrical Control System

Fuel level

Floater Output
Percentage
Floater Output position resistance (Ω)
Percentage
position resistance (Ω) 70% L14-L15 400±4
0% Below L1 1100±11 75% L15-L16 350±3.5
5% L1-L2 1050±10.5 80% L16-L17 300±3
10% L2-L3 1000±10 85% L17-L18 250±2.5
15% L3-L4 950±9.5 90% L18-L19 200±2
20% L4-L5 900±9 95% L19-L20 150±1.5
25% L5-L6 850±8.5 100% L20-L21 100±1
30% L6-L7 800±8
35% L7-L8 750±7.5
40% L8-L9 700±7
45% L9-L10 650±6.5
50% L10-L11 600±6
55% L11-L12 550±5.5
60% L12-L13 500±5
65% L13-L14 450±4.5
3-186
3.6 Electrical System December 30, 2017
3.6.3 Electrical Control System CLG930E/936E

Accelerator knob

Lead Pin
Power line
Slot
Earthing cable
Signal line

Connector: DEUTSCH DT04-3P

Working temperature: -40°C~+85°C. Output type: PWM

Working voltage: 5V±0.25V Output current (MAX): 20mA

Corresponding parameters and specifications of each gear

Pulse width
Accelerator gear Rotation angle (°) Voltage (V)
(accuracy±3.2%)
1 10.0 0 0.51~0.52
2 17.27 13.63 0.89~0.90
3 24.55 27.27 1.25~1.26
4 31.82 40.91 1.61~163
5 39.09 54.55 1.97~1.99
6 46.36 68.18 2.34~2.35
7 53.64 81.82 2.71~2.72
8 60.91 95.45 3.07~3.08
9 68.18 109.09 3.43~3.45
10 75.45 122.73 3.80~3.82
11 82.73 136.36 4.16~4.19
12 90.0 150 4.52~4.53
 3-187
December 30, 2017 3.6 Electrical System
CLG930E/936E 3.6.3 Electrical Control System

Controller

Black White

LG922E930E3195
3-188
3.6 Electrical System December 30, 2017
3.6.3 Electrical Control System CLG930E/936E

1. J1

Pin Input and output port

Signal name Description
number function
1 Travel alarm buzzer High level output Output 24V to the buzzer
2 Battery is always energized Battery voltage 24V, always connect with the battery
3 Battery is always energized Battery voltage 24V, always connect with the battery
4 Battery is always energized Battery voltage 24V, always connect with the battery
5 Battery is always energized Battery voltage 24V, always connect with the battery
6 Battery is always energized Battery voltage 24V, always connect with the battery
7 NCa - The pin is not adopted
8 Handle pilot pressure switch Number input Low level is valid
9 NC - The pin is not adopted
High level is valid, and input 24V when
10 Engine starting Number input the start switch is turned to "start"
position
Input 24V when the start switch is
11 Power on Number input
turned to "on" position
12 NC - The pin is not adopted
13 Transient power boost solenoid valve High level output Output 24V to drive solenoid valve
14 Power grounding Grounding
15 Power grounding Grounding
16 Power grounding Grounding
17 Power grounding Grounding
18 Hoist overload pressure Analog input Input 4 ~ 20mA
19 NC - The pin is not adopted
20 Hydraulic oil level warning switch Number input Low level is valid
21 NC - The pin is not adopted
22 Boom light signal input Number input High level is valid
23 CAN Shield CAN Shield
24 Power Supply Relay High level output Output 24V to drive the relay
25 Trenching function solenoid valve High level output Output 24V to drive solenoid valve
26 Travel lifting solenoid valve High level output Output 24V to drive solenoid valve
27 Flattening solenoid valve High level output Output 24V to drive solenoid valve
28 5V power supply Sensor power supply Output 5V voltage
29 12-Gear accelerator potentiometer Frequency input PWM signal of variable duty ratio
30 NC - The pin is not adopted
31 NC - The pin is not adopted
32 NC - The pin is not adopted
33 CAN Low CAN Low
34 CAN High CAN High
35 NC - The pin is not adopted
a. NC indicates that the stitch is not adopted.
 3-189
December 30, 2017 3.6 Electrical System
CLG930E/936E 3.6.3 Electrical Control System

2. J2

Pin Input and output port

Signal name Description
number function
Form circuit with J2-5 and control the
1 Pump solenoid current feedback Low level output
pump proportional solenoid valve
2 NCa - The pin is not adopted
3 Power boosting switch Number input Low level is valid
4 NC - The pin is not adopted
Output PWM signal and control the
5 Pump solenoid current High level output
pump proportional solenoid valve
6 Refueling pump relay High level output Output 24V to drive the relay
7 NC - The pin is not adopted
Accessory adjusting proportional
8 High level output Output PWM signal
solenoid 2
Accessory adjusting proportional
9 High level output Output PWM signal
solenoid 1
It is low speed when 0V is output and
10 Travel switching solenoid valve High level output
high speed when 24V is output
11 NC - The pin is not adopted
12 ATT solenoid valve High level output Output 24V to drive solenoid valve
13 Pedal pressure switch Number input Low level is valid
14 NC - The pin is not adopted
15 NC - The pin is not adopted
16 NC - The pin is not adopted
17 Manual preheating switch Number input High level is valid
18 NC - The pin is not adopted
19 N1 Negative flow pressure Analog input Input 4 ~ 20mA
20 Pump proportional solenoid valve Analog input Input 4 ~ 20mA
21 NC - The pin is not adopted
22 Sensor grounding Sensor grounding
23 Start cut-off valve relay High level output Output 24V to drive the relay
Form circuit with J2-8 and J2-9 and
Pq1 & Pq2 flow adjustment solenoid
24 Low level output control the auxiliary adjustment
valve
proportional solenoid valve 1 and 2
25 Subsidiary secondary pressure switch Number input Low level is valid
26 Engine oil level switch Number input Low level is valid
27 Intake air filter alert Number input Low level is valid
High level is valid, which is connected
28 Battery charging indicator switch Number input
to the P point of the engine
29 NC - The pin is not adopted
0 ~ 5V voltage signal (signal
30 Fuel level Analog input
transformation is weak)
31 P1 left pump pressure Analog input Input 4 ~ 20mA
3-190
3.6 Electrical System December 30, 2017
3.6.4 Descriptions of Partial Circuits CLG930E/936E

Pin Input and output port

Signal name Description
number function
32 P2 right pump pressure Analog input Input 4 ~ 20mA
33 N2 Negative flow pressure Analog input Input 4 ~ 20mA
34 NC - The pin is not adopted
35 NC - The pin is not adopted
a. NC indicates that the stitch is not adopted.

3.6.4 Descriptions of Partial Circuits

3.6.4.1 Travel Two-Speed Circuit

When the travel speed control key on the display is pressed, the J2-10 pin of the main controller will
output 24V voltage to the travel transmission solenoid valve coil to make the travel speed switch to the
high-speed state.
When the travel speed control key on the display is pressed again, the J2-10 pin of the main controller
will output 0V voltage to the travel transmission solenoid valve coil to make the travel speed switch to the
low-speed state.
 3-191
December 30, 2017 3.6 Electrical System
CLG930E/936E 3.6.4 Descriptions of Partial Circuits

3.6.4.2 Transient Pressure Boosting Circuit

When the transient power boosting button is pressed, the J1-13 pin of the main controller (IPC controller)
will output 24V voltage to the power boosting solenoid valve for 8s, and then the button will reset
automatically, namely, the J1-13 pin of the main controller (IPC controller) outputs 0V voltage to the
power boosting solenoid valve. 10s later, whether the power boosting function is enabled depends on if
the transient power boosting button is pressed.
3-192
3.6 Electrical System December 30, 2017
3.6.4 Descriptions of Partial Circuits CLG930E/936E

3.6.4.3 Start Circuit

 3-193
December 30, 2017 3.6 Electrical System
CLG930E/936E 3.6.4 Descriptions of Partial Circuits

When the electric lock (also called as ignition switch) is turned to "On" position, the battery relay coil
circuit is conducted, making the battery relay main contact closed, and the main controller and the
engine controller are powered on to work.
When the electric lock is turned to Start position, the starter relay K1 coil circuit is conducted, making the
starter relay K1 main contact closed, and then the engine is started.
When the electric lock is turned to the "Start" position, the pilot shut-off valve switch will always be in
closed state and the safety relay K10 main contact will be closed making the pilot control starter relay K7
main contact closed.
When the electric lock is turned to the "Start" position and the starting signal is detected by the main
controller, the J2-23 pin of the main controller will output 0V voltage to the controller control starter relay
K8 coil, making the controller control starter relay K8 main contact always in closed state.
1. Starter motor circuit:
"Battery positive-battery relay main contact -50A fuse-starting relay K1 main contact-starting motor
starting end-starting motor-grounding"
2. Battery relay coil circuit
"Battery terminal positive - 50A fuse - Electric lock power supply 20A fuse (fuse box) - ignition
switchB1end - ignition switch B2 end - battery relay coil - earthing"
3. Starting relay K1 coil circuit:
3-194
3.6 Electrical System December 30, 2017
3.6.4 Descriptions of Partial Circuits CLG930E/936E

"Battery positive -50A fuse-electric lock power 20A fuse (fuse box)-ignition switch B1 end-ignition switch
S end-pilot control starting relay K7 main contact (fuse box)-controller control starting relay K8 main
contact (fuse box)-starting relay K1 coil-grounding"
4. Pilot control starter relay K7 coil circuit:
"Battery positive-battery relay main contact- -50A fuse - pilot stop 10A (fuse box) - safety relay K10 main
contact (fuse box)-pilot stop valve switch main contact point-pilot control starting relay K7 coil (fuse box)-
grounding"
5. Starter relay K10 coil circuit:
"Battery positive -50A fuse-electric lock power 20A fuse (fuse box)-ignition switch B1 end-ignition switch
B2 end-safety relay K10 coil (fuse box) -grounding"
6. Controller control starter relay K8 coil circuit:
"Controller-J2-23 pin - controller control starting relay K8 coil (fuse box)-grounding"
Note: When the electric lock is turned to "On" position, the B1 end and the B2 end of the ignition switch
are conducted. When the electric lock is turned to "Start" position, the end B1 and the end B2 of the
ignition switch are conducted with the end S.

3.6.4.4 Trenching Function Circuit

 3-195
December 30, 2017 3.6 Electrical System
CLG930E/936E 3.6.4 Descriptions of Partial Circuits

When the trenching function key on the display is pressed, the J1-25 pin of the main controller (IPC
controller) outputs 24V voltage to the trenching solenoid valve coil.
When the trenching function key on the display is pressed again, the J1-25 pin of the main controller
(IPC controller) outputs 0V voltage to the trenching function solenoid valve coil.
Note: the trenching function is only available under the P, E and F mode.
When the trenching function is enabled. The trenching solenoid valve is powered on, and the swing logic
valve is in the maximum opening when the boom is operated upward. Namely, the swing speed is not
restricted. That is what we often called the swing has the priority to the boom lifting.
When the trenching function is pressed again. The trenching solenoid valve is powered off, and the
swing logic valve is in the minimum opening when the boom is operated upward. Namely, the swing
speed is restricted. When the lifting and swing operation of the boom are carried out at the same time,
the flow distributed to the boom lifting is larger. That is what we often called the boom lifting has the
priority to the swing.

3.6.4.5 Grader Function Circuit

When the flattening function key on the display is pressed, the J1-27 pin of the main controller (IPC
controller) outputs 24V voltage to the arm speed-2 gear solenoid valve coil.
When the flattening function key on the display is pressed again, the J1-27 pin of the main controller
(IPC controller) outputs 0V voltage to the arm speed-2 gear solenoid valve coil.
3-196
3.6 Electrical System December 30, 2017
3.6.4 Descriptions of Partial Circuits CLG930E/936E

Note: the flattening function is only available under the P, E and F mode.
When the flattening function key is pressed, the flattening solenoid valve coil is powered on. When the
arm logic valve of the arm 2 valve stem is in the maximum opening, the arm speed will increase which
facilitates the grader operation.
When the flattening function key is pressed again, the flattening solenoid valve coil is powered off. When
the arm logic valve of the arm 2 valve stem is in the minimum opening, the arm speed will decrease
which facilitates the loading operation.

3.6.4.6 Charge Circuit

J2-28 pin of the main controller (IPC controller) will monitor the P end of the alternator.
The electric energy outputted from the B end of the alternator charges the battery via the wire 120 and
108 and the battery relay. The PWM signal is output from the P end of the alternator to the main
controller (IPC controller), which is used to judge whether the alternator generates electricity normally. A
light can be installed on the outside of the alternator L end to judge whether the alternator generates
electricity normally. The light will come on when the alternator does not generate electricity. The light will
go off when the alternator generates electricity. Here, we do not judge from the L end, so the L end of the
alternator is suspended.
 3-197
December 30, 2017 3.6 Electrical System
CLG930E/936E 3.6.4 Descriptions of Partial Circuits

3.6.4.7 Working Circuit of the Pump Proportional Solenoid Valve

The main controller (IPC controller) will output PWM signals to the pump proportional solenoid valve
according to the matching strategy of pump power and engine output power.
3-198
3.6 Electrical System December 30, 2017
3.6.4 Descriptions of Partial Circuits CLG930E/936E
 4-1
December 30, 2017 Parameter
CLG930E/936E

Parameter

4.1 Basic Parameters ......................................................................................................4-3

4.2 Performance Parameters of Diesel Engine ..........................................................4-10
4.3 Performance Parameters of Complete Machine ..................................................4-11
4-2
Parameter December 30, 2017
CLG930E/936E
 4-3
December 30, 2017 4.1 Basic Parameters
CLG930E/936E

4.1 Basic Parameters

The machine is applicable for digging and loading the earth of levels I - IV (the earth and rock are divided
into 16 levels in accordance with the digging difficulty, in which the earth level is below IV level).
According to the requirements of different engineering operations, this machine can also be installed
with backhoe shovel, crowd shovel, hydraulic breaker, plum claw and other various work implements.
Altitude: ≤3048m
Ambient temperature: -32 °C ~ 45°C
Fording depth: no matter what kind of position (horizontal or slope) the machine is located in, the fording
depth is not allowed to exceed the center of the carrier roller.

Main Technical Parameters

All rated operations of the machine are obtained when the machine operates on a hard and horizontal
supporting surface. If the working ambient conditions of the machine differ from the above standard
conditions (for example, working on soft or uneven ground or slopes), the operator shall consider these
conditions.

Overall Dimension Drawing

4-4
4.1 Basic Parameters December 30, 2017
CLG930E/936E

Complete Vehicle Parameters

Unit(s) Parameters
Item
CLG930E CLG936E
Engine model Cummins 6C8.3 Cummins 6C8.3
Operating weight kg 31800 35000
Standard bucket capacity m3 1.4 1.6
Travel speed (high/low) km/h 0~5.5, 0~3.0 0~5.5, 0~3.4
Swing speed r/min 10.3 10
Climbing ability 35° (70%) 35° (70%)
Pressure to the ground (track width is 600mm) KPa 60 65.3
J: Overall length mm 10650 11167
Overall width (track width is 600mm) mm 3190 3190
Overall height mm 3525 3530
D:Height of cab roof mm 3175 3175
2995. (excluding side anti- 2995. (excluding side anti-
E:Overall width of the upper platform mm
collision bar) collision bar)
*H: Counterweight ground clearance mm 1215 1172
*C: Minimum ground clearance mm 500 532
I:Tail end length of the upper platform mm 3200 3500
Rotating radius of tail end mm 3230 3500
G:Underframe axle base mm 4050 4050
F:Underframe length mm 4980 4944
A:Underframe track distance mm 2590 2590
B:Underframe width (track width is 600mm) mm 3190 3190
Note: The sizes with * exclude grouser height.
 4-5
December 30, 2017 4.1 Basic Parameters
CLG930E/936E

Components Parameters

Parameters
Components Item Unit(s)
CLG930E CLG936E
Model Cummins 6C8.3 Cummins 6C8.3
Turbo charged and air to
Turbo charged and air to air
Type air inter-cooling/water
inter-cooling/water cooling
cooling
U.S. EPA Tier 2, CARB
U.S. EPA Tier 2, CARB Tier
Emission Tier 2, EU Stage II,
2, EU Stage II, JMLIT Step 2
JMLIT Step 2
Cooling mode Water cooling Water cooling
Ignition sequence 1-5-3-6-2-4 1-5-3-6-2-4
Cylinder bore × stroke mm 114 X 134.9 114 X 134.9
Cylinder displacement L 8.29 8.29
Engine Compression ratio 18:1 18:1
Rated power 160kW/2200RPM 186kW/2200RPM
Net power 148KW 174KW
Maximum torque N.m 975/1500 RPM 1158/1500 RPM
Engine oil level L 26.5 26.5
Net weight of diesel engine kg 617 617
Maximum idling speed r/min 2200 2200
Minimum idling speed r/min 850 1100
Rated fuel consumption rate g/kW.h 244 234
Starter motor 24V-7.8kW 24V-7.8kW
Alternator 24V-70A 24V-70A
4-6
4.1 Basic Parameters December 30, 2017
CLG930E/936E

Components Parameters

Parameters
Components Item Unit(s)
CLG930E CLG936E
Double-axial, full power, Double-axial, full power,
negative flow, electronically negative flow,
Main pump
controlled variable plunger electronically controlled
pump variable plunger pump
Maximum system flow L/min 2×266 2×300
Setting
MPa 34.3 34.3
pressure
Main relief
valve When
instantaneously MPa 37.3 37.3
supercharging
Big cavity/small
MPa 39.2 39.2
Setting cavity of boom
pressure of Big cavity/small
MPa 39.2 39.2
outlet safety cavity of arm
valve Big cavity/small
MPa 39.2 39.2
cavity of bucket
Hydraulic
system Setting pressure of swing motor
MPa 26.2 26.2
relief valve
Setting pressure of travel motor
MPa 34.3 34.3
safety valve
Pilot pump Gear pump Gear pump
Pilot circuit MPa 3.9 3.9
Quantity - bore × rod
Boom mm 2-φ140×φ100×1342 2-φ140×φ100×1505
diameter × stroke
cylinder
Buffer When stretching out When stretching out
Quantity - bore × rod
mm 1-φ150×φ110×1755 1-φ170×φ120×1785
Arm diameter × stroke
cylinder When stretching out and When stretching out and
Buffer
retracting retracting
Quantity - bore × rod
Bucket mm 1-φ140×φ100×1135 1-φ145×φ100×1220
diameter × stroke
cylinder
Buffer When stretching out When stretching out
Work Boom (standard configuration) mm 6200 6400
implement Arm (standard configuration) mm 3050 3200
 4-7
December 30, 2017 4.1 Basic Parameters
CLG930E/936E

Components Parameters

Parameters
Components Item Unit(s)
CLG930E CLG936E
Track shoe width mm 600 600
Track assembly Piece 2 2
Number of track plate (each bar) 48 48
Track tension device Piece 2 2
Travel device
Sprocket Piece 2 2
Guide wheel assembly Piece 2 2
Track roller 9 at each side 9 at each side
Carrier roller 2 at each side 2 at each side
Electrical System voltage V 24 24
System Battery 2×12V 2×12V
Refrigerating capacity W 5000 5000
Cooling air output m3/h 550 550
Heating capacity W 5800 5800
Heating air output m3/h 400 400
Voltage V.DC 24 24
Total power W ≤310 ≤310
Air conditioning
Compressor shaft consumption
system kW 3.02 3.02
power
Refrigerant R134a R134a
Refrigerant filling quantity g 950±50 950±50
10S15C (Denso 10S15C (Denso
Compressor
compressor) compressor)
ND-OIL8 (Denso special ND-OIL8 (Denso special
Refrigeration oil
compressor oil) compressor oil)
4-8
4.1 Basic Parameters December 30, 2017
CLG930E/936E

Scope of work
 4-9
December 30, 2017 4.1 Basic Parameters
CLG930E/936E

Item Unit(s) CLG930E CLG936E

Arm length mm 3050 3200
Boom length mm 6200 6400
*A: Maximum digging height mm 10300 10240
*B: Maximum unloading height mm 7265 7160
*C: Maximum digging depth mm 7300 7340
*E: Maximum vertical digging depth mm 6216 6460
H: Maximum digging radius mm 10653 11100
G: Maximum ground digging radius mm 10453 10900
*D: Maximum digging depth (2.5m horizontal plane) mm 7096 7180
F: Minimum swing radius mm 4040 4465
Maximum digging force of bucket (ISO) kN 203 252
Maximum digging force of arm (ISO) kN 149 185
Note: The sizes with * exclude grouser height.
4-10
4.2 Performance Parameters of Diesel Engine December 30, 2017
CLG930E/936E

4.2 Performance Parameters of Diesel Engine

Parameters
Name
CLG930E CLG936E
Engine model Cummins 6C8.3 Cummins 6C8.3
Turbo charged and air to air inter- Turbo charged and air to air inter-
Form
cooling/water cooling cooling/water cooling
Number of cylinder 6 6
Cylinder diameter x stroke 114mm X 134.9mm 114mm X 134.9mm
Displacement 8.29L 8.29L
Compression ratio 18:1 18:1
Ignition sequence 1-5-3-6-2-4 1-5-3-6-2-4
Rated power 160kW/2200RPM 186kW/2200RPM
Maximum torque 975 N.m /1500 RPM 1158 N.m /1500 RPM
Engine oil volume 26.5L 26.5L
Low idling Minimum allowable values 69kPa Minimum allowable values 69kPa
Engine oil pressure Minimum allowable values 205 Minimum allowable values 205
Rated speed
kPa kPa
Fan 6-Φ813 8-Φ813
Starter motor 24V-7.8kW 24V-7.8kW
Air intake heater 24V-190A 24V-190A
Alternator 24V-70A 24V-70A
Intake valve 0.30mm 0.30mm
Valve lash
Exhaust valve 0.61mm 0.61mm
Open temperature 84°C 84°C
Thermostat
Full open temperature 91°C 91°C
 4-11
December 30, 2017 4.3 Performance Parameters of Complete Machine
CLG930E/936E

4.3 Performance Parameters of Complete Machine

Performance standard
Item Unit(s)
CLG930E CLG936E
Engine speed (A/C Minimum speed (idling) 1050±30 1100±30
r/min
OFF) Maximum speed (idling) 2150±30 2000±30
Rabbit position/forward 13.1±1.5 12.5±1.5
Rabbit position/backward 13.1±1.5 12.5±1.5
Travel speed Sec/20m
Tortoise position/forward 21.9±2.5 20.9±2.5
Tortoise position/backward 21.9±2.5 20.9±2.5
Tortoise position/
34.5±2.5 32.5±2.5
forward
Tortoise position/
34.5±2.5 32.5±2.5
backward
Left track
Rabbit position/
20.5±1.5 19.5±1.5
forward
Rabbit position/
20.5±1.5 19.5±1.5
Travel speed backward
Sec/3rev
(Idling speed) Tortoise position/
34.5±2.5 32.5±2.5
forward
Tortoise position/
34.5±2.5 32.5±2.5
backward
Right track
Rabbit position/
20.5±1.5 19.5±1.5
forward
Rabbit position/
20.5±1.5 19.5±1.5
backward
Tortoise position ≤100 ≤150
Travel deviation mm/20m
Rabbit position ≤100 ≤200
Swing speed Sec/3rev 18.5±1.5 18±1.5
Swing service brake Counterclockwise ° ≤130 ≤130
angle Clockwise ° ≤130 ≤130
Swing bearing Vertical direction mm ≤0.65 ≤0.65
clearance Horizontal direction mm ≤55 ≤55
Stretching of boom cylinder 3.42±0.4 3.4±0.5
Action time of Shrinking of boom cylinder / /
hydraulic cylinder Stretching of arm cylinder 3.07±0.4 3.5±0.5
(turn off A/C, sec
engine speed is Shrinking of arm cylinder 2.49±0.4 3.1±0.5
maximum) Stretching of bucket cylinder 2.28±0.4 2.5±0.5
Shrinking of the bucket cylinder 1.86±0.4 1.9±0.5
4-12
4.3 Performance Parameters of Complete Machine December 30, 2017
CLG930E/936E

Performance standard
Item Unit(s)
CLG930E CLG936E
Retracting of boom cylinder (mm) ≤30 ≤30
Stretching of arm cylinder (mm) ≤30 ≤30
mm/
Cylinder settlement Retracting of arm cylinder (mm) ≤50 ≤50
10min
Retracting of bucket cylinder (mm) ≤50 ≤50

Boom operation lever: normal handle 10±2 10±2

Multi-function handle 12±2 12±2
Arm operation lever: normal handle 10±2 10±2
Multi-function handle 12±2 12±2
Bucket operation lever: normal handle 10±2 10±2
Control force of control Multi-function handle 12±2 12±2
N
lever
Rotation operation lever: normal handle 10±2 10±2
Multi-function handle 12±2 12±2
Travel control lever 17±2 17±2
Travel control pedal (forward) 60±10 60±10
Travel control pedal (backward) 70±10 70±10
Boom operation lever: normal handle 85±3 85±3
Multi-function handle 71±3 71±3
Arm operation lever: normal handle 85±3 85±3
Multi-function handle 71±3 71±3
Control lever stroke Bucket operation lever: normal handle mm 85±3 85±3
Multi-function handle 71±3 71±3
Rotation operation lever: normal handle 85±3 85±3
Multi-function handle 71±3 71±3
Travel control lever 150±10 150±10
Boom lifted, upper frame rotated by 90° on the
sec 4.0±0.5 4.5±0.5
stage with bucket no-load
Check of boom lifting
and swing action The tooth ground clearance after platform is
rotated by 90°and the boom lifting action is mm 7460±200 7200±200
finished
Adjustment of pilot Engine: high idling MPa 3.9~4.1 3.9~4.1
pressure Engine: low idling MPa 3.5~4.1 3.5~4.1
Lifting of the boom MPa 3.9~4.1
Lowering of the boom MPa 3.9~4.1
Retracting of the arm MPa 3.9~4.1
Stretching of arm MPa 3.9~4.1
Secondary pilot Left swing MPa 3.9~4.1
pressure
(Handle full stroke) Right swing MPa 3.9~4.1
Tuck-in of the bucket MPa 3.9~4.1
Stretching of the bucket MPa 3.9~4.1
Forward MPa 3.9~4.1
Backward MPa 3.9~4.1
 4-13
December 30, 2017 4.3 Performance Parameters of Complete Machine
CLG930E/936E

Performance standard
Item Unit(s)
CLG930E CLG936E
Setting pressure of main relief valve MPa 34.3-35.3 34.3-35.3
Pressurization pressure of main relief valve MPa 37.3-38.3 37.3-38.3
Main loop pressure Left swing MPa 26.2-27.2 26.2-27.2
Right swing MPa 26.2-27.2 26.2-27.2
Drive (travel hold pressure) MPa 34.3-35.3 34.3-35.3
Lifting of the boom MPa 39±0.5
Lowering of the boom MPa 39±0.5
Pressure testing of oil Retracting of the arm MPa 39±0.5
port relief valve Stretching of arm MPa 39±0.5
Tuck-in of the bucket (large cavity) MPa 39±0.5
Stretching of the bucket (small cavity) MPa 39±0.5
266×2 (2 300×2 (2
Main pump flow L/min
pumps) pumps)
Swing motor oil draining (drainage) Drainage pressure MPa ≤0.2 ≤0.2
Travel motor oil draining (drainage) Drainage pressure MPa ≤0.2 ≤0.2
4-14
4.3 Performance Parameters of Complete Machine December 30, 2017
CLG930E/936E
 5-1
December 30, 2017 Adjustment and Test
CLG930E/936E

Adjustment and Test

5.1 Performance Test of Complete Machine .................................................................5-3

5.1.1 Diesel Engine Speed ....................................................................................................................5-4
5.1.2 Track Idling Speed ........................................................................................................................5-4
5.1.3 Travel Speed.................................................................................................................................5-5
5.1.4 Travel Deviation ............................................................................................................................5-6
5.1.5 Swing Service Brake Angle...........................................................................................................5-8
5.1.6 Swing Speed .................................................................................................................................5-9
5.1.7 Swing Bearing Clearance ...........................................................................................................5-10
5.1.8 Action Time of Cylinder ...............................................................................................................5-12
5.1.9 Cylinder Settlement.....................................................................................................................5-14
5.1.10 Operating Force of Control Lever .............................................................................................5-15
5.1.11 Control Lever Stroke .................................................................................................................5-16
5.1.12 Boom Lifting and Swing Action .................................................................................................5-16
5.1.13 Pilot Pressure............................................................................................................................5-17
5.1.14 Secondary Pilot Pressure .........................................................................................................5-18
5.1.15 Output Pressure of Solenoid Proportional Valve ......................................................................5-20
5.1.16 Setting Pressure of Main Relief Valve ......................................................................................5-21
5.1.17 Attached List .............................................................................................................................5-24

5.2 Other Tests...............................................................................................................5-27

5.2.1 Adjustment of Valve Lash ...........................................................................................................5-27
5.2.2 Measurement of Blow-by of Crankcase ......................................................................................5-29
5.2.3 Measurement and Adjustment of Track Tension ........................................................................5-33
Measurement of the track tension ..................................................................................................5-33
Adjustment of track tension ............................................................................................................5-34
5.2.4 Inspection and Adjustment of Minus Feedback Pressure N1.....................................................5-35
5.2.5 Inspection and Adjustment of Minus Feedback Pressure N2 .....................................................5-36
5.2.6 Release the Residual Pressure in Hydraulic Oil Lines................................................................5-36
5.2.7 Exhaust of Various Devices ........................................................................................................5-38
5.2.8 Inspection of Diode .....................................................................................................................5-41
5.2.9 Adjustment of Compressor Belt Tensioner .................................................................................5-42
5.2.10 Performance Test of Travel Motors and Reduction Gears........................................................5-43
5-2
Adjustment and Test December 30, 2017
CLG930E/936E
 5-3
December 30, 2017 5.1 Performance Test of Complete Machine
CLG930E/936E

5.1 Performance Test of Complete Machine

The standard data values obtained from the tests involved in this chapter are as follows:
1. The diesel engine meets the China Stage II, the standard speed is as follows:
Model CLG930E Model of diesel engine Cummins 6C8.3

10th
Gears 1st gear 2nd gear 3rd gear 4th gear 5th gear 6th gear 7th gear 8th gear 9th gear 11th gear 12th gear
gear

Idling speed
1050±30 1200±30 1300±30 1400±30 1700±30 1800±30 1900±30 1950±30 2000±30 2050±30 2100±30 2150±30
(r/min)
Mode P

Hold pressure
0~20 100±10 200±10 300±10 520±10 570±10 570±10 580±10 590±10 570±10 570±10 580±10
current (mA)
Idling current 100±1
0~20 100±10 100±10 100±10 100±10 100±10 100±10 100±10 100±10 100±10 100±10
(mA) 0
Idling speed (r/
1050±30 1200±30 1300±30 1400±30 1550±30 1650±30 1780±30 1850±30 1900±30 1950±30 2000±30 2050±30
min)
Mode E

Hold pressure
0~20 100±10 200±10 300±10 410±10 500±10 570±10 570±10 570±10 580±10 580±10 570±10
current (mA)

Idling current
0~20 100±10 100±10 100±10 100±10 100±10 100±10 100±10 100±10 100±10 100±10 100±10
(mA)

Model CLG936E Diesel engine configuration Cummins 6C8.3

Gears 1st gear 2nd gear 3rd gear 4th gear 5th gear 6th gear 7th gear 8th gear 9th gear 10th gear 11th gear 12th gear

Idling speed
1100±30 1200±30 1300±30 1400±30 1600±30 1700±30 1800±30 1850±30 1900±30 1950±30 2000±30 2000±30
(r/min)
Mode P

Hold pressure
0~20 100±20 200±20 300±20 500±20 550±20 610±20 610±20 630±20 630±20 640±20 650±20
current (mA)
Idling current
0~20 100±10 100±10 100±10 100±10 100±10 100±10 100±10 100±10 100±10 100±10 100±10
(mA)

Idling speed (r/

1100±30 1200±30 1300±30 1400±30 1450±30 1550±30 1650±30 1700±30 1750±30 1800±30 1830±30 1860±30
min)
Mode E

Hold pressure
0~20 100±20 200±20 300±20 370±20 420±20 500±20 510±20 510±20 530±20 530±20 540±20
current (mA)

Idling current
0~20 100±10 100±10 100±10 100±10 100±10 100±10 100±10 100±10 100±10 100±10 100±10
(mA)

2. For the standard performance parameters of the complete machine, please see the section 4.3.

Firstly test whether diesel engine speed reaches technical specification before all other tests,
because if the diesel engine speed is not adjusted correctly, the data of all other performances
will be unreliable.
5-4
5.1 Performance Test of Complete Machine December 30, 2017
5.1.1 Diesel Engine Speed CLG930E/936E

5.1.1 Diesel Engine Speed 5.1.2 Track Idling Speed

A. Tools and testing instruments A. Tools and testing instruments

1. Reflective sheeting 1. Stopwatch.

2. Tachometer 2. Tool used for marking starting point.

B. Preparations 3. Test is performed by two people.

Turn off the air conditioner and the automatic B. Machine status and parking site
idling, there is no load, and turn the gear to the
1. Solid and flat parking site.
position to be tested.
2. Maintain hydraulic oil temperature between
C. Test method 45°C and 55°C.
1. Open the diesel engine hood. 3. Set the engine at the maximum speed (turn
off A/C).
2. Stick the reflective sheeting on the output
end of the diesel engine crankshaft or the fan 4. The pump working current is within the
shaft, but it is required to multiply by the normal range.
speed ratio of the fan and the diesel engine 5. The complete machine works in the normal
at this moment. mode.
3. By illuminating the place sticking with 6. The working pressure and the pilot pressure
reflective sheeting with tachometer, diesel of the pump are within the normal range.
engine speed can be obtained from the
instrument. C. Travel speed test
4. Repeatedly measure for 3 times and
1. Park the machine at solid and flat site.
calculate average value.
2. Maintain the hydraulic oil temperature
between 45°C and 55°C.
3. Operate the right swing until the upper
mechanism is vertical to the lower one.
4. Operate the boom, arm and bucket until the
bucket bottom is on the ground.
 5-5
December 30, 2017 5.1 Performance Test of Complete Machine
CLG930E/936E 5.1.3 Travel Speed

5. Lower the boom until the right track is raised 5.1.3 Travel Speed
for about 100 ~ 200 mm from the ground to
keep the track away from the ground during
operation as shown in following picture. Mark A. Tools and testing instruments
on the appropriate position of the track.
1. Stopwatch.
2. Tape (50m).
3. Test is performed by two people.

B. Machine status and parking site

1. Solid and flat parking site.

2. Maintain hydraulic oil temperature between
45°C and 55°C.
3. Set the engine at the maximum speed (turn
off A/C).
4. The pump working current is within the
normal range.
6. Set the accelerator linkage or knob to the
maximum speed position of engine. 5. The complete machine works in the normal
mode.
7. Turn the travel speed selection switch to gear
"1" (tortoise position). 6. The working pressure and the pilot pressure
of the pump are within the normal range.
8. Push the right travel control lever to the front
end, and then measure and record the time C. Travel speed test
for the right track swinging 3 circles.
9. Repeat the steps 7 and 8, and totally 1. Park the machine on a solid and flat site (the
measure three times. Calculate the average flat site for straight travel about 30m).
value of the data based on the three 2. Maintain the hydraulic oil temperature
measurements. between 45°C and 55°C.
10. Measure the data of the right track "1" 3. Operate work implements, and stretch arm,
position (tortoise position) backwards using bucket cylinder, then adjust boom to keep the
the same method. distance between the bucket and the ground
11. Turn the travel speed selection switch to "2" 0.5m high, as shown in the following figure.
position (rabbit position), repeat the steps 8
to 10, and compare the average value of
measured data with the standard values in
the Table below.
12. Lift the boom till the bucket bottom off the
ground 300 mm. Turn left swing and turn the
upper mechanism by 180°.
13. Repeat the steps 4 to 11, and measure the
travel speed of the left track in the same way.
14. Refer to attached table for test table.
5-6
5.1 Performance Test of Complete Machine December 30, 2017
5.1.4 Travel Deviation CLG930E/936E

4. Draw a 30m line on the ground starting from 5.1.4 Travel Deviation
the track front end, and then draw another
line approx. 10m away from the starting point
and make it paralleled with the machine. As A. Tools and testing instruments
shown in the Figure below
1. Tape (30m).
2. Tool used for marking the location of the
machine.

B. Machine status and parking site

1. Solid and flat parking site.

2. Maintain hydraulic oil temperature between
45°C and 55°C.
3. Set the engine at the maximum speed (turn
At the start timing At the end point
off A/C).
4. The pump working current is within the
LG922EIII05003 normal range.
5. The complete machine works in the normal
5. Set the accelerator linkage or knob to the
mode.
maximum speed position of engine.
6. The working pressure and the pilot pressure
6. Turn the travel speed selection switch to gear
of the pump are within the normal range.
"1" (tortoise position).
7. The maximum wind speed shall be no more
7. Driving into the test road, the front 10m of
than 6m/s during the test.
which is for acceleration, at the steady
speed. Starts timekeeping when the front end C. Travel deviation test
of the track enters the timing line and stop it
when the front end of the track reaches the 1. Park the machine at solid and flat site.
finishing line. Record the time for the
2. Maintain the hydraulic oil temperature
machine running through the test road. As
between 45°C and 55°C.
shown in the above Figure.
8. Repeat step 7 to measure 3 times, and
calculate average value of measured data for
three times.
9. Turn the upper mechanism by 180°, and
measure the data of the right track "1"
position backwards (tortoise position) using
the same method.
10. Turn the travel speed selection switch to "2"
position (rabbit position) and repeat steps
6~9.
11. Refer to attached table for test table.
 5-7
December 30, 2017 5.1 Performance Test of Complete Machine
CLG930E/936E 5.1.4 Travel Deviation

3. Operate work implements, stretch boom, arm 7. Push forward the left and right travel control
and bucket cylinder, as shown in Figure lever to the topmost at the same time. The
below. excavator reaches the position about 5m
away from the starting point, where mark A
on the track on the relative location of the
ground. Similarly, mark B and C correctly
when the excavator reaches the position
about 15m away from the starting point and
to the finishing point. As shown in the Figure
below

4. Draw a line of 25m on the ground starting

from the track front end and make the line
paralleled to the machine. Draw a line at
each position about 5m and 15m away from 8. Measure the perpendicular distance "e" of
the front end of excavator track and at the point "B" to straight line AC on the track.
finishing point respectively. 9. Repeat the steps 7 and 8, and totally
5. Set the accelerator linkage or knob to the measure three times. Calculate average
maximum speed position of engine. value of measured data for three times.

6. Turn the travel speed selection switch to gear 10. Turn the travel speed selection switch to gear
"1" (tortoise position). "2" (rabbit position), repeat steps 7~9 and
measure the travel deviation value at gear "2"
(rabbit position).
11. Turn the lower mechanism by 180°, repeat
the steps 3 ~10, and measure the travel
deviation values when the excavator travels
backwards and compare them with the
standard values in the Table below.
12. Refer to attached table for travel deflection
test table.
5-8
5.1 Performance Test of Complete Machine December 30, 2017
5.1.5 Swing Service Brake Angle CLG930E/936E

5.1.5 Swing Service Brake Angle C. Swing service brake angle test

1. Park the machine at a solid and flat site, as

shown in the figure below.

Please confirm that the testing site allows the

machine for 360° swing! Please confirm that
there are no other personnel or facilities
within 3m scope of swing area!

A. Tools and testing instruments

1. Tool used for marking starting point.

2. Measuring tape.
3. Plumb.
4. Measurement is performed by 3 person. 2. Set the accelerator linkage or knob to the
maximum speed position of engine.
B. Machine status and parking site 3. Stretch the arm completely (retract cylinder).
1. Solid and flat parking site. 4. Retract the bucket completely (stretch the
cylinder).
2. Maintain hydraulic oil temperature between
45°C and 55°C. 5. Adjust the boom height until the distance
reaches 1.5m between bucket tooth and the
3. Set the engine at the maximum speed (turn
ground.
off A/C).
6. 3. Confirm the projection point of middle
4. The pump working current is within the
tooth of bucket on the ground with plumb bob
normal range.
and make corresponding mark A, measure
5. The complete machine works in the normal the distance L2 of the projection point to track
mode (and the idling state). front end, and get the distance L1 of swing
6. The working pressure and the pilot pressure bearing center to track front end, as shown in
of the pump are within the normal range. the figure.
 5-9
December 30, 2017 5.1 Performance Test of Complete Machine
CLG930E/936E 5.1.6 Swing Speed

5.1.6 Swing Speed

Please honk the horn before swing action!

7. After operation is allowed by whistling,
operate swing pilot valve to maximum stroke, Please confirm that the testing site allows the
and swing one circle clockwise with fastest machine for 360° swing! Please confirm that
speed. When the bucket arrives at starting there are no other personnel or facilities
position, release pilot valve to make the within 3m scope of swing area!
machine stop operating naturally.
8. Measure the distance between A and B with A. Tools and testing instruments
the tape (chord length which swing angle
corresponds to), as shown in figure below: 1. Stopwatch.
2. Tool used for marking starting point.
3. Two test personnel that are skillful at
operating the excavator.

B. Machine status and parking site

1. Solid and flat parking site.

2. Maintain hydraulic oil temperature between
45°C and 55°C.
3. Set the engine at the maximum speed (turn
off A/C).
4. The pump working current is within the
normal range.
5. The complete machine works in the normal
9. Repeat the steps 6 and 7, measure three
mode.
times in total and calculate the average
value. 6. The working pressure and the pilot pressure
of the pump are within the normal range.
10. Measure the distance between A and B
during anticlockwise swing with the same C. Swing speed test
method.
11. Refer to attached table for swing service 1. Park the machine at solid and flat site.
brake angle test table. 2. Set the accelerator linkage or knob to the
maximum speed position of engine.
3. Stretch the arm completely (retract cylinder).
4. Retract the bucket completely (stretch
cylinder).
5-10
5.1 Performance Test of Complete Machine December 30, 2017
5.1.7 Swing Bearing Clearance CLG930E/936E

5. Adjust the boom height to make the bottom of 5.1.7 Swing Bearing Clearance
the bucket at the height of boom hydraulic
cylinder articulated axle, as shown in Figure
Below. 1. Swing bearing clearance (vertical
direction)

A. Tools and testing instruments

1. Dial indicator.
2. Dial indicator bracket (can be rotated freely).
3. Tape measure.
4. Measurement is performed by two people.

B. Machine status and parking site

1. Solid and flat parking site.

2. Maintain hydraulic oil temperature between
45°C and 55°C.
3. Set the engine at the maximum speed (turn
Please honk the horn before swing action! off A/C).
4. The pump working current is within the
6. After operation is allowed by whistling,
normal range.
operate swing right pilot valve to maximum
stroke, swing clockwise with fastest speed, 5. The complete machine works in the normal
start timekeeping from third circle, record the mode.
time for three circles in total, and then stop
6. The working pressure and the pilot pressure
swing.
of the pump are within the normal range.
7. Repeat the steps 3~6 and totally measure
three times. Calculate average value of the
measured clockwise swinging time for three
times.
Pay close attention to the machine
8. Measure the time of anticlockwise swinging 3 conditions when reading the dial indicator!
circles with the same method. During maintenance and test, the qualified
protective suit, safety shoes and helmet must
9. Refer to attached table for swing speed test
be worn. Make sure that there are no barriers
table.
within the maximum swing radius.
 5-11
December 30, 2017 5.1 Performance Test of Complete Machine
CLG930E/936E 5.1.7 Swing Bearing Clearance

C. Measurement of swing bearing clearance 8. Release the bucket completely, and lift or
(vertical direction) lower the boom so that the bucket tooth is off
the ground about 450mm as shown in Figure
1. Park the machine at solid and flat site. below.
2. As shown in the Figure below, install magnet
base on swing bearing support, and the
probe of dial indicator contacts mounting bolt
of swing bearing outer ring.

In front of machine

9. Record the readings of dial indicator.

Magnet base
10. Repeat the steps 3~9 and totally measure
Dial
indicator
three times. Calculate average value of
measured data for three times.
11. Turn the upper mechanism by 180°, repeat
3. Retract or stretch the arm to make the the steps 2~10, and measure the vertical
included angle between the arm and the clearance of swing bearing of other side.
boom is about 90°.
12. Refer to attached list for swing bearing
4. Retract or stretch the bucket to make bucket clearance (vertical direction)
bottom parallel with the ground.
5. Lower the boom to make bucket bottom
touch the ground. Continue to lower the
boom, and jack up front end of the machine
so that the track is off the ground about
450mm as shown in Figure below.

6. Place the pointer of dial indicator to position

"0".
7. Lift boom and release arm till stretch the arm
completely.
5-12
5.1 Performance Test of Complete Machine December 30, 2017
5.1.8 Action Time of Cylinder CLG930E/936E

5.1.8 Action Time of Cylinder 2. Set the accelerator linkage or knob to the
maximum speed position of engine.
3. The height of bucket tooth is in accordance
with that of the front pin of the arm.
4. The arm cylinder retracts completely.
Be sure to move the machine (with standard
configuration) out of the route of other
machines before test, in order to ensure that
there is no obstacle within the maximum
swing radius. Other personnel cannot
approach the machine when the machine is
stated for adjustment or test.

When measuring the action time of cylinder,

only measure the time to the cushioning
stroke starting point.

A. Tools and testing instruments

5. Lower the boom till the bucket touching the
1. Stopwatch. ground.
2. Two test personnel that are skillful at 6. Operate the boom and lift the pilot valve to
operating the excavator. (1 excavator the maximum stroke and lift the boom at the
operator and 1 timekeeper / recorder) fastest speed. The timekeeper starts
timekeeping once he or she sees the boom is
B. Machine status and parking site acting, and records the time from action
starting to boom cylinder reaching the
1. Solid and flat parking site. cushioning stroke starting point.
2. Maintain hydraulic oil temperature between 7. Operate the boom and lower the pilot valve to
45°C~55°C (subject to the temperature on the maximum stroke, and lower the boom at
the display, similarly hereinafter). the fastest speed. The timekeeper starts
3. Set the engine at the maximum speed (turn timekeeping once he or she sees the boom is
off A/C). acting, and records the time from action
starting to bucket touching the ground.
4. The pump working current is within the
normal range. 8. Repeat the steps 6 and 7, and totally
measure three times. Respectively calculate
5. The complete machine works in the normal
average values of the boom lifting & lowering
mode. time for three times.
6. The working pressure and the pilot pressure 9. Refer to attached table for boom cylinder
of the pump are within the normal range.
action time test table.
C. Measurement of the boom cylinder action
time

1. Park the machine at solid and flat site.

 5-13
December 30, 2017 5.1 Performance Test of Complete Machine
CLG930E/936E 5.1.8 Action Time of Cylinder

D. Measurement of the arm cylinder action 7. Operate arm pilot valve to the maximum
time stroke and release the arm at the fastest
speed (the cylinder retracts). The timekeeper
begins to time as soon as the arm is acting,
and records the time from action start to arm
cylinder reaching buffer stroke starting point.
This test method is for excavator of standard
configuration. If the tested machine 8. Repeat the steps 6 and 7, and totally
equipment has optional configuration, check measure three times. Calculate the average
and confirm that there is no interferences values of time for arm retracting and
between the frontal attachments and the cab! stretching out for three times respectively
and compare them with the standard values
1. Park the machine at solid and flat site. in the Table below.

2. Set the accelerator linkage or knob to the 9. Refer to attached table 7 for arm cylinder
maximum speed position of engine. action time test table.

3. Lift the boom cylinder to certain height. E. Measurement of the bucket cylinder action
time
4. The bucket cylinder must be retracted to
make sure the bucket can't bump against the 1. Park the machine at solid and flat site.
earthing with arm cylinder is forward and
back. 2. Set the accelerator linkage or knob to the
maximum speed position of engine.
3. Lift the boom to highest position.
4. Adjust the arm to make the angle between
the arm and its cylinder about 90 °.
5. Lower the boom till the height of the front pin
of arm in accordance with rear pin of the
boom.
6. Retract the bucket completely (stretch the
cylinder).

5. Stretch the arm completely (retract the

cylinder).
6. Operate arm pilot valve to the maximum
stroke and retract the arm at the fastest
speed (stretch the cylinder). The timekeeper
begins to time as soon as the arm is acting,
and records the time from action start to arm
cylinder reaching buffer stroke starting point.
5-14
5.1 Performance Test of Complete Machine December 30, 2017
5.1.9 Cylinder Settlement CLG930E/936E

7. Operate bucket pilot valve to the maximum 5.1.9 Cylinder Settlement

stroke and release the bucket at the fastest
speed (the cylinder retracts). The timekeeper
starts timekeeping once he or she sees the A. Tools and testing instruments
bucket is acting, and records the time from
1. 30cm steel ruler.
action starting to bucket cylinder reaching
cushioning stroke starting point (if any). 2. Stopwatch.
8. Operate bucket pilot valve to the maximum 3. Tape used for marking staring point.
stroke and retract the bucket at the fastest
4. 3m tape measure.
speed (stretch the cylinder). The timekeeper
starts timekeeping once he or she sees the 5. Plumb.
bucket is acting, and records the time from
6. Two test personnel that are skillful at
action starting to bucket cylinder reaching
operating the excavator.
cushioning stroke starting point (if any).
9. Repeat the steps 7 and 8, and totally B. Machine status and parking site
measure three times. Calculate the average
1. Solid and flat parking site.
values of time for bucket stretching out and
retracting for three times respectively and 2. Maintain hydraulic oil temperature between
compare them with the standard values in the 45°C and 55°C.
Table below.
3. The pump working current is within the
10. Refer to the attached table for the bucket normal range.
cylinder action time test table.
4. The complete machine works in the normal
mode.
5. The working pressure and the pilot pressure
of the pump are within the normal range.
Be careful about climbing operation.
6. Engine flameout

C. Measurement of cylinder settlement

1. Park the machine in a solid and flat site and

maintain the hydraulic oil temperature
between 45°C and 55°C.
2. Stretch the arm completely (retract cylinder).
3. Retract the bucket completely (stretch the
cylinder).
 5-15
December 30, 2017 5.1 Performance Test of Complete Machine
CLG930E/936E 5.1.10 Operating Force of Control Lever

4. Adjust the boom height until the distance 9. Repeat step 8 and totally measure three
reaches 1.5m between bucket tooth and the times. Calculate the average value of moving
ground, as shown in the Figure Below. distances of arm cylinder piston rod.
10. Refer to attached table for cylinder settlement
test table.

5.1.10 Operating Force of Control

Lever

A. Tools and testing instruments

Spring balance: range 200N

B. Machine status and parking site

5. Shut down the engine, keep for 10 minutes,
and measure and record the moving 1. Solid and flat parking site
distances of boom, arm, and bucket cylinder
piston and settlement distance of tooth. 2. Shutdown the engine
6. Repeat the steps 4 and 5, and totally C. Measure of control lever operating force
measure three times. Respectively calculate
the average values of the moving distances 1. Make spring balance hook on control lever as
of boom, arm, and bucket cylinder piston and shown in Figure below and operate the
settlement distance of tooth for three times. following functions: boom lifting and lowering,
arm retracting and stretching out, bucket
7. Bucket cylinder and arm cylinder is stretched
retracting and stretching out, left and right
completely, and the boom is lowered to
swing and travel
certain height to make articulated joint
between link and bucket cylinder is
250~300mm off the ground, as shown in
Figure Below.

2. Measure the maximum operating force when

each actuating mechanism is in maximum
8. Shut down the engine, keep 10 minutes, and stroke.
measure and record moving distance of arm 3. Record measurement data.
cylinder piston.
4. Repeatedly measure for 3 times and
calculate average value.
5-16
5.1 Performance Test of Complete Machine December 30, 2017
5.1.11 Control Lever Stroke CLG930E/936E

5.1.11 Control Lever Stroke 5.1.12 Boom Lifting and Swing

Action
A. Tools and testing instruments
A. Tools and testing instruments
Steel ruler
1. Stopwatch
B. Machine status and parking site
2. Tape measure
1. Solid and flat parking site
B. Machine status and parking site
2. Shut down the diesel engine.
1. Solid and flat parking site
C. Measure of control lever stroke
2. Set accelerator linkage or knob to maximum
1. Measure the control lever stroke from neutral position of engine speed, lift the boom
position to ending point respectively at the cylinder and make sure that the cylinder runs
tops of boom, arm, bucket, swing and travel smoothly without collision.
control levers.
3. Stretch the arm completely, retract the bucket
2. Repeatedly measure for 3 times and completely, and lower the bucket to the
calculate average value. ground without load. As shown in Figure
3. Record measurement value. below:

4. Maintain hydraulic oil temperature at 50±5°.

C. Inspection of boom lifting and swing

action

1. Set the accelerator linkage or knob to the

maximum speed position of engine. Turn off
the A/C and turn off the automatic idling.
 5-17
December 30, 2017 5.1 Performance Test of Complete Machine
CLG930E/936E 5.1.13 Pilot Pressure

2. Conduct full-stroke operation while lifting 5.1.13 Pilot Pressure

boom and conducting swing. As shown in
Figure below:

If the cab display screen of your machine has

the setting of pressure display, you can use
the information on display screen to conduct
the following tests. If your machine does not
support the function, the following operation
steps will guide you how to install a pressure
gauge.

A. Tools and testing instruments

3. When upper mechanism swings by 90°, Pressure gauge, with measuring range
release control lever to stop these two kinds 0~10MPa;
of actions, as shown in Figure below.
Measure the time of swinging by 90° and the B. Machine status and parking site
height of bucket tooth (H).
1. Solid and flat parking site
2. Maintain hydraulic oil temperature at 50±5°C

C. Measurement of pilot pressure

1. Install the pressure gauge. Specific

operations are as follows
a. Release the residual pressure in oil tank:
Turn off the diesel engine, and loosen the dust
cover on the breather valve, as shown in Figure
below:

4. Repeatedly measure for 3 times and

calculate average value.

Dust cover
5-18
5.1 Performance Test of Complete Machine December 30, 2017
5.1.14 Secondary Pilot Pressure CLG930E/936E

Press the air-bleed valve stem on the breather 5.1.14 Secondary Pilot Pressure
valve, as shown in the figure below:

Press the exhaust

If the cab display screen of your machine has
valve stem the setting of pressure display, you can use
the information on display screen to conduct
the following tests. If your machine does not
support the function, the following operation
steps will guide you how to install a pressure
gauge.

A. Tools and testing instruments

b. Connect the pressure gauger at position 5. Pressure gauge, with measuring range
Figure (1) below. 0~10MPa;
6. Tee (material No. 32C0411)

B. Machine status and parking site

1. Solid and flat parking site

2. Maintain hydraulic oil temperature at 50±5°C

C. Measurement of secondary pilot pressure

1. Install the pressure gauge. Specific

operations are as follows:
a. Release the residual pressure in oil tank:
Turn off the diesel engine, and loosen the dust
cover on the breather valve, as shown in Figure
c. Start the diesel engine, and confirm there
below:
is no obvious oil leakage at the connection
of pressure gauge.
2. Set the accelerator linkage or knob to the
maximum speed position of engine. Turn off
the A/C and turn off the automatic idling.
3. Record the pressure value.
Dust cover
4. Repeatedly measure for 3 times and
calculate average value.
 5-19
December 30, 2017 5.1 Performance Test of Complete Machine
CLG930E/936E 5.1.14 Secondary Pilot Pressure

Press the air-bleed valve stem on the breather 2. Set the accelerator linkage or knob to the
valve, as shown in the figure below: maximum speed position of engine. Turn off
the A/C and turn off the automatic idling.
3. Full-stroke operates the corresponding
control lever and measures the pilot
pressure, including:
Press the exhaust
valve stem
a. Boom lifting and lowering
b. Arm retracting and stretching
c. Bucket retracting and stretching
d. Left and right swing
e. Forward and backward travel
4. Operate control lever and record
measurement value.
b. Connect the pressure gauge. Connect the 5. Repeatedly measure for 3 times and
tee (material No. 32C0411) and pressure calculate average value.
gauge in the pilot line. Start the diesel
engine, and confirm there is no obvious oil
leakage at the connection of pressure
gauge.

1. Pressure gauge
2. Secondary pilot hose
5-20
5.1 Performance Test of Complete Machine December 30, 2017
5.1.15 Output Pressure of Solenoid Proportional Valve CLG930E/936E

5.1.15 Output Pressure of Turn off the diesel engine, and loosen the dust
cover on the breather valve, as shown in Figure
Solenoid Proportional Valve below:

If the cab display screen of your machine has

the setting of pressure display, you can use
the information on display screen to conduct
Dust cover
the following tests. If your machine does not
support the function, the following operation
steps will guide you how to install a pressure
gauge.

A. Tools and testing instruments

1. Transition joint (Material No. 00A0969)

Press the air-bleed valve stem on the breather
2. O-ring (Material No.: 12B0428)
valve, as shown in the figure below:
3. Pressure gauge, with measuring range
0~10MPa

B. Machine status and parking site

Press the exhaust
1. Solid and flat parking site. valve stem

2. Maintain hydraulic oil temperature at 50±5°C.

C. Measurement of output pressure of

solenoid proportional valve

1. Install the pressure gauge. Specific

operations are as follows:
a. Release the residual pressure in oil tank:
 5-21
December 30, 2017 5.1 Performance Test of Complete Machine
CLG930E/936E 5.1.16 Setting Pressure of Main Relief Valve

b. Remove the plug from the main pump, 5.1.16 Setting Pressure of Main
refer to the following Figure for the
position. Connect the O-ring (Material No.:
Relief Valve
12B0428) and transition joint (Material No.:
00A0969), and then connect the pressure
gauge.

If the cab display screen of your machine has

the setting of pressure display, you can use
the information on display screen to conduct
the following tests. If your machine does not
support the function, the following operation
steps will guide you how to install a pressure
gauge.
Pressure tap for
proportional
pressure-reducing valve
outlet pressure
A. Tools and testing instruments

5. Tee (material No. 32C0529)

c. Start the diesel engine, and confirm there 6. O-ring (12B0428)
is no obvious oil leakage at the connection
of pressure gauge. 7. Transition joint (00A1964)

2. Set the accelerator linkage or knob to the 8. Pressure gauge, with measuring range
maximum speed position of engine. Turn off 0~10MPa
the A/C and turn off the automatic idling.
B. Machine status and parking site
3. Full-stroke operation of corresponding
control lever and measurement of the 1. Solid and flat parking site.
pressure of the solenoid proportional valve, 2. Maintain hydraulic oil temperature at 50±5°C.
include:
a. Boom lifting and lowering C. Measurement of output pressure of
solenoid proportional valve
b. Arm retracting and stretching
c. Bucket retracting and stretching 1. Install the pressure gauge. Specific
operations are as follows:
d. Left and right swing
(1) Release the residual pressure in oil tank:
e. Forward and backward travel
4. Repeatedly measure for 3 times and
calculate average value.
5-22
5.1 Performance Test of Complete Machine December 30, 2017
5.1.16 Setting Pressure of Main Relief Valve CLG930E/936E

Turn off the diesel engine, and loosen the dust g. Start the diesel engine, and confirm there
cover on the breather valve, as shown in Figure is no obvious oil leakage at the connection
below: of pressure gauge.
The method for connecting right pump with the
pressure gauge is the same as that of left pump.

Dust cover

Pressure test port

of right pump

Pressure test port

of left pump
Port A

Press the air-bleed valve stem on the breather

Port B

valve, as shown in the figure below:

1. Plug on the pump (originally 3. Transition joint
equipped on the pump) 4. Tee
2. O-ring

Press the exhaust

valve stem

(2) Connect the pressure gauge (take the left

pump as an example):
a. Unscrew the plug (1) shown in the Figure;
2. Set the accelerator linkage or knob to the
b. Install the O-ring (2); maximum speed position of engine. Turn off
c. Install the transition joint (3); the A/C and turn off the automatic idling.
d. Install the tee (4); 3. Slowly operate control levers of bucket, arm,
and boom to maximum strokes, at the
e. Connect the sensor of electrical system
moment, hydraulic system overflows, and
into port A of tee;
measure and record pressure value.
f. Connect the pressure measurement joint
4. For swing function, make upper revolving
into port B of tee.
frame fixed, and slowly operate the swing
control lever in order to make swing function
overflow. Record measurement value.
 5-23
December 30, 2017 5.1 Performance Test of Complete Machine
CLG930E/936E 5.1.16 Setting Pressure of Main Relief Valve

5. For the travel function, fix the track on the

immobile object to make the travel function
overflow. Record measurement value.
6. Press the transient boost switch, operate the
bucket, arm and boom control lever slowly
within 8s to the maximum stroke to make the
hydraulic system overflow, and then measure
and record the pressure value.
5-24
5.1 Performance Test of Complete Machine December 30, 2017
5.1.17 Attached List CLG930E/936E

5.1.17 Attached List

Attached table 1

Travel speed (idling speed/actual measurement speed) test table

Model of complete machine: Testing date:
Number of complete machine: Testing site:
Testing personnel:

Traveling Traveling time (s)

Speed
Testing items distance Average Remarks
1 2 3 (m/s)
(m) value
Forward gear I
Forward gear II Hydraulic oil
Idling
temperature at initial
speed Backward gear I measurement: °C
Backward gear II
Forward gear I
Forward gear II Hydraulic oil
Travel
temperature at initial
speed Backward gear I measurement: °C
Backward gear II

Attached table 2

Travel deviation measurement table

Model of complete machine: Testing date:
Number of complete machine: Testing site:
Testing personnel:

Deviation (mm)
Testing items Average Remarks
1 2 3
value
Forward gear I
Forward gear II Hydraulic oil temperature at
Travel deviation value initial measurement:
Backward gear I °C
Backward gear II
 5-25
December 30, 2017 5.1 Performance Test of Complete Machine
CLG930E/936E 5.1.17 Attached List

Attached table 3

Swing service brake angle test table

Model of complete machine: Testing date:
Number of complete machine: Testing site:
Testing personnel:

AB chord length (mm)

L1+ L2 Swing brake
Testing items Average Remarks
(mm) 1 2 3 angle (°)
value
Clockwise Hydraulic oil temperature at
Counterclockwise initial measur5ement: °C

Attached table 4

Swing speed test table

Model of complete machine: Testing date:
Number of complete machine: Testing site:
Testing personnel:

Swing time(s) Swing

Swing
Testing items Average speed Remarks
circles 1 2 3
value (s/circle)

Clockwise Hydraulic oil temperature at

Counterclockwise initial measurement: °C

Attached table 5

Measurement table of the swing bearing clearance

Model of complete machine: Testing date:
Number of complete machine: Testing site:
Testing personnel:

Swing bearing clearance (mm)

Testing items Remarks
1 2 3 Average value
Hydraulic oil temperature at initial
Vertical direction
measurement: °C
5-26
5.1 Performance Test of Complete Machine December 30, 2017
5.1.17 Attached List CLG930E/936E

Attached table 6

Action time measurement table for excavator work implement

Model of complete machine: Testing date:
Number of complete machine: Testing site:
Testing personnel:

Measured value
Testing Working condition Standard
Average Remarks
items for measurement 1 2 3 requirements
value
Lifting
Boom
Lowering
Hydraulic oil
Action time of Retracting temperature at
the work Arm
Stretching initial
implement (s)
measurement: °C
Excavation
Bucket
Unloading

Attached table 7

Cylinder settlement table

Model of complete machine: Testing date:
Number of complete machine: Testing site:
Testing personnel:

Cylinder settlement (mm)

Testing time
Testing items Average Remarks
(min) 1 2 3
value
Lowering of the boom
Retracting of the arm
Hydraulic oil temperature at
Stretching of the bucket
initial measurement: °C
Bucket excavation
Bucket unloading
 5-27
December 30, 2017 5.2 Other Tests
CLG930E/936E 5.2.1 Adjustment of Valve Lash

5.2 Other Tests 3. Press down the engine timing pin and slowly
rotate the crankshaft simultaneously so as to
locate the top dead center of No.1 cylinder.
5.2.1 Adjustment of Valve Lash Insert the turning gear into the flywheel
housing and make it engage with the
flywheel gear ring. Then, rotate the engine by
1. Disconnect the support clip, hose clamp and hand or using 127-cm [1/2-in] ratchet wrench
exhaust bypass valve induction tube. or a crowbar.
Remove the crankcase ventilating pipe and
other parts which may affect removal of valve
chamber cover.

4. When the engine timing pin connects with the

hole on the camshaft gear, No. 1 cylinder is
located at the top dead center of
2. Remove the valve chamber cover. compression stroke

Cam shaft gear

Engine timing pin

Gear chamber

Be sure to disconnect the engine timing pin

after finding the top dead center to prevent it
from being damaged.
5-28
5.2 Other Tests December 30, 2017
5.2.1 Adjustment of Valve Lash CLG930E/936E

Torque value: 24 n.m [212 in-lb]

Step A
5. Intake valve lash: 0.30 mm [0.012 in].
Exhaust valve lash: 0.61 mm [0.024 in].
Check/adjust the valve when the engine is at the
cold state (the temperature is less than 60
Be sure to disconnect the engine timing pin
°C[140°F]).
to prevent it from being damaged. Mark the
shock absorber and rotate the crankshaft by
360°.

The clearance is correct if there is some

7. Adjust the valve shown in the step B.
resistance when the feeler gauge slips
between the valve rod and the rocker arm, Check the valve lash to ensure that it has no
change after tightening the rocker arm lock nut.
6. Find the top dead center of No.1 cylinder.
Check/adjust the valve (I = intake; E = exhaust)
shown in the step A.
Check the valve lash to ensure that it has no
change after tightening the rocker arm lock nut.
 5-29
December 30, 2017 5.2 Other Tests
CLG930E/936E 5.2.2 Measurement of Blow-by of Crankcase

Torque value: 24 n.m [212 in-lb] Torque value: 24 n.m [212 in-lb]

Step B

10. Install the crankcase ventilating pipe and fix it

using the support clip and hose clamp.
If the seal is not damaged, it can be reused. If
Torque value:
the seal is damaged, install new seal.
A = 24 N.m[212 in-lb].
8. Install the rubber seal into the valve chamber
cover groove. Start the installation from the B = 43 N.m [32 in-lb].
overlap part shown in the Figure. Do not
stretch the rubber seal.
If the overlap part of the seal is larger than that
shown in the Figure, adjust the length of the seal
so as to ensure that the overlap part is correct.

5.2.2 Measurement of Blow-by of

Crankcase
9. Install the O-ring on the bolt.
Install the valve chamber cover and the exhaust 1. Select correct blow-by measurement
bypass valve induction tube. maintenance tool for the engine maintained.
Determine the blow-by measurement
maintenance tool to be used by referring to
medium horse-power engine blow-by
specification sheet in this step and according
to the engine type and/or horse-power.
5-30
5.2 Other Tests December 30, 2017
5.2.2 Measurement of Blow-by of Crankcase CLG930E/936E

Pictures of blow-by tools: 3. Operate the engine with rated speed and full
load until stable values are obtained.

Part number of Size of metering hole

blow-by tool (mm) [in]
3822476 5.61 mm [0.221 in]
3822566 7.67 mm [0.302 in]
Excess engine oil overflows from the
2. Connect the water pressure gauge (the part breather pipes during the blow-by
number is ST1111-3), pressure gauge or measurement. So the engine oil volume also
sensor on the blow-by measurement directly affects the blow-by measurement
maintenance tools when measuring the blow- results.
by pressure of crankcase .

For the diesel engine running-in, if blow-by is

increased suddenly or it exceeds the
maximum limit value in any running-in steps,
it is supposed to go back to the previous step
to continue the running-in.

If the blow-by does not reach acceptable level,

interrupt the running-in and confirm the causes.
Record the blow-by measured values in steady
state.
 5-31
December 30, 2017 5.2 Other Tests
CLG930E/936E 5.2.2 Measurement of Blow-by of Crankcase

Medium horse-power engine blow-by specification sheet

New or reinstalled engine blow-by Blow-by specification for fault diagnosis
specification - mm [in] H2O and troubleshooting - mm [in] H2O
Blow-by tool Blow-by tool Blow-by tool Blow-by tool
3822476-5.61 mm 3822566-7.67 mm 3822476-5.61 mm 3822566-7.67 mm
Engine model
[0.221 in] [0.302 in] [0.221 in] [0.302 in]
measuring orifice measuring orifice measuring orifice measuring orifice
A1400 and A1700 (naturally
25.4 [1] 25.4 [1]
aspirated)
A2000 and A2300 (naturally
25.4 [1] 38.1 [1.5]
aspirated)
A2000 and A2300
38.1 [1.5] 50.8 [2]
(turbocharged)
ISF2.8 147.3 [5.8] 711.2 [28]
ISF3.8 71.1 [2.8] 254 [10]
B3.3 Tier 1, 2 50.8 [2] 101.6 [4]
B3.3, QSB3.3 Tier 3 101.6 [4] 152.04 [6]
B3.3, QSB3.3 Tier 4 Interim (less
50.8 [2] 101.6 [4]
than 74 HP)
B3.9, QSB3.9-30, B4.5, QSB4.5-
30 and B4.5s (naturally 25.4 [1] 76.2 [3]
aspirated) (less than 250 hp)
B3.9, QSB3.9-30, B4.5, QSB4.5-
30 and B4.5s (turbocharged) 101.6 [4] 431.8 [17]
(less than 250 hp)
B3.9, QSB3.9-30, B4.5, QSB4.5-
30 and B4.5s (turbocharged) 25.4 [1] 127 [5]
(more than 250 hp)
B5.9 (naturally aspirated) 50.8 [2]
s
B5.9, QSB5.9-30 and B6.7 228 .6 [9] 863.6 [34]
(less than 250 hp)
B5.9, QSB5.9-30 and B6.7s 50.8 [2] 228.6 [9]
(more than 250 hp)
ISB, ISBe, QSBe, ISDe, QSB5.9- 101.6 [4] 254 [10]
44 and ISB6.7
C8.3 101.6 [4] 254 [10]
ISC, ISCe,
QSC8.3, ISL, ISLe 304.8 [12] 304.8 [12]
and QSL9
B Gas International, B Gas Plus,
228.6 [9] 889 [35]
B LPG Plus, B5.9G, B5.9 LPG
C8.3G, C Gas Plus, L Gas Plus 203 [8] 457 [18]
5-32
5.2 Other Tests December 30, 2017
5.2.2 Measurement of Blow-by of Crankcase CLG930E/936E

Blow-by conversion chart (7.67-mm [0.302-in] measuring orifice, blow-by tool part number 3822566)

mm [in] H2O liter [cfm] / minute

25.4 [1] 50 [1.766]
50.8 [2] 84 [2.966]
76.2 [3] 103 [3.637]
101.6 [4] 119 [4.202]
127 [5] 133 [4.697]
152.4 [6] 145 [5.121]
177.8 [7] 155 [5.474]
203.2 [8] 164 [5.792]
228.6 [9] 172 [6.074]
254 [10] 180 [6.357]
279.4 [11] 187 [6.604]
304.8 [12] 193 [6.816]
330.2 [13] 200 [7.063]
355.6 [14] 206 [7.275]
381 [15] 211 [7.451]
406.4 [16] 217 [7.663]
431.8 [17] 222 [7.840]
457.2 [18] 226 [7.981]
482.6 [19] 229 [8.087]
508 [20] 235 [8.299]
533.4 [21] 239 [8.440]
558.8 [22] 242 [8.546]
584.2 [23] 246 [8.687]
 5-33
December 30, 2017 5.2 Other Tests
CLG930E/936E 5.2.3 Measurement and Adjustment of Track Tension

5.2.3 Measurement and 5. Lower the boom until the right track is raised
for about 100 ~ 200 mm from the ground to
Adjustment of Track Tension keep the track away from the ground during
operation as shown in following picture.
Measurement of the track tension

Tools and testing instrument

Steel ruler.

Machine state and parking site

1. Solid and flat parking site.

2. Maintain hydraulic oil temperature between
45°C and 55°C.
3. Set the diesel engine in the maximum speed
(turn off the A/C).
4. The pump working current is within the
normal range. 6. Rotate the track at this side backward and
5. The complete machine works in the normal forward 2 circles each with low speed idling.
mode. Taking the middle part of the track as the
inspection point, measure the distance A from
6. The working pressure and the pilot pressure the bottom of the track beam to the backside of
of the pump are within the normal range. the lower track plate according to the figure
Measurement of the track tension below.

1. Park the machine at solid and flat site.

2. Maintain the hydraulic oil temperature
between 45°C and 55°C.
3. Operate the right swing until the upper
mechanism is vertical to the lower one.
4. Operate the boom, arm and bucket until the
bucket bottom is on the ground.

Standard value of the track tension

Track type Standard value

Metal track 370-420mm
5-34
5.2 Other Tests December 30, 2017
5.2.3 Measurement and Adjustment of Track Tension CLG930E/936E

Adjustment of track tension 2. Reduce the tension

If the track tension is abnormal, adjust it 1. Loosen the filling valve 2, discharge the
according to the following steps. grease and then tighten it. As the figure
below:
1. Increase the tension

1. Fill the grease from the grease fitting 1 using

grease gun. As the figure below:

The valve may fly off as a result of the

2. To determine that the tension of the track internal high-pressure grease, so do not
shoe is normal, operate the diesel engine in loosen the filling valve 2 more than two
low idle speed and drive the machine forward circles.
for a distance which equals to the length of 2. To determine that the tension of the track
the track shoe on the ground and then stop shoe is normal, operate the diesel engine in
the machine slowly. low idle speed and drive the machine forward
3. After adjustment, measure the tension again for a distance which equals to the length of
according to the steps above to guarantee the track shoe on the ground and then stop
that the tension is normal. the machine slowly.
3. After adjustment, measure the tension again
according to the steps above to guarantee
that the tension is normal.
 5-35
December 30, 2017 5.2 Other Tests
CLG930E/936E 5.2.4 Inspection and Adjustment of Minus Feedback Pressure N1

5.2.4 Inspection and Adjustment 4. Insert the pressure gauge (6 MPa measuring
range) with pressure hoses into the pressure
of Minus Feedback Pressure N1 measurement joint (4) and measure the
pressure on the main pump feedback
Check pressure port N1.

1. Directly read the minus feedback pressure

N1 on the display. Contact Liugong service
provider if it needs to read pressure.
2. Measure the minus feedback pressure N1 on
its port shown in the figure below.

Feedback
pressure N1

Pressure test tee and

pressure test notch

Measurement steps:

1. Remove the joint group (1) from the main

pump;
2. Connect it with the main pump feedback
pressure port N1 after installing the O-ring (3)
into the pressure tee (2).
3. Install the pressure measurement joint (4)
into the pressure port of the pressure tee (2).
5-36
5.2 Other Tests December 30, 2017
5.2.5 Inspection and Adjustment of Minus Feedback Pressure N2 CLG930E/936E

Detail list 5.2.6 Release the Residual

No. Material number Name Pressure in Hydraulic Oil Lines
32C0529 Tee
1
12C2000 Shuttle valve
2 32C0617 Pressure tee
The high pressure liquid medium in the
3 12B0428 O-ring
hydraulic system and hot hydraulic medium
Pressure upon operation may cause personnel injury.
4 12C1140
measurement joint
There is still high pressure in the hydraulic
system after the diesel engine is stopped. If
5.2.5 Inspection and Adjustment the pressure is not released before
of Minus Feedback Pressure N2 maintaining any hydraulic system, serious
personal injury may be caused. Be sure that
all the accessories have been put on the
Method I: Directly read the minus feedback ground, and the hydraulic oil has been
pressure N2 on the display. Contact Liugong cooled before removing any components or
service provider if it needs to read pressure. lines. The oil filler cap can be removed only
Method II: Measure the minus feedback pressure when the diesel engine has been stopped,
N2 on its port shown in the figure below. and the oil filler cap has been cooled enough
that can be touched by hands.

Release the pressure of the hydraulic system

Feedback according to the following steps:
pressure N2
1. Park the excavator on the flat ground.
2. Completely place the work implement on the
horizontal ground. Make the bucket in
complete contact with the ground, as shown
in the figure below:

The measurement steps are same with that of

N1
 5-37
December 30, 2017 5.2 Other Tests
CLG930E/936E 5.2.6 Release the Residual Pressure in Hydraulic Oil Lines

3. Stop the diesel engine.

4. Turn the diesel engine starting switch to "ON"
position, but do not start the diesel engine.
5. Turn the pilot cut-off lever to "ON" position.
6. Repeatedly turn the pilot lever or foot pilot
valve to the maximum angle, release high
pressure oil in corresponding lines, and
meanwhile, release pressure in
corresponding pilot lines.
7. Turn the pilot cutoff lever to "OFF" position.
8. After the pressure is released from the line,
turn the pilot cut-off lever to "OFF" position
9. Turn the diesel engine starting switch to
"OFF" position.
10. Turn the diesel engine starting switch to "ON"
position to start the diesel engine, operate it
at low idle speed for about 10 seconds for
storing pressure into the accumulator, and
then stop the diesel engine.
11. Repeat the steps 3-10 above for several
times.
12. Screw out the exhaust valve protective caps
of an air filter above the hydraulic oil tank,
then press the exhaust valve and release air
pressure in the hydraulic oil tank until the gas
with pressure is fully released.
13. Tighten the exhaust valve protective caps on
the air filter.
14. When the pressure in the hydraulic system
pipeline has been released, the
corresponding lines or components can be
removed.

Although the pressure in pipelines is

released to the most extent by the above
steps, a minority of pressure still cannot be
released fully. When removing the line
connections such as fittings, necessary
protections shall be prepared to avoid
personnel injury.
)
5-38
5.2 Other Tests December 30, 2017
5.2.7 Exhaust of Various Devices CLG930E/936E

5.2.7 Exhaust of Various Devices

Exhaust shall be carried out upon the following repairs:

Exhaust project

Steps

Job content Hydraulic Start the Oil   

pump diesel cylinder motor motor  
exhaust  exhaust exhaust exhaust

  
  
 


  
 

element
  

hydraulic pump
 


  



  
  

   

  


 


  



 


pipeline
 5-39
December 30, 2017 5.2 Other Tests
CLG930E/936E 5.2.7 Exhaust of Various Devices

Exhaust the air in the pump 3. Loosen the exhaustion plug and check for oil
outflow.
When maintaining the main pump or replacing
the hydraulic oil lines, exhaust the air according 4. If no oil outflow, fill the hydraulic oil to the
to the methods below: pump housing body.
5. Make the diesel engine run at idle. If there is
no bubble any more, tighten the exhaustion
plug and the exhaust is over.
The hydraulic oil pressure and the hot oil
may cause personal injury.
When the diesel engine is stopped, the
hydraulic oil can still be in the hydraulic If the pump runs without full oil in the pump
system. If the pressure is not released before body, the abnormal heat may be produced
maintaining any hydraulic system, serious resulting in the early damage for the pump.
personal injury may be caused.
Exhaust the air in the cylinder
Be sure that all the accessories are put on the
ground, and the oil has been cooled before 1. Start the diesel engine and operate it for 5min
removing any components or lines. with low idling.
2. Operate the diesel engine in low speed and
The oil filler cap can be removed only when
telescope the cylinder to the position about
the diesel engine has been stopped, and the
100 mm away from the stroke end for 4-5
oil filler cap has been cooled enough that can
times.
be touched by hands.

Do not telescope the cylinder to the stroke

end, or. The piston seal will be damaged by
the air in the cylinder.

3. Operate the cylinders to the stroke end for 3-

4 times.
4. Operate the cylinders to the stroke end for 4-
5 times to exhaust the air completely.

1. Exhaustion plug
1. Park the machine on the flat ground, lower
the bucket to the ground and pull the pilot
control level to the locked position.
2. Shut down the diesel engine and take the key
out.
5-40
5.2 Other Tests December 30, 2017
5.2.7 Exhaust of Various Devices CLG930E/936E

Exhaust the air in the travel motor 3. Operate the diesel engine in low speed and
swing the work implement by 90° to make it
locate in the side of the track.

The air can be exhausted only after the

hydraulic oil in the travel motor housing was
drained.

1. Before starting the diesel engine, remove the

oil drain hose on the travel motor housing, fill
the hydraulic oil to the motor housing until the
level reaches the discharge port, and then
connect the oil drain hose.

4. Jack up the machine with the work implement

to make the track slightly off the ground, and
operate the track in no-load condition for 2
min.
5. Repeat the operation above in the left and
right side. And rotate the track forward and
backward evenly.

Exhaust the air in the accessories (if any)

1. If the knapper or other accessories are

1. Oil drain hose equipped, make the diesel engine run in low
2. Operate the diesel engine in low idle speed, speed, and repeatedly operate the auxiliary
unscrew the nuts of oil drain hose connector pedal (1) for about 10 times until the air is
on the motor housing, and tighten the nuts exhausted from the oil line of the
when the hydraulic oil outflows. accessories.

1. Auxiliary pedal
 5-41
December 30, 2017 5.2 Other Tests
CLG930E/936E 5.2.8 Inspection of Diode

5.2.8 Inspection of Diode

The diode, also called crystal diode, is electronic

device capable of unidirectional conduction
If manufacturer specifies the exhaust current. There is one PN joint and two lead
method, exhaust should be performed terminals in the semiconductor diode. According
according to the specified method. to the direction of the applied voltage, the
electronic device, which is popular, has the
2. After exhausting the air, turn off the diesel
transduction performance of the unidirectional
engine and leave the machine alone for 5
current.
minutes to eliminate the bubble in the
hydraulic cylinder.
3. After exhausting the air, check the oil level,
and refill in case of low level.

1. Measure the diode with the diode position on

a digital multimeter:
(1) Connect the red probe (+) to the positive pole
(P) of the diode while the black probe (-) to
the negative pole (N) of the diode, and then
the diode is in positive biased. If the diode is
normal, the multimeter will displays a certain
value.
5-42
5.2 Other Tests December 30, 2017
5.2.9 Adjustment of Compressor Belt Tensioner CLG930E/936E

(2) Connect the red probe (+) to the negative 5.2.9 Adjustment of Compressor
pole (N) of the diode, and the black probe (-)
to the positive pole (P) of the diode, then the
Belt Tensioner
diode is in negative biased. If the diode is
normal, the multimeter will display 0L or a
very large value.
(3) During the measurement, if the values
Before inspection, move the machine to the
measured for two times are very small, it
level ground, and lower the work implement
indicates a short circuit in the diode; if the
to the ground and turn off the diesel engine.
values measured for two times are very large
or shows 0L, there is an open circuit in the
diode. Check
2. Use the Ohm grade of the digital multimeter
1. Open the engine hood, remove the left and
to measure the diode:
right fan shields above the compressor.
(1) Connect the red probe (+) to the positive pole
2. Press the middle parts of the belt between
(P) of the diode while the black probe (-) to
the diesel engine pulley and compressor
the negative pole (N) of the diode, and then
pulley to measure the flexibility (f) of the belt.
the diode is in positive biased. Read out the
When the pressure is Wd = 58.5N (about 6
measured resistance value.
kg), the produced flexibility of the belt shall
(2) Connect the red probe (+) to the negative be f = 5~8 mm.
pole (N) of the diode while the black probe (-)
to the positive pole (P) of the diode, and then
the diode is in reverse biased and read the
measured resistance value.
(3) If the two measured resistance values are
quite different, it indicates that the
performance of the diode is good; otherwise,
it indicates that the performance of the diode
is poor or the diode is damaged -- internal
short or open circuit.
 5-43
December 30, 2017 5.2 Other Tests
CLG930E/936E 5.2.10 Performance Test of Travel Motors and Reduction Gears

Adjustment 5.2.10 Performance Test of Travel

If the belt flexibility is abnormal, perform Motors and Reduction Gears
adjustments according to the following
procedures. Carry out the following performance tests upon
1. Unscrew the tension pulley locknut (1); disassembly and maintenance of travel motors
and reduction gears.
2. Clockwise screw the bolt (2) to adjust the A/C
belt tension. Test method: measure the pressures of following
test points: left side motors a1, a2, T1; right side
3. Adjust the tension pulley (3) to an motors: a1, a2, T1.
appropriate position, and fasten the tension
pulley locknut (1).
Pressure measurement side

Left side
3

1
Right side

Notice:
(1) If the belt cannot be tensed due to excessive
stretches, or found scratches and cracks,
replace with a new belt timely.
(2) If the belt is replaced, re-adjust the tension of
the belt after the machine works for 1 hour.
(3) After the bolt is tightened, check the tension
of the belt according to the methods above.
4. Reinstall the removed components upon the
completion of belt flexibility measurement.

Test conditions:
1. Air is not allowed in the lines
2. Hydraulic oil temperature is approx 50±5°C.
5-44
5.2 Other Tests December 30, 2017
5.2.10 Performance Test of Travel Motors and Reduction Gears CLG930E/936E

Test items and standard values:

Operation status
Test
No. Contents Operation Gears Criteria
Horizontal Vertical ground
direction direction

About 4 seconds
Left and right pumping
pressure difference < 3
Low MPa, without dragging
Oil drainage <0.2 MPa,
Flat walking Max < 0.69 MPa
1
and stop Left and right pumping
About 4 seconds
pressure difference < 3
High MPa, without dragging
Oil drainage <0.2 MPa,
Max < 0.69 MPa

Slowly About 15 seconds Low Curve is flat, without

operate dragging
2
forward → Oil drainage <0.2 MPa,
back High Max < 0.69 MPa

About 3 seconds
Atmospheric pressure
<34.3MPa,
Unilateral
3 High Max<34.3MPa
drive
Oil drainage Max < 0.69
MPa

About 3 seconds Atmospheric pressure

Concrete <34.3MPa,
Unmovable
4 High Max<34.3MP
rotation
Oil drainage Max < 0.69
MPa
About 0.3 seconds Left and right pumping
pressure difference < 3
MPa,
Rapid
Left and right pumping
5 alternate High
pressure Max < 34.3
(forward)
MPa
Oil drainage Max < 0.69
MPa

Go forward
Synchronous switching,
by switching
Low without dragging
6 between high
High Oil drainage <0.2 MPa,
and low
Max < 0.69 MPa
velocity

About 3 seconds
Go forward
and
7 Low
backward
slope
 6-1
December 30, 2017 Fault Diagnosis
CLG930E/936E

Fault Diagnosis

6.1 Precautions for Fault Diagnosis ..............................................................................6-5

6.2 Basic Fault Detection before Maintenance .............................................................6-6
6.3 Classification of Faults .............................................................................................6-9
6.4 Fault Code ................................................................................................................6-11
6.4.1 DTC 101001 Extremely Low Battery Voltage..............................................................................6-11
6.4.2 DTC 101001 High Battery Voltage..............................................................................................6-17
6.4.3 DTC 101017 Low Battery Voltage ..............................................................................................6-21
6.4.4 DTC 111001 System Charging Fault ..........................................................................................6-27
6.4.5 DTC 121015 Oil Pressure Switch Disconnected.........................................................................6-30
6.4.6 DTC 121018 Low Oil Pressure ...................................................................................................6-33
6.4.7 DTC 121305 Hand Pilot Pressure Switch Disconnected ............................................................6-35
6.4.8 DTC 121405 Foot Pilot Pressure Switch Disconnected..............................................................6-39
6.4.9 DTC 121604 Air Filter Switch Shorted to Ground .......................................................................6-43
6.4.10 DTC 121615 Air Filter Clogging ................................................................................................6-46
6.4.11 DTC 131000 High Engine Speed..............................................................................................6-48
6.4.12 DTC 131100 Extremely High Coolant Temperature .................................................................6-51
6.4.13 DTC 131103 Coolant Temperature Sensor Voltage Above the Range Value ..........................6-53
6.4.14 DTC 131104 Coolant Temperature Sensor Voltage Below the Range Value...........................6-56
6.4.15 DTC 131115 High Coolant Temperature ..................................................................................6-59
6.4.16 DTC 131116 High Coolant Temperature ..................................................................................6-61
6.4.17 DTC 131200 Extremely High Hydraulic Oil Temperature .........................................................6-63
6.4.18 DTC 131203 Hydraulic oil Temperature Sensor Voltage Above the Range Value ..................6-65
6.4.19 DTC 131204 Hydraulic Oil Temperature Sensor Voltage Below the Range Value ..................6-68
6.4.20 DTC 131215 High Hydraulic Oil Temperature ..........................................................................6-71
6.4.21 DTC 131216 Extremely High Hydraulic Oil Temperature .........................................................6-73
6.4.22 DTC 131303 Fuel Level Sensor Voltage Above the Range Value ...........................................6-75
6.4.23 DTC 131304 Fuel Level Sensor Shorted to Ground ................................................................6-80
6.4.24 DTC 131317 Low fuel level ......................................................................................................6-85
6.4.25 DTC 131603 Water-in-Fuel Sensor Voltage Above the Range Value .....................................6-88
6.4.26 DTC 131604 Water-in-Fuel Sensor Voltage Below the Range Value.......................................6-91
6.4.27 DTC 131605 Water-in-fuel Sensor Open-circuit ......................................................................6-94
6.4.28 DTC 131615 Water-in-fuel .......................................................................................................6-97
6-2
Fault Diagnosis December 30, 2017
CLG930E/936E

6.4.29 DTC 131703 Sensor Power (5V) Shorted to the Battery .........................................................6-99
6.4.30 DTC 131704 Sensor Power (5V) Shorted to the Ground .......................................................6-102
6.4.31 DTC 141105 Pump Proportional Solenoid Valve Feedback Open-Circuited .........................6-106
6.4.32 DTC 141006 Pump Proportional Solenoid Valve Feedback Overcurrent ..............................6-109
6.4.33 DTC 141104 Pump Proportional Solenoid Valve Shorted to Ground ....................................6-112
6.4.34 DTC 141105 Pump Proportional Solenoid Valve Feedback Open-circuited ..........................6-115
6.4.35 DTC 151004 Attachment Confluence Solenoid Valve Shorted to Ground .............................6-118
6.4.36 DTC 151005 Attachment Confluent Solenoid Valve Open-circuited or Shorted to
the Battery ..........................................................................................................................................6-121
6.4.37 DTC 151204 A2 Travel Speed Solenoid Shorted to Ground ..................................................6-124
6.4.38 DTC 151205 A2 Travel Shift Solenoid Valve Open-Circuited or Shorted to the Battery.........6-127
6.4.39 DTC 151304 A3 Flattening Solenoid Valve Shorted to Ground ..............................................6-131
6.4.40 Fault Code 151305 A3 Flattening Solenoid Valve Open-Circuited or Shorted to the Battery .6-134
6.4.41 DTC 151404 A8 Trenching Solenoid Valve Shorted to the Ground........................................6-138
6.4.42 DTC 151405 A8 Trenching Solenoid Valve Open-Circuited or Shorted to the Battery ...........6-141
6.4.43 DTC 151504 A5 Flow Adjusting Solenoid Shorted to Ground ................................................6-145
6.4.44 DTC 151505 A5 Flow Adjusting Solenoid Valve Open-Circuited or Shorted to the Battery....6-148
6.4.45 DTC 151605 A6 Flow Adjusting Solenoid Open-circuited or Shorted to the Battery ..............6-152
6.4.46 DTC 151704 A7 Power Boosting Solenoid Valve Shorted to the Ground ..............................6-156
6.4.48 DTC 151705 A7 Power Boosting Solenoid Valve Open-Circuited or Shorted to the Battery..6-159
6.4.49 DTC 151804 A4 Travel Lifting Solenoid Valve Shorted to the Ground ..................................6-163
6.4.50 DTC 151805 A4 Travel Lifting Solenoid Valve Open-Circuited or Shorted to the Battery ......6-166
6.4.50 DTC 151905 A5 or A6 Solenoid Valve Feedback Open-Circuited .........................................6-170
6.4.51 DTC 151906 A5 or A6 Solenoid Valve Feedback Overcurrent ..............................................6-173
6.4.52 DTC 171004 SHORT CIRCUIT TO GROUND OF BATTERY RELAY ..................................6-176
6.4.53 DTC 171104 Auto Preheating Relay Shorted to the Ground ..................................................6-179
6.4.54 DTC 171105 Auto Preheating Relay Open-Circuited or Shorted to the Battery .....................6-182
6.4.55 DTC 171204 Start Cut-off Relay Shorted to Ground ..............................................................6-185
6.4.56 DTC 171205 Start cut-off Output Open-circuited or Shorted to the Battery ...........................6-188
6.4.57 DTC 201004 Travel Alarm Shorted to Ground .......................................................................6-191
6.4.58 DTC 211003 P1 Pump Pressure Sensor Voltage Above the Range Value ...........................6-194
6.4.59 DTC 211004 P1 Pump Pressure Sensor Voltage Below the Range Value ...........................6-197
6.4.60 DTC 211003 P2 Pump Pressure Sensor Voltage above the Range Value ...........................6-200
6.4.61 DTC 211104 P2 Pump Pressure Sensor Voltage below the Range Value ............................6-203
6.4.62 DTC 211203 N1 Negative Flow Pressure Sensor Voltage Above the Range Value .............6-206
6.4.63 DTC 211204 N1 Negative Flow Pressure Sensor Voltage Below the Range Value ..............6-209
 6-3
December 30, 2017 Fault Diagnosis
CLG930E/936E

6.4.64 DTC 211303 N2 Negative Flow Pressure Sensor Voltage Above the Range Value .............6-212
6.4.65 DTC 211304 N2 Negative Flow Pressure Sensor Voltage Below the Range Value ..............6-215
6.4.66 DTC 221001 Actuator Feedback Voltage below the Range Value ........................................6-218
6.4.67 DTC 221003 Actuator Feedback Voltage Above the Range Value .......................................6-222
6.4.68 DTC 221007 Actuator Getting Stuck ......................................................................................6-226
6.4.69 DTC 221013 Actuator outside the Calibrated Range .............................................................6-229
6.4.70 DTC 221104 Actuator AC1 Shorted to Ground ......................................................................6-234
6.4.71 DTC 221204 Actuator AC2 Shorted to Ground ......................................................................6-237
6.4.72 DTC 221305 Actuator AC1 Open-Circuited ...........................................................................6-240
6.4.73 DTC 221306 Actuator AC1 Overcurrent ................................................................................6-243
6.4.74 DTC 221405 Actuator AC2 Terminal Open-Circuited ............................................................6-246
6.4.75 DTC 221406 Actuator AC2 Overcurrent ................................................................................6-249
6.4.76 DTC 231012 Abnormal Controller Heartbeat .........................................................................6-252
6.4.77 DTC 231014 CAN Bus Communication Error ........................................................................6-254
6.4.78 DTC 241014 Accelerator Knob outside the Measurement Range ..........................................6-256
6.4.79 DTC 251004 Fuel Pump Relay Shorted to Ground.................................................................6-259
6.4.80 DTC 251005 Fuel Pump Relay Open-Circuited or Shorted to the Battery..............................6-263
6.4.81 DTC 261011 GPS Antenna Fault............................................................................................6-267
6.4.82 DTC 261111 GPS Module Fault .............................................................................................6-269
6.4.83 DTC 261211 GSM Signal Fault ..............................................................................................6-270
6.4.84 DTC 261311 GPRS Connection Fault ....................................................................................6-271
6.4.85 DTC 261411 SIM Card Read Fault .........................................................................................6-272
6.4.86 DTC 261512 Abnormal GPS Heartbeat ..................................................................................6-273
6.4.87 DTC 261611 Automatic Locking Level 1 Abnormal GPS Heartbeat, the Machine is
Limited for Use ...................................................................................................................................6-276
6.4.88 DTC 261614 Forced Locking Level 1 Payment Expired, the Machine is Limited for Use.......6-279
6.4.89 DTC 261711 Automatic Locking Level 2 Abnormal GPS Heartbeat, and the Machine is Prohibited
for Use ...............................................................................................................................................6-280
6.4.90 DTC 261714 Forced Locking Level 2 Overdue Payment, and the Machine is Prohibited for
Use ....................................................................................................................................................6-283
6.4.91 DTC 261814 Please Pay the Due Loan on Time ....................................................................6-283

6.5 Fault Diagnosis of Electrical System...................................................................6-284

6.5.1 Troubleshooting Solution for E1-Battery Power Loss ...............................................................6-284
6.5.2 E2 Abnormal Battery .................................................................................................................6-286
6.5.3 E3 Automatic Slowdown Failed ................................................................................................6-289
6.5.4 E4 Engine cannot be Started ....................................................................................................6-292
6-4
Fault Diagnosis December 30, 2017
CLG930E/936E

6.5.5 E5 Preheater does not Work.....................................................................................................6-304

6.5.6 E8 All the Work Implements, Revolving and Traveling cannot Move........................................6-310
6.5.7 E9 Display Panel Showing Nothing ..........................................................................................6-315
6.5.8 E8- Incorrectly Displayed Hydraulic Oil Temperature ...............................................................6-319
6.5.9 E11 Fuel Gauge cannot Display correctly.................................................................................6-322
6.5.10 E10 Windshield Wiper out of Work .........................................................................................6-327
6.5.11 E13 Backup Alarm unable to Sound .......................................................................................6-332
6.5.12 E14 A/C Panel unable to Display ............................................................................................6-335
6.5.13 E13 A/C no Wind or Abnormal Air Volume .............................................................................6-340
6.5.14 E16 Poor A/C Refrigeration ....................................................................................................6-342
6.5.15 E15 Air Conditioning Abnormal Alarm E11--Inner Gas Sensor Break Line ............................6-345
6.5.16 E18 Air Conditioning Abnormal Alarm E12--Inner Gas Sensor Short Circuit..........................6-347
6.5.17 E17 Air Conditioning Abnormal Alarm E17--Water Temperature Sensor Break Line .............6-349
6.5.18 E18 Air Conditioning Abnormal Alarm E16--Water Temperature Sensor Short Circuit ..........6-351
6.5.19 E19 Air Conditioning Abnormal Alarm E18--Solar Sensor Short Circuit .................................6-353
6.5.20 E20 Air Conditioning Abnormal Alarm E43--Air Blowing Valve Abnormal ..............................6-355
6.5.21 E21 Abnormal Alarm of the A/C E44 – Abnormal Air Mixing Door..........................................6-357

6.6 Fault Diagnosis of the Hydraulic System and Mechanical System ..................6-359
6.6.1 System Table of the Hydraulic System and Mechanical System ..............................................6-359
6.6.2 Excessive Barking Angle for H1 Slewing Stop..........................................................................6-360
6.6.3 Abnormal Noise from H2 Pump Mounting Position...................................................................6-361
6.6.4 H3 Start the Engine, and All Operations have no Response ....................................................6-362
6.6.5 H4 Hydraulic Oil Emulsification, ...............................................................................................6-363
6.6.6 H5 Abnormal Hydraulic Oil Temperature Rise ..........................................................................6-364
6.6.7 H6 Slewing abnormally to Left and Right Directions .................................................................6-365
6.6.8 H7 No Response for Slewing Single Direction Operation .........................................................6-366
6.6.9 H8 Swing cannot be Stopped ...................................................................................................6-367
6.6.10 H9 Fail to Actuate Unilateral Travel Mechanism .....................................................................6-368
6.6.11 H10 Travel Deviation ..............................................................................................................6-369
6.6.12 H11 Slow Speed of the Boom, Arm or Bucket ........................................................................6-370
6.6.13 H12 Weak Actions of the Boom, Arm or Bucket .....................................................................6-371
6.6.14 H13 Significantly Reduced Engine Speed or Engine Stalling .................................................6-372
 6-3
December 30, 2017 6.1 Precautions for Fault Diagnosis
CLG930E/936E

6.1 Precautions for Fault Diagnosis

● Park the machine on the flat ground, check whether the locking pin, block and parking brake are
fixed firmly.
● When two or more workers operate the machine, follow the agreed signal strictly, and any
unauthorized people are not allowed to get close to the machine.
● If the radiator cover is removed when the engine is still hot, the hot coolant may spray out which will
cause scald. Therefore, start the fault diagnosis when the engine is cooled.
● Specially notice that do not touch any hot components or avoid being jammed by any rotating
components.
● When disconnecting the wire, be sure to disconnect the negative pole (-) of the battery firstly.
Be sure to release the inner pressure first when removing the plug or cover where the oil pressure, water
pressure or air pressure may exist. When installing the measuring device, make sure that it is connected
correctly.
6-4
6.2 Basic Fault Detection before Maintenance December 30, 2017
CLG930E/936E

6.2 Basic Fault Detection before Maintenance

Do the following tests before having your authorized LiuGong dealer repair your machine or when your
machine is not functioning properly. Doing these tests can help the maintenance personnel to repair your
machine as soon as possible.

Do the following tests when the engine is running and shuts down, respectively.
If the machine runs in a closed space, be sure to discharge the exhaust gases before starting the
engine for maintenance of the machine.
No irrelevant personnel is allowed to be close to the machine working and detection area.
Some tests may be required to be done when the machine is traveling. Therefore, before starting
any test, make sure the driver has been trained specially and has been qualified.

Some tests may require the appropriate hearing protection devices.

Some tests may need the help of the specialized testing tools. Therefore, before starting any test, make
sure the operators understand these tools fully.
Before performing any of the following tests, make sure all routine examination items have been
completed.
Start the engine and do the testing by following the relevant guidance steps. When detecting the
hydraulic system components, make sure that the hydraulic system has been fully heated and all
hydraulic components have reached normal operating temperature.

No. Test items Test requirements

1 Turn the start switch to "ON" position, but do not start the engine.
 6-5
December 30, 2017 6.2 Basic Fault Detection before Maintenance
CLG930E/936E

No. Test items Test requirements

Hydraulic oil state

Shut down the engine, park
the machine on a firm and 1. Check whether the oil level is within the normal range.
level ground, and make the Notice: Check before the engine is started.
machine in the hydraulic oil 2. Check whether the oil level is between the MIN and MAX scales of the
2 testing state (the arm is dipstick.
stretched completely, the 3. Check whether the cold hydraulic oil level is between the MIN and MAX
bucket is retracted, and the scales of the dipstick.
work attachment is lowered to
ground). 4. Check the hydraulic oil lines or the connectors for damage or leakage.
5. Visually check the machine for wear or damage sign. Whether the parts are
damaged or lost. Whether the welding piece has cracks.
6. Check whether any parts are lost.

7. Check whether the track has obvious scratches or wear.

Horn Check whether the horn sounds. (Yes or No)

Wiper Check whether the front wiper works normally. (Yes or No)

Fan Check whether the internal circulation fan works. (Yes or No)
Lighting equipment (work light,
3 revolving signal light, brake Check whether the outdoor light and dome light work normally.
light, dome light, etc.)
Instrument, meter and Check whether all the indicators come on.
indicator If not, do not start the engine.
Operate all the switches and control units to check whether they can work
Switches and control units normally.
If not, do not start the engine.
Cab Check whether all the control levers are in the correct positions.

Safety warning label Check whether the safety warning labels on the machine can be seen clearly.
4 Check whether the cab windows and doors can be opened smoothly. Whether
Door lock and engine hood the door lock can be locked or not.
lock Check whether the engine hood can be closed. Whether the engine hood can
be locked.
6-6
6.2 Basic Fault Detection before Maintenance December 30, 2017
CLG930E/936E

No. Test items Test requirements

Check the surrounding of the engine for obvious damage or oil leakage sign.

Start the engine and listen to the engine for abnormal noise.

When the engine runs at idle, whether the oil pressure indicator goes out.

5 Engine system Check whether the engine speed is normal. Whether the operation is smooth.
After the engine runs for a period, check whether the engine temperature is
within the normal working range.
After the engine is preheated and started, observe whether the exhaust gas is
discharged. If any, what is color of the exhaust gas? Grayish white, white or
black?
Check whether the engine working temperature is within the normal range.
6 Engine runs at idle speed After the engine runs at idle for several minutes, check whether the A/C
refrigerates.
Start the engine and check the battery voltage on the display to guarantee that
7 Charging of battery
the voltage is not less than 24V.
 6-7
December 30, 2017 6.3 Classification of Faults
CLG930E/936E

6.3 Classification of Faults

In this chapter, the faults are divided into three categories

1. DTC

If the machine display shows DTC, perform the fault diagnosis corresponding to the code according to
the displayed DTCs

2. Electrical system faults (for E series)

In the Electrical System Faults, the typical electrical faults are introduced. The location drawing for main
faulted parts, relevant circuit diagram and the detailed diagnosis procedures are equipped.
The faults introduced in this chapter are shown in the following table

Fault SN Fault symptom Consequence

E1 Battery power loss The battery is damaged.
E2 The battery is abnormal The battery is damaged.
E3 Automatic slowdown fails Increased fuel consumption and noise
Engine cannot be started (the engine does not
E4 Fail to work.
rotate)
E5 Engine shuts down during operation System fault.
All the work implements, revolving system and
E6 No action and fails to work.
travel system fail to move
E7 Display panel shows nothing It can not display the machine information.
Reducing the pump current and engine speed can
affect the working performance of the complete
E8 Incorrect display of hydraulic oil temperature
machine, or cause damage to the engine and
hydraulic components
The fuel level display is inaccurate, which brings
E9 Fuel gauge cannot display correctly
trouble to the work.
Foreign matters on glass cannot be removed; the
E10 Windshield wiper does not work
sight for operator is poor.
Alarm system is faulty, causing potential safety
E11 Travel alarm does not sound
hazard.
E12 A/C panel displays nothing Air conditioning system cannot work
E13 A/C blows no air or air volume is abnormal The service effect of A/C is poor
E14 Poor A/C refrigeration Poor refrigerating effect of air conditioning system
Abnormal A/C alarm E11 -- Internal air sensor
E15 The service effect of A/C is poor
open circuit
Abnormal A/C alarm E12 -- Internal air sensor
E16 The service effect of A/C is poor
short circuit
Abnormal A/C alarm E15 -- Water temperature
E17 The service effect of A/C is poor
sensor open circuit
Abnormal A/C alarm E16 -- Water temperature
E18 The service effect of A/C is poor
sensor short circuit
6-8
6.3 Classification of Faults December 30, 2017
CLG930E/936E

Fault SN Fault symptom Consequence

Abnormal A/C alarm E18 -- solar sensor short
E19 The service effect of A/C is poor
circuit
Abnormal A/C alarm E43 -- Air blowing valve
E20 The service effect of A/C is poor
abnormal
Abnormal A/C alarm E44 -- Air mixing valve
E21 The service effect of A/C is poor
abnormal

3. Faults of hydraulic mechanical system (for H series)

The Faults of Hydraulic System and Mechanical System mainly introduce the diagnosis methods for the
common faults in the hydraulic system.
The faults introduced in this chapter are shown in the following table

No. Fault symptom

H1 Excessive braking angle for slewing stop
H2 Abnormal noise from pump mounting position
H3 When the engine is started, all operations are unresponsive
H4 Hydraulic oil emulsification
H5 Abnormal hydraulic oil temperature rise
H6 Normal slewing cannot be achieved either in the left direction or in the right direction
H7 Unidirectional slewing operation is unresponsive
H8 Rotation cannot be stopped
H9 Unilateral travel mechanism fails to move completely
H10 Travel deviation
H11 Boom, arm or bucket moves slowly
H12 Weak actions of the boom, arm or bucket
H13 Significantly reduced engine speed or engine stalling
 6-9
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.1 DTC 101001 Extremely Low Battery Voltage

6.4 Fault Code System description

When the alternator does not work or generates

6.4.1 DTC 101001 Extremely Low a low voltage, the battery supplies power to the
electrical equipment. When the engine starts, the
Battery Voltage battery supplies power to the starter motor. After
the machine is started, the battery is charged by
DTC Description Consequence the alternator. When the electrical equipment
needs more power simultaneously and the
Extremely low battery alternator is overloaded, the battery assists the
voltage (The controller
It is difficult to alternator to supply power. The battery has a
101001 detects the battery
voltage is extremely low
start the engine. rated voltage of 12V. The complete machine is
- below 16V.) powered by two batteries in series.
6-10
6.4 Fault Code December 30, 2017
6.4.1 DTC 101001 Extremely Low Battery Voltage CLG930E/936E

Component location

Front

Battery

Attached drawing

Alternator

Start motor
 6-11
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.1 DTC 101001 Extremely Low Battery Voltage

Fault diagnosis and troubleshooting steps

Step 1 Check the battery terminals for looseness or rust

Notice: Be sure to turn off the electric lock before checking whether the battery cables are
secured reliably.
Inspection method
Turn the battery terminals by hand or with the tools, and check them for looseness;
Visually check the terminals for rust.
Whether the battery terminals become loose or rusty?
YES NO
Tighten or derust
Go to Step 6 Go to Step 2
Step 2 Check whether the battery voltage is too low

Notice: Make sure the ignition switch is at the OFF position before assembling and
removing the battery cables. When assembling, install the positive terminals before the
negative terminals. Removal is the reverse of installation. This can avoid damage to the battery
terminals and the wrench due to short-circuit spark.
Notice: During the detection period, turn the start key switch to the OFF position
6-12
6.4 Fault Code December 30, 2017
6.4.1 DTC 101001 Extremely Low Battery Voltage CLG930E/936E

Inspection method
Low battery voltage may caused by the three reasons: 1. Battery is not charged for a long time; 2
Battery is broken; 3. Feeding.
Check the battery in the following procedures:
1. Check the battery hydrometer. If the hydrometer becomes black, the battery needs to be charged. If
the hydrometer becomes white, the battery has been damaged. If the hydrometer is in the green
status, the battery is good.
2. Measure the battery voltage with the multimeter: Turn the multimeter to its DC voltage function
(200V), and connect the red probe to the positive battery terminal and the black probe to the
negative battery terminal. The schematic diagram for detection is as follows:

Black probe
Red probe

Is the battery voltage too low?

YES NO
Charge or replace the battery
Go to Step 6 Go to Step 3
Step 3 Check the charging harness for open-circuit (check whether the coupling ends become loose)

Notice: Pay special attention to the following when conduct the measurement with the
engine running: 1. Being scalded by overheated engine block. 2. Prevent the harnesses,
clothing and others from being drawn into the belts and the flywheel. 3. It is prohibited for the
complete machine to actuate.
Notice: Properly pack up the harness and leads: prevent the harness from being folded and
bent forcedly. It shall be kept away from moving components as far as possible to prevent
tensile failure and wear. Avoid friction with sharp metal edges. Keep away from oil and water as
far as possible. Keep away from high temperature parts (e.g. engine block) as far as possible.
 6-13
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.1 DTC 101001 Extremely Low Battery Voltage

Inspection method
1. Check the battery charging harness (# 120) for wear and its terminals for looseness
2. Check the charging harness for open-circuit with the multimeter: Method A: Turn the start key
switch to the OFF position. Turn the multimeter to its resistance function (200Ω), and measure the
resistance of the battery charging harness (# 120) (normally, <10Ω). For the alternator location and
the starter motor location, see the attached drawing

Start motor Alternator

Connect the multimeter probes to both ends

of the charging harness

Method B: Turn the start key switch to the ON position and turn the multimeter to its voltage function,
and then measure the voltage between the alternator terminal B and the grounding (normally, the
battery voltage about 25V).

Connect the red probe to Connect the black

the generator B+ probe to ground

Whether the charging harness is open-circuit or not (the coupling ends become loose)?
YES NO
Repair the harness or re-connect it
Go to Step 6 Go to Step 4
6-14
6.4 Fault Code December 30, 2017
6.4.1 DTC 101001 Extremely Low Battery Voltage CLG930E/936E

Step 4 Check whether the alternator fails or the output voltage is low

Notice: Pay special attention to the following when conduct the measurement with the
engine running: 1. Being scalded by overheated engine block. 2. Prevent the harnesses,
clothing and others from being drawn into the belts and the flywheel. 3. It is prohibited for the
complete machine to actuate.
Inspection method
After the complete machine is started, there are two possible causes for the alternator fault:
1. The belt is too loose.
2. Is there a fault in the alternator?
Check the battery in the following procedures:
1. Stop the engine and check whether the alternator belt becomes loose.
2. Start the engine, and measure the voltage between the alternator terminal B and the grounding with
the multimeter (normally, higher than the battery voltage)
Whether the alternator fails or its output voltage is low?
YES NO
1. Tighten or replace the drive belt
2. Contact local LiuGong dealer or authorized
service center.
Go to Step 6 Go to Step 5

Step 5 Check whether the controller power voltage is too low

Notice: Turn the start key switch to the ON position

Inspection method
1. Check the controller power line for wear and the coupling ends for looseness
2. Turn the multimeter to its DC voltage function (200V), and measure the voltage between the
controller power terminal (J1-2, J1-3, J1-4, J1-5, J1-6) and the grounding, respectively.
Whether the controller power voltage is too low?
YES NO
Repair the harness or re-connect it
Go to Step 6 Go to Step 6

Step 6 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-15
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.2 DTC 101001 High Battery Voltage

6.4.2 DTC 101001 High Battery System description

Voltage When the alternator does not work or generates
a low voltage, the battery supplies power to the
electrical equipment. When the engine starts, the
DTC Description Consequence
battery supplies power to the starter motor. After
High battery voltage (the the machine is started, the battery is charged by
battery voltage detected the alternator. When the electrical equipment
The engine may
101003 by the controller is
shut down needs more power simultaneously and the
extremely high (higher
than 30V).) alternator is overloaded, the battery assists the
alternator to supply power. The battery has a
rated voltage of 12V. The complete machine is
powered by two batteries in series.
6-16
6.4 Fault Code December 30, 2017
6.4.2 DTC 101001 High Battery Voltage CLG930E/936E

Component location

Front

Battery

Attached drawing

Alternator

Start motor
 6-17
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.2 DTC 101001 High Battery Voltage

Fault diagnosis and troubleshooting steps

Step 1 Check the battery voltage for fault

Notice: During the detection period, turn the start key switch to the OFF position.
Inspection method
Measure the battery voltage with the multimeter: Turn the multimeter to its DC voltage function (200V),
and connect the red probe to the positive battery terminal and the black probe to the negative battery
terminal. The schematic diagram for detection is as follows:

Black probe
Red probe

Normally, the battery (2 packs) voltage is about 25V.

Whether the battery voltage is abnormal or not?
YES NO
Repair or replace the battery
Go to Step 3 Go to Step 2
6-18
6.4 Fault Code December 30, 2017
6.4.2 DTC 101001 High Battery Voltage CLG930E/936E

Step 2 Check the alternator for faults

Notice: Pay special attention to the following when conduct the measurement with the
engine running: 1. Being scalded by overheated engine block. 2. Prevent the harnesses,
clothing and others from being drawn into the belts and the flywheel. 3. It is prohibited for the
complete machine to actuate.
Inspection method
Start the engine and measure the voltage (normally no more than 30V) between the alternator terminal
B+ and the grounding, by using a multimeter switching to the DC voltage position (200V), with
connecting the red probe to the alternator terminal B+ while the black probe to the grounding. For the
alternator location, see the figure

Connect the red probe to Connect the black

the generator B+ probe to ground

Whether the alternator fails?

YES NO
Contact local LiuGong dealer or authorized service
center.
Go to Step 3 Go to Step 3

Step 3 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-19
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.3 DTC 101017 Low Battery Voltage

6.4.3 DTC 101017 Low Battery System description

Voltage When the alternator does not work or generates
a low voltage, the battery supplies power to the
electrical equipment. When the engine starts, the
DTC Description Consequence
battery supplies power to the starter motor. After
Low battery voltage (the the machine is started, the battery is charged by
battery voltage detected It is difficult to the alternator. When the electrical equipment
101017
by the controller is low start the engine.
needs more power simultaneously and the
(16V-18V).)
alternator is overloaded, the battery assists the
alternator to supply power. A single battery has a
rated voltage of 12V. The complete machine is
powered by two batteries in series.
6-20
6.4 Fault Code December 30, 2017
6.4.3 DTC 101017 Low Battery Voltage CLG930E/936E

Component location

Front

Battery

Attached drawing

Alternator

Start motor
 6-21
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.3 DTC 101017 Low Battery Voltage

Fault diagnosis and troubleshooting steps

Step 1 Check the battery terminals for looseness or rust

Notice: Be sure to turn off the electric lock before checking whether the battery cables are
secured reliably.
Inspection method
Turn the battery terminals by hand or with the tools, and check them for looseness;
Visually check the terminals for rust.
Whether the battery terminals become loose or rusty?
YES NO
Tighten or derust
Go to Step 6 Go to Step 2
Step 2 Check whether the battery voltage is too low

Notice: Make sure the ignition switch is at the OFF position before assembling and
removing the battery cables. When assembling, install the positive terminals before the
negative terminals. Removal is the reverse of installation. This can avoid damage to the battery
terminals and the wrench due to short-circuit spark.
Notice: During the detection period, turn the start key switch to the OFF position
6-22
6.4 Fault Code December 30, 2017
6.4.3 DTC 101017 Low Battery Voltage CLG930E/936E

Inspection method
If the voltage below 18V, this indicates the battery voltage is too low. Low battery voltage may caused
by the three reasons: 1. Battery is not charged for a long time; 2 Battery is broken; 3. Insufficient
electricity. Check the battery in the following procedures:
1. Check the battery hydrometer. If the hydrometer becomes black, the battery needs to be charged. If
the hydrometer becomes white, the battery has been damaged. If the hydrometer is in the green
status, the battery is good.
Measure the battery voltage with the multimeter: Turn the multimeter to its DC voltage function (200V),
and connect the red probe to the positive battery terminal and the black probe to the negative battery
terminal. The schematic diagram for detection is as follows:

Black probe
Red probe

Is the battery voltage too low?

YES NO
Charge or replace the battery
Go to Step 6 Go to Step 3
Step 3 Check the charging harness for open-circuit (check whether the coupling ends become loose)

Notice: Pay special attention to the following when conduct the measurement with the
engine running: 1. Being scalded by overheated engine block. 2. Prevent the harnesses,
clothing and others from being drawn into the belts and the flywheel. 3. It is prohibited for the
complete machine to actuate.
Notice: Properly pack up the harness and leads: prevent the harness from being folded and
bent forcedly. It shall be kept away from moving components as far as possible to prevent
tensile failure and wear. Avoid friction with sharp metal edges. Keep away from oil and water as
far as possible. Keep away from high temperature parts (e.g. engine block) as far as possible.
 6-23
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.3 DTC 101017 Low Battery Voltage

Inspection method
1. Check the battery charging harness (# 120) for wear and its terminals for looseness
2. Check the charging harness for open-circuit with the multimeter: Method A: Turn the start key
switch to the OFF position. Turn the multimeter to its resistance function (200Ω), and measure the
resistance of the battery charging harness (# 120) (normally, <10Ω). For the alternator location and
the starter motor location, see the attached drawing

Start motor Alternator

Connect the multimeter probes to both ends

of the charging harness

Method B: Turn the start key switch to the ON position and turn the multimeter to its voltage function,
and then measure the voltage between the alternator terminal B and the grounding (normally, the
battery voltage about 25V).

Connect the red probe to Connect the black

the generator B+ probe to ground

Whether the charging harness is open-circuit or not (the coupling ends become loose)?
YES NO
Repair the harness or re-connect it
Go to Step 6 Go to Step 4
Step 4 Check whether the alternator fails or the output voltage is low

Notice: Pay special attention to the following when conduct the measurement with the
engine running: 1. Being scalded by overheated engine block. 2. Prevent the harnesses,
clothing and others from being drawn into the belts and the flywheel. 3. It is prohibited for the
complete machine to actuate.
6-24
6.4 Fault Code December 30, 2017
6.4.3 DTC 101017 Low Battery Voltage CLG930E/936E

Inspection method
After the complete machine is started, there are two possible causes for the alternator fault:
1. The belt is too loose.
2. Is there a fault in the alternator?
Check the battery in the following procedures:
1. Stop the engine and check whether the alternator belt becomes loose.
2. Start the engine, and measure the voltage between the alternator terminal B and the grounding with
the multimeter (normally, higher than the battery voltage)
Whether the alternator fails or its output voltage is low?
YES NO
1. Tighten or replace the drive belt
2. Contact local LiuGong dealer or authorized
service center.
Go to Step 6 Go to Step 5
Step 5 Check whether the controller power voltage is too low

Notice: Turn the start key switch to the ON position

Inspection method
1. Check the controller power line for wear and the coupling ends for looseness
2. Turn the multimeter to its DC voltage function (200V), and measure the voltage between the
controller power terminal (J1-2, J1-3, J1-4, J1-5, J1-6) and the grounding, respectively.
Whether the controller power voltage is too low?
YES NO
Repair the harness or re-connect it
Go to Step 6 Go to Step 6

Step 6 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-25
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.4 DTC 111001 System Charging Fault

6.4.4 DTC 111001 System System description

Charging Fault The alternator is accompanied with the engine,
and the silicon rectifier circuit and voltage
regulator with the frequency output are installed
DTC Description Consequence
in the alternator. After the engine is started, the
System charging fault alternator driven by the drive belt starts
Battery power
111001 (controller detects that generating (nominal voltage 28V). The current
loss.
the J2-28 port is 0V).
from the generating terminal (B+) flows through
the # 120 and #139 wires and the battery relay to
the battery to charge it. The charging indicator
signal terminal (P) is connected to the controller
J2-28 via the wire (# 928). The controller checks
whether the alternator is working properly
through the signal terminal.
6-26
6.4 Fault Code December 30, 2017
6.4.4 DTC 111001 System Charging Fault CLG930E/936E

Component location

Alternator

Front

Fault diagnosis and troubleshooting steps

Step 1 Check the alternator terminal P for electrical signal output (whether the alternator fails.).
Inspection method
1. Stop the engine and check whether the alternator belt becomes loose.
2. Start the engine and turn the multimeter to its voltage function, and then measure the voltage
between the alternator terminal P and ground (Normally, 14±0.5V).
Whether the alternator terminal P has no electrical signal output (the alternator fails)?
YES NO
Tighten or replace the belt
Contact your local LiuGong dealers and authorized
service centers.
Go to Step 3 Go to Step 3
 6-27
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.4 DTC 111001 System Charging Fault

Step 2 Check the harness for open-circuit

Notice: Properly pack up the harness and leads: prevent the harness from being folded and
bent forcedly. It shall be kept away from moving components as far as possible to prevent
tensile failure and wear. Avoid friction with sharp metal edges. Keep away from oil and water as
far as possible. Keep away from high temperature parts (e.g. engine block) as far as possible.
Inspection method
1. Check the # 928 harness (between the alternator terminal P and the J2-28 port) for wear.
2. Disconnect the connectors from the terminal P and the controller and check the harness for open-
circuit. Turn the multimeter to its resistance function, and measure the resistance of the harness (#
928) between the controller port J2-28 and the terminal P (normally, <10Ω).
Is the harness open-circuit?
YES NO
Repair and wrap the harness
Go to Step 3 Go to Step 3

Step 3 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-28
6.4 Fault Code December 30, 2017
6.4.5 DTC 121015 Oil Pressure Switch Disconnected CLG930E/936E

6.4.5 DTC 121015 Oil Pressure System description

Switch Disconnected The oil pressure switch is used for detecting the
engine oil pressure. Normally, the pressure
switch contact is closed. When the pressure
DTC Description Consequence
reaches 0.07MPa or more, the contact is open,
The display resulting in a safety overpressure less than
Oil pressure switch shows the oil 3.5MPa. Under normal circumstances, when the
121015
disconnected. pressure
engine is started, the engine oil pressure is
abnormally.
greater than 0.07MPa, and the pressure switch
contact should be open. The controller detects
the pressure switch signal. Then, if the engine oil
pressure is lower than 0.07MPa, the controller
will give alarm information via the display.

LG922E930E06011
LG922E930E060
Component location

Engine oil pressure switch

Front
 6-29
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.5 DTC 121015 Oil Pressure Switch Disconnected

Fault diagnosis and troubleshooting steps

Step 1 Check the oil pressure switch for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position, and disconnect the oil pressure switch connector:
1. Check the connector pins for looseness, rust, bending and damage.
2. Turn the multimeter to its resistance function, and measure the resistance between the oil pressure
switch connector terminals 1 and 2 (normally, <10Ω).
Whether the oil pressure switch fails?
YES NO
Repair or replace the oil pressure switch.
Go to Step 4 Go to Step 2
Step 2 Check the harness for open-circuit

Notice: Properly pack up the harness and leads: prevent the harness from being folded and
bent forcedly. It shall be kept away from moving components as far as possible to prevent
tensile failure and wear. Avoid friction with sharp metal edges. Keep away from oil and water as
far as possible. Keep away from high temperature parts (e.g. engine block) as far as possible.
Inspection method
1. Check the harness (# 902) and the grounding wire (# 283) between the controller (J2-02) and the oil
pressure switch for wear.
2. Disconnect the oil pressure switch connector and the controller connector, and check the harness
for open-circuit:
(1) Turn the multimeter to its resistance function, and measure the resistance between the grounding
wire (#283) switch terminal and the grounding (normally, <10Ω).
(2) Turn the multimeter to its resistance function, and measure the resistance of the harness between
the connector (C2-02) connected to the controller J2-02 and the switch (normally, <10Ω).
Is the harness open-circuit?
YES NO
Repair and wrap the harness
Go to Step 4 Go to Step 3
6-30
6.4 Fault Code December 30, 2017
6.4.5 DTC 121015 Oil Pressure Switch Disconnected CLG930E/936E

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the oil pressure switch connector and disconnect the controller connector. Turn the multimeter
to its resistance function, and measure the resistance between the connector C2-02 connecting to the
controller port J2-02 and the grounding (normally, <10Ω).
Whether the connector is faulty?
YES NO
Replace the connector.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-31
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.6 DTC 121018 Low Oil Pressure

6.4.6 DTC 121018 Low Oil System description

Pressure The oil pressure switch is used for detecting the
engine oil pressure. Normally, the pressure
switch contact is closed. When the pressure
DTC Description Consequence
reaches 0.07MPa or more, the contact is open,
Low oil pressure -- when resulting in a safety overpressure less than
If the machine is
the engine is running, 3.5MPa. Under normal circumstances, when the
operated as
the signal circuit of the oil
121018 usual, the engine engine is started, the engine oil pressure is
pressure switch detects
a low oil pressure (the
can be greater than 0.07MPa, and the pressure switch
damaged. contact should be open. The controller detects
sensor contact is open).
the pressure switch signal. Then, if the engine oil
pressure is lower than 0.07MPa, the controller
will give alarm information via the display.

LG922E930E06011
LG922E930E060
Component location

Engine oil pressure switch

Front
6-32
6.4 Fault Code December 30, 2017
6.4.6 DTC 121018 Low Oil Pressure CLG930E/936E

Fault diagnosis and troubleshooting steps

Step 1 Check the oil pressure is low or not

Inspection method
1. Pull out the oil dipstick, and check whether the oil level on the dipstick is below the MIN scale.
2. Check whether the oil pump is functioning properly.
3. Remove the oil pressure switch, and measure whether the oil pressure is too low with the pressure
gauge.
Whether the oil pressure is low or not?
YES NO
Troubleshoot and restore the oil pressure.
Go to Step 3 Go to Step 2

Step 2Whether the oil pressure monitoring system fails

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
When the oil pressure is normal, check the oil pressure detection circuit or the oil pressure switch
according to DTC "121015 - Oil Pressure Switch Disconnected"
Whether the oil pressure monitoring system fails?
YES NO
Repair the oil pressure detection circuit or replace
the oil pressure switch.
Go to Step 3 Go to Step 3

Step 3 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-33
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.7 DTC 121305 Hand Pilot Pressure Switch Disconnected

6.4.7 DTC 121305 Hand Pilot System description

Pressure Switch Disconnected The hand pilot pressure switch is used to detect
the hand pilot line pressure and the logic signal
input for the automatic idling function. After the
DTC Description Consequence
engine is started, open the pilot shut-off valve.
Hand pilot pressure No automatic Then, when the hand pilot control lever is not
121305
switch disconnected idling. operated, the pressure switch contact should be
closed. When the hand pilot control lever is
operated, the pressure switch contact should be
open. The automatic idling function can be
achieved only when the controller detects
simultaneously the hand pilot switch and foot
pilot switch signals, that is, when one or two pilot
pressure switches are unplugged, the automatic
idling function will be invalid.

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LG925E4F06027
6-34
6.4 Fault Code December 30, 2017
6.4.7 DTC 121305 Hand Pilot Pressure Switch Disconnected CLG930E/936E

Component location

Front

Foot pilot pressure switch

Hand pilot pressure switch

LG925E4F06028

Fault diagnosis and troubleshooting steps

Step 1 Check the hand pilot pressure switch for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position, and disconnect the connector from the hand pilot pressure
switch:
1. Check the connector pins for looseness, rust, bending and damage.
2. Turn the multimeter to its resistance function, and measure the resistance between the hand pilot
pressure switch connector terminals 1 and 2 (normally, <10Ω).

Connect the multimeter probes to

two pins of the hand pilot pressure
switch, respectively.

Whether the hand pilot pressure switch fails?

YES NO
Repair or replace the hand pilot pressure switch.
Go to Step 4 Go to Step 2
 6-35
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.7 DTC 121305 Hand Pilot Pressure Switch Disconnected

Step 2 Check the harness for open-circuit

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Check the harness (# 808) and the grounding wire (# 240) between the controller (J1-8) and the
hand pilot pressure switch for wear.
2. Disconnect the hand pilot pressure switch connector and the controller connector, and check the
harness for open-circuit:
(1) Turn the multimeter to its resistance function, and measure the resistance between the grounding
wire (#240) hand pilot pressure switch terminal and the grounding (normally, <10Ω).
Black probe

Gray wire
Red probe

(2) Turn the multimeter to its resistance function, and measure the resistance between the controller
terminals J1-8 and hand pilot pressure switch harness (normally, <10Ω).
To the black probe

To the red probe

White wire

Is the harness open-circuit?

YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
6-36
6.4 Fault Code December 30, 2017
6.4.7 DTC 121305 Hand Pilot Pressure Switch Disconnected CLG930E/936E

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
(3) Connect the hand pilot pressure switch connector and disconnect the controller connector. Turn the
multimeter to its resistance function, and measure the resistance between the harness at the
controller terminal J1-8 and the grounding (normally, <10Ω).
To the black probe

To the red probe

White wire

When the resistance is abnormal, this indicates the connector is poorly contacted.
Whether the connector is faulty?
YES NO
Replace the connector.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-37
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.8 DTC 121405 Foot Pilot Pressure Switch Disconnected

6.4.8 DTC 121405 Foot Pilot System description

Pressure Switch Disconnected The foot pilot pressure switch is used for
detecting the foot pilot line pressure and the logic
signal input for automatic idling function. After
DTC Description Consequence
the engine is started, open the pilot shut-off
Foot pilot pressure No automatic valve. When the foot pilot control lever is not
121405
switch disconnected. idling. operated, the pressure switch contact should be
closed. When the foot pilot control lever is
operated, the pressure switch contact should be
open. The automatic idling function can be
achieved only when the controller detects
simultaneously the foot pilot switch and foot pilot
switch signals, that is, when one or two pilot
pressure switches are unplugged, the automatic
idling function will be invalid.

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LG925E4F06027
6-38
6.4 Fault Code December 30, 2017
6.4.8 DTC 121405 Foot Pilot Pressure Switch Disconnected CLG930E/936E

Component location

Front

Foot pilot pressure switch

Hand pilot pressure switch

LG925E4F06028

Fault diagnosis and troubleshooting steps

Step 1 Check the foot pilot pressure switch for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position, and disconnect the foot pilot pressure switch connector:
1. Check the connector pins for looseness, rust, bending pin and damage.
2. Turn the multimeter to its resistance function, and measure the resistance between the foot pilot
pressure switch connector terminals 1 and 2 (normally, <10Ω).

Connect the multimeter probes to

two pins of the hand pilot pressure
switch, respectively.

Whether the foot pilot pressure switch fails?

YES NO
Repair or replace the foot pilot pressure switch.
Go to Step 2
Go to Step 4
 6-39
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.8 DTC 121405 Foot Pilot Pressure Switch Disconnected

Step 2 Check the harness for open-circuit

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Check the harness (# 913) and the grounding wire (# 240) between the controller (J2-13) and the
foot pilot pressure switch for wear.
2. Disconnect the foot pilot pressure switch connector and the controller connector and check the
harness for open-circuit:
(1) Turn the multimeter to its resistance function, and measure the resistance between the grounding
wire (#240) foot pilot pressure switch terminal and the grounding (normally, <10Ω).
Black probe

Gray wire
Red probe

(2) Turn the multimeter to its resistance function, and measure the resistance between the controller
terminals J2-13 and foot pilot pressure switch harness (normally, <10Ω).
To the black probe

To the red probe

White wire

Is the harness open-circuit?

YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
6-40
6.4 Fault Code December 30, 2017
6.4.8 DTC 121405 Foot Pilot Pressure Switch Disconnected CLG930E/936E

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the foot pilot pressure switch connector and disconnect the controller connector. Turn the
multimeter to its resistance function, and measure the resistance between the harness at the controller
terminal J2-13 and the grounding (normally, <10Ω).

To the black probe

To the red probe

White wire

When the resistance is abnormal, this indicates the connector is poorly contacted.
Whether the connector is faulty?
YES NO
Replace the connector.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-41
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.9 DTC 121604 Air Filter Switch Shorted to Ground

6.4.9 DTC 121604 Air Filter Switch System description

Shorted to Ground The air pre-filter is used to filter the dust and
large impurities in the air before entering the air
filter. The air filter mounted on the inside of the
DTC Description Consequence
left door of the complete machine is used to filter
If the machine is further the air from the prefilter, and keep the air
operated as clean and dry through the main filter element and
Air filter switch shorted to
121604 usual, the engine
ground safety filter element before entering into the
can be
damaged. engine cylinders for combustion. When the
airflow through the air filter is blocked and the air
filter is needed to work, then if the engine is
running, a high vacuum between the air filter and
the engine will produce. The vacuum can
activate the electronic indicator (air filter switch)
to generate ground which is transmitted to the
controller. The display will show the current
situation to alert the operator.

Component location

Front

Air filter switch

LG925E4F06042
6-42
6.4 Fault Code December 30, 2017
6.4.9 DTC 121604 Air Filter Switch Shorted to Ground CLG930E/936E

Fault diagnosis and troubleshooting steps

Step 1 Check the air filter switch for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position, and disconnect the connector from the air filter switch:
1. Check the connector inside for moisture, oil dirt and other.
2. Turn the multimeter to its resistance function, and measure the resistance between the air filter
switch terminals (normally, >100kΩ).
Whether the air filter switch fails?
YES NO
Repair or replace the air filter switch.
Go to Step 3 Go to Step 2

Step 2 Check whether the harness is shorted to ground

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Check the harness (# 927) between the controller (J2-27) and the air filter switch for wear.
2. Disconnect the air filter switch connector and the controller connector. Turn the multimeter to its
resistance function, and measure the resistance between the harness (# 927) switch terminal and
the grounding (normally, >100kΩ).
Whether the harness is shorted to ground or not?
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
 6-43
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.9 DTC 121604 Air Filter Switch Shorted to Ground

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the air filter switch connector and disconnect the controller connector. Turn the multimeter to
its resistance function, and measure the resistance between the controller port J2-27 and the grounding
(normally, >100kΩ)
When the resistance is abnormal, this indicates there is an insulation fault in the connector.
Whether the connector is faulty?
YES NO
Replace the connector.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-44
6.4 Fault Code December 30, 2017
6.4.10 DTC 121615 Air Filter Clogging CLG930E/936E

6.4.10 DTC 121615 Air Filter System description

Clogging The air pre-filter is used to filter the dust and
large impurities in the air before entering the air
filter. The air filter mounted on the inside of the
DTC Description Consequence
left door of the complete machine is used to filter
Air filter clogging -- when further the air from the prefilter, and keep the air
the engine is running, If the machine is clean and dry through the main filter element and
the signal circuit of the operated as
safety filter element before entering into the
121615 air filter switch detects usual, the engine
the air filter is clogged can be engine cylinders for combustion. When the
(the sensor contact is damaged. airflow through the air filter is blocked and the air
closed). filter is needed to work, then if the engine is
running, a high vacuum between the air filter and
the engine will produce. The vacuum can
activate the electronic indicator (air filter switch)
to generate ground which is transmitted to the
controller. The display will show the current
situation to alert the operator.

Component location

Front

Air filter switch

LG925E4F06042
 6-45
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.10 DTC 121615 Air Filter Clogging

Fault diagnosis and troubleshooting steps

Step 1 Check whether the air filter is clogged

Inspection method
Check whether the air filter is clogged
Whether the air filter is clogged?
YES NO
Repair or replace the air filter.
Go to Step 3 Go to Step 2

Step 2 Check the air filter monitoring system for fault.

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
If the air filter is normal, check the air filter detection circuit or air filter alarm switch for fault in
accordance with the fault diagnosis of the 121604- Air Filter Switch Shorted to Ground.
Whether the air filter monitoring system fails?
YES NO
Repair the air filter detection circuit or replace the
air filter alarm switch
Go to Step 3 Go to Step 3

Step 3 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-46
6.4 Fault Code December 30, 2017
6.4.11 DTC 131000 High Engine Speed CLG930E/936E

6.4.11 DTC 131000 High Engine System description

Speed The speed sensor is used for detecting the
engine speed which can be read on the display.
The speed sensor is an electromagnetic
DTC Description Consequence
induction sensor, which is mounted on the diesel
High engine speed - engine flywheel housing. The diesel engine
If the machine is
When the engine is flywheel cuts the magnetic field lines, resulting in
operated as
running, the signal circuit
131000 usual, the engine an EMF and output current. After starting the
of the speed sensor
detects the engine speed
can be engine, let it run at 1000 ~ 2270r/min, and then
damaged. turn the multimeter to its AC voltage function,
is too high.
and measure the speed sensor output voltage of
3~28V.

Component location

Speed sensor
Front
 6-47
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.11 DTC 131000 High Engine Speed

Fault diagnosis and troubleshooting steps

Step 1 Check whether the operating method is incorrect

Inspection method
Check whether the operator’s operating method is correct.
Whether the operating method is incorrect or not?
YES NO
Train the operator to use correct operating
method. Go to Step 2
Go to Step 4

Step 2 Check whether the fuel is used properly

Notice: Be careful! Hot engine block and hydraulic oil can cause serious scald.
Inspection method
Check whether the fuel being used is the specified one.
Whether the fuel is used improperly or not?
YES NO
Replace the fuel
Go to Step 3
Go to Step 4
Step 3 Check the detection circuit or speed sensor for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Check the speed detection circuit or speed sensor for fault in accordance with the fault diagnosis of the
131005- Engine Speed Sensor Fault.
Whether the detection circuit speed sensor is faulty?
YES NO
Repair the detection circuit or replace the speed
sensor. Go to Step 4
Go to Step 4
6-48
6.4 Fault Code December 30, 2017
6.4.11 DTC 131000 High Engine Speed CLG930E/936E

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-49
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.12 DTC 131100 Extremely High Coolant Temperature

6.4.12 DTC 131100 Extremely High System description

Coolant Temperature The temperature sensor is made of NTC
temperature sensing material and is used for
detecting coolant temperature. The temperature
DTC Description Consequence
sensor is a negative temperature coefficient
Extremely high coolant thermistor type, i.e., the lower the temperature,
temperature - When the the larger the resistance. Therefore, the
engine is running, the If carrying on
temperature change is converted into a
signal circuit of the operation of
131100 engine coolant machine, it may resistance voltage signal output to the controller
temperature sensor lead to engine which detects the coolant temperature. The
detects that the engine cylinder scuffing. coolant temperature appears on the connected
coolant is overheating display instrument. When the coolant
(108 °). temperature is higher than a certain value, an
alarm signal is sent.

Component location

Coolant temperature
sensor

Front
6-50
6.4 Fault Code December 30, 2017
6.4.12 DTC 131100 Extremely High Coolant Temperature CLG930E/936E

Fault diagnosis and troubleshooting steps

Step 1 Check the engine coolant for overheating

Notice: Be careful! Hot engine block and coolant can scald you seriously
Inspection method
Check the engine coolant for overheating with a thermometer.
Whether the engine coolant overheating or not?
YES NO
Look for the cause for the engine coolant
overheating. Go to Step 2
Go to Step 3
Step 2 Check the engine coolant temperature monitoring system for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
If the coolant temperature is normal, check the coolant temperature detection circuit or coolant
temperature sensor for fault in accordance with the fault diagnosis of 131103- Coolant Temperature
Sensor Voltage Outside the Range Value.
Whether the engine coolant temperature monitoring system fails or not?
YES NO
Repair the coolant temperature detection circuit or
replace the coolant temperature sensor. Go to Step 3
Go to Step 3

Step 3 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-51
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.13 DTC 131103 Coolant Temperature Sensor Voltage Above the Range Value

6.4.13 DTC 131103 Coolant System description

Temperature Sensor Voltage The temperature sensor is made of NTC
Above the Range Value temperature sensing material and is used for
detecting coolant temperature. The temperature
sensor is a negative temperature coefficient
DTC Description Consequence thermistor type, i.e., the lower the temperature,
The controller detects the larger the resistance. Therefore, the
If carrying on
the coolant temperature temperature change is converted into a
operation of
131103
sensor voltage is higher
machine, it may
resistance voltage signal output to the controller
than the range value, which detects the coolant temperature. The
lead to engine
that is, the detected coolant temperature appears on the connected
cylinder scuffing.
voltage is above 4.9V.
display instrument. When the coolant
temperature is higher than a certain value, an
alarm signal is sent.

Coolant temperature sensor parameter table

Coolant temperature
(Celsius degree )
Resistance (Ohm)
6-52
6.4 Fault Code December 30, 2017
6.4.13 DTC 131103 Coolant Temperature Sensor Voltage Above the Range Value CLG930E/936E

Component location

Coolant temperature
sensor

Front

Fault diagnosis and troubleshooting steps

Step 1 Check the coolant temperature sensor for fault

Inspection method
Turn the knob switch to the OFF position, and disconnect the sensor connector:
1. Check the connector for looseness, rust, bending and damage.
2. Turn the multimeter to its resistance function (20kΩ), and measure the resistance between the
sensor connector terminals 1 and 2, comparing the result with the parameter table (normally, <4kΩ).
Whether a fault developing in the coolant temperature sensor or not?
YES NO
Repair or replace the sensor.
Go to Step 4 Go to Step 2

Step 2 Check the harness for open-circuit

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Check the harnesses (# 819 and # 922) between the controller (J1-19 and J2-22) and the coolant
temperature sensor for wear, respectively.
2. Disconnect the coolant temperature sensor connector and the controller connector: Turn the
multimeter to its resistance function, and measure the resistance of the harness (# 819 and # 922)
between the controller (J1-19 and J2-22) and the sensor, respectively (normally, <10Ω).
 6-53
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.13 DTC 131103 Coolant Temperature Sensor Voltage Above the Range Value

Is the harness open-circuit?

YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the coolant temperature sensor connector and disconnect the controller connector. Turn the
multimeter to its resistance function, measure the resistance between the controller port J1-19 and J2-
22, and compare the result with the parameter table (normally, <4K).
An abnormal resistance indicates that there is poor contact in the connector
Whether the connector is faulty?
YES NO
Replace the connector.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-54
6.4 Fault Code December 30, 2017
6.4.14 DTC 131104 Coolant Temperature Sensor Voltage Below the Range Value CLG930E/936E

6.4.14 DTC 131104 Coolant System description

Temperature Sensor Voltage The temperature sensor is made of NTC
Below the Range Value temperature sensing material and is used for
detecting coolant temperature. The temperature
sensor is a negative temperature coefficient
DTC Description Consequence thermistor type, i.e., the lower the temperature,
Coolant temperature the larger the resistance. Therefore, the
sensor voltage below the temperature change is converted into a
range value (When the resistance voltage signal output to the controller
engine is running, the If the machine is which detects the coolant temperature. The
signal circuit of the operated as coolant temperature appears on the connected
131104 engine coolant usual, it may
display instrument. When the coolant
temperature sensor cause engine
detects that the engine power decrease. temperature is higher than a certain value, an
coolant temperature is alarm signal is sent.
too high and above the
measurable range)

LG922E930E06027
Coolant temperature sensor parameter table

Coolant temperature
(Celsius degree )
Resistance (Ohm)
 6-55
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.14 DTC 131104 Coolant Temperature Sensor Voltage Below the Range Value

Component location

Coolant temperature
sensor

Front

Fault diagnosis and troubleshooting steps

Step 1 Check the coolant temperature sensor for fault

Inspection method
Turn the knob switch to the OFF position, and disconnect the sensor connector:
1. Check the connector for looseness, rust, bending and damage.
2. Turn the multimeter to its resistance function (20kΩ), and measure the resistance between the
sensor connector terminals 1 and 2, comparing the result with the parameter table (normally, <4kΩ).
Whether a fault developing in the coolant temperature sensor or not?
YES NO
Repair or replace the sensor.
Go to Step 4 Go to Step 2

Step 2 Check whether the harness is shorted to ground

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Check the harnesses (# 819 and # 922) between the controller (G1 and B1) and the coolant
temperature sensor for wear.
2. Disconnect the connectors from the coolant temperature sensor and the controller. Turn the
multimeter to its resistance function, and measure the resistance of the harness (# 819/# 922)
between the controller (G1/ B1) and the sensor, respectively (normally, >100Ω).
6-56
6.4 Fault Code December 30, 2017
6.4.14 DTC 131104 Coolant Temperature Sensor Voltage Below the Range Value CLG930E/936E

Whether the harness is shorted to ground or not?

YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the coolant temperature sensor connector and disconnect the controller connector. Turn the
multimeter to its resistance function, measure the resistance between the controller port J1-19 and J2-
22, and compare the result with the parameter table (normally, >10Ω)
When the resistance is abnormal, this indicates there is an insulation fault in the connector
Whether the connector is faulty?
YES NO
Replace the connector.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-57
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.15 DTC 131115 High Coolant Temperature

6.4.15 DTC 131115 High Coolant System description

Temperature The temperature sensor is made of NTC
temperature sensing material and is used for
detecting coolant temperature. The temperature
DTC Description Consequence
sensor is a negative temperature coefficient
High coolant thermistor type, i.e., the lower the temperature,
temperature - When the the larger the resistance. Therefore, the
engine is running, the If carrying on
temperature change is converted into a
signal circuit of the operation of
131115 engine coolant machine, it may resistance voltage signal output to the controller
temperature sensor lead to engine which detects the coolant temperature. The
detects that the engine cylinder scuffing coolant temperature appears on the connected
coolant is overheating display instrument. When the coolant
(102°C). temperature is higher than a certain value, an
alarm signal is sent.

LG922E930E06027

Component location

Coolant temperature
sensor

Front
6-58
6.4 Fault Code December 30, 2017
6.4.15 DTC 131115 High Coolant Temperature CLG930E/936E

Fault diagnosis and troubleshooting steps

Step 1 Check whether the engine coolant temperature is too high

Notice: Be careful! Hot engine block and coolant can scald you seriously
Inspection method
Check whether the engine coolant temperature is too high with a thermometer
Whether the engine coolant overheating or not?
YES NO
Look for the cause for high coolant temperature.
Go to Step 3 Go to Step 2

Step 2 Check the engine coolant temperature monitoring system for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
If the coolant temperature is normal, check the coolant temperature detection circuit or coolant
temperature sensor for fault in accordance with the fault diagnosis of 131103- Coolant Temperature
Sensor Voltage Above the Range Value.
Whether the engine coolant temperature monitoring system fails or not?
YES NO
Repair the coolant temperature detection circuit or
replace the coolant temperature sensor.
Go to Step 3 Go to Step 3

Step 3 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-59
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.16 DTC 131116 High Coolant Temperature

6.4.16 DTC 131116 High Coolant System description

Temperature The temperature sensor is made of NTC
temperature sensing material and is used for
detecting coolant temperature. The temperature
DTC Description Consequence
sensor is a negative temperature coefficient
High coolant thermistor type, i.e., the lower the temperature,
temperature - When the the larger the resistance. Therefore, the
engine is running, the If carrying on
temperature change is converted into a
signal circuit of the operation of
131116 engine coolant machine, it may resistance voltage signal output to the controller
temperature sensor lead to engine which detects the coolant temperature. The
detects that the engine cylinder scuffing coolant temperature appears on the connected
coolant is overheating display instrument. When the coolant
(105°C). temperature is higher than a certain value, an
alarm signal is sent.

Component location

Coolant temperature
sensor

Front
6-60
6.4 Fault Code December 30, 2017
6.4.16 DTC 131116 High Coolant Temperature CLG930E/936E

Fault diagnosis and troubleshooting steps

Step 1 Check whether the engine coolant temperature is too high

Notice: Hot engine block and coolant can scald you seriously
Inspection method
Check whether the engine coolant temperature is too high with a thermometer
Whether the engine coolant overheating or not?
YES NO
Look for the cause for high coolant temperature.
Go to Step 3 Go to Step 2

Step 2 Check the engine coolant temperature monitoring system for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
If the coolant temperature is normal, check the coolant temperature detection circuit or coolant
temperature sensor for fault in accordance with the fault diagnosis of 131103- Coolant Temperature
Sensor Voltage Above the Range Value.
Whether the engine coolant temperature monitoring system fails or not?
YES NO
Repair the coolant temperature detection circuit or
replace the coolant temperature sensor.
Go to Step 3 Go to Step 3

Step 3 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-61
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.17 DTC 131200 Extremely High Hydraulic Oil Temperature

6.4.17 DTC 131200 Extremely High System description

Hydraulic Oil Temperature The temperature sensor is made of NTC
temperature sensing material and is used for
detecting hydraulic oil (cooling water). The
DTC Description Consequence
temperature sensor is a negative temperature
Extremely high hydraulic coefficient thermistor type, i.e., the lower the
oil temperature -- when If the machine is temperature, the larger the resistance.
the engine is running, operated as
Therefore, the temperature change is converted
the signal circuit of the usual, the
131200
hydraulic oil temperature hydraulic into a resistance voltage signal output to the
sensor detects the components can controller which detects the temperature of the
hydraulic oil temperature be damaged. hydraulic oil (cooling water). The temperature of
is extremely high (95°C). the hydraulic oil (cooling water) appears on the
connected display instrument. When the water
temperature is higher than a certain value, an
alarm signal is sent.

Component location

Front

Hydraulic oil
temperature sensor
6-62
6.4 Fault Code December 30, 2017
6.4.17 DTC 131200 Extremely High Hydraulic Oil Temperature CLG930E/936E

Fault diagnosis and troubleshooting steps

Step 1 Check whether the hydraulic oil temperature is extremely high

Notice: Be careful! Hot engine block and hydraulic oil can cause serious scald.
Inspection method
Check the hydraulic oil is not too high by using a thermometer.
Whether the hydraulic oil temperature is extremely high or not?
YES NO
Troubleshoot the high hydraulic oil temperature.
Go to Step 3 Go to Step 2

Step 2 Check the hydraulic oil temperature monitoring system for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
If the hydraulic oil temperature is normal, check the hydraulic oil temperature detection circuit or
hydraulic oil temperature sensor for fault in accordance with the DTC 131203 - Hydraulic Oil
Temperature Sensor Voltage Above the Range Value.
Whether the hydraulic oil temperature monitoring system fails?
YES NO
Repair the hydraulic oil temperature detection
circuit or replace the hydraulic oil temperature
sensor.
Go to Step 3 Go to Step 3

Step 3 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-63
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.18 DTC 131203 Hydraulic oil Temperature Sensor Voltage Above the Range Value

6.4.18 DTC 131203 Hydraulic oil System description

Temperature Sensor Voltage The temperature sensor is made of NTC
Above the Range Value temperature sensing material and is used for
detecting hydraulic oil (cooling water). The
temperature sensor is a negative temperature
DTC Description Consequence coefficient thermistor type, i.e., the lower the
If continue to temperature, the larger the resistance.
The controller detects the
operate the Therefore, the temperature change is converted
hydraulic oil temperature
sensor voltage is higher
machine, it may into a resistance voltage signal output to the
131203 cause pump controller which detects the temperature of the
than the range value, that
power decrease hydraulic oil (cooling water). The temperature of
is, the detected voltage is
and hydraulic
above 4.9V. the hydraulic oil (cooling water) appears on the
seals damaged.
connected display instrument. When the water
temperature is higher than a certain value, an
alarm signal is sent.

LG922E930E06030

Hydraulic oil temperature sensor parameter table

Coolant temperature
(Celsius degree )
Resistance (Ohm)
6-64
6.4 Fault Code December 30, 2017
6.4.18 DTC 131203 Hydraulic oil Temperature Sensor Voltage Above the Range Value CLG930E/936E

Component location

Front

Hydraulic oil
temperature sensor

Fault diagnosis and troubleshooting steps

Step 1 Check the hydraulic oil temperature sensor for fault

Inspection method
Turn the knob switch to the OFF position, and disconnect the sensor connector:
1. Check the connector for looseness, rust, bending and damage.
2. Turn the multimeter to its resistance function (20kΩ), and measure the resistance between the
sensor connector terminals 1 and 2, comparing the result with the parameter table (normally, <4kΩ).
Whether the hydraulic oil temperature sensor fails?
YES NO
Repair or replace the sensor.
Go to Step 4 Go to Step 2

Step 2 Check the harness for open-circuit

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
 6-65
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.18 DTC 131203 Hydraulic oil Temperature Sensor Voltage Above the Range Value

Inspection method
1. Check the harnesses (# 831 and # 922) between the controller (J1-31 and J2-22 ) and the hydraulic
oil temperature sensor for wear.
2. Disconnect the connectors from the hydraulic oil temperature sensor and the controller. Turn the
multimeter to its resistance function, and measure the resistance of the harness (# 831/# 922)
between the controller (J1-31/J2-22 ) and the hydraulic oil temperature sensor, respectively
(normally, <10Ω)
Is the harness open-circuit?
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the hydraulic oil temperature sensor connector and disconnect the controller connector. Turn
the multimeter to its resistance function, and measure the resistance between the controller port J1-31
and J2-22, comparing the result with the parameter table (normally, <4kΩ).
An abnormal resistance indicates that there is poor contact in the connector
Whether the connector is faulty?
YES NO
Replace the connector.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-66
6.4 Fault Code December 30, 2017
6.4.19 DTC 131204 Hydraulic Oil Temperature Sensor Voltage Below the Range Value CLG930E/936E

6.4.19 DTC 131204 Hydraulic Oil System description

Temperature Sensor Voltage The temperature sensor is made of NTC
Below the Range Value temperature sensing material and is used for
detecting hydraulic oil (cooling water). The
temperature sensor is a negative temperature
DTC Description Consequence coefficient thermistor type, i.e., the lower the
If the machine is temperature, the larger the resistance.
The hydraulic oil operated as Therefore, the temperature change is converted
131204
temperature sensor usual, the into a resistance voltage signal output to the
voltage is below the hydraulic controller which detects the temperature of the
range valve. pipeline can be hydraulic oil (cooling water). The temperature of
damaged.
the hydraulic oil (cooling water) appears on the
connected display instrument. When the water
temperature is higher than a certain value, an
alarm signal is sent.

LG922E930E06030

Hydraulic oil temperature sensor parameter table

Coolant temperature
(Celsius degree )
Resistance (Ohm)
 6-67
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.19 DTC 131204 Hydraulic Oil Temperature Sensor Voltage Below the Range Value

Component location

Front

Hydraulic oil
temperature sensor

Fault diagnosis and troubleshooting steps

Step 1 Check the hydraulic oil temperature sensor for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the knob switch to the OFF position, and disconnect the sensor connector:
1. Check the connector for looseness, rust, bending and damage.
2. Turn the multimeter to its resistance function (20kΩ), and measure the resistance between the
sensor connector terminals 1 and 2, comparing the result with the parameter table (normally, <4kΩ).
Whether the hydraulic oil temperature sensor fails?
YES NO
Repair or replace the sensor.
Go to Step 4 Go to Step 2

Step 2 Check whether the harness is shorted to ground

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
6-68
6.4 Fault Code December 30, 2017
6.4.19 DTC 131204 Hydraulic Oil Temperature Sensor Voltage Below the Range Value CLG930E/936E

Inspection method
1. Check the harnesses (# 831 and # 922) between the controller (J1-31 and J2-22 ) and the hydraulic
oil temperature sensor for wear.
2. Disconnect the connectors from the hydraulic oil temperature sensor and the controller. Turn the
multimeter to its resistance function, and measure the resistance between the harness (# 831/#
922) sensor terminal and the grounding, respectively (normally, >100K).
Whether the harness is shorted to ground or not?
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the hydraulic oil temperature sensor connector and disconnect the controller connector. Turn
the multimeter to its resistance function, and measure the resistance between the controller port J1-31
and J2-22, comparing the result with the parameter table (normally, >10Ω).
When the resistance is abnormal, this indicates there is an insulation fault in the connector
Whether the connector is faulty?
YES NO
Replace the connector.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-69
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.20 DTC 131215 High Hydraulic Oil Temperature

6.4.20 DTC 131215 High Hydraulic System description

Oil Temperature The temperature sensor is made of NTC
temperature sensing material and is used for
detecting hydraulic oil (cooling water). The
DTC Description Consequence
temperature sensor is a negative temperature
High hydraulic oil coefficient thermistor type, i.e., the lower the
temperature -- when the If the machine is temperature, the larger the resistance.
engine is running, the operated as
Therefore, the temperature change is converted
signal circuit of the usual, the
131215
hydraulic oil temperature hydraulic into a resistance voltage signal output to the
sensor detects the components can controller which detects the temperature of the
hydraulic oil temperature be damaged. hydraulic oil (cooling water). The temperature of
is extremely high (86°C). the hydraulic oil (cooling water) appears on the
connected display instrument. When the water
temperature is higher than a certain value, an
alarm signal is sent.

Component location

Front

Hydraulic oil
temperature sensor
6-70
6.4 Fault Code December 30, 2017
6.4.20 DTC 131215 High Hydraulic Oil Temperature CLG930E/936E

Fault diagnosis and troubleshooting steps

Step 1 Check whether the hydraulic oil temperature is too high

Notice: Be careful! Hot engine block and hydraulic oil can cause serious scald.
Inspection method
Check the hydraulic oil is not too high by using a thermometer.
Whether the hydraulic oil temperature is too high or not?
YES NO
Troubleshoot the high hydraulic oil temperature.
Go to Step 3 Go to Step 2

Step 2 Check the hydraulic oil temperature monitoring system for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
If the hydraulic oil temperature is normal, check the hydraulic oil temperature detection circuit or
hydraulic oil temperature sensor for fault in accordance with the DTC 131203 - Hydraulic Oil
Temperature Sensor Voltage Above the Range Value.
Whether the hydraulic oil temperature monitoring system fails?
YES NO
Repair the hydraulic oil temperature detection
circuit or replace the hydraulic oil temperature
sensor.
Go to Step 3 Go to Step 3

Step 3 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-71
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.21 DTC 131216 Extremely High Hydraulic Oil Temperature

6.4.21 DTC 131216 Extremely High System description

Hydraulic Oil Temperature The temperature sensor is made of NTC
temperature sensing material and is used for
detecting hydraulic oil (cooling water). The
DTC Description Consequence
temperature sensor is a negative temperature
Very high hydraulic oil coefficient thermistor type, i.e., the lower the
temperature - When the If the machine is temperature, the larger the resistance.
engine is running, the operated as
Therefore, the temperature change is converted
signal circuit of the usual, the
131216
hydraulic oil temperature hydraulic into a resistance voltage signal output to the
sensor detects the components can controller which detects the temperature of the
hydraulic oil temperature be damaged. hydraulic oil (cooling water). The temperature of
is high (88°C). the hydraulic oil (cooling water) appears on the
connected display instrument. When the water
temperature is higher than a certain value, an
alarm signal is sent.

Component location

Front

Hydraulic oil
temperature sensor
6-72
6.4 Fault Code December 30, 2017
6.4.21 DTC 131216 Extremely High Hydraulic Oil Temperature CLG930E/936E

Fault diagnosis and troubleshooting steps

Step 1 Check whether the hydraulic oil temperature is extremely high

Notice: Be careful! Hot engine block and hydraulic oil can cause serious scald.
Inspection method
Check whether the hydraulic oil is not very high with a thermometer.
Whether the hydraulic oil temperature is extremely high or not?
YES NO
Troubleshoot the high hydraulic oil temperature.
Go to Step 3 Go to Step 2

Step 2 Check the hydraulic oil temperature monitoring system for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
If the hydraulic oil temperature is normal, check the hydraulic oil temperature detection circuit or
hydraulic oil temperature sensor for fault in accordance with the DTC 131203 - Hydraulic Oil
Temperature Sensor Voltage Above the Range Value.
Whether the hydraulic oil temperature monitoring system fails?
YES NO
Repair the hydraulic oil temperature detection
circuit or replace the hydraulic oil temperature
sensor.
Go to Step 3 Go to Step 3

Step 3 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-73
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.22 DTC 131303 Fuel Level Sensor Voltage Above the Range Value

6.4.22 DTC 131303 Fuel Level System description

Sensor Voltage Above the Range The fuel level sensor is a reed pipe type. The
Value magnetic floater density is lower than the
working medium (diesel) density, so the fuel level
sensor floats on the surface of the working
DTC Description Consequence medium and can slide up and down on the reed
If the machine is pipe. When the floater moves on the reed pipe,
Fuel level sensor voltage operated as the on-off of the internal circuit of the reed pipe is
131303
above the range value usual, the engine controlled by a magnetic field to allow the
will shut down. resistance between the two output leads of the
connector to change. Therefore, the fuel level
change is converted into a resistance signal
output, and through connecting to the controller
the fuel level in the tank is detected, and through
connecting to the display instrument the fuel
level is displayed.

LG922E930E06032

Fuel level sensor parameter table

Floater position Floater position

Output resistance Output resistance
(Refer to the place at (Refer to the place at
(Ω) (Ω)
17.5mm) 17.5mm)
Below L1 1100±11.0 L11-L12 550±5.5
L1-L2 1050±10.5 L12-L13 500±5.0
L2-L3 1000±10.0 L13-L14 450±4.5
L3-L4 950±9.5 L14-L15 400±4.0
L4-L5 900±9.0 L15-L16 350±3.5
L5-L6 850±8.5 L16-L17 300±3.0
L6-L7 800±8.0 L17-L18 250±2.5
L7-L8 750±7.5 L18-L19 200±2.0
L8-L9 700±7.0 L19-L20 150±1.5
L9-L10 650±6.5 L20-L21 100±1.0
L0-L11 600±6.0
6-74
6.4 Fault Code December 30, 2017
6.4.22 DTC 131303 Fuel Level Sensor Voltage Above the Range Value CLG930E/936E

Oil level

Component location

Front

Fuel level sensor

 6-75
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.22 DTC 131303 Fuel Level Sensor Voltage Above the Range Value

Fault diagnosis and troubleshooting steps

Step 1 Check the fuel level sensor for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Notice: High temperature and high pressure oil or water can cause personal injury! When
replacing the sensor, please shut down the engine first and wait until the engine and gearbox
housing are sufficiently cooled.
Notice: When installing the fuel level sensor into the fuel tank, wipe off the water and keep
it clean.
Inspection method
Turn the start switch to the OFF position, and disconnect the connector from the fuel level sensor:
1. Check the connector for looseness, rust, bending and damage.
2. Turn the multimeter to its resistance function, and measure the resistance between the fuel level
sensor connector terminals 1 and 2 (normally, <2kΩ, for the specific resistance, see the figure.).

Whether the fuel level sensor fails?

YES NO
Repair or replace the sensor.
Go to Step 4 Go to Step 2
6-76
6.4 Fault Code December 30, 2017
6.4.22 DTC 131303 Fuel Level Sensor Voltage Above the Range Value CLG930E/936E

Step 2 Check whether the harness is shorted to ground

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Check the harness (# 930) and the grounding wire (#227) between the controller (J2-30) and fuel
level sensor for wear.
2. Disconnect the fuel level sensor connector and the controller connector. Check the harness for
open-circuit:
(1) Turn the multimeter to its resistance function, and measure the resistance between the grounding
wire (#227) sensor terminal and the grounding (normally, <10Ω).

Gray wire

(2) Turn the multimeter to its resistance function, and measure the resistance between the connector
terminals J2-30 and sensor harness (normally, <10Ω).

 


White wire

 

To the black probe

To the red probe
LG925E4F06057

Whether the harness is shorted to ground or not?

 6-77
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.22 DTC 131303 Fuel Level Sensor Voltage Above the Range Value

YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the fuel-level sensor connector and disconnect the controller connector. Turn the multimeter to
its resistance function, and measure the resistance between the harness at the controller port J2-30
and the grounding (normally, <2 kΩ, for the specific resistance, see fuel level sensor parameter table).
When the resistance is abnormal, this indicates the connector is poorly contacted.
Whether the connector is faulty?
YES NO
Replace the connector.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-78
6.4 Fault Code December 30, 2017
6.4.23 DTC 131304 Fuel Level Sensor Shorted to Ground CLG930E/936E

6.4.23 DTC 131304 Fuel Level System description

Sensor Shorted to Ground The fuel level sensor is a reed pipe type. The
magnetic floater density is lower than the
working medium (diesel) density, so the fuel level
DTC Description Consequence
sensor floats on the surface of the working
If the machine is medium and can slide up and down on the reed
The fuel level sensor is operated as pipe. When the floater moves on the reed pipe,
131304
shorted to ground usual, the engine
the on-off of the internal circuit of the reed pipe is
will shut down.
controlled by a magnetic field to allow the
resistance between the two output leads of the
connector to change. Therefore, the fuel level
change is converted into a resistance signal
output, and through connecting to the controller
the fuel level in the tank is detected, and through
connecting to the display instrument the fuel
level is displayed.

LG922E930E06032

Fuel level sensor parameter table

Floater position Floater position

Output resistance Output resistance
(Refer to the place at (Refer to the place at
(Ω) (Ω)
17.5mm) 17.5mm)
Below L1 1100±11.0 L11-L12 550±5.5
L1-L2 1050±10.5 L12-L13 500±5.0
L2-L3 1000±10.0 L13-L14 450±4.5
L3-L4 950±9.5 L14-L15 400±4.0
L4-L5 900±9.0 L15-L16 350±3.5
L5-L6 850±8.5 L16-L17 300±3.0
L6-L7 800±8.0 L17-L18 250±2.5
L7-L8 750±7.5 L18-L19 200±2.0
L8-L9 700±7.0 L19-L20 150±1.5
L9-L10 650±6.5 L20-L21 100±1.0
L0-L11 600±6.0
 6-79
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.23 DTC 131304 Fuel Level Sensor Shorted to Ground

Oil level

Component location

Front

Fuel level sensor

6-80
6.4 Fault Code December 30, 2017
6.4.23 DTC 131304 Fuel Level Sensor Shorted to Ground CLG930E/936E

Fault diagnosis and troubleshooting steps

Step 1 Check the fuel level sensor for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Notice: High temperature and high pressure oil or water can cause personal injury! When
replacing the sensor, please shut down the engine first and wait until the engine and gearbox
housing are sufficiently cooled.
Notice: When installing the fuel level sensor into the fuel tank, wipe off the water and keep
it clean.
Inspection method
Turn the start switch to the OFF position, and disconnect the connector from the fuel level sensor:
1. Check the connector for looseness, rust, bending and damage.
2. Turn the multimeter to its resistance function, and measure the resistance between the fuel level
sensor connector terminals 1 and 2 (normally, <2kΩ, for the specific resistance, see the figure.).

Whether the fuel level sensor fails?

YES NO
Repair or replace the sensor.
Go to Step 4 Go to Step 2
 6-81
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.23 DTC 131304 Fuel Level Sensor Shorted to Ground

Step 2 Check whether the harness is shorted to ground

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Check the harness (# 930) between the controller (J2-30) and fuel level sensor for wear.
2. Disconnect the connectors from the fuel level sensor and the controller. Turn the multimeter to its
resistance function, and measure the resistance between the harness (# 930) sensor terminal and
the grounding (normally, >100kΩ).

Gray wire

Whether the harness is shorted to ground or not?

YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
6-82
6.4 Fault Code December 30, 2017
6.4.23 DTC 131304 Fuel Level Sensor Shorted to Ground CLG930E/936E

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the sensor connector and disconnect the controller connector. Turn the multimeter to its
resistance function, and measure the resistance between the J2-30 port and the grounding (normally,
>10Ω).
When the resistance is abnormal, this indicates there is an insulation fault in the connector
Whether the connector is faulty?
YES NO
Replace the connector.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-83
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.24 DTC 131317 Low fuel level

6.4.24 DTC 131317 Low fuel level System description

The fuel level sensor is a reed pipe type. The

DTC Description Consequence magnetic floater density is lower than the
working medium (diesel) density, so the fuel level
Low fuel level - When the
start switch is turned to sensor floats on the surface of the working
the ON position (without If the machine is medium and can slide up and down on the reed
starting the engine), the operated as pipe. When the floater moves on the reed pipe,
131317
signal circuit of the fuel usual, the engine the on-off of the internal circuit of the reed pipe is
level sensor detects that will shut down. controlled by a magnetic field to allow the
the fuel level is low resistance between the two output leads of the
(below 10%).
connector to change. Therefore, the fuel level
change is converted into a resistance signal
output, and through connecting to the controller
the fuel level in the tank is detected, and through
connecting to the display instrument the fuel
level is displayed.

LG922E930E06032

Fuel level sensor parameter table

Floater position Floater position

Output resistance Output resistance
(Refer to the place at (Refer to the place at
(Ω) (Ω)
17.5mm) 17.5mm)
Below L1 1100±11.0 L11-L12 550±5.5
L1-L2 1050±10.5 L12-L13 500±5.0
L2-L3 1000±10.0 L13-L14 450±4.5
L3-L4 950±9.5 L14-L15 400±4.0
L4-L5 900±9.0 L15-L16 350±3.5
L5-L6 850±8.5 L16-L17 300±3.0
L6-L7 800±8.0 L17-L18 250±2.5
L7-L8 750±7.5 L18-L19 200±2.0
L8-L9 700±7.0 L19-L20 150±1.5
L9-L10 650±6.5 L20-L21 100±1.0
L0-L11 600±6.0
6-84
6.4 Fault Code December 30, 2017
6.4.24 DTC 131317 Low fuel level CLG930E/936E

Oil level

Component location

Front

Fuel level sensor

 6-85
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.24 DTC 131317 Low fuel level

Fault diagnosis and troubleshooting steps

Step 1 Check whether the fuel level is low

Inspection method
Check the fuel level.
Whether the fuel level is too low or not?
YES NO
Add fuel.
Go to Step 3 Go to Step 2

Step 2 Check the level monitoring system for fault

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
If the fuel level is normal, check the fuel level monitoring system in accordance with the fault diagnosis
in the 131304- Fuel Level Sensor Shorted to the Ground.
Whether the level monitoring system fails?
YES NO
Repair or replace the fuel level sensor.
Go to Step 3 Go to Step 3

Step 3 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-86
6.4 Fault Code December 30, 2017
6.4.25 DTC 131603 Water-in-Fuel Sensor Voltage Above the Range Value CLG930E/936E

6.4.25 DTC 131603 Water-in-Fuel System description

Sensor Voltage Above the Range The water-in-fuel sensor is used to detect water
Value content in the fuel. The more the water in the
fuel, the smaller the resistance. Therefore, the
change in water content is converted into the
DTC Description Consequence resistance voltage signal output, and through
The water-in-fuel sensor connecting to the controller the water content in
voltage is below the the fuel is detected, and an alarm signal is sent.
range value. The signal
The engine can
131603 circuit of the water in the
not be started.
fuel sensor detects the
voltage is high (more
than 4.3V)

Component location

Front

Fuel-in-water
sensor
 6-87
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.25 DTC 131603 Water-in-Fuel Sensor Voltage Above the Range Value

Fault diagnosis and troubleshooting steps

Step 1 Check the water-in-fuel sensor for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position, and disconnect the connector from the water-in-fuel sensor:
1. Check the connector for looseness, rust, bending and damage.
2. Turn the multimeter to its resistance function, and measure the resistance between the water-in-fuel
sensor connector terminals 1 and 2 (normally, <4.6M/306.5K).
Whether the water-in-fuel sensor fails?
YES NO
Repair or replace the sensor.
Go to Step 4 Go to Step 2

Step 2 Check the harness for open-circuit

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Check the harness (# 921) and the grounding wire (# 254) between the controller (J2-21) and the
water-in-fuel sensor for wear.
2. Disconnect the connectors from the water-in-fuel sensor and the controller. Check the harness for
open-circuit:
(1) Turn the multimeter to its resistance function, and measure the resistance between the grounding
wire (#254) sensor terminal and the grounding (normally, <10Ω).
(2) Turn the multimeter to its resistance function, and measure the resistance of harness between the
connector terminals J2-21 and sensor (normally, <10Ω).
Is the harness open-circuit?
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
6-88
6.4 Fault Code December 30, 2017
6.4.25 DTC 131603 Water-in-Fuel Sensor Voltage Above the Range Value CLG930E/936E

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the water-in-fuel sensor connector and disconnect the controller connector. Turn the
multimeter to its resistance function, and measure the resistance between the harness at the controller
port J1 and the grounding (normally 2.62kΩ--4.6MΩ).
When the resistance is abnormal, this indicates the connector is poorly contacted.
Whether the connector is faulty?
YES NO
Replace the connector.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-89
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.26 DTC 131604 Water-in-Fuel Sensor Voltage Below the Range Value

6.4.26 DTC 131604 Water-in-Fuel System description

Sensor Voltage Below the Range The water-in-fuel sensor is used to detect water
Value content in the fuel. The more the water in the
fuel, the smaller the resistance. Therefore, the
change in water content is converted into the
DTC Description Consequence resistance voltage signal output, and through
The water-in-fuel sensor connecting to the controller the water content in
voltage is below the the fuel is detected, and an alarm signal is sent.
range value. The signal There is white
131604 circuit of the water-in-fuel smoke from the
sensor detects the power engine
voltage is low (below
0.25V).

Component location

Front

Fuel-in-water
sensor
6-90
6.4 Fault Code December 30, 2017
6.4.26 DTC 131604 Water-in-Fuel Sensor Voltage Below the Range Value CLG930E/936E

Fault diagnosis and troubleshooting steps

Step 1 Check the water-in-fuel sensor for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position, and disconnect the connector from the water-in-fuel sensor:
1. Check the connector for looseness, rust, bending and damage.
2. Turn the multimeter to its resistance function, and measure the resistance between the water-in-fuel
sensor connector terminals 1 and 2 (normally, >2.62K).
Whether the water-in-fuel sensor fails?
YES NO
Repair or replace the sensor.
Go to Step 4 Go to Step 2

Step 2 Check whether the harness is shorted to ground

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Check the harness (# 921) between the controller (J2-21) and the water in fuel sensor for wear.
2. Disconnect the connectors from the water in fuel sensor and the controller, respectively. Turn the
multimeter to its resistance function, and measure the resistance between the harness (# 921)
sensor terminal and the grounding (normally, >100K).
Whether the harness is shorted to ground or not?
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
 6-91
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.26 DTC 131604 Water-in-Fuel Sensor Voltage Below the Range Value

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the water-in-fuel sensor connector and disconnect the controller connector. Turn the
multimeter to its resistance function, and measure the resistance between the controller port J2-21 and
the grounding (normally, >2.62kΩ).
When the resistance is abnormal, this indicates there is an insulation fault in the connector
Whether the connector is faulty?
YES NO
Replace the connector.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-92
6.4 Fault Code December 30, 2017
6.4.27 DTC 131605 Water-in-fuel Sensor Open-circuit CLG930E/936E

6.4.27 DTC 131605 Water-in-fuel System description

Sensor Open-circuit The water-in-fuel sensor is used to detect water
content in the fuel. The more the water in the
fuel, the smaller the resistance. Therefore, the
DTC Description Consequence
change in water content is converted into the
The water-in-fuel sensor resistance voltage signal output, and through
is open-circuit (The connecting to the controller the water content in
131605 signal circuit of the
the fuel is detected, and an alarm signal is sent.
water-in-fuel sensor is
open-circuit)

Component location

Front

Fuel-in-water
sensor
 6-93
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.27 DTC 131605 Water-in-fuel Sensor Open-circuit

Fault diagnosis and troubleshooting steps

Step 1 Check the water-in-fuel sensor for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position, and disconnect the connector from the water-in-fuel sensor:
1. Check the connector for looseness, rust, bending and damage.
2. Turn the multimeter to its resistance function, and measure the resistance between the water-in-fuel
sensor connector terminals 1 and 2 (normally, <4.6M).
Whether the water-in-fuel sensor fails?
YES NO
Repair or replace the sensor.
Go to Step 4 Go to Step 2

Step 2 Check the harness for open-circuit

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Check the harness (# 921) and the grounding wire (# 254) between the controller (J2-21) and the
water-in-fuel sensor for wear.
2. Disconnect the connectors from the water-in-fuel sensor and the controller. Check the harness for
open-circuit:
(1) Turn the multimeter to its resistance function, and measure the resistance between the grounding
wire (#254) sensor terminal and the grounding (normally, <10Ω).
(2) Turn the multimeter to its resistance function, and measure the resistance of harness between the
connector terminals J2-21 and sensor (normally, <10Ω).
Is the harness open-circuit?
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
6-94
6.4 Fault Code December 30, 2017
6.4.27 DTC 131605 Water-in-fuel Sensor Open-circuit CLG930E/936E

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the water-in-fuel sensor connector and disconnect the controller connector. Turn the
multimeter to its resistance function, and measure the resistance between the harness at the controller
port J2-21 and the grounding (normally, <4.6M).
When the resistance is abnormal, this indicates the connector is poorly contacted.
Whether the connector is faulty?
YES NO
Replace the connector.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-95
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.28 DTC 131615 Water-in-fuel

6.4.28 DTC 131615 Water-in-fuel System description

The water-in-fuel sensor is used to detect water

DTC Description Consequence content in the fuel. The more the water in the
fuel, the smaller the resistance. Therefore, the
Water in fuel-When the
start switch is turned to change in water content is converted into the
If the machine is resistance voltage signal output, and through
the ON position (without
operated as connecting to the controller the water content in
starting the engine), the
131615 usual, the engine
signal circuit of the the fuel is detected, and an alarm signal is sent.
power will
water-in-fuel sensor
reduce.
detects there is water in
the fuel.

Component location

Front

Fuel-in-water
sensor
6-96
6.4 Fault Code December 30, 2017
6.4.28 DTC 131615 Water-in-fuel CLG930E/936E

Fault diagnosis and troubleshooting steps

Step 1 Check the fuel for water.

Inspection method
Check the fuel-water separator for water.
Whether water in the fuel or not?
YES NO
Drain the water in the fuel.
Go to Step 3 Go to Step 2

Step 2 Check the water-in-fuel monitoring system for fault.

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
If the fuel is normal, check the water-in-fuel detection circuit or the water-in-fuel sensor for fault in
accordance with the fault diagnosis in the 131604- Water-in-Fuel Sensor Voltage below the Range
Value or 131603- Water-in-Fuel Sensor Voltage above the Range Value.
Whether the water-in-fuel monitoring system fails?
YES NO
Repair the water-in-fuel detection circuit or replace
the water-in-fuel sensor.
Go to Step 3 Go to Step 3

Step 3 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-97
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.29 DTC 131703 Sensor Power (5V) Shorted to the Battery

6.4.29 DTC 131703 Sensor Power System description

(5V) Shorted to the Battery The accelerator control system mainly consists
of the accelerator potentiometer (accelerator
knob), controller and accelerator actuator. The
DTC Description Consequence
schematic diagram is shown below: #907 and
The accelerator #904 are drive control lines. The controller is
The sensor power (5V) is
131703 actuator cannot driven by 2 pins. If either pin is open-circuit, this
shorted to the battery.
function properly.
can cause the accelerator system fault. The
accelerator potentiometer is used to control the
engine speed. As shown in the figure, Pin 1 of
the R1 connector is connected to the 5V power,
Pin 2 is connected to the controller-sensor
ground terminal and Pin 3 is connected to the
accelerator signal feedback terminal. The
accelerator actuator controls the engine
accelerator opening through the flexible shaft to
control the engine speed. The terminals are
shown in the figure. Pin 3 of the M1 connector is
the controller power (5V), pin 5 is grounded, pin
2 is used for the accelerator feedback signal, pin
1 is used to control the accelerator motor’s
forward rotation and pin 4 is used to control the
accelerator motor’s reverse rotation.
6-98
6.4 Fault Code December 30, 2017
6.4.29 DTC 131703 Sensor Power (5V) Shorted to the Battery CLG930E/936E

Component location

Front

Accelerator
potentiometer

Accelerator actuator

Controller
LG925E4F06193

P1 Pump
pressure
sensor
P2Pump
pressure
sensor

Front

LG925E4F06176
 6-99
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.29 DTC 131703 Sensor Power (5V) Shorted to the Battery

Fault diagnosis and troubleshooting steps

Step 1 Check the sensor power (5V) is shorted to the battery.

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
Turn the start switch to the ON position and disconnect the controller connector to switch on the
switches of all electrical equipment, and then measure the voltage between the J1-28 port (# 828) and
ground (normally, 0V).
Whether the sensor power (5V) is shorted to the battery or not?
YES NO
Re-connect the harness and wrap it or replace the
connector.
Go to Step 2 Go to Step 2

Step 2 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-100
6.4 Fault Code December 30, 2017
6.4.30 DTC 131704 Sensor Power (5V) Shorted to the Ground CLG930E/936E

6.4.30 DTC 131704 Sensor Power System description

(5V) Shorted to the Ground The accelerator control system mainly consists
of the accelerator potentiometer (accelerator
knob), controller and accelerator actuator. The
DTC Description Consequence
schematic diagram is shown below: #907 and
The accelerator #904 are drive control lines. The controller is
The sensor power (5V) is
131704 actuator cannot driven by 2 pins. If either pin is open-circuit, this
shorted to ground
function properly.
can cause the accelerator system fault. The
accelerator potentiometer is used to control the
engine speed. As shown in the figure, Pin 1 of
the R1 connector is connected to the 5V power,
Pin 2 is connected to the controller-sensor
ground terminal and Pin 3 is connected to the
accelerator signal feedback terminal. The
accelerator actuator controls the engine
accelerator opening through the flexible shaft to
control the engine speed. The terminals are
shown in the figure. Pin 3 of the M1 connector is
the controller power (5V), pin 5 is grounded, pin
2 is used for the accelerator feedback signal, pin
1 is used to control the accelerator motor’s
forward rotation and pin 4 is used to control the
accelerator motor’s reverse rotation.
 6-101
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.30 DTC 131704 Sensor Power (5V) Shorted to the Ground

Component location

Front

Accelerator
potentiometer

Accelerator actuator

Controller
LG925E4F06193

P1 Pump
pressure
sensor
P2Pump
pressure
sensor

Front

LG925E4F06176
6-102
6.4 Fault Code December 30, 2017
6.4.30 DTC 131704 Sensor Power (5V) Shorted to the Ground CLG930E/936E

Fault diagnosis and troubleshooting steps

Step 1 Check the accelerator knob or actuator for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position and disconnect the connectors from the accelerator knob and
actuator:
1. Check the connector for moisture, oil dirt and other
2. Turn the multimeter to its resistance function, and measure the resistance between the accelerator
knob connector terminals 1 and 2 (normally, >10Ω).
3. Measure the resistance between the terminals 3 and 5 of the accelerator actuator connector
(normally, >10Ω).
Whether the accelerator knob or actuator fails?
YES NO
Repair or replace the accelerator knob and the
accelerator actuator.
Go to Step 4 Go to Step 2

Step 2 Check whether the harness is shorted to ground

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Check the harnesses (# 828 and # 922) between the controllers (J1-28 and J2-22) and accelerator
knob, accelerator actuator, hoist overload pressure sensor, P1 pump pressure sensor, P2 pump
pressure sensor, N2 pump pressure sensor, N1 pump pressure sensor for wear, respectively.
2. Disconnect the accelerator knob, the accelerator actuator connector and the controller connector.
Turn the multimeter to its resistance function, and measure the resistance between the terminal
opposite to the harness (# 828/# 922) controller and the grounding, respectively (normally, >100K).
Whether the harness is shorted to ground or not?
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
 6-103
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.30 DTC 131704 Sensor Power (5V) Shorted to the Ground

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
1. Connect the accelerator knob connector, and disconnect connector from the pump pressure sensor
and the controller connector, turn the multimeter to its resistance function, and measure the
resistance between the controller ports J1-28 and J1-22(normally, >10Ω).
2. Connect the pump pressure sensor connector and disconnect the accelerator knob and the
controller connector. Turn the multimeter to its resistance function, and measure the resistance
between the controller port J1-28 and J-22 (normally, >10Ω).
When the resistance in any step above is abnormal, this indicates an insulation fault develops in the
connector.
Whether the connector is faulty?
YES NO
Replace the connector.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-104
6.4 Fault Code December 30, 2017
6.4.31 DTC 141105 Pump Proportional Solenoid Valve Feedback Open-Circuited CLG930E/936E

6.4.31 DTC 141105 Pump System description

Proportional Solenoid Valve The pilot pump provides oil to the
Feedback Open-Circuited electromagnetic proportional pressure-reducing
valve on the main pump directly. The
electromagnetic proportional pressure-reducing
DTC Description Consequence valve regulates the displacement of the main
Pump proportional The complete pump based on various operating conditions.
141005 solenoid valve feedback machine moves
open-circuit slowly.

Component location

Front

Pump proportional
solenoid valve
 6-105
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.31 DTC 141105 Pump Proportional Solenoid Valve Feedback Open-Circuited

Fault diagnosis and troubleshooting steps

Step 1 Check the pump proportional solenoid valve for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position and disconnect the pump proportional solenoid valve
connector
1. Check the connector for moisture, oil dirt and other
2. Turn the multimeter to its resistance function, and measure the resistance between the pump
proportional solenoid valve connector terminals 1 and 2 (normally, 16~40Ω).
Whether the pump proportional solenoid valve fails?
YES NO
Repair or replace the pump proportional solenoid
valve.
Go to Step 4 Go to Step 2

Step 2 Check the harness for open-circuit

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Check the harness (No. 905/No. 901) between the controller and the pump proportional solenoid
valve for wear.
2. Disconnect the connectors from the pump proportional solenoid valve and the controller,
respectively. Turn the multimeter to its resistance function, and measure the resistance of the
harness (# 905/# 901) between the controller and the solenoid valve, respectively (normally, <10Ω).
Is the harness open-circuit?
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
6-106
6.4 Fault Code December 30, 2017
6.4.31 DTC 141105 Pump Proportional Solenoid Valve Feedback Open-Circuited CLG930E/936E

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the pump proportional solenoid valve connector and disconnect the controller connector. Turn
the multimeter to its resistance function, and measure the resistance between the controller ports J2-01
and J2-05 (normally, 16~40Ω).
When the resistance is abnormal, this indicates the connector is poorly contacted.
Whether the connector is faulty?
YES NO
Replace the connector.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-107
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.32 DTC 141006 Pump Proportional Solenoid Valve Feedback Overcurrent

6.4.32 DTC 141006 Pump

Proportional Solenoid Valve System description
Feedback Overcurrent
The pilot pump provides oil to the
electromagnetic proportional pressure-reducing
DTC Description Consequence valve on the main pump directly. The
The engine gets
electromagnetic proportional pressure-reducing
Pump proportional valve regulates the displacement of the main
stuck or even
141006 solenoid valve feedback pump based on various operating conditions.
shuts down in a
overcurrent
low gear.

Component location

Front

Pump proportional
solenoid valve
6-108
6.4 Fault Code December 30, 2017
6.4.32 DTC 141006 Pump Proportional Solenoid Valve Feedback Overcurrent CLG930E/936E

Fault diagnosis and troubleshooting steps

Step 1 Check the pump proportional solenoid valve for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position and disconnect the pump proportional solenoid valve
connector
1. Check the connector for moisture, oil dirt and other
2. Turn the multimeter to its resistance function, and measure the resistance between the pump
proportional solenoid valve connector terminals 1 and 2 (normally, 16~40Ω).
Whether the pump proportional solenoid valve fails?
YES NO
Repair or replace the pump proportional solenoid
valve.
Go to Step 4 Go to Step 2

Step 2 Check the harness for short-circuit

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Check the harnesses (# 901 and # 905) between the controller (J2-01 and J2-05 ) and the pump
proportional solenoid valve for wear.
Disconnect both the controller and the solenoid valve
2. Check the two harnesses for short-circuit: Turn the multimeter to its resistance function, and
measure the resistance of the harness (# 901 and # 905) between the solenoid valve terminals
(normally, >100kΩ).
3. Check whether the harness is shorted to the battery. Turn the start switch to the ON position and
switch on the switches of all electrical equipment, and then measure the voltage between the
harness (# 901/# 905) solenoid valve terminal and the grounding (normally, 0V).
Is the harness short-circuit?
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
 6-109
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.32 DTC 141006 Pump Proportional Solenoid Valve Feedback Overcurrent

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the pump proportional solenoid valve connector and disconnect the controller connector. Turn
the multimeter to its resistance function, and measure the resistance between the controller ports J2-01
and J2-05 (normally, 16~40Ω).
When the resistance is abnormal, this indicates there is an insulation fault in the connector
Whether the connector is faulty?
YES NO
Replace the connector.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-110
6.4 Fault Code December 30, 2017
6.4.33 DTC 141104 Pump Proportional Solenoid Valve Shorted to Ground CLG930E/936E

6.4.33 DTC 141104 Pump

Proportional Solenoid Valve System description
Shorted to Ground
The pilot pump provides oil to the
electromagnetic proportional pressure-reducing
DTC Description Consequence valve on the main pump directly. The
Pump proportional
electromagnetic proportional pressure-reducing
141104 solenoid valve shorted to Works slowly valve regulates the displacement of the main
ground pump based on various operating conditions.

Component location

Front

Pump proportional
solenoid valve
 6-111
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.33 DTC 141104 Pump Proportional Solenoid Valve Shorted to Ground

Fault diagnosis and troubleshooting steps

Step 1 Check the pump proportional solenoid valve for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position and disconnect the pump proportional solenoid valve
connector
1. Check the connector for moisture, oil dirt and other
2. Turn the multimeter to its resistance function, and measure the resistance between the pump
proportional solenoid valve connector terminals 1 and 2 (normally, 16~40Ω).
Whether the pump proportional solenoid valve fails?
YES NO
Repair or replace the pump proportional solenoid
valve.
Go to Step 4 Go to Step 2

Step 2 Check whether the harness is shorted to ground

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Check the harnesses (# 901 and # 905) between the controller (J2-01 and J2-05 ) and the pump
proportional solenoid valve for wear.
2. Disconnect the connectors from the pump proportional solenoid and the controller. Turn the
multimeter to its resistance function, and measure the resistance between the harnesses (No. 904
and No. 905) solenoid valve terminal and the grounding, respectively (normally, >100kΩ)
Whether the harness is shorted to ground or not?
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
6-112
6.4 Fault Code December 30, 2017
6.4.33 DTC 141104 Pump Proportional Solenoid Valve Shorted to Ground CLG930E/936E

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the pump proportional solenoid valve connector and disconnect the controller connector. Turn
the multimeter to its resistance function, and measure the resistance between the controller port J2-01
and the grounding (normally 16~40Ω).
When the resistance is abnormal, this indicates there is an insulation fault in the connector
Whether the connector is faulty?
YES NO
Replace the connector.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-113
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.34 DTC 141105 Pump Proportional Solenoid Valve Feedback Open-circuited

6.4.34 DTC 141105 Pump System description

Proportional Solenoid Valve The pilot pump provides oil to the
Feedback Open-circuited electromagnetic proportional pressure-reducing
valve on the main pump directly. The
electromagnetic proportional pressure-reducing
DTC Description Consequence valve regulates the displacement of the main
Pump proportional pump based on various operating conditions.
solenoid valve open- The engine gets
141105
circuited or shorted to stuck
the battery

Component location

Front

Pump proportional
solenoid valve
6-114
6.4 Fault Code December 30, 2017
6.4.34 DTC 141105 Pump Proportional Solenoid Valve Feedback Open-circuited CLG930E/936E

Fault diagnosis and troubleshooting steps

Step 1 Check the pump proportional solenoid valve for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position and disconnect the pump proportional solenoid valve
connector
1. Check the connector for moisture, oil dirt and other
2. Turn the multimeter to its resistance function, and measure the resistance between the pump
proportional solenoid valve connector terminals 1 and 2 (normally, 16~40Ω).
Whether the pump proportional solenoid valve fails?
YES NO
Repair or replace the pump proportional solenoid
valve.
Go to Step 4 Go to Step 2

Step 2 Check whether the harness is open-circuited or shorted to the battery.

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Check the harness (No. 905/No. 901) between the controller and the pump proportional solenoid
valve for wear.
2. Disconnect the connectors from the pump proportional solenoid valve and the controller.
3. Check whether the harness is shorted to the battery. Turn the start switch to the ON position and
switch on the switches of all electrical equipment, and then measure the voltage between the
harness (# 901/# 905) solenoid valve terminal and the grounding (normally, 0V).
4. Check the harnesses for open-circuit. Turn the multimeter to its resistance function, and measure
the resistance of the harnesses (#905 and #901) between the controller and the solenoid valve,
respectively (normally,<10Ω).
Whether the harness open-circuited or shorted to the battery or not?
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
 6-115
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.34 DTC 141105 Pump Proportional Solenoid Valve Feedback Open-circuited

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the pump proportional solenoid valve connector and disconnect the controller connector. Turn
the multimeter to its resistance function, and measure the resistance between the controller ports J2-01
and J2-05 (normally, 16~40Ω).
When the resistance is abnormal, this indicates the connector is poorly contacted.
Whether the connector is faulty?
YES NO
Replace the connector.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-116
6.4 Fault Code December 30, 2017
6.4.35 DTC 151004 Attachment Confluence Solenoid Valve Shorted to Ground CLG930E/936E

6.4.35 DTC 151004 Attachment

Confluence Solenoid Valve
Shorted to Ground System description

The attachment confluence solenoid valve

DTC Description Consequence
(hydraulic shear function solenoid valve, ATT
Attachment confluence There is no function solenoid valve) (optional) is used to
151004 solenoid valve shorted to hydraulic shear control realization of hydraulic shear function.
ground function

Component location

Front

Attachment
confluent solenoid
valve (position)
 6-117
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.35 DTC 151004 Attachment Confluence Solenoid Valve Shorted to Ground

Fault diagnosis and troubleshooting steps

Step 1 Check the attachment confluence solenoid valve for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position and disconnect the attachment confluence solenoid valve
connector
1. Check the connector for moisture, oil dirt and other
2. Turn the multimeter to its resistance function, and measure the resistance between the attachment
confluence solenoid connector terminals 1 and 2 (normally, 16~40Ω).
Whether the attachment confluence solenoid valve fails?
YES NO
Repair or replace the attachment confluence
solenoid valve.
Go to Step 4 Go to Step 2

Step 2 Check whether the harness is shorted to ground

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Check the harness (No. 912) between the controller (J2-12) and the attachment confluent solenoid
valve for wear.
2. Disconnect the attachment confluence solenoid valve connector and the controller connector. Turn
the multimeter to its resistance function, and measure the resistance between the harness (# 912)
solenoid valve terminal and the grounding (normally, >100kΩ)
Whether the harness is shorted to ground or not?
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
6-118
6.4 Fault Code December 30, 2017
6.4.35 DTC 151004 Attachment Confluence Solenoid Valve Shorted to Ground CLG930E/936E

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the attachment confluent solenoid valve connector and disconnect the controller connector.
Turn the multimeter to its resistance function, and measure the resistance between the harness at
controller port J2-12 and the grounding (normally, 16~40Ω).
When the resistance is abnormal, this indicates there is an insulation fault in the connector
Whether the connector is faulty?
YES NO
Replace the connector.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-119
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.36 DTC 151005 Attachment Confluent Solenoid Valve Open-circuited or Shorted to the

6.4.36 DTC 151005 Attachment System description

Confluent Solenoid Valve Open- The attachment confluence solenoid valve
circuited or Shorted to the Battery (hydraulic shear function solenoid valve, ATT
function solenoid valve) (optional) is used to
control realization of hydraulic shear function.
DTC Description Consequence
Attachment confluent
There is no
solenoid valve open-
151005 hydraulic shear
circuited or shorted to
function
the battery

Component location

Front

Attachment
confluent solenoid
valve (position)
6-120
6.4 Fault Code December 30, 2017
6.4.36 DTC 151005 Attachment Confluent Solenoid Valve Open-circuited or Shorted to the BatteryCLG930E/

Fault diagnosis and troubleshooting steps

Step 1 Check the attachment confluence solenoid valve for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position and disconnect the attachment confluence solenoid valve
connector
1. Check the connector for moisture, oil dirt and other
2. Turn the multimeter to its resistance function, and measure the resistance between the attachment
confluence solenoid connector terminals 1 and 2 (normally, 16~40Ω).
Whether the attachment confluence solenoid valve fails?
YES NO
Repair or replace the attachment confluence
solenoid valve.
Go to Step 4 Go to Step 2

Step 2 Check whether the harness is open-circuited or shorted to the battery.

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Check whether the harness (# 912) or the grounding wire between the controller and the
attachment confluence solenoid valve is worn.
Disconnect the attachment confluence solenoid valve connector and the controller connector
2. Check whether the harness is shorted to the battery. Turn the start switch to the ON position and
turn on all switches of the electrical equipment, and then measure the voltage between the harness
(No.912) solenoid valve terminal and the grounding (normally, 0V)
3. Check the harness for open-circuit. Turn the multimeter to its resistance function, and measure the
resistance of the harness (#912) between the controller and the solenoid valve and that of the
harness between the solenoid valve and the grounding, respectively (normally, <10Ω).
The harness is open-circuited or shorted to the battery or not?
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
 6-121
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.36 DTC 151005 Attachment Confluent Solenoid Valve Open-circuited or Shorted to the

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the attachment confluent solenoid valve connector and disconnect the controller connector.
Turn the multimeter to its resistance function, and measure the resistance between the harness at
controller port J2-12 and the grounding (normally, 16~40Ω).
When the resistance is abnormal, this indicates the connector is poorly contacted.
Whether the connector is faulty?
YES NO
Replace the connector.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-122
6.4 Fault Code December 30, 2017
6.4.37 DTC 151204 A2 Travel Speed Solenoid Shorted to Ground CLG930E/936E

6.4.37 DTC 151204 A2 Travel System description

Speed Solenoid Shorted to The controller outputs a signal to the travel shift
Ground solenoid valve through the harness (# 910) to
open the valve port.

DTC Description Consequence

The travel shift solenoid There is no
151204 valve is shorted to travel shift
ground. function.

Component location Attached drawing

Front
Controller

A2-marked solenoid
valve can be located.

Controller connector
Front
 6-123
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.37 DTC 151204 A2 Travel Speed Solenoid Shorted to Ground

Fault diagnosis and troubleshooting steps

Step 1 Check the travel proportional solenoid valve for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position and disconnect the connector from the travel speed solenoid
valve.
1. Check the connector for looseness, rust, bending and damage.
2. Measure the resistance between both ends of the travel shift solenoid valve (normally,16~40Ω )
Whether the travel shift solenoid valve fails?
YES NO
Repair or replace the travel shift solenoid valve.
Go to Step 4 Go to Step 2

Step 2 Check whether the power harness of the travel shift solenoid valve is shorted to ground

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Turn the start switch to the OFF position for fault diagnosis.
2. Disconnect the connectors between the controller (in the attached drawing) and travel shift solenoid
valve, and measure the resistance between the power line (# 910) of travel shift solenoid valve and
the grounding. The resistance should be greater than 100kΩ
Whether the power harness of the travel shift solenoid valve is shorted to ground or not?
YES NO
Connect the harness again and wrap the harness.
Go to Step 4 Go to Step 3
6-124
6.4 Fault Code December 30, 2017
6.4.37 DTC 151204 A2 Travel Speed Solenoid Shorted to Ground CLG930E/936E

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the travel shift solenoid valve connector and disconnect the controller connector. Turn the
multimeter to its resistance function, and measure the resistance between the harness at the controller
port J2-10 and the grounding (normally, 16-40Ω). When the resistance is abnormal, this indicates there
is a fault in the connector.

Definition of
connector pin
serial number

Whether the connector is faulty?

YES NO
Replace the connector.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-125
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.38 DTC 151205 A2 Travel Shift Solenoid Valve Open-Circuited or Shorted to the Battery

6.4.38 DTC 151205 A2 Travel Shift System description

Solenoid Valve Open-Circuited or The controller outputs a signal to the travel shift
Shorted to the Battery solenoid valve through the harness (# 910) to
open the valve port.

DTC Description Consequence

There is no
travel shift
A2 travel shift solenoid function or the
151205 valve is open-circuited or travel shift
shorted to the battery. solenoid valve is
uncontrolled by
the controller.

Component location Attached drawing

Front
Controller

A2-marked solenoid
valve can be located.

Controller connector
Front
6-126
6.4 Fault Code December 30, 2017
6.4.38 DTC 151205 A2 Travel Shift Solenoid Valve Open-Circuited or Shorted to the Battery CLG930E/936E

Fault diagnosis and troubleshooting steps

Step 1 Check the travel shift solenoid valve for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position and disconnect the connector from the travel speed solenoid
valve.
1. Check the connector for looseness, rust, bending and damage.
2. Measure the resistance between both ends of the travel shift solenoid valve (normally,16~40Ω ).
Whether the travel shift solenoid valve fails?
YES NO
Repair or replace the travel proportional solenoid
valve.
Go to Step 5 Go to Step 2

Step 2 Check whether the power harness of the travel shift solenoid valve is shorted to ground

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Turn the start switch to the OFF position for fault diagnosis.
2. Disconnect the connectors between the controller (in the attached drawing) and travel shift solenoid
valve, and measure the resistance between the power line (# 910) of travel shift solenoid valve and
the grounding. The resistance should be greater than 100kΩ
Whether the power harness of the travel shift solenoid valve is shorted to ground or not?
YES NO
Connect the harness again and wrap the harness.
Go to Step 5 Go to Step 3
 6-127
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.38 DTC 151205 A2 Travel Shift Solenoid Valve Open-Circuited or Shorted to the Battery

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the travel shift solenoid valve connector and disconnect the controller connector. Turn the
multimeter to its resistance function, and measure the resistance between the harness at the controller
port J2-10 and the grounding (normally, 16-40Ω). When the resistance is abnormal, this indicates there
is a fault in the connector.

Definition of
connector pin
serial number

Whether the connector is faulty?

YES NO
Replace the connector.
Go to Step 5 Go to Step 4

Step 4 Check whether the travel speed solenoid valve is shorted to the battery

Inspection method
Turn the start switch to the ON position for fault diagnosis.
Disconnect the connectors from the controller and A2 travel shift solenoid valve to switch on the
switches of all electrical equipment, and then measure the voltage of the harness of A2 travel shift
solenoid valve. The voltage should be 0.
Whether the travel speed solenoid valve is shorted to the battery or not?
YES NO
Repair or replace the travel shift solenoid valve.
Go to Step 5 Go to Step 2
6-128
6.4 Fault Code December 30, 2017
6.4.38 DTC 151205 A2 Travel Shift Solenoid Valve Open-Circuited or Shorted to the Battery CLG930E/936E

Step 5 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-129
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.39 DTC 151304 A3 Flattening Solenoid Valve Shorted to Ground

6.4.39 DTC 151304 A3 Flattening Flattening solenoid valve

There is no
151304 flattening
Solenoid Valve Shorted to Ground shorted to ground.
function.

DTC Description Consequence

System description

The controller outputs a signal to the flattening

Component location Attached drawing

Front
Controller
A3-marked solenoid
valve can be located.

Controller connector
Front
6-130
6.4 Fault Code December 30, 2017
6.4.39 DTC 151304 A3 Flattening Solenoid Valve Shorted to Ground CLG930E/936E

Fault diagnosis and troubleshooting steps

Step 1 Check the flattening solenoid valve for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position and disconnect the connector from the flattening solenoid
valve:
1. Check the connector for looseness, rust, bending and damage.
2. Measure the resistance between the both ends of the flattening solenoid valve. The resistance
should be 16~40Ω.
Whether the flattening solenoid valve fails?
YES NO
Repair or replace the flattening solenoid valve.
Go to Step 4 Go to Step 2

Step 2 Check whether the power line of the flattening solenoid valve is shorted to ground

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Turn the start switch to the OFF position for fault diagnosis
2. Disconnect the connectors from the controller (attached drawing) and the flattening solenoid valve,
and measure the resistance between the power line (# 827) of the flattening solenoid valve and the
grounding. The resistance should be greater than 100kΩ.
Whether the power line of the flattening solenoid valve is shorted to ground or not?
YES NO
Connect the harness again and wrap the harness.
Go to Step 4 Go to Step 3
 6-131
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.39 DTC 151304 A3 Flattening Solenoid Valve Shorted to Ground

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the flattening solenoid valve connector and disconnect the controller connector. Turn the
multimeter to its resistance function, and measure the resistance between the harness (# 827) at the
controller port J1-27 and the grounding (normally, 16-40Ω). When the resistance is abnormal, this
indicates there is a fault in the connector.

Definition of
connector pin
serial number

Whether the connector is faulty?

YES NO
Replace the connector.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-132
6.4 Fault Code December 30, 2017
6.4.40 Fault Code 151305 A3 Flattening Solenoid Valve Open-Circuited or Shorted to the Battery CLG930E/

6.4.40 Fault Code 151305 A3 System description

Flattening Solenoid Valve Open- The controller outputs a signal to the flattening
Circuited or Shorted to the solenoid valve through the harness (# 827) to
open the valve port.
Battery

DTC Description Consequence

There is no
A3 Flattening solenoid flattening function
valve is open-circuited or the flattening
151305
or shorted to the solenoid valve is
battery. uncontrolled by the
controller.

Component location Attached drawing

Front
Controller
A3-marked solenoid
valve can be located.

Controller connector
Front
 6-133
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.40 Fault Code 151305 A3 Flattening Solenoid Valve Open-Circuited or Shorted to the

Fault diagnosis and troubleshooting steps

Step 1 Check the flattening solenoid valve for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position and disconnect the connector from the flattening solenoid
valve:
1. Check the connector for looseness, rust, bending and damage.
2. Measure the resistance between the both ends of the flattening solenoid valve(normally, 16~40Ω).
Whether the flattening solenoid valve fails?
YES NO
Repair or replace the flattening solenoid valve.
Go to Step 5 Go to Step 2

Step 2 Check the harness for open-circuit

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
6-134
6.4 Fault Code December 30, 2017
6.4.40 Fault Code 151305 A3 Flattening Solenoid Valve Open-Circuited or Shorted to the Battery CLG930E/

Inspection method
1. Check the harness (No. 827) and the grounding wire (No. 222) between the controller (J1-27) and
the flattening solenoid valve for wear.
2. Disconnect the connectors from the flattening solenoid valve and the controller. Check the harness
for open-circuit:
(1) Turn the multimeter to its resistance function, and measure the resistance between the connector
terminals J1-27 and flattening solenoid valve harness (normally, <10Ω).
(2) Turn the multimeter to its resistance function, and measure the resistance between the flattening
solenoid valve connecting terminal and the grounding wire (normally, <10Ω).

Definition of
connector pin
serial number

Is the harness open-circuit?

YES NO
Connect the harness again and wrap the harness.
Go to Step 5 Go to Step 3
 6-135
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.40 Fault Code 151305 A3 Flattening Solenoid Valve Open-Circuited or Shorted to the

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the flattening solenoid valve connector and disconnect the controller connector. Turn the
multimeter to its resistance function, and measure the resistance between the harness at the controller
port J1-27 and the grounding (normally, 16-40Ω). When the resistance is abnormal, this indicates there
is a fault in the connector.
Whether the connector is faulty?
YES NO
Replace the connector.
Go to Step 5 Go to Step 4

Step 4 Check whether the flattening solenoid valve is shorted to the battery

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the ON position for fault diagnosis.
Disconnect the connectors from the controller and A3 flattening solenoid valve to switch on the
switches of all electrical equipment, and then measure the voltage of the harness of A3 flattening
solenoid valve. The voltage should be 0V.
Whether the flattening solenoid valve is shorted to the battery or not?
YES NO
Find out the short circuit position and re-connect
the harness and wrap it
Go to Step 5 Go to Step 5

Step 5 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-136
6.4 Fault Code December 30, 2017
6.4.41 DTC 151404 A8 Trenching Solenoid Valve Shorted to the Ground CLG930E/936E

6.4.41 DTC 151404 A8 Trenching System description

Solenoid Valve Shorted to the The controller outputs a signal to the trenching
Ground solenoid valve A8 through the harness (# 825) to
open the valve port.

DTC Description Consequence

The digging solenoid
There is no
151404 valve is shorted to
digging function.
ground.

Component location Attached drawing

Front
Controller
A8-marked solenoid
valve can be located.

Controller connector
Front
 6-137
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.41 DTC 151404 A8 Trenching Solenoid Valve Shorted to the Ground

Fault diagnosis and troubleshooting steps

Step 1 Check the digging solenoid valve for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position and disconnect the connector from the digging solenoid valve.
1. Check the connector for looseness, rust, bending and damage.
2. Measure the resistance between both ends of the digging solenoid valve(normally,16~40Ω).
Whether the digging solenoid valve fails?
YES NO
Repair or replace the digging solenoid valve.
Go to Step 4 Go to Step 2

Step 2 Check whether the power line of the digging solenoid valve is shorted to ground

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Turn the start switch to the OFF position for fault diagnosis
2. Disconnect the connectors from the controller (attached drawing) and the trenching solenoid valve,
and measure the resistance between the power line (No. 825) of the trenching solenoid valve and
the grounding. The resistance should be normally more than100kΩ.
Whether the power harness of the digging solenoid valve is shorted to ground or not?
YES NO
Connect the harness again and wrap the harness.
Go to Step 4 Go to Step 3
6-138
6.4 Fault Code December 30, 2017
6.4.41 DTC 151404 A8 Trenching Solenoid Valve Shorted to the Ground CLG930E/936E

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the digging function solenoid valve connector and disconnect the controller connector. Turn
the multimeter to its resistance function, and measure the resistance between the harness (# 825) at
the controller port J1-25 and the grounding (normally, 16-40Ω). When the resistance is abnormal, this
indicates there is a fault in the connector.

Definition of
connector pin
serial number

Whether the connector is faulty?

YES NO
Replace the connector.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-139
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.42 DTC 151405 A8 Trenching Solenoid Valve Open-Circuited or Shorted to the Battery

6.4.42 DTC 151405 A8 Trenching System description

Solenoid Valve Open-Circuited or The controller outputs a signal to the trenching
Shorted to the Battery solenoid valve A8 through the harness (# 825) to
open the valve port.

DTC Description Consequence

There is no
The trenching solenoid digging function
151405 valve is open-circuited or or always in the
shorted to the battery. digging function
state.

Component location Attached drawing

Front
Controller
A8-marked solenoid
valve can be located.

Controller connector
Front
6-140
6.4 Fault Code December 30, 2017
6.4.42 DTC 151405 A8 Trenching Solenoid Valve Open-Circuited or Shorted to the Battery CLG930E/936E

Fault diagnosis and troubleshooting steps

Step 1 Check the digging solenoid valve for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position and disconnect the connector from the digging solenoid valve:
1. Check the connector for looseness, rust, bending and damage.
2. Measure the resistance between both ends of the digging solenoid valve(normally,16~40Ω).
Whether the digging solenoid valve fails?
YES NO
Repair or replace the digging solenoid valve.
Go to Step 5 Go to Step 2

Step 2 Check whether the power line of the digging solenoid valve is shorted to ground

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
 6-141
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.42 DTC 151405 A8 Trenching Solenoid Valve Open-Circuited or Shorted to the Battery

Inspection method
1. Check the connecting harness (No.825) and the earthing wire (No. 225) between the controller (J1-
25) (in the figure) and the trenching solenoid valve for wear.
2. Disconnect the connectors from the digging solenoid valve and the controller, and check the
harness for open-circuit:
(1) Turn the multimeter to its resistance function, and measure the resistance between the controller
port J1-25 and trenching solenoid valve harness (normally, <10Ω).
(2) Turn the multimeter to its resistance function, and measure the resistance between the grounding
wire (#225) trenching solenoid valve terminal and the grounding (normally, <10Ω).

Definition of
connector pin
serial number

Whether the power harness of the digging solenoid valve is shorted to ground or not?
YES NO
Connect the harness again and wrap the harness.
Go to Step 5 Go to Step 3
6-142
6.4 Fault Code December 30, 2017
6.4.42 DTC 151405 A8 Trenching Solenoid Valve Open-Circuited or Shorted to the Battery CLG930E/936E

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the digging function solenoid valve connector and disconnect the controller connector. Turn
the multimeter to its resistance function, and measure the resistance between the harness (# 825) at
the controller port J1-25 and the grounding (normally, 16-40Ω). When the resistance is abnormal, this
indicates there is a fault in the connector.
Whether the connector is faulty?
YES NO
Replace the connector.
Go to Step 5 Go to Step 4

Step 4 Check whether the trenching function solenoid valve is shorted to the battery

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the ON position for fault diagnosis.
Disconnect the connectors from the controller and A8 digging solenoid valve to switch on the switches
of all electrical equipment, and then measure the voltage of the harness of A8 digging solenoid valve.
The voltage should be 0V.
Whether the trenching solenoid valve is shorted to the battery or not?
YES NO
Find out the short circuit position and re-connect
the harness and wrap it
Go to Step 5 Go to Step 5

Step 5 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-143
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.43 DTC 151504 A5 Flow Adjusting Solenoid Shorted to Ground

6.4.43 DTC 151504 A5 Flow System description

Adjusting Solenoid Shorted to The controller outputs a signal to the flow
Ground adjusting solenoid valve through the harness
(No. 908) which feeds back the valve port
opening through the harness (No. 924). The
DTC Description Consequence controller performs logical judgement and then
A5 flow adjusting adjusts the signal to control the valve port
151504 solenoid is shorted to Flow adjustment opening through the harness (No. 908).
ground.

Component location Attached drawing

Front
Controller
A5-marked solenoid
valve can be located.

Controller connector
Front
6-144
6.4 Fault Code December 30, 2017
6.4.43 DTC 151504 A5 Flow Adjusting Solenoid Shorted to Ground CLG930E/936E

Fault diagnosis and troubleshooting steps

Step 1 Check the flow adjusting solenoid valve for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position, and disconnect the connector from the flow adjusting solenoid
valve.
1. Check the connector for looseness, rust, bending and damage.
2. Measure the resistance between both ends of the A5 flow adjusting solenoid valve (normally16-
40Ω).
Whether the flow adjusting valve fails?
YES NO
Repair or replace the flow adjusting solenoid valve.
Go to Step 2
Go to Step 4

Step 2 Check whether the power harness of flow adjusting solenoid valve is shorted to ground

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Turn the start switch to the OFF position for fault diagnosis
2. Disconnect the connectors from the controller (attached drawing) and the A5 flow adjusting
solenoid valve, and measure the resistance between ports J2-8 and J2-24 of connector and the
grounding . The resistance should be greater than 100kΩ.

Definition of
connector pin
serial number

Whether the harness of flow adjusting solenoid valve is shorted to ground or not?
YES NO
Connect the harness again and wrap the harness.
Go to Step 4 Go to Step 3
 6-145
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.43 DTC 151504 A5 Flow Adjusting Solenoid Shorted to Ground

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Notice: Shutdown operation is needed.
Inspection method
Connect the flow adjusting solenoid valve connector and disconnect the controller connector. Turn the
multimeter to its resistance function, and measure the resistance between the ports of J2-8 and J2-24
of controller (normally, 16~40Ω). When the resistance is abnormal, this indicates there is a fault in the
connector.
Whether the connector is faulty?
YES NO
Replace the connector.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-146
6.4 Fault Code December 30, 2017
6.4.44 DTC 151505 A5 Flow Adjusting Solenoid Valve Open-Circuited or Shorted to the Battery CLG930E/

6.4.44 DTC 151505 A5 Flow System description

Adjusting Solenoid Valve Open- The controller outputs a signal to the flow
Circuited or Shorted to the adjusting solenoid valve through the harness
(No. 908) which feeds back the valve port
Battery opening through the harness (No. 924). The
controller performs logical judgement and then
DTC Description Consequence adjusts the signal to control the valve port
opening through the harness (No. 908).
A5 flow adjusting
solenoid valve is open- There is no flow
151505
circuited or shorted to adjustment.
the battery.

Component location Attached drawing

Front
Controller
A5-marked solenoid
valve can be located.

Controller connector
Front
 6-147
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.44 DTC 151505 A5 Flow Adjusting Solenoid Valve Open-Circuited or Shorted to the

Fault diagnosis and troubleshooting steps

Step 1 Check the flow adjusting solenoid valve for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position, and disconnect the connector from the flow adjusting solenoid
valve.
1. Check the connector for looseness, rust, bending and damage.
2. Measure the resistance between both ends of the A5 flow adjusting solenoid valve (normally16-
40Ω).
Whether the flow adjusting valve fails?
YES NO
Repair or replace the flow adjusting solenoid valve.
Go to Step 5 Go to Step 2

Step 2 Check the harness for open-circuit

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
6-148
6.4 Fault Code December 30, 2017
6.4.44 DTC 151505 A5 Flow Adjusting Solenoid Valve Open-Circuited or Shorted to the Battery CLG930E/

Inspection method
1. Check the harness (# 908) and the feedback wire (# 924) between the controller (J2-9) (attached
drawing) and the flow adjusting solenoid valve for wear.
2. Disconnect the connectors from flow adjusting solenoid valve and the controller. Check the harness
for open-circuit:
(1) Turn the multimeter to its resistance function, and measure the resistance between the connector
terminals J2-8 and flow adjusting solenoid valve port A5-1 (normally, <10Ω).
(2) Turn the multimeter to its resistance function, and measure the resistance between the connector
terminals J2-24 and flow adjusting solenoid valve port A5-2 (normally, <10Ω).

Definition of
connector pin
serial number

Is the harness open-circuit?

YES NO
Connect the harness again and wrap the harness.
Go to Step 5 Go to Step 3
 6-149
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.44 DTC 151505 A5 Flow Adjusting Solenoid Valve Open-Circuited or Shorted to the

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Notice: Shutdown operation is needed.
Inspection method
Connect the flow adjusting solenoid valve connector and disconnect the controller connector. Turn the
multimeter to its resistance function, and measure the resistance between the harness at the controller
port J2-8 and the grounding (normally, 16~40Ω). When the resistance is abnormal, this indicates there
is a fault in the connector.
Whether the connector is faulty?
YES NO
Replace the connector.
Go to Step 5 Go to Step 4

Step 4 Check whether the flow adjusting solenoid valve is shorted to the battery

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the ON position for fault diagnosis.
Disconnect the connectors from the controller and flow adjusting solenoid valve to switch on the
switches of all electrical equipment, and then measure the voltage of the harness of flow adjusting
solenoid valve. The voltage should be 0V.
Whether the flow adjusting solenoid valve is shorted to the battery or not?
YES NO
Find out the short circuit position and re-connect
the harness and wrap it
Go to Step 5 Go to Step 5

Step 5 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-150
6.4 Fault Code December 30, 2017
6.4.45 DTC 151605 A6 Flow Adjusting Solenoid Open-circuited or Shorted to the Battery CLG930E/936E

6.4.45 DTC 151605 A6 Flow System description

Adjusting Solenoid Open- The controller outputs a signal to the flow
circuited or Shorted to the Battery adjusting solenoid valve through the harness
(No. 909) which feeds back the valve port
opening through the harness (No. 924). The
DTC Description Consequence controller performs logical judgement and then
A6 flow adjusting adjusts the signal to control the valve port
solenoid valve is open- There is no flow opening through the harness (No. 909).
151605
circuited or shorted to adjustment.
the battery.

Component location Attached drawing

Front
Controller
A6-marked solenoid
valve can be located.

Controller connector
Front
 6-151
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.45 DTC 151605 A6 Flow Adjusting Solenoid Open-circuited or Shorted to the Battery

Fault diagnosis and troubleshooting steps

Step 1 Check the flow adjusting solenoid valve for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position, and disconnect the connector from the flow adjusting solenoid
valve.
1. Check the connector for looseness, rust, bending and damage.
2. Measure the resistance between both ends of the A6 flow adjusting solenoid valve (normally16-
40Ω).
Whether the flow adjusting valve fails?
YES NO
Repair or replace the flow adjusting solenoid valve.
Go to Step 5 Go to Step 2

Step 2 Check the harness for open-circuit

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
6-152
6.4 Fault Code December 30, 2017
6.4.45 DTC 151605 A6 Flow Adjusting Solenoid Open-circuited or Shorted to the Battery CLG930E/936E

Inspection method
1. Check the harness (# 909) and the feedback wire (# 924) between the controller (J2-9) (attached
drawing) and the flow adjusting solenoid valve for wear.
2. Disconnect the connectors from flow adjusting solenoid valve and the controller. Check the harness
for open-circuit:
(1) Turn the multimeter to its resistance function, and measure the resistance between the control
connector terminal J2-9 and flow adjusting solenoid valve port A6-1 (normally, <10Ω).
(2) Turn the multimeter to its resistance function, and measure the resistance between the controller
connector terminal J2-24 and flow adjusting solenoid valve connector port A6-2 (normally, <10Ω).

Definition of
connector pin
serial number

Is the harness open-circuit?

YES NO
Connect the harness again and wrap the harness.
Go to Step 5 Go to Step 3
 6-153
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.45 DTC 151605 A6 Flow Adjusting Solenoid Open-circuited or Shorted to the Battery

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Notice: Shutdown operation is needed.
Inspection method
Connect the flow adjusting solenoid valve connector and disconnect the controller connector. Turn the
multimeter to its resistance function, and measure the resistance between the ports of J2-9 and J2-24
of controller connector in the harness (normally, 16~40Ω). When the resistance is abnormal, this
indicates there is a fault in the connector.
Whether the connector is faulty?
YES NO
Replace the connector.
Go to Step 5 Go to Step 4

Step 4 Check whether the flow adjusting solenoid valve is shorted to the battery

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the ON position for fault diagnosis.
Disconnect the connectors from the controller and flow adjusting solenoid valve to switch on the
switches of all electrical equipment, and then measure the voltage of the harness of flow adjusting
solenoid valve. The voltage should be 0V.
Whether the flow adjusting solenoid valve is shorted to the battery or not?
YES NO
Find out the short circuit position and re-connect
the harness and wrap it
Go to Step 5 Go to Step 5

Step 5 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-154
6.4 Fault Code December 30, 2017
6.4.46 DTC 151704 A7 Power Boosting Solenoid Valve Shorted to the Ground CLG930E/936E

6.4.46 DTC 151704 A7 Power System description

Boosting Solenoid Valve Shorted Sends a power boosting signal automatically or
to the Ground manually to control on-off of the solenoid valve
port to achieve the power boosting

DTC Description Consequence

The transient power No transient
151704 boosting solenoid valve power boosting
is shorted to ground function.

Component location Attached drawing

Front Controller
A7-marked solenoid
valve can be located.

Controller connector
Front
 6-155
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.46 DTC 151704 A7 Power Boosting Solenoid Valve Shorted to the Ground

Fault diagnosis and troubleshooting steps

Step 1 Check the transient power boosting solenoid valve for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position and disconnect the connector from the connector of the
transient power boosting solenoid valve.
1. Check the pins for moisture, oil dirt and other.
2. Measure the resistance between both ends of the transient power boosting solenoid valve. The
resistance should be 16-40Ω
Whether the transient power boosting solenoid valve fails?
YES NO
Repair or replace the transient power boosting
solenoid valve.
Go to Step 4 Go to Step 2

Step 2 Check whether the power line of the power boosting solenoid valve is shorted to ground.

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Turn the start switch to the OFF position for fault diagnosis.
2. Disconnect the connectors from the controller (Attached drawing) and power boosting solenoid
valve, and measure the resistance between the power line (No. 813) of the power boosting solenoid
valve and the grounding. The resistance should be more than 100kΩ.
Whether the harness is shorted to ground or not?
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
6-156
6.4 Fault Code December 30, 2017
6.4.46 DTC 151704 A7 Power Boosting Solenoid Valve Shorted to the Ground CLG930E/936E

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the transient power boosting solenoid valve connector and disconnect the controller
connector. Turn the multimeter to its resistance function, and measure the resistance between the
harness at the controller port J1-13 and the grounding (normally, 16~40Ω). When the resistance is
abnormal, this indicates there is a fault in the connector.

Definition of
connector pin
serial number

Whether the connector is faulty?

YES NO
Replace the connector.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-157
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.48 DTC 151705 A7 Power Boosting Solenoid Valve Open-Circuited or Shorted to the

6.4.48 DTC 151705 A7 Power System description

Boosting Solenoid Valve Open- Sends a power boosting signal automatically or
Circuited or Shorted to the manually to control on-off of the solenoid valve
port to achieve the power boosting
Battery

DTC Description Consequence

There is no
The power boosting
transient power
solenoid valve is open-
151705 boosting or the
circuited or shorted to
power boosting
the battery
is kept.

Component location Attached drawing

Front Controller
A7-marked solenoid
valve can be located.

Controller connector
Front
6-158
6.4 Fault Code December 30, 2017
6.4.48 DTC 151705 A7 Power Boosting Solenoid Valve Open-Circuited or Shorted to the Battery CLG930E/

Fault diagnosis and troubleshooting steps

Step 1 Check the transient power boosting solenoid valve for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position and disconnect the connector from the connector of the
transient power boosting solenoid valve.
1. Check the pins for moisture, oil dirt and other.
2. Measure the resistance between both ends of the transient power boosting solenoid valve. The
resistance should be 16-40Ω
Whether the transient power boosting solenoid valve fails?
YES NO
Repair or replace the transient power boosting
solenoid valve.
Go to Step 5 Go to Step 2

Step 2 Check the harness for open-circuit

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
 6-159
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.48 DTC 151705 A7 Power Boosting Solenoid Valve Open-Circuited or Shorted to the

Inspection method
1. Check the harness (No.813) and the grounding wire (No.224) between the controller (J1-13) (in the
figure) and the power boosting solenoid valve for wear.
2. Disconnect the connectors from the power boosting solenoid valve and the controller, and check
the harness for open-circuit:
(1) Turn the multimeter to its resistance function, and measure the resistance between the controller
port J1-13 and power boosting solenoid valve harness (normally, <10Ω).
(2) Turn the multimeter to its resistance function, and measure the resistance between the grounding
wire (#224) power boosting solenoid valve terminal and the grounding (normally, <10Ω).

Definition of
connector pin
serial number

Is the harness open-circuit?

YES NO
Connect the harness again and wrap the harness
Go to Step 5 Go to Step 3
6-160
6.4 Fault Code December 30, 2017
6.4.48 DTC 151705 A7 Power Boosting Solenoid Valve Open-Circuited or Shorted to the Battery CLG930E/

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the transient power boosting solenoid valve connector and disconnect the controller
connector. Turn the multimeter to its resistance function, and measure the resistance between the
harness at the controller port J1-13 and the grounding (normally, 16~40Ω). When the resistance is
abnormal, this indicates there is a fault in the connector.
Whether the connector is faulty?
YES NO
Replace the connector.
Go to Step 5 Go to Step 4

Step 4 Check whether the power boosting solenoid valve is shorted to the battery

Inspection method
Turn the start switch to the ON position for fault diagnosis.
Disconnect the connectors from the controller and A7 transient power boosting solenoid valve to switch
on the switches of all electrical equipment, and then measure the voltage of the harness of A7 transient
power boosting solenoid valve. The voltage should be 0V.
Whether the power boosting solenoid valve is shorted to the battery?
YES NO
Find out the short circuit position and re-connect
the harness and wrap it.
Go to Step 5 Go to Step 5

Step 5 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-161
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.49 DTC 151804 A4 Travel Lifting Solenoid Valve Shorted to the Ground

6.4.49 DTC 151804 A4 Travel System description

Lifting Solenoid Valve Shorted to The controller outputs an electric signal to the
the Ground travel lifting solenoid valve A4 through the
harness (# 826) to open the valve port.

DTC Description Consequence

The travel lifting solenoid There is no
151804 valve is shorted to travel lifting
ground. function.

J2

Component location Attached drawing

Front
Controller
A4-marked solenoid
valve can be located.

Controller connector
Front
6-162
6.4 Fault Code December 30, 2017
6.4.49 DTC 151804 A4 Travel Lifting Solenoid Valve Shorted to the Ground CLG930E/936E

Fault diagnosis and troubleshooting steps

Step 1 Check the travel lifting solenoid valve for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position and disconnect the connector from the travel lifting solenoid
valve.
1. Check the pins for moisture, oil dirt and other.
2. Measure the resistance between both ends of the travel lifting solenoid valve. The resistance
should be 16~40Ω.
Whether the travel lifting solenoid valve fails?
YES NO
Repair or replace the travel lifting solenoid valve.
Go to Step 4 Go to Step 2

Step 2 Check whether the power line of the travel lifting solenoid valve is shorted to ground.

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Turn the start switch to the OFF position for fault diagnosis.
2. Disconnect the connectors from the controller (attached drawing) and the travel lifting solenoid
valve, and measure the resistance between the power line (No. 826) of the travel lifting solenoid
valve and the grounding. The resistance should be greater than 100kΩ.
Whether the harness is shorted to ground or not?
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
 6-163
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.49 DTC 151804 A4 Travel Lifting Solenoid Valve Shorted to the Ground

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the travel lifting solenoid valve connector and disconnect the controller connector. Turn the
multimeter to its resistance function, and measure the resistance between the harness at the controller
port J2-26 and the grounding (normally, 16~40Ω). When the resistance is abnormal, this indicates there
is a fault in the connector.

Definition of
connector pin
serial number

Whether the connector is faulty?

YES NO
Replace the connector.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-164
6.4 Fault Code December 30, 2017
6.4.50 DTC 151805 A4 Travel Lifting Solenoid Valve Open-Circuited or Shorted to the Battery CLG930E/

6.4.50 DTC 151805 A4 Travel System description

Lifting Solenoid Valve Open- The controller outputs a signal to the travel lifting
Circuited or Shorted to the solenoid valve A4 through the harness (# 825) to
open the valve port.
Battery

DTC Description Consequence

There is no
travel lifting
Travel lifting solenoid function or the
151805 valve is open-circuited or travel lifting
shorted to the battery. solenoid valve is
uncontrolled by
the controller.

J2

Component location Attached drawing

Front
Controller
A4-marked solenoid
valve can be located.

Controller connector
Front
 6-165
December 30, 2017 6.4 Fault Code
CLG930E/936E6.4.50 DTC 151805 A4 Travel Lifting Solenoid Valve Open-Circuited or Shorted to the Battery

Fault diagnosis and troubleshooting steps

Step 1 Check the travel lifting solenoid valve for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position and disconnect the connector from the travel lifting solenoid
valve:
1. Check the connector for looseness, rust, bending and damage.
2. Measure the resistance between both ends of the travel lifting solenoid valve (normally,16~40Ω )
Whether the travel lifting solenoid valve fails?
YES NO
Repair or replace the travel lifting solenoid valve.
Go to Step 5 Go to Step 2

Step 2 Check whether the power harness of the travel lifting solenoid valve is shorted to ground

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
6-166
6.4 Fault Code December 30, 2017
6.4.50 DTC 151805 A4 Travel Lifting Solenoid Valve Open-Circuited or Shorted to the Battery CLG930E/

Inspection method
1. Check the harness (No. 826) and the grounding wire (No. 223) between the controller J2-26
(attached drawing) and the travel lifting solenoid valve for wear.
2. Disconnect the connectors from the travel lifting solenoid valve and the controller, and check the
harness for open-circuit:
(1) Turn the multimeter to its resistance function, and measure the resistance between the controller
port J2-26 and travel speed solenoid valve harness (normally, <10Ω).
(2) Turn the multimeter to its resistance function, and measure the resistance between the grounding
wire (# 223) travel lifting solenoid valve terminal and the grounding (normally, <10Ω).

Definition of
connector pin
serial number

Whether the power harness of the travel lifting solenoid valve is shorted to ground?
YES NO
Connect the harness again and wrap the harness.
Go to Step 5 Go to Step 3
 6-167
December 30, 2017 6.4 Fault Code
CLG930E/936E6.4.50 DTC 151805 A4 Travel Lifting Solenoid Valve Open-Circuited or Shorted to the Battery

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the travel lifting solenoid valve connector and disconnect the controller connector. Turn the
multimeter to its resistance function, and measure the resistance between the harness (#826) at the
controller port J2-26 and the grounding (normally, 16~40Ω). When the resistance is abnormal, this
indicates there is a fault in the connector.
Whether the connector is faulty?
YES NO
Replace the connector.
Go to Step 5 Go to Step 4

Step 4 Check whether the travel lifting solenoid valve is shorted to the battery

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the ON position for fault diagnosis.
Disconnect the connectors from the controller and A4 travel lifting solenoid valve to switch on the
switches of all electrical equipment, and then measure the voltage of the harness of A4 travel lifting
solenoid valve. The voltage should be 0 V.
Whether the travel lifting solenoid valve is shorted to the battery or not?
YES NO
Find out the short circuit position and re-connect
the harness and wrap it
Go to Step 5 Go to Step 5

Step 5 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-168
6.4 Fault Code December 30, 2017
6.4.50 DTC 151905 A5 or A6 Solenoid Valve Feedback Open-Circuited CLG930E/936E

6.4.50 DTC 151905 A5 or A6 System description

Solenoid Valve Feedback Open- The controller sends a signal through which A5
Circuited or A6 adjusts the hydraulic flow.

DTC Description Consequence

A5 or A6 flow adjusting
The flow cannot
151905 solenoid valve is open
be adjusted.
circuit.

Component location Attached drawing

Solenoid valve
assembly. Both
A5-marked solenoid
and A6-marked Controller
solenoid can be
located

Front

Controller connector
Front
 6-169
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.50 DTC 151905 A5 or A6 Solenoid Valve Feedback Open-Circuited

Fault diagnosis and troubleshooting steps

Step 1 Check the flow adjusting solenoid valve for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Notice: Shutdown operation is needed.
Inspection method
3. Turn the start switch to the OFF position, and check the pins for moisture, oil dirt and other.
4. Measure the resistance of A5 or A6 flow adjusting solenoid valve. The resistance should be
16~40Ω.
Whether the flow adjusting valve fails?
YES NO
Repair or replace the flow adjusting solenoid valve.
Go to Step 4 Go to Step 2

Step 2 Check the harness for open-circuit

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Turn the start switch to the OFF position,
2. Disconnect the connectors from the controller (attached drawing), A5 and A6 flow adjusting
solenoid valves, and measure the resistance between the J2-24 wire and the A5, A6 flow adjusting
solenoid valve, normally the resistance should be less than 10Ω.
Is the harness open-circuit?
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
6-170
6.4 Fault Code December 30, 2017
6.4.50 DTC 151905 A5 or A6 Solenoid Valve Feedback Open-Circuited CLG930E/936E

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Check the connectors between the A5/A6 flow adjusting solenoid valve and the controller for
looseness and their pins for rust, bending and damage one by one manually.
Disconnect the controller connector and connect the connector of the A5, A6 flow adjusting solenoid
valve, and then measure the resistance between the controller connector terminals J2-8, J2-9 and J2-
24 respectively. The resistance should be 16-40Ω. Otherwise, there is a fault in the connector.
Whether the connector is faulty?
YES NO
Replace the connector.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-171
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.51 DTC 151906 A5 or A6 Solenoid Valve Feedback Overcurrent

6.4.51 DTC 151906 A5 or A6 System description

Solenoid Valve Feedback The controller sends a signal through which A5
Overcurrent or A6 adjusts the hydraulic flow.

DTC Description Consequence

A5 or A6 flow adjusting
The flow cannot
151906 solenoid valve is open
be adjusted.
circuit.

Component location Attached drawing

Solenoid valve
assembly. Both
A5-marked solenoid
and A6-marked Controller
solenoid can be
located

Front

Controller connector
Front
6-172
6.4 Fault Code December 30, 2017
6.4.51 DTC 151906 A5 or A6 Solenoid Valve Feedback Overcurrent CLG930E/936E

Fault diagnosis and troubleshooting steps

Step 1 Check the flow adjusting solenoid valve for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Notice: Shutdown operation is needed.
Inspection method
3. Turn the start switch to the OFF position, and check the pins for moisture, oil dirt and other.
4. Measure the resistance of A5 or A6 flow adjusting solenoid valve. The resistance should be
16~40Ω.
Whether the flow adjusting valve fails?
YES NO
Repair or replace the flow adjusting solenoid valve.
Go to Step 4 Go to Step 2

Step 2 Check whether the harness is shorted to the battery.

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
Disconnect the connectors from the controller, A5 and A6 solenoid valves, respectively
Measure the voltage between the controller (attached drawing) connector terminal J2-24 and the
ground with the voltmeter (200V). The voltage should be 0V.
Whether the harness is shorted to the battery or not?
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
 6-173
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.51 DTC 151906 A5 or A6 Solenoid Valve Feedback Overcurrent

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Check the connectors between the A5/A6 flow adjusting solenoid valve and the controller for
looseness and their pins for rust, bending and damage one by one manually.
Whether the connector is faulty?
YES NO
Replace the connector.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-174
6.4 Fault Code December 30, 2017
6.4.52 DTC 171004 SHORT CIRCUIT TO GROUND OF BATTERY RELAY CLG930E/936E

6.4.52 DTC 171004 SHORT The alternator’s

load dump may
CIRCUIT TO GROUND OF Battery relay is shorted burn electronic
171004
BATTERY RELAY to ground components and
electrical
equipment.
DTC Description Consequence
System description

When the B or L terminal is connected to the

positive pole of the power (24V) and the E
terminal to the negative pole, the energized coil
generates a magnetic field suction to move the
 6-175
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.52 DTC 171004 SHORT CIRCUIT TO GROUND OF BATTERY RELAY

Component location

Front

Battery relay
6-176
6.4 Fault Code December 30, 2017
6.4.52 DTC 171004 SHORT CIRCUIT TO GROUND OF BATTERY RELAY CLG930E/936E

Fault diagnosis and troubleshooting steps

Step 1 Check the battery relay for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position and turn the multimeter to its resistance function (200Ω), and
then measure the resistance between the relay terminals B and E (normally, >10Ω, about 142Ω).
Is battery relay malfunctioning?
YES NO
Replace the battery relay
Go to Step 3 Go to Step 2

Step 2 Check whether the harness is shorted to ground

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Check the harness (No. 824) between the controller (J1-24) and the battery relay for wear.
2. Disconnect the relay connector and the controller connector. Turn the multimeter to its resistance
function, and measure the resistance between the harness (No. 824) relay terminal and the ground
(normally, >100kΩ).
Whether the harness is shorted to ground or not?
YES NO
Connect the harness again and wrap the harness
Go to Step 3 Go to Step 3

Step 3 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-177
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.53 DTC 171104 Auto Preheating Relay Shorted to the Ground

6.4.53 DTC 171104 Auto System description

Preheating Relay Shorted to the The controller needs to be preheated before
Ground logical judgment. If the harness (No. 911) outputs
24V, the auto preheater K9 is energized and the
harness (No. 123) is connected to the harness
DTC Description Consequence (No. 190), then the harness (No. 190) is
The auto preheating The auto energized. As a result, the preheating relay K3 is
171104 relay is shorted to preheating energized, so that the harness (No. 104) is
ground function fails. connected to the harness (No. 185) which
connects the heater for heating.
6-178
6.4 Fault Code December 30, 2017
6.4.53 DTC 171104 Auto Preheating Relay Shorted to the Ground CLG930E/936E

Component location

Open the fuse box.

K9 auto preheating
relay. It can be pulled
out during detection`

Fault diagnosis and troubleshooting steps

Step 1 Check whether the harness connecting the controller is shorted to ground

Notice: Shutdown operation is needed

Inspection method
Turn the start switch to the OFF position for fault diagnosis.
Disconnect the connector J2 from the controller and pull out the auto preheating relay, and then
measure the resistance between the harness (# 911) at the J2-11 port and the grounding. The
resistance should be infinite
Check whether the harness connecting the controller is shorted to ground.
YES NO
Re-connect the harness, and wrap it.
Go to Step 3 Go to Step 2
 6-179
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.53 DTC 171104 Auto Preheating Relay Shorted to the Ground

Step 2 Check the connectors for fault

Notice: Shutdown operation is needed

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Check manually the connectors between the automatic preheating relay and the controller one by one
for moisture, oil dirt and other which may cause electric leakage.
Whether the connector fails?
YES NO
Adjust or replace the connector.
Go to Step 3 Go to Step 3

Step 3 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-180
6.4 Fault Code December 30, 2017
6.4.54 DTC 171105 Auto Preheating Relay Open-Circuited or Shorted to the Battery CLG930E/936E

6.4.54 DTC 171105 Auto System description

Preheating Relay Open-Circuited The controller needs to be preheated before
or Shorted to the Battery logical judgment. If the harness (No. 911) outputs
24V, the auto preheater K9 is energized and the
harness (No. 123) is connected to the harness
DTC Description Consequence (No. 190), then the harness (No. 190) is
Auto preheating relay is The auto energized. As a result, the preheating relay K3 is
171105 open-circuited or shorted preheating energized, so that the harness (No. 104) is
to the battery. function fails. connected to the harness (No. 185) which
connects the heater for heating.
 6-181
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.54 DTC 171105 Auto Preheating Relay Open-Circuited or Shorted to the Battery

Component location

Open the fuse box.

K9 auto preheating
relay. It can be pulled
out during detection`

Fault diagnosis and troubleshooting steps

Step 1 Check the auto preheating relay for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position for fault diagnosis
Open the fuse box, and pull out the auto preheating relay.
Measure the resistance between the ports 85 and 86 of the auto preheating relay coil. The resistance
should be 320-360Ω.
Connect the ports 85 and 86 to the power supply (24V), and measure the ports 30 and 87 by turning the
multimeter to its on-off function. The relay should switch on.
Whether the auto preheating relay fails?
YES NO
Replace the auto preheating relay.
Go to Step 4 Go to Step 2
6-182
6.4 Fault Code December 30, 2017
6.4.54 DTC 171105 Auto Preheating Relay Open-Circuited or Shorted to the Battery CLG930E/936E

Step 2 Check the harness for open-circuit

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
Turn the start switch to the OFF position for fault diagnosis
Disconnect the connector J2 from the controller and pull out the auto preheating relay, and then
measure the resistance between the harness (# 911) at the J2-11 port and the auto preheating relay
socket. The maximum resistance should be less than10Ω.
Measure the resistance between the 85 port in the fuse box and the ground. Normally, the resistance
should be less than 10Ω.
Is the harness open-circuit?
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3

Step 3 Check the connectors for fault

Notice: Shutdown operation is needed

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Insert the automatic preheating relay properly into the fuse box, disconnect the controller connector,
and measure the resistance between J2-11 and 230 of controller using the omh band of the multimeter,
and the resistance should be between 320-360Ω, and in case of abnormal, please check the automatic
preheating relay for proper contact, and the connector for looseness or damage.
Whether the connector fails?
YES NO
Adjust or replace the connector.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-183
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.55 DTC 171204 Start Cut-off Relay Shorted to Ground

6.4.55 DTC 171204 Start Cut-off System description

Relay Shorted to Ground After the controller port 23 is energized, the
harness (# 923) is energized, so that the ports 30
and 87A of the start cut-off relay K8 are switched
DTC Description Consequence
off.
The start cut-off
Start cut-off valve relay is relay is not
171204
shorted to ground controlled by the
controller.

Component location Attached drawing

Controller

Open the fuse box.

Start cut-off relay K8

Controller connector
Front
6-184
6.4 Fault Code December 30, 2017
6.4.55 DTC 171204 Start Cut-off Relay Shorted to Ground CLG930E/936E

Fault diagnosis and troubleshooting steps

Step 1 Check whether there is a fault in the start cut-off relay

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position for fault diagnosis
Open the fuse box, and pull out the auto preheating relay.
Measure the resistance between the ports 85 and 86 of the start cut-off relay coil. The resistance
should be 320-360Ω.
Connect the ports 85 and 86 to the power supply (24V), and measure the ports 30 and 87 by turning the
multimeter to its on-off function. The relay should switch on.
Whether the start cut-off relay fails?
YES NO
Replace the relay.
Go to Step 4 Go to Step 2

Step 2 Check whether the power harness of the start cut-off relay is shorted to ground

Notice: Shutdown operation is needed

Notice: Correctly tie up harness and wire:
Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Turn the start switch to the OFF position for fault diagnosis.
2. Disconnect the connectors from the controller (Attached drawing) and the start cut-off relay, and
measure the resistance between the power line (No. 923) of the start cut-off relay and the
grounding, the resistance should be infinite
Whether the harness is shorted to ground or not?
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
 6-185
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.55 DTC 171204 Start Cut-off Relay Shorted to Ground

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the connector of the start cut-off relay and disconnect the controller connector, and then turn
the multimeter to its resistance function and measure the resistance between the harness at the
controller port J2-23 and the grounding (normally, 320-360Ω). If the resistance is abnormal, this
indicates that there is a fault in the connector.

Definition of
connector pin
serial number

Whether the connector is faulty?

YES NO
Replace the connector.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-186
6.4 Fault Code December 30, 2017
6.4.56 DTC 171205 Start cut-off Output Open-circuited or Shorted to the Battery CLG930E/936E

6.4.56 DTC 171205 Start cut-off System description

Output Open-circuited or Shorted After the controller port 23 is energized, the
to the Battery harness (# 923) is energized, so that the ports 30
and 87A of the start cut-off relay K8 are switched
off.
DTC Description Consequence
The start cut-off
The start cut-off output is
relay is not
171205 open-circuited or shorted
controlled by the
to the battery.
controller.

Component location Attached drawing

Controller

Open the fuse box.

Start cut-off relay K8

Controller connector
Front
 6-187
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.56 DTC 171205 Start cut-off Output Open-circuited or Shorted to the Battery

Fault diagnosis and troubleshooting steps

Step 1 Check whether there is a fault in the start cut-off relay

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position for fault diagnosis
Open the fuse box, and pull out the auto preheating relay.
Measure the resistance between the ports 85 and 86 of the start cut-off relay coil. The resistance
should be 320-360Ω.
Connect the ports 85 and 86 to the power supply (24V), and measure the ports 30 and 87 by turning the
multimeter to its on-off function. The relay should switch on.
Whether the start cut-off relay fails?
YES NO
Replace the relay.
Go to Step 5 Go to Step 2

Step 2 Check the harness for open-circuit

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
Turn the start switch to the OFF position for fault diagnosis
Disconnect the connector from the controller (Attached drawing ) and pull out the start cut-off relay, and
then measure the resistance between the harness (No. 923) at the J2-23 port and the start cut-off relay.
The maximum resistance should be less than 10Ω.
Measure the resistance between the 85 port in the fuse box and the ground. Normally, the resistance
should be less than 10Ω.
Is the harness open-circuit?
YES NO
Connect the harness again and wrap the harness
Go to Step 5 Go to Step 3
6-188
6.4 Fault Code December 30, 2017
6.4.56 DTC 171205 Start cut-off Output Open-circuited or Shorted to the Battery CLG930E/936E

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Insert the start cut-off relay into the fuse box properly and disconnect the controller connector, and then
turn the multimeter to its resistance function and measure the resistance between the harness (# 923)
at the controller port J2-23 and the grounding. The resistance should be between 320-360Ω.
Otherwise, check the connector:
1. Check the connector at the grounding of the start cut-off relay for poor contact
2. Check the connector of the start cut-off relay for looseness or damage.
Whether the connector is faulty?
YES NO
Adjust or replace the connector.
Go to Step 5 Go to Step 4

Step 4 Check whether the start cut-off relay is shorted to the battery

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the ON position for fault diagnosis.
Disconnect the connectors from the controller and the start cut-off relay and turn on the switches of all
electrical equipment, and then measure the voltage of the harness connecting the start cut-off relay.
The voltage should be 0V.
Whether the start cut-off relay is shorted to the battery or not?
YES NO
Find out the short circuit position and re-connect
the harness and wrap it
Go to Step 5 Go to Step 5

Step 5 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-189
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.57 DTC 201004 Travel Alarm Shorted to Ground

6.4.57 DTC 201004 Travel Alarm System description

Shorted to Ground The travel alarm is used to beep for warning
when the machine is moving, as shown in the
figure. One pin of the travel alarm is connected to
DTC Description Consequence
the controller directly and the other pin is
Travel alarm is shorted Travel alarm fails grounded. When the machine is moving, the
201004
to ground to work controller receives the traveling signal and allows
the travel alarm to be energized through its
internal logic program.

Component location

Front

Travel alarm
6-190
6.4 Fault Code December 30, 2017
6.4.57 DTC 201004 Travel Alarm Shorted to Ground CLG930E/936E

Fault diagnosis and troubleshooting steps

Step 1 Check the travel alarm for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position, and disconnect the travel alarm connector:
1. Check the connector for moisture, oil dirt and other
2. Turn the multimeter to its resistance function, and measure the resistance between the alarm
connector terminals 1 and 2 (normally, >10Ω).
Check the backup alarm for fault
YES NO
Replace the alarm.
Go to Step 4 Go to Step 2

Step 2 Check whether the harness is shorted to ground

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Check the harness (# 801) between the controller (J1-01) and the travel alarm for wear.
2. Disconnect the travel alarm connector and the controller connector. Turn the multimeter to its
resistance function, and measure the resistance between the harness (# 801) sensor terminal and
grounding (normally, >100kΩ).
Whether the harness is shorted to ground or not?
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
 6-191
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.57 DTC 201004 Travel Alarm Shorted to Ground

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the travel alarm connector and disconnect the controller connector. Turn the multimeter to its
resistance function, and measure the resistance between the controller port J1-01 and the grounding
(normally, >10Ω)
When the resistance is abnormal, this indicates there is an insulation fault in the connector
Whether the connector is faulty?
YES NO
Replace the connector.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-192
6.4 Fault Code December 30, 2017
6.4.58 DTC 211003 P1 Pump Pressure Sensor Voltage Above the Range Value CLG930E/936E

6.4.58 DTC 211003 P1 Pump Pressure Sensor Voltage Above the Range
Value

DTC Description Consequence

The P1 pump pressure sensor voltage is out of the
range value. (When the left/right control level is
If the machine is operated as usual, the engine
211003 operated, the voltage detected in the signal circuit of
will get stuck or even shut down
the P1 pump pressure sensor is higher than the normal
value.)

System description

The pressure sensor (pressure transmitter) converts the detected hydraulic oil pressure parameter into
the electric signal, which is input to the controller, then the controller detects electric signal and
calculates the hydraulic oil pressure value which is displayed on the display instrument.

Pressure sensor parameters:

Output voltage: 0-4.5V
Working voltage: 5Vdc
Pressure range: 0-500bar

Component location

P1 pump
pressure sensor

P2 pump
pressure sensor

Front
 6-193
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.58 DTC 211003 P1 Pump Pressure Sensor Voltage Above the Range Value

Fault diagnosis and troubleshooting steps

Step 1 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Check the connector for moisture, oil dirt or insulation fault.
Whether the connector is faulty?
YES NO
Replace the connector.
Go to Step 4 Go to Step 2

Step 2 Check the harness for short-circuit to battery

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Check the harness (# 931) between the controller (J2-31) and the pump pressure sensor for wear.
2. Turn the start switch to ON position, and measure the voltage (0.5V normal) between
harness(No.931) sensor end and ground using voltage band of the multimeter.
Whether the harness is shorted to the battery.
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
6-194
6.4 Fault Code December 30, 2017
6.4.58 DTC 211003 P1 Pump Pressure Sensor Voltage Above the Range Value CLG930E/936E

Step 3 Check the pump pressure sensor for fault.

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Start the engine, and measure the voltage of No. 931 harness using voltage band of the multimeter with
the boom lifted (normal range 0.5-4.5V) .
Whether the pump pressure sensor fails?
YES NO
Replace the pump pressure sensor
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-195
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.59 DTC 211004 P1 Pump Pressure Sensor Voltage Below the Range Value

6.4.59 DTC 211004 P1 Pump Pressure Sensor Voltage Below the Range
Value

DTC Description Consequence

The P1 pump pressure sensor voltage is lower than the
range value. When the left/right control level is
211004 Some hydraulic actions cannot be achieved.
operated, the voltage detected in the signal circuit of
the P1 pump pressure sensor is extremely low (<0.5V).

System description

The pressure sensor (pressure transmitter) converts the detected hydraulic oil pressure parameter into
the electric signal, which is input to the controller, then the controller detects electric signal and
calculates the hydraulic oil pressure value which is displayed on the display instrument.

Pressure sensor parameters:

Output voltage: 0.5-4.5V
Working voltage: 5Vdc
Pressure range: 0-500bar

Component location

P1 pump
pressure sensor

P2 pump
pressure sensor

Front
6-196
6.4 Fault Code December 30, 2017
6.4.59 DTC 211004 P1 Pump Pressure Sensor Voltage Below the Range Value CLG930E/936E

Fault diagnosis and troubleshooting steps

Step 1 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
1. Check the connector at the sensor grounding for poor contact
2. Check whether the connector becomes loose.
3. Check the connector pins for rust, bending or damage.
Whether the connector is faulty?
YES NO
Repair or replace the connector.
Go to Step 4 Go to Step 2

Step 2 Check the harness for open-circuit or short-circuit to ground.

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Check the harness (# 931) between the controller (J2-31) and the pump pressure sensor, the power
line (# 828) for wear.
Turn the start switch to ON position and disconnect the P1 connector.
2. Check the harness for open-circuit:
(1) Turn the multimeter to its voltage function, and measure the voltage between the power line (No.
828) sensor connecting terminal and the grounding (normally, 5V).
(2) Turn the multimeter to its resistance function, and measure the resistance of the harness (# 931)
between the controller and the sensor (normally, <10Ω)
3. Check whether the harness is shorted to ground:
Measure the resistance between the harness (# 931) sensor connecting terminal and the grounding
(normally, >100kΩ).
Whether the harness open-circuit or shorted to ground?
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
 6-197
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.59 DTC 211004 P1 Pump Pressure Sensor Voltage Below the Range Value

Step 3 Check the pump pressure sensor for fault.

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Start the engine, and measure the voltage of No. 931 harness using voltage band of the multimeter with
the boom lifted (normal range 0.5-4.5V) .
Whether the pump pressure sensor fails?
YES NO
Replace the pump pressure sensor
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-198
6.4 Fault Code December 30, 2017
6.4.60 DTC 211003 P2 Pump Pressure Sensor Voltage above the Range Value CLG930E/936E

6.4.60 DTC 211003 P2 Pump Pressure Sensor Voltage above the Range
Value

DTC Description Consequence

The P2 pump pressure sensor voltage is higher than
the range value. When the left/right control level is If the machine is operated as usual, the engine
211103
operated, the voltage detected in the signal circuit of will get stuck or even shut down.
the P2 pump pressure sensor is excessive (>4.5V).

System description

The pressure sensor (pressure transmitter) converts the detected hydraulic oil pressure parameter into
the electric signal, which is input to the controller, then the controller detects electric signal and
calculates the hydraulic oil pressure value which is displayed on the display instrument.

Pressure sensor parameters:

Output voltage: 0.5-4.5V
Working voltage: 5Vdc
Pressure range: 0-500bar

Component location

P1 pump
pressure sensor

P2 pump
pressure sensor

Front
 6-199
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.60 DTC 211003 P2 Pump Pressure Sensor Voltage above the Range Value

Fault diagnosis and troubleshooting steps

Step 1 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Check the connector for moisture, oil dirt or insulation fault.
Whether the connector is faulty?
YES NO
Repair or replace the connector.
Go to Step 4 Go to Step 2

Step 2 Check the harness for short-circuit to battery

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Check the harness (wire No. 932) between the controller (J2-32) and the pump pressure sensor for
wear.
2. Turn the start switch to ON position, and measure the voltage (0.5V normal) between
harness(No.932) sensor end and ground using voltage band of the multimeter.
Whether the harness is shorted to the battery.
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
6-200
6.4 Fault Code December 30, 2017
6.4.60 DTC 211003 P2 Pump Pressure Sensor Voltage above the Range Value CLG930E/936E

Step 3 Check the pump pressure sensor for fault.

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Start the engine, and measure the voltage of No. 932 harness using voltage band of the multimeter with
the boom lifted (normal range 0.5-4.5V) .
Whether the pump pressure sensor fails?
YES NO
Replace the pump pressure sensor
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-201
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.61 DTC 211104 P2 Pump Pressure Sensor Voltage below the Range Value

6.4.61 DTC 211104 P2 Pump Pressure Sensor Voltage below the Range
Value

DTC Description Consequence

The P2 pump pressure sensor voltage is lower than the
range value. (When the left/right control level is
211104 operated, the voltage detected in the signal circuit of Some hydraulic actions cannot be achieved
the P2 pump pressure sensor is extremely low
(<0.5V)).

System description

The pressure sensor (pressure transmitter) converts the detected hydraulic oil pressure parameter into
the electric signal, which is input to the controller, then the controller detects electric signal and
calculates the hydraulic oil pressure value which is displayed on the display instrument.

Pressure sensor parameters:

Output voltage: 0.5-4.5V
Working voltage: 5Vdc
Pressure range: 0-500bar

Component location

P1 pump
pressure sensor

P2 pump
pressure sensor

Front
6-202
6.4 Fault Code December 30, 2017
6.4.61 DTC 211104 P2 Pump Pressure Sensor Voltage below the Range Value CLG930E/936E

Fault diagnosis and troubleshooting steps

Step 1 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
1. Check the connector at the sensor grounding for poor contact
2. Check whether the connector becomes loose.
3. Check the connector pins for rust, bending or damage.
Whether the connector is faulty?
YES NO
Repair or replace the connector.
Go to Step 4 Go to Step 2

Step 2 Check the harness for open-circuit or short-circuit to ground.

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Check the harness (wire No. 932) between the controller (J2-32) and the pump pressure sensor,
the power line (wire No. 828) for wear.
Turn the start switch to ON position and disconnect the P2 connector.
2. Check the harness for open-circuit:
(1) Turn the multimeter to its voltage function, and measure the voltage between the power line (No.
828) sensor connecting terminal and the grounding (normally, 5V).
(2) Turn the multimeter to its resistance function, and measure the resistance of the harness (# 932)
between the controller and the sensor (normally, <10Ω)
3. Check whether the harness is shorted to ground:
Measure the resistance between the harness (# 932) sensor connecting terminal and the grounding
(normally, >100kΩ).
Whether the harness open-circuit or shorted to ground?
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
 6-203
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.61 DTC 211104 P2 Pump Pressure Sensor Voltage below the Range Value

Step 3 Check the pump pressure sensor for fault.

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Start the engine, and measure the voltage of No. 932 harness using voltage band of the multimeter with
the boom lifted (normal range 0.5-4.5V) .
Whether the pump pressure sensor fails?
YES NO
Replace the pump pressure sensor
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-204
6.4 Fault Code December 30, 2017
6.4.62 DTC 211203 N1 Negative Flow Pressure Sensor Voltage Above the Range Value CLG930E/936E

6.4.62 DTC 211203 N1 Negative Flow Pressure Sensor Voltage Above the
Range Value

DTC Description Consequence

The N1 negative flow pressure sensor voltage is higher
than the range value. The voltage in the signal circuit of
211203 The complete machine moves slowly.
the N1 negative flow pressure sensor is excessive
(>5V).

System description

The pressure sensor (pressure transmitter) converts the detected hydraulic oil pressure parameter into
the current signal input to the controller which detects the hydraulic oil pressure value which is displayed
on the display instrument.

Pressure sensor parameters:

Output voltage: 0.5-4.5V
Working voltage: 5Vdc
Pressure range: 0-50bar

Component location

Front

N Negative flow
pressure sensor
(position)
 6-205
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.62 DTC 211203 N1 Negative Flow Pressure Sensor Voltage Above the Range Value

Fault diagnosis and troubleshooting steps

Step 1 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Check the connector for moisture, oil dirt or insulation fault.
Whether the connector is faulty?
YES NO
Replace the connector.
Go to Step 4 Go to Step 2

Step 2 Check the harness for short-circuit to battery

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Check the harness (wire No. 919) between the controller (J2-19) and the pump pressure sensor for
wear.
2. Turn the start switch to ON position, and measure the voltage (0.5V normal) between
harness(No.919) sensor end and ground using voltage band of the multimeter.
Whether the harness is shorted to the battery.
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
6-206
6.4 Fault Code December 30, 2017
6.4.62 DTC 211203 N1 Negative Flow Pressure Sensor Voltage Above the Range Value CLG930E/936E

Step 3 Check the N1 negative flow pressure sensor for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Start the engine, and measure the voltage of No. 919 harness using voltage band of the multimeter with
the boom lifted (normal range 0.5-4.5V) .
Whether the N2 negative flow pressure sensor fails?
YES NO
Replace the N1 negative flow pressure sensor.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-207
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.63 DTC 211204 N1 Negative Flow Pressure Sensor Voltage Below the Range Value

6.4.63 DTC 211204 N1 Negative Flow Pressure Sensor Voltage Below the
Range Value

DTC Description Consequence

The N1 negative flow pressure sensor voltage is lower
than the range value. The voltage in the signal circuit of Abnormal hydraulic oil temperature rise under
211204
the N1 negative flow pressure sensor is extremely low no load.
(<0.5V).

System description

The pressure sensor (pressure transmitter) converts the detected hydraulic oil pressure parameter into
the current signal input to the controller which detects the hydraulic oil pressure value which is displayed
on the display instrument.

Pressure sensor parameters:

Output voltage: 0.5-4.5V
Working voltage: 5Vdc
Pressure range: 0-50bar

Component location

Front

N1 Negative flow
pressure sensor
(position)
6-208
6.4 Fault Code December 30, 2017
6.4.63 DTC 211204 N1 Negative Flow Pressure Sensor Voltage Below the Range Value CLG930E/936E

Fault diagnosis and troubleshooting steps

Step 1 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
1. Check the connector at the sensor grounding for poor contact
2. Check whether the connector becomes loose.
3. Check the connector pins for rust, bending or damage.
Whether the connector is faulty?
YES NO
Repair or replace the connector.
Go to Step 4 Go to Step 2

Step 2 Check the harness for open-circuit or short-circuit to ground.

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Check the harness (# 919) between the controller (J2-19) and the pump pressure sensor, the power
line (# 828) for wear.
Turn the start switch to ON position and disconnect the P4 connector.
2. Check the harness for open-circuit:
(1) Turn the multimeter to its voltage function, and measure the voltage between the power line (No.
828) sensor connecting terminal and the grounding (normally, 5V).
(2) Turn the multimeter to its resistance function, and measure the resistance of the harness (# 919)
between the controller and the sensor (normally, <10Ω)
3. Check whether the harness is shorted to ground:
Measure the resistance between the harness (# 919) sensor connecting terminal and the grounding
(normally, >100kΩ).
Whether the harness open-circuit or shorted to ground?
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
 6-209
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.63 DTC 211204 N1 Negative Flow Pressure Sensor Voltage Below the Range Value

Step 3 Check the N1 negative flow pressure sensor for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Start the engine, and measure the voltage of No. 919 harness using voltage band of the multimeter with
the boom lifted (normal range 0.5-4.5V) .
Whether the N1 Negative Flow Pressure Sensor Fails?
YES NO
Replace the N1 negative flow pressure sensor.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-210
6.4 Fault Code December 30, 2017
6.4.64 DTC 211303 N2 Negative Flow Pressure Sensor Voltage Above the Range Value CLG930E/936E

6.4.64 DTC 211303 N2 Negative Flow Pressure Sensor Voltage Above the
Range Value

DTC Description Consequence

The N2 negative flow pressure sensor voltage is higher
than the range value. The voltage in the signal circuit of
211303 The complete machine moves slowly.
the N2 negative flow pressure sensor is excessive
(>5V).

System description

The pressure sensor (pressure transmitter) converts the detected hydraulic oil pressure parameter into
the current signal input to the controller which detects the hydraulic oil pressure value which is displayed
on the display instrument.

Pressure sensor parameters:

Output voltage: 0.5-4.5V
Working voltage: 5Vdc
Pressure range: 0-50bar

Component location

Front

N Negative flow
pressure sensor
(position)
 6-211
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.64 DTC 211303 N2 Negative Flow Pressure Sensor Voltage Above the Range Value

Fault diagnosis and troubleshooting steps

Step 1 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Check the connector for moisture, oil dirt or insulation fault.
Whether the connector is faulty?
YES NO
Repair or replace the connector.
Go to Step 4 Go to Step 2

Step 2 Check the harness for short-circuit to battery

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Check the harness (# 933) between the controller (J2-33) and the N2 negative flow pressure sensor
for wear.
2. Turn the start switch to ON position, and measure the voltage (0.5V normal) between
harness(No.933) sensor end and ground using voltage band of the multimeter.
Whether the harness is shorted to the battery.
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
6-212
6.4 Fault Code December 30, 2017
6.4.64 DTC 211303 N2 Negative Flow Pressure Sensor Voltage Above the Range Value CLG930E/936E

Step 3 Check the N2 negative flow pressure sensor for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Start the engine, and measure the voltage of No. 933 harness using voltage band of the multimeter with
the boom lifted (normal range 0.5-4.5V) .
Whether the N2 negative flow pressure sensor fails?
YES NO
Replace the N2 negative flow pressure sensor.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-213
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.65 DTC 211304 N2 Negative Flow Pressure Sensor Voltage Below the Range Value

6.4.65 DTC 211304 N2 Negative Flow Pressure Sensor Voltage Below the
Range Value

DTC Description Consequence

The N2 negative flow pressure sensor voltage is lower
than the range value. (The voltage in the signal circuit Abnormal hydraulic oil temperature rise under
211304
of the N2 negative flow pressure sensor is extremely no load.
low--<0.5V).

System description

The pressure sensor (pressure transmitter) converts the detected hydraulic oil pressure parameter into
the current signal input to the controller which detects the hydraulic oil pressure value which is displayed
on the display instrument.

Pressure sensor parameters:

Output voltage: 0.5-4.5V
Working voltage: 5Vdc
Pressure range: 0-50bar

Component location

Front

N Negative flow
pressure sensor
(position)
6-214
6.4 Fault Code December 30, 2017
6.4.65 DTC 211304 N2 Negative Flow Pressure Sensor Voltage Below the Range Value CLG930E/936E

Fault diagnosis and troubleshooting steps

Step 1 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
1. Check the connector at the sensor grounding for poor contact
2. Check whether the connector becomes loose.
3. Check the connector pins for rust, bending or damage.
Whether the connector is faulty?
YES NO
Repair or replace the connector.
Go to Step 4 Go to Step 2

Step 2 Check the harness for open-circuit or short-circuit to ground.

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Check the harness (# 933) between the controller (J2-33) and the N2 negative flow pressure sensor
and the power line (# 121) for wear.
Turn the start switch to the ON position, and disconnect the connectors from the N2 negative flow
pressure sensor and the controller.
2. Check the harness for open-circuit:
(1) Turn the multimeter to its voltage function, and measure the voltage between the power line (No.
828) sensor connecting terminal and the grounding (normally, 5V).
(2) Turn the multimeter to its resistance function, and measure the resistance of the harness (# 933)
between the controller and the sensor (normally, <10Ω)
3. Check whether the harness is shorted to ground:
Measure the resistance between the harness (# 933) sensor connecting terminal and the grounding
(normally, >100kΩ).
Whether the harness open-circuit or shorted to ground?
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
 6-215
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.65 DTC 211304 N2 Negative Flow Pressure Sensor Voltage Below the Range Value

Step 3 Check the N2 negative flow pressure sensor for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Start the engine, and measure the voltage of No. 933 harness using voltage band of the multimeter with
the boom lifted (normal range 0.5-4.5V) .
Whether the N2 negative flow pressure sensor fails?
YES NO
Replace the N2 negative flow pressure sensor.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-216
6.4 Fault Code December 30, 2017
6.4.66 DTC 221001 Actuator Feedback Voltage below the Range Value CLG930E/936E

6.4.66 DTC 221001 Actuator Feedback Voltage below the Range Value

DTC Description Consequence

The actuator feedback voltage is lower than the range
221001 value, i.e., the detected voltage in the actuator The accelerator actuator fails.
feedback signal circuit is lower than 4.5V.

System description

The accelerator control system mainly consists of the accelerator potentiometer (accelerator knob),
controller and accelerator actuator. The schematic diagram is shown below: #907 and #904 are drive
control lines. The controller is driven by 2 pins. If either pin is open-circuit, this can cause the accelerator
system fault. The accelerator potentiometer is used to control the engine speed. As shown in the figure,
Pin 1 of the R1 connector is connected to the 5V power, Pin 2 is connected to the controller-sensor
ground terminal and Pin 3 is connected to the accelerator signal feedback terminal. The accelerator
actuator controls the engine accelerator opening through the flexible shaft to control the engine speed.
The terminals are shown in the figure. Pin 3 of the M1 connector is the controller power (5V), pin 5 is
grounded, pin 2 is used for the accelerator feedback signal, pin 1 is used to control the accelerator
motor’s forward rotation and pin 4 is used to control the accelerator motor’s reverse rotation.
 6-217
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.66 DTC 221001 Actuator Feedback Voltage below the Range Value

Component location

Front

Accelerator actuator

Fault diagnosis and troubleshooting steps

Step 1 Check the accelerator actuator for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Disconnect the connectors from the accelerator actuator:
4. Check the connector pins for looseness, rust, bending and damage. Check the connector inside for
moisture, oil dirt and other.
5. Turn the multimeter to its resistance function (20kΩ) and measure the resistance between the
actuator connector pins 3 and 5 (normally, about 4-5kΩ), and then, using the multimeter, measure
the resistance between the pins 2 and 3 and that between the pins 2 and 5. The sum of the
resistance between the pins 2 and 3 and that between the pins 2 and 5 equals the resistance
between the pins 3 and 5.
Whether the accelerator actuator fails?
YES NO
Repair or replace the accelerator actuator.
Go to Step 4 Go to Step 2
6-218
6.4 Fault Code December 30, 2017
6.4.66 DTC 221001 Actuator Feedback Voltage below the Range Value CLG930E/936E

Step 2 Check the harness for open-circuit and short-circuit.

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Check the harness (# 828,# 918) between the controller (J1-28,J1-18) and the accelerator actuator
for wear.
Disconnect the connectors from the accelerator actuator and the controller, respectively
2. Check the harness for open-circuit:
Turn the multimeter to its resistance function, and measure the resistance of the harness (# 828/# 918)
between the controller and the accelerator actuator, respectively, (normally, <10Ω).
3. Check whether the harness is short-circuited to ground:
Turn the multimeter to its resistance function, and measure the resistance between the (# 828/# 918)
harness’s actuator coupling end and the grounding (normally, >100K).
Is the harness open or short circuit ?
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
 6-219
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.66 DTC 221001 Actuator Feedback Voltage below the Range Value

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the actuator connector and disconnect the controller connector. Turn the multimeter to its
resistance function and measure the resistance between the controller port J1-28 and J2-18 (normally,
4~5kΩ), and then measure the resistance between the ports J1-28 and J2-22 and that between the
ports J2-28 and J2-22. The sum of the resistance between the pins 2 and 3 and that between the pins
2 and 5 equals the resistance between the pins 3 and 5.
An abnormal resistance indicates that there is fault in the connector.
Whether the connector is faulty?
YES NO
Replace the connector
Go to Step 4
Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-220
6.4 Fault Code December 30, 2017
6.4.67 DTC 221003 Actuator Feedback Voltage Above the Range Value CLG930E/936E

6.4.67 DTC 221003 Actuator Feedback Voltage Above the Range Value

DTC Description Consequence

The actuator feedback voltage is higher than the range
221003 value, i.e., the detected voltage in the actuator The accelerator actuator fails.
feedback signal circuit is higher than 4.5V.

System description

The accelerator control system mainly consists of the accelerator potentiometer (accelerator knob),
controller and accelerator actuator. The schematic diagram is shown below: #907 and #904 are drive
control lines. The controller is driven by 2 pins. If either pin is open-circuit, this can cause the accelerator
system fault. The accelerator potentiometer is used to control the engine speed. As shown in the figure,
Pin 1 of the R1 connector is connected to the 5V power, Pin 2 is connected to the controller-sensor
ground terminal and Pin 3 is connected to the accelerator signal feedback terminal. The accelerator
actuator controls the engine accelerator opening through the flexible shaft to control the engine speed.
The terminals are shown in the figure. Pin 3 of the M1 connector is the controller power (5V), pin 5 is
grounded, pin 2 is used for the accelerator feedback signal, pin 1 is used to control the accelerator
motor’s forward rotation and pin 4 is used to control the accelerator motor’s reverse rotation.
 6-221
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.67 DTC 221003 Actuator Feedback Voltage Above the Range Value

Component location

Front

Accelerator actuator

Fault diagnosis and troubleshooting steps

Step 1 Check the accelerator actuator for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Disconnect the connectors from the accelerator actuator:
1. Check the connector pins for looseness, rust, bending and damage. Check the connector inside for
moisture, oil dirt and other.
2. Turn the multimeter to its resistance function (20kΩ) and measure the resistance between the
actuator connector pins 3 and 5 (normally, about 4.29kΩ), and then, using the multimeter, measure
the resistance between the pins 2 and 3 and that between the pins 2 and 5. The sum of the
resistance between the pins 2 and 3 and that between the pins 2 and 5 equals the resistance
between the pins 3 and 5.
Whether the accelerator actuator fails?
YES NO
Repair or replace the accelerator actuator.
Go to Step 4 Go to Step 2
6-222
6.4 Fault Code December 30, 2017
6.4.67 DTC 221003 Actuator Feedback Voltage Above the Range Value CLG930E/936E

Step 2 Check the harness for open-circuit and short-circuit.

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Check the harness between the controller and the accelerator actuator for wear.
Disconnect the connectors from the accelerator actuator and the controller, respectively
2. Check whether the harness is shorted to the battery:
Turn the start switch to the ON position and turn on all switches of the electrical equipment, and then
measure the voltage between the harness (# 828/# 904) solenoid valve terminal and the grounding
(normally, 0V), respectively.
3. Check the harness for open-circuit:
Turn the multimeter to its resistance function, and measure the resistance of the harness (# 922)
between the controller port (J2-22) and the solenoid valve (normally, <10Ω).
Is the harness open or short circuit ?
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
 6-223
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.67 DTC 221003 Actuator Feedback Voltage Above the Range Value

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the actuator connector and disconnect the controller connector. Turn the multimeter to its
resistance function and measure the resistance between the controller port J1-28 and J2-18 (normally,
4~5kΩ), and then measure the resistance between the ports J1-28 and J2-22 and that between the
ports J2-28 and J2-22. The sum of the resistance between the pins 2 and 3 and that between the pins
2 and 5 equals the resistance between the pins 3 and 5.
An abnormal resistance indicates that there is fault in the connector.
Whether the connector is faulty?
YES NO
Replace the connector
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-224
6.4 Fault Code December 30, 2017
6.4.68 DTC 221007 Actuator Getting Stuck CLG930E/936E

6.4.68 DTC 221007 Actuator Getting Stuck

DTC Description Consequence

221007 The actuator gets stuck. The accelerator actuator fails.

System description

The accelerator control system mainly consists of the accelerator potentiometer (accelerator knob),
controller and accelerator actuator. The schematic diagram is shown below: #907 and #904 are drive
control lines. The controller is driven by 2 pins. If either pin is open-circuit, this can cause the accelerator
system fault. The accelerator potentiometer is used to control the engine speed. As shown in the figure,
Pin 1 of the R1 connector is connected to the 5V power, Pin 2 is connected to the controller-sensor
ground terminal and Pin 3 is connected to the accelerator signal feedback terminal. The accelerator
actuator controls the engine accelerator opening through the flexible shaft to control the engine speed.
The terminals are shown in the figure. Pin 3 of the M1 connector is the controller power (5V), pin 5 is
grounded, pin 2 is used for the accelerator feedback signal, pin 1 is used to control the accelerator
motor’s forward rotation and pin 4 is used to control the accelerator motor’s reverse rotation.
 6-225
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.68 DTC 221007 Actuator Getting Stuck

Component location

Front

Accelerator actuator

Fault diagnosis and troubleshooting steps

Step 1 Check the harness connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Check the harness connector for looseness.
Check the harness connector pins for rust, bending and damage.
There is moisture, oil dirt or insulation fault in the connector.
Whether a fault developing in the connector or not?
YES NO
Repair or replace the connector.
Go to Step 3 Go to Step 2
6-226
6.4 Fault Code December 30, 2017
6.4.68 DTC 221007 Actuator Getting Stuck CLG930E/936E

Step 2 Check whether the accelerator actuator gets stuck.

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position, and visually check whether the engine accelerator flexible
shaft (including its mounting plate) becomes loose
Start the excavator and turn the accelerator knob, and then check whether the accelerator flexible shaft
is operating properly.
Whether the accelerator actuator gets stuck?
YES NO
Repair or replace the accelerator actuator
Go to Step 3 Go to Step 3

Step 3 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-227
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.69 DTC 221013 Actuator outside the Calibrated Range

6.4.69 DTC 221013 Actuator outside the Calibrated Range

DTC Description Consequence

221013 Actuator outside the calibrated range The accelerator actuator fails.

System description

The accelerator control system mainly consists of the accelerator potentiometer (accelerator knob),
controller and accelerator actuator. The schematic diagram is shown below: #907 and #904 are drive
control lines. The controller is driven by 2 pins. If either pin is open-circuit, this can cause the accelerator
system fault. The accelerator potentiometer is used to control the engine speed. As shown in the figure,
Pin 1 of the R1 connector is connected to the 5V power, Pin 2 is connected to the controller-sensor
ground terminal and Pin 3 is connected to the accelerator signal feedback terminal. The accelerator
actuator controls the engine accelerator opening through the flexible shaft to control the engine speed.
The terminals are shown in the figure. Pin 3 of the M1 connector is the controller power (5V), pin 5 is
grounded, pin 2 is used for the accelerator feedback signal, pin 1 is used to control the accelerator
motor’s forward rotation and pin 4 is used to control the accelerator motor’s reverse rotation.
6-228
6.4 Fault Code December 30, 2017
6.4.69 DTC 221013 Actuator outside the Calibrated Range CLG930E/936E

Component location

Front

Accelerator actuator

Fault diagnosis and troubleshooting steps

Step 1 Check whether the number of teeth of the flywheel is correct.

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Check whether the number of teeth of the flywheel is correct in the control parameter.
Whether the number of teeth of the flywheel is correct or not?
YES NO
Re-adjust the number of teeth of the flywheel in the
control parameter.
Go to Step 6 Go to Step 2
 6-229
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.69 DTC 221013 Actuator outside the Calibrated Range

Step 2 Check the speed sensor for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
1. Check the sensor for looseness.
2. Disconnect the speed sensor connector:
(1) Check the connector pins for looseness, rust, bending and damage. Check the connector inside for
moisture, oil dirt and other.
(2) Start the engine and turn the knob to increase the accelerator gradually. Turn the multimeter to its
AC voltage function, and measure the voltage on the sensor output ports (normally, when the
engine speed at 1000~2270r/min, the speed sensor outputs an AC voltage between 3~28V).
Whether the speed sensor is faulty?
YES NO
Tighten or repair, or replace the speed sensor.
Go to Step 6 Go to Step 3

Step 3 Check the harness for short-circuit

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Check the harness (# 918) between the controller (J2-18)and the accelerator actuator for wear.
2. Disconnect the connectors from the accelerator actuator and the controller, respectively. Turn the
multimeter to its resistance function, and then measure the resistance between the harness (# 918)
actuator terminal and the grounding (normally, >100K).
Is the harness short-circuit?
YES NO
Connect the harness again and wrap the harness
Go to Step 4
Go to Step 6
6-230
6.4 Fault Code December 30, 2017
6.4.69 DTC 221013 Actuator outside the Calibrated Range CLG930E/936E

Step 4 Check whether the harness is open-circuited or shorted to the battery.

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
Disconnect the connectors from the accelerator actuator and the controller, respectively
1. Check the harness for open-circuit: Turn the multimeter to its resistance function, and measure the
resistance of the harness (# 918) between the controller and the actuator (normally, <10Ω).
2. Check whether the harness is shorted to the battery. Turn the start switch to the ON position and
turn on all switches of the electrical equipment, and then measure the voltage between the harness
(#918) actuator terminal and the grounding (normally, 0V).
Whether the harness open-circuited or shorted to the battery or not?
YES NO
Connect the harness again and wrap the harness
Go to Step 6 Go to Step 5

Step 5 Check whether the harness is connected wrong.

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method

According to the accelerator control system schematics, check whether the sequence of the
harnesses between the actuator and the controller is correct.
Whether the harness is connected wrong or not.
YES NO
Connect the harness again and wrap the harness
Go to Step 6 Go to Step 6
 6-231
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.69 DTC 221013 Actuator outside the Calibrated Range

Step 6 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-232
6.4 Fault Code December 30, 2017
6.4.70 DTC 221104 Actuator AC1 Shorted to Ground CLG930E/936E

6.4.70 DTC 221104 Actuator AC1 Shorted to Ground

DTC Description Consequence

The actuator fails to work, so the revolving
221104 AC1 end of actuator short circuit to ground
speed cannot be governed.

System description

The accelerator control system mainly consists of the accelerator potentiometer (accelerator knob),
controller and accelerator actuator. The schematic diagram is shown below: #907 and #904 are drive
control lines. The controller is driven by 2 pins. If either pin is open-circuit, this can cause the accelerator
system fault. The accelerator potentiometer is used to control the engine speed. As shown in the figure,
Pin 1 of the R1 connector is connected to the 5V power, Pin 2 is connected to the controller-sensor
ground terminal and Pin 3 is connected to the accelerator signal feedback terminal. The accelerator
actuator controls the engine accelerator opening through the flexible shaft to control the engine speed.
The terminals are shown in the figure. Pin 3 of the M1 connector is the controller power (5V), pin 5 is
grounded, pin 2 is used for the accelerator feedback signal, pin 1 is used to control the accelerator
motor’s forward rotation and pin 4 is used to control the accelerator motor’s reverse rotation.
 6-233
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.70 DTC 221104 Actuator AC1 Shorted to Ground

Component location

Front

Accelerator actuator

Fault diagnosis and troubleshooting steps

Step 1 Check the accelerator actuator for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position and disconnect the accelerator actuator connectors:
1. Check the connector for looseness, rust, bending and damage.
2. Measure the resistance between the accelerator actuator connector terminals 1 and 4 using
multimeter resistance function (normally, <100kΩ).
Whether the accelerator actuator fails?
YES NO
Repair or replace the accelerator actuator.
Go to Step 4 Go to Step 2

Step 2 Check the harness for short-circuit

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Check the harness (# 907) between the controller (J2-07)and the accelerator actuator for wear.
2. Disconnect the connectors from the accelerator actuator and the controller, respectively. Turn the
multimeter to its resistance function, and then measure the resistance between the harness (# 907)
actuator terminal and the grounding (normally, >100K).
6-234
6.4 Fault Code December 30, 2017
6.4.70 DTC 221104 Actuator AC1 Shorted to Ground CLG930E/936E

Is the harness short-circuit?

YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the accelerator actuator connector and disconnect the controller connector. Turn the
multimeter to its resistance function, and measure the resistance between the controller port J2-07 and
the grounding (normally, >100K).
When the resistance is abnormal, this indicates there is an insulation fault in the connector
Whether the connector is faulty?
YES NO
Replace the connector
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-235
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.71 DTC 221204 Actuator AC2 Shorted to Ground

6.4.71 DTC 221204 Actuator AC2 Shorted to Ground

DTC Description Consequence

The actuator fails to work, so the revolving
221204 AC end 2 of actuator short circuit to ground
speed cannot be governed.

System description

The accelerator control system mainly consists of the accelerator potentiometer (accelerator knob),
controller and accelerator actuator. The schematic diagram is shown below: #907 and #904 are drive
control lines. The controller is driven by 2 pins. If either pin is open-circuit, this can cause the accelerator
system fault. The accelerator potentiometer is used to control the engine speed. As shown in the figure,
Pin 1 of the R1 connector is connected to the 5V power, Pin 2 is connected to the controller-sensor
ground terminal and Pin 3 is connected to the accelerator signal feedback terminal. The accelerator
actuator controls the engine accelerator opening through the flexible shaft to control the engine speed.
The terminals are shown in the figure. Pin 3 of the M1 connector is the controller power (5V), pin 5 is
grounded, pin 2 is used for the accelerator feedback signal, pin 1 is used to control the accelerator
motor’s forward rotation and pin 4 is used to control the accelerator motor’s reverse rotation.
6-236
6.4 Fault Code December 30, 2017
6.4.71 DTC 221204 Actuator AC2 Shorted to Ground CLG930E/936E

Component location

Front

Accelerator actuator

Fault diagnosis and troubleshooting steps

Step 1 Check the accelerator actuator for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position and disconnect the accelerator actuator connectors:
1. Check the connector for looseness, rust, bending and damage.
2. Turn the multimeter to its resistance function, and measure the resistance between the actuator
connector terminal 1 and the grounding (normally, >100kΩ)
Whether the accelerator actuator fails?
YES NO
Repair or replace the accelerator actuator.
Go to Step 4 Go to Step 2

Step 2 Check the harness for short-circuit

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Check the harness (#904) between the controller (J2-04) and the accelerator actuator for wear.
2. Disconnect the connectors from the accelerator actuator and the controller, respectively. Turn the
multimeter to its resistance function, and then measure the resistance between the harness (# 904)
actuator terminal and the grounding (normally, >100K).
 6-237
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.71 DTC 221204 Actuator AC2 Shorted to Ground

Is the harness short-circuit?

YES NO
Connect the harness again and wrap the harness
Go to Step 3
Go to Step 4
Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the accelerator actuator connector and disconnect the controller connector. Turn the
multimeter to its resistance function, and measure the resistance between the controller port J2-04 and
the grounding (normally, >100K).
When the resistance is abnormal, this indicates there is an insulation fault in the connector
Whether the connector is faulty?
YES NO
Replace the connector
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-238
6.4 Fault Code December 30, 2017
6.4.72 DTC 221305 Actuator AC1 Open-Circuited CLG930E/936E

6.4.72 DTC 221305 Actuator AC1 Open-Circuited

DTC Description Consequence

221305 AC1 end of actuator open circuit The actuator fails to work.

System description

The accelerator control system mainly consists of the accelerator potentiometer (accelerator knob),
controller and accelerator actuator. The schematic diagram is shown below: #907 and #904 are drive
control lines. The controller is driven by 2 pins. If either pin is open-circuit, this can cause the accelerator
system fault. The accelerator potentiometer is used to control the engine speed. As shown in the figure,
Pin 1 of the R1 connector is connected to the 5V power, Pin 2 is connected to the controller-sensor
ground terminal and Pin 3 is connected to the accelerator signal feedback terminal. The accelerator
actuator controls the engine accelerator opening through the flexible shaft to control the engine speed.
The terminals are shown in the figure. Pin 3 of the M1 connector is the controller power (5V), pin 5 is
grounded, pin 2 is used for the accelerator feedback signal, pin 1 is used to control the accelerator
motor’s forward rotation and pin 4 is used to control the accelerator motor’s reverse rotation.
 6-239
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.72 DTC 221305 Actuator AC1 Open-Circuited

Component location

Front

Accelerator actuator

Fault diagnosis and troubleshooting steps

Step 1 Check the accelerator actuator for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position and disconnect the accelerator actuator connectors:
1. Check the connector for looseness, rust, bending and damage.
2. Measure the resistance between the accelerator actuator connector terminals 1 and 4 using
multimeter resistance function (normally, <100kΩ).
Whether the accelerator actuator fails?
YES NO
Repair or replace the accelerator actuator.
Go to Step 4 Go to Step 2

Step 2 Check the harness for open-circuit

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
6-240
6.4 Fault Code December 30, 2017
6.4.72 DTC 221305 Actuator AC1 Open-Circuited CLG930E/936E

Inspection method
1. Check the connecting harness (#907/904) between the controller and the accelerator actuator for
wear.
2. Disconnect the connectors from the accelerator actuator and the controller, respectively. Measure
the resistance value of the connecting harness (#907/904) between the controller and the actuator
using multimeter resistance function (normally, <10Ω).
Is the harness open-circuit?
YES NO
Connect the harness again and wrap the harness
Go to Step 3
Go to Step 4
Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the accelerator actuator connector and disconnect the controller connector. Turn the
multimeter to its resistance function, and measure the resistance between the controller port J2-07
harness and J2-04 (normally, <100K).
When the resistance is abnormal, this indicates the connector is poorly contacted.
Whether the connector is faulty?
YES NO
Replace the connector
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-241
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.73 DTC 221306 Actuator AC1 Overcurrent

6.4.73 DTC 221306 Actuator AC1 Overcurrent

DTC Description Consequence

Actuator AC1 overcurrent (actuator AC1 terminal is
The actuator fails to work, so the revolving
221306 shorted to the battery, with a 3Ω circuit connected in
speed cannot be governed.
series.)

System description

The accelerator control system mainly consists of the accelerator potentiometer (accelerator knob),
controller and accelerator actuator. The schematic diagram is shown below: #907 and #904 are drive
control lines. The controller is driven by 2 pins. If either pin is open-circuit, this can cause the accelerator
system fault. The accelerator potentiometer is used to control the engine speed. As shown in the figure,
Pin 1 of the R1 connector is connected to the 5V power, Pin 2 is connected to the controller-sensor
ground terminal and Pin 3 is connected to the accelerator signal feedback terminal. The accelerator
actuator controls the engine accelerator opening through the flexible shaft to control the engine speed.
The terminals are shown in the figure. Pin 3 of the M1 connector is the controller power (5V), pin 5 is
grounded, pin 2 is used for the accelerator feedback signal, pin 1 is used to control the accelerator
motor’s forward rotation and pin 4 is used to control the accelerator motor’s reverse rotation.
6-242
6.4 Fault Code December 30, 2017
6.4.73 DTC 221306 Actuator AC1 Overcurrent CLG930E/936E

Component location

Front

Accelerator actuator

Fault diagnosis and troubleshooting steps

Step 1 Check the accelerator actuator for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position and disconnect the accelerator actuator connectors:
1. Check the connector for looseness, rust, bending and damage.
2. Measure the resistance between the accelerator actuator connector terminals 1 and 4 using
multimeter resistance function (normally, <10kΩ).
Whether the accelerator actuator fails?
YES NO
Repair or replace the accelerator actuator.
Go to Step 4 Go to Step 2

Step 2 Check whether the harness is shorted to the battery.

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
 6-243
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.73 DTC 221306 Actuator AC1 Overcurrent

Inspection method
1. Check the harness (#907/#904) between the controller (J2-07 ,J7-04)and the accelerator actuator
for wear respectively.
Disconnect both the controller and the solenoid valve
2. Check the two harnesses for short-circuit: Turn the multimeter to its resistance function, and
measure the resistance of the harness (#907/#904) between the actuator terminals (normally,
>100K).
3. Check whether the harness is shorted to the battery. Turn the start switch to the ON position and
switch off the switches of all electrical equipment, and then measure the voltage between the
harness (#907/#904) actuator connecting terminal and the grounding (normally, 0V).
Whether the harness is shorted to the battery.
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the accelerator actuator connector and disconnect the controller connector. Turn the
multimeter to its resistance function, and measure the resistance between the controller port J2-07 and
J2-04 (normally, >10Ω).
When the resistance is abnormal, this indicates there is an insulation fault in the connector
Whether the connector is faulty?
YES NO
Replace the connector
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-244
6.4 Fault Code December 30, 2017
6.4.74 DTC 221405 Actuator AC2 Terminal Open-Circuited CLG930E/936E

6.4.74 DTC 221405 Actuator AC2 Terminal Open-Circuited

DTC Description Consequence

221405 AC2end of actuator open circuit The actuator fails to work.

System description

The accelerator control system mainly consists of the accelerator potentiometer (accelerator knob),
controller and accelerator actuator. The schematic diagram is shown below: #907 and #904 are drive
control lines. The controller is driven by 2 pins. If either pin is open-circuit, this can cause the accelerator
system fault. The accelerator potentiometer is used to control the engine speed. As shown in the figure,
Pin 1 of the R1 connector is connected to the 5V power, Pin 2 is connected to the controller-sensor
ground terminal and Pin 3 is connected to the accelerator signal feedback terminal. The accelerator
actuator controls the engine accelerator opening through the flexible shaft to control the engine speed.
The terminals are shown in the figure. Pin 3 of the M1 connector is the controller power (5V), pin 5 is
grounded, pin 2 is used for the accelerator feedback signal, pin 1 is used to control the accelerator
motor’s forward rotation and pin 4 is used to control the accelerator motor’s reverse rotation.
 6-245
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.74 DTC 221405 Actuator AC2 Terminal Open-Circuited

Component location

Front

Accelerator actuator

Fault diagnosis and troubleshooting steps

Step 1 Check the accelerator actuator for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position and disconnect the accelerator actuator connectors:
1. Check the connector for looseness, rust, bending and damage.
2. Measure the resistance between the accelerator actuator connector terminals 1 and 4 using
multimeter resistance function (normally, <100kΩ).
Whether the accelerator actuator fails?
YES NO
Repair or replace the accelerator actuator.
Go to Step 4 Go to Step 2

Step 2 Check the harness for open-circuit

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
6-246
6.4 Fault Code December 30, 2017
6.4.74 DTC 221405 Actuator AC2 Terminal Open-Circuited CLG930E/936E

Inspection method
1. Check the connecting harness (#907/904) between the controller and the accelerator actuator for
wear.
2. Disconnect the connectors from the accelerator actuator and the controller, respectively. Measure
the resistance value of the connecting harness (#907/904) between the controller and the actuator
using multimeter resistance function (normally, <10Ω).
Is the harness open-circuit?
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the accelerator actuator connector and disconnect the controller connector. Turn the
multimeter to its resistance function, and measure the resistance between the controller port J2-07
harness and J2-04 (normally, <100K).
When the resistance is abnormal, this indicates the connector is poorly contacted.
Whether the connector is faulty?
YES NO
Replace the connector
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-247
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.75 DTC 221406 Actuator AC2 Overcurrent

6.4.75 DTC 221406 Actuator AC2 Overcurrent

DTC Description Consequence

Actuator AC2 overcurrent (actuator AC2 terminal is The actuator fails to work, so the revolving
221406
shorted to the battery). speed cannot be governed.

System description

The accelerator control system mainly consists of the accelerator potentiometer (accelerator knob),
controller and accelerator actuator. The schematic diagram is shown below: #907 and #904 are drive
control lines. The controller is driven by 2 pins. If either pin is open-circuit, this can cause the accelerator
system fault. The accelerator potentiometer is used to control the engine speed. As shown in the figure,
Pin 1 of the R1 connector is connected to the 5V power, Pin 2 is connected to the controller-sensor
ground terminal and Pin 3 is connected to the accelerator signal feedback terminal. The accelerator
actuator controls the engine accelerator opening through the flexible shaft to control the engine speed.
The terminals are shown in the figure. Pin 3 of the M1 connector is the controller power (5V), pin 5 is
grounded, pin 2 is used for the accelerator feedback signal, pin 1 is used to control the accelerator
motor’s forward rotation and pin 4 is used to control the accelerator motor’s reverse rotation.
6-248
6.4 Fault Code December 30, 2017
6.4.75 DTC 221406 Actuator AC2 Overcurrent CLG930E/936E

Component location

Front

Accelerator actuator

Fault diagnosis and troubleshooting steps

Step 1 Check the accelerator actuator for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to the OFF position and disconnect the accelerator actuator connectors:
1. Check the connector for looseness, rust, bending and damage.
2. Measure the resistance between the accelerator actuator connector terminals 1 and 4 using
multimeter resistance function (normally, <10kΩ).
Whether the accelerator actuator fails?
YES NO
Repair or replace the accelerator actuator.
Go to Step 4 Go to Step 2

Step 2 Check whether the harness is shorted to the battery.

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
 6-249
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.75 DTC 221406 Actuator AC2 Overcurrent

Inspection method
1. Check the harness (#907/#904) between the controller (J2-07 ,J7-04)and the accelerator actuator
for wear respectively.
Disconnect both the controller and the solenoid valve
2. Check the two harnesses for short-circuit: Turn the multimeter to its resistance function, and
measure the resistance of the harness (#907/#904) between the actuator terminals (normally,
>100K).
3. Check whether the harness is shorted to the battery. Turn the start switch to the ON position and
switch off the switches of all electrical equipment, and then measure the voltage between the
harness (#907/#904) actuator connecting terminal and the grounding (normally, 0V).
Whether the harness is shorted to the battery.
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the accelerator actuator connector and disconnect the controller connector. Turn the
multimeter to its resistance function, and measure the resistance between the controller port J2-07 and
J2-04 (normally, >10Ω).
When the resistance is abnormal, this indicates there is an insulation fault in the connector
Whether the connector is faulty?
YES NO
Replace the connector
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-250
6.4 Fault Code December 30, 2017
6.4.76 DTC 231012 Abnormal Controller Heartbeat CLG930E/936E

6.4.76 DTC 231012 Abnormal Controller Heartbeat

DTC Description Consequence

231012 Abnormal controller heartbeat. The machine fails to work

System description

The controller is the core part of the excavator’s electrical control system and is responsible for the
complete machine operation mode and status, information processing, and various electronic control
functions.

Component location

Controller

Controller connector
Front
 6-251
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.76 DTC 231012 Abnormal Controller Heartbeat

Fault diagnosis and troubleshooting steps

Step 1 Check the controller connector J1 for looseness

Inspection method
Manually check whether the controller connector for looseness or fall-off.
Whether the controller connector J1 becomes loose or not?
YES NO
Repair or tighten the connector.
Go to Step 3 Go to Step 2

Step 2 Check whether there is no power to the controller.

Inspection method
Dismantle the controller connector J1 (black)
Turn the multimeter to its voltage function, and measure the voltage between port 2, 3, 4, 5 & 6 of J1
and the ground, respectively. The voltage should be about 24V, otherwise, the controller power is not
sufficient.
Whether there is no power to the controller?
YES NO
Re-connect the harness
Go to Step 3 Go to Step 3

Step 3 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-252
6.4 Fault Code December 30, 2017
6.4.77 DTC 231014 CAN Bus Communication Error CLG930E/936E

6.4.77 DTC 231014 CAN Bus Communication Error

DTC Description Consequence

231014 CAN bus communication error. The machine fails to work

System description

The CAN bus can achieve real-time data exchange of various control units of the excavator.

Component location

GPS antenna

Display

GPS
 6-253
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.77 DTC 231014 CAN Bus Communication Error

Fault diagnosis and troubleshooting steps

Step 1 Check the controller connector J1 for looseness

Inspection method
Manually check whether the controller connector for looseness or fall-off.
Whether the controller connector J1 becomes loose or not?
YES NO
Repair or tighten the connector.
Go to Step 3 Go to Step 2

Step 2 Check the display harness for fault.

Inspection method
Dismantle the display connector C4 and the GPS connector C3.
Turn the multimeter to its on-off function, and check the harness (#751/# 752) between the port 5 (C3)
and the port 1 (C4)/between the port 8 (C3) and the port 8 (C4) for open-circuit.
Whether the display harness fails?
YES NO
Re-connect the harness
Go to Step 3 Go to Step 3

Step 3 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-254
6.4 Fault Code December 30, 2017
6.4.78 DTC 241014 Accelerator Knob outside the Measurement Range CLG930E/936E

6.4.78 DTC 241014 Accelerator Knob outside the Measurement Range

DTC Description Consequence

Accelerator knob outside the measurement
241014 The gear positions display abnormally.
range

System description

The accelerator control system is mainly composed of accelerator potentiometer(accelerator knob) ,

controller and engine. Schematic: 828 is 5V power line, and 829 is accelerator position signal line, rotate
the accelerator knob clockwise and 829 outputs 0.5-4.5V power supply. Controller control engine
revolving speed according to received voltage signal.

Component location

Throttle Potentiometer

Controller
 6-255
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.78 DTC 241014 Accelerator Knob outside the Measurement Range

Fault diagnosis and troubleshooting steps

Step 1 Check for accelerator knob failure

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
1. Check the connector pins for looseness, rust, bending and damage. Check the connector inside for
moisture, oil dirt and other.
2. Turn the start switch to ON position, and measure the voltage (5V normal) of No.828 harness using
20V voltage band of the multimeter.
3. Turn the start switch to ON position, and measure the voltage of No.829 harness using 20V voltage
band of the multimeter, rotate the accelerator knob gradually from 1-12 position and measure the
voltage output of No.829 harness.
Whether the accelerator knob fails?
YES NO
Repair or replace the accelerator knob.
Go to Step 4 Go to Step 2
Step 2 Check the harness for short-circuit and open-circuit

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Check the harness (No. 828/No. 829) between the controller (J1-28/J1-29) and the accelerator
actuator and the grounding wire (No. 922) for wear.
2. Check whether the harness is shorted to the battery:
Disconnect the connector R1 for the accelerator knob and the controller. Turn the multimeter to its
voltage function, and measure the voltage respectively between the harness No. 828/No. 829 and the
grounding (normally 0V).
3. Check the harness for open-circuit:
Turn the multimeter to its resistance function, and measure the resistance between the (#922) harness
actuator connecting terminal and the grounding (normally, <100kΩ).
Is the harness short-circuit or open-circuit?
YES NO
Connect the harness again and wrap the harness.
Go to Step 4 Go to Step 3
6-256
6.4 Fault Code December 30, 2017
6.4.78 DTC 241014 Accelerator Knob outside the Measurement Range CLG930E/936E

Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the actuator connector and disconnect the controller connector:
1. Turn the multimeter to its resistance function, and measure the resistance between the controller
port J1-28 and the grounding (normally, 4-5kΩ).
2. Turn the multimeter to its resistance function, and measure the resistance between the controller
ports J1-28 and J1-29 (normally, >10Ω).
An abnormal resistance indicates that there is fault in the connector.
Whether the connector is faulty?
YES NO
Replace the connector.
Go to Step 4 Go to Step 4
Step 4 Check whether this fault is eliminated
Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-257
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.79 DTC 251004 Fuel Pump Relay Shorted to Ground

6.4.79 DTC 251004 Fuel Pump System description

Relay Shorted to Ground Power on the electric lock to energize the battery
relay, the harness (No. 133) and the harness
(No. 320), so that the fuel pump can operate. If
DTC Description Consequence
the 6th port of the controller J2 gives the signal
The refueling pump and the harness (No. 906) is energized, then the
Fuel pump relay automatically stops fuel pump relay is energized, so that the
251004
shorted to ground and refueling
harnesses (No. 133 and No. 320) are open-
function fails
circuited and the fuel pump automatically stops.

K12
6-258
6.4 Fault Code December 30, 2017
6.4.79 DTC 251004 Fuel Pump Relay Shorted to Ground CLG930E/936E

Component location

Open the fuse box.

K11 auto preheating

relay. It can be pulled out
during detection.

Attached drawing

Controller

Controller connector
Front
 6-259
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.79 DTC 251004 Fuel Pump Relay Shorted to Ground

Fault diagnosis and troubleshooting steps

Step 1 Check whether the harness connecting the controller port J2-6 is shorted to ground

Notice: Shutdown operation is needed

Inspection method
Turn the start switch to the OFF position for fault diagnosis
Disconnect the connector from the controller (in the figure ) and pull out the fuel refueling pump relay,
and then measure the resistance between the harness (#906) at the J2-6 port and the grounding. The
resistance should be infinite.

Definition of
connector pin
serial number

Whether the harness connecting the controller port J2-6 is shorted to ground?
YES NO
Re-connect the harness, and wrap it.
Go to Step 3 Go to Step 2
6-260
6.4 Fault Code December 30, 2017
6.4.79 DTC 251004 Fuel Pump Relay Shorted to Ground CLG930E/936E

Step 2 Check the connectors for fault

Notice: Shutdown operation is needed

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Check manually the connectors between the relay and the controller one by one for moisture, oil dirt
and other which may cause electric leakage.
Whether the connector fails?
YES NO
Adjust or replace the connector.
Go to Step 3 Go to Step 3

Step 3 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-261
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.80 DTC 251005 Fuel Pump Relay Open-Circuited or Shorted to the Battery

6.4.80 DTC 251005 Fuel Pump System description

Relay Open-Circuited or Shorted Power on the electric lock to energize the battery
to the Battery relay, the harness (No. 133) and the harness
(No. 320), so that the fuel pump can operate. If
the 6th port of the controller J2 gives the signal
DTC Description Consequence and the harness (No. 906) is energized, then the
Fuel refueling pump The refueling pump fuel pump relay is energized, so that the
relay is open-circuited automatically stops harnesses (No. 133 and No. 320) are open-
251005
or shorted to the and refueling circuited and the fuel pump automatically stops.
battery. function fails.

K12
6-262
6.4 Fault Code December 30, 2017
6.4.80 DTC 251005 Fuel Pump Relay Open-Circuited or Shorted to the Battery CLG930E/936E

Component location

Open the fuse box.

K11 auto preheating

relay. It can be pulled out
during detection.

Attached drawing

Controller

Controller connector
Front
 6-263
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.80 DTC 251005 Fuel Pump Relay Open-Circuited or Shorted to the Battery

Fault diagnosis and troubleshooting steps

Step 1 Check the fuel pump relay for fault

Notice: Shutdown operation is needed

Inspection method
Turn the multimeter to its resistance function and measure the resistance between the terminals 85 and
86 of the fuel pump relay coil. The resistance should be between 320-360Ω.
Turn the multimeter to its on/off function, and measure the terminals 30 and 87A of the relay. The relay
should switch on and sound. Connect the ports 85 and 86 to the power supply (24V), and measure the
ports 30 and 87A. The relay should switch off and not sound.
Whether the fuel pump relay fails or not?
YES NO
Replace the relay.
Go to Step 4 Go to Step 2

Step 2 Check the harness for open-circuit

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
Turn the start switch to the OFF position for fault diagnosis.
Disconnect the connector from the controller (in the figure) and pull out the fuel pump relay, and then
measure the resistance between the harness (#906) at the J2-6 port and the fuel pump relay. The
maximum resistance should be 10Ω. Measure the resistance between the 85 port in the fuse box and
the ground. Normally, the resistance should be less than 10Ω.

Definition of
connector pin
serial number
6-264
6.4 Fault Code December 30, 2017
6.4.80 DTC 251005 Fuel Pump Relay Open-Circuited or Shorted to the Battery CLG930E/936E

Is the harness open-circuit?

YES NO
Re-connect the harness, and wrap it.
Go to Step 4 Go to Step 3
Step 3 Check the connector for fault

Notice: Shutdown operation is needed

Inspection method
Insert the fuel pump relay into the fuse box properly and disconnect the controller connector, and then
turn the multimeter to its resistance function and measure the resistance between the harness (# 906)
at the controller port J2-6 and the grounding. The resistance should be between 320-360Ω. Otherwise,
check the connector:
1. Check the connector at the relay grounding for poor contact
2. Check the relay connector for looseness or damage.
Whether the connector fails?
YES NO
Adjust or replace the connector.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-265
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.81 DTC 261011 GPS Antenna Fault

6.4.81 DTC 261011 GPS Antenna Fault

DTC Description Consequence

The machine cannot be positioned and connected
261011 GPS antenna fails
to the monitoring center.

System description

Use the GPS (Global Positioning System) to position the machine and use the GSM mobile
communication network to achieve the two-way data exchange with the central control center to realize
remote monitoring and control.

Component location

GPS antenna

Display

GPS

Fault diagnosis and troubleshooting steps

Step 1 Check the antenna connector for looseness and fall-off

Inspection method
Manually check whether the antenna connector becomes loose or falls off.
Whether the antenna connector becomes loose or falls off?
YES NO
Tighten the antenna connector.
Go to Step 3 Go to Step 2
6-266
6.4 Fault Code December 30, 2017
6.4.81 DTC 261011 GPS Antenna Fault CLG930E/936E

Step 2 Check the antenna for damage.

Inspection method
Remove the antenna, and re-install a new one to determine whether the antenna is damaged.
Whether the antenna is damaged or not?
YES NO
Replace the antenna.
Go to Step 3 Go to Step 3
Step 3 Check whether this fault is eliminated
Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-267
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.82 DTC 261111 GPS Module Fault

6.4.82 DTC 261111 GPS Module Fault

DTC Description Consequence

261111 GPS module fault GPS signals cannot be received.

System description

Use the GPS (Global Positioning System) to position the machine and use the GSM mobile
communication network to achieve the two-way data exchange with the central control center to realize
remote monitoring and control.

Component location

GPS antenna

Display

GPS

Fault diagnosis and troubleshooting steps

Step - Contact local LiuGong dealers and authorized service centers.

6-268
6.4 Fault Code December 30, 2017
6.4.83 DTC 261211 GSM Signal Fault CLG930E/936E

6.4.83 DTC 261211 GSM Signal Fault

DTC Description Consequence

261211 GSM signal fault GSM signal is weak

System description

Use the GPS (Global Positioning System) to position the machine and use the GSM mobile
communication network to achieve the two-way data exchange with the central control center to realize
remote monitoring and control.

Component location

GPS antenna

Display

GPS

Fault diagnosis and troubleshooting steps

Step 1 Check the antenna connector for looseness and fall-off

Inspection method
Manually check whether the antenna connector becomes loose or falls off.
Whether the antenna connector becomes loose or falls off?
YES NO
Tighten the antenna connector.
Go to Step 3 Go to Step 2
 6-269
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.84 DTC 261311 GPRS Connection Fault

Step 2 Check the antenna for damage.

Inspection method
View the mobile signal strength. Compared with the GSM signal, if the mobile signal is stronger, the
antenna is faulty.
Whether the antenna is damaged or not?
YES NO
Replace the antenna.
Go to Step 3 Go to Step 3
Step 3 Check whether this fault is eliminated
Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.

6.4.84 DTC 261311 GPRS Connection Fault

DTC Description Consequence

261311 GPRS connection fault GPS cannot operate properly.

System description

GPRS is used to transmit information between GPS and mobile server.

Fault diagnosis and troubleshooting steps

Step - Contact local LiuGong dealers and authorized service centers.

6-270
6.4 Fault Code December 30, 2017
6.4.85 DTC 261411 SIM Card Read Fault CLG930E/936E

6.4.85 DTC 261411 SIM Card Read Component location

Fault
GPS antenna
DTC Description Consequence
Display
GPS cannot operate
261411 SIM card read fault
properly.

System description GPS

The GPS positioning information is transmitted to

the monitoring center through the SIM card.

Fault diagnosis and troubleshooting steps

Step 1 Check whether the SIM card becomes loose.

Inspection method
Turn the start switch to the OFF position, and manually check whether the SIM card becomes loose.
If the SIM card becomes loose?
YES NO
Fix the SIM card.
Go to Step 2 Go to Step 2

Step 2 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-271
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.86 DTC 261512 Abnormal GPS Heartbeat

6.4.86 DTC 261512 Abnormal GPS Heartbeat

DTC Description Consequence

261512 Abnormal GPS heartbeat Over time, the machine is limited to be used.

System description

Use the GPS (Global Positioning System) to position the machine and use the GSM mobile
communication network to achieve the two-way data exchange with the central control center to realize
remote monitoring and control.
6-272
6.4 Fault Code December 30, 2017
6.4.86 DTC 261512 Abnormal GPS Heartbeat CLG930E/936E

Component location

GPS antenna

Display

GPS

Fault diagnosis and troubleshooting steps

Step 1 Check whether the GPS connector becomes loose and falls off.

Inspection method
Manually check the GPS connector for looseness or fall-off
Whether the GPS connector becomes loose and falls off?
YES NO
Tighten the GPS connector.
Go to Step 3 Go to Step 2

Step 2 Check the harness (No. 149) for fault.

Inspection method
Turn the start switch to the ON position.
Dismantle the GPS connector C3. Make sure no pin of the connector is bent. Turn the multimeter to its
voltage function, and measure the voltage between the connector terminal 4 and the grounding. The
voltage should be 24V. Otherwise, a fault develops in the harness (No. 149).
Whether the power cable has fault?
YES NO
Rewire.
Go to Step 3 Go to Step 3
 6-273
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.86 DTC 261512 Abnormal GPS Heartbeat

Step 3 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
6-274
6.4 Fault Code December 30, 2017
6.4.87 DTC 261611 Automatic Locking Level 1 Abnormal GPS Heartbeat, the Machine is Limited for Use

6.4.87 DTC 261611 Automatic Locking Level 1 Abnormal GPS Heartbeat,

the Machine is Limited for Use

DTC Description Consequence

Automatic locking level 1 abnormal GPS heartbeat, the
261611 The excavator is restricted for use
machine is limited for use

System description

Use the GPS (Global Positioning System) to position the machine and use the GSM mobile
communication network to achieve the two-way data exchange with the central control center to realize
remote monitoring and control.
 6-275
December 30, 2017 6.4 Fault Code
CLG930E/936E 6.4.87 DTC 261611 Automatic Locking Level 1 Abnormal GPS Heartbeat, the Machine is

Component location

GPS antenna

Display

GPS

Fault diagnosis and troubleshooting steps

Step 1 Check whether the GPS connector becomes loose and falls off.

Inspection method
Manually check the GPS connector for looseness or fall-off
Whether the GPS connector becomes loose and falls off?
YES NO
Tighten the GPS connector.
Go to Step 3 Go to Step 2

Step 2 Check the harness (No. 149) for fault.

Inspection method
Turn the start switch to the ON position.
Dismantle the GPS connector C3. Make sure no pin of the connector is bent. Turn the multimeter to its
voltage function, and measure the voltage between the connector terminal 4 and the grounding. The
voltage should be 24V. Otherwise, a fault develops in the harness (No. 149).
Whether the power cable has fault?
YES NO
Rewire.
Go to Step 3 Go to Step 3
6-276
6.4 Fault Code December 30, 2017
6.4.87 DTC 261611 Automatic Locking Level 1 Abnormal GPS Heartbeat, the Machine is Limited for Use

Step 3 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-277
December 30, 2017 6.4 Fault Code
CLG930E/936E6.4.88 DTC 261614 Forced Locking Level 1 Payment Expired, the Machine is Limited for Use

6.4.88 DTC 261614 Forced Locking Level 1 Payment Expired, the

Machine is Limited for Use

DTC Description Consequence

Forced locking level 1 payment expired, and the
261614 The excavator is restricted for use
machine is prohibited for use.

System description

Use the GPS (Global Positioning System) to position the machine and use the GSM mobile
communication network to achieve the two-way data exchange with the central control center to realize
remote monitoring and control.

Fault diagnosis and troubleshooting steps

Step - Contact local LiuGong dealers and authorized service centers.

6-278
6.4 Fault Code December 30, 2017
6.4.89 DTC 261711 Automatic Locking Level 2 Abnormal GPS Heartbeat, and the Machine is Prohibited for

6.4.89 DTC 261711 Automatic Locking Level 2 Abnormal GPS Heartbeat,

and the Machine is Prohibited for Use

DTC Description Consequence

Automatic locking level 2 abnormal GPS heartbeat, and the
261711 The machine is prohibited for use.
machine is prohibited for use.

System description

Use the GPS (Global Positioning System) to position the machine and use the GSM mobile
communication network to achieve the two-way data exchange with the central control center to realize
remote monitoring and control.
 6-279
December 30, 2017 6.4 Fault Code
CLG930E/936E6.4.89 DTC 261711 Automatic Locking Level 2 Abnormal GPS Heartbeat, and the Machine is

Component location

GPS antenna

Display

GPS

Fault diagnosis and troubleshooting steps

Step 1 Check whether the GPS connector becomes loose and falls off.

Inspection method
Manually check the GPS connector for looseness or fall-off
Whether the GPS connector becomes loose and falls off?
YES NO
Tighten the GPS connector.
Go to Step 3 Go to Step 2

Step 2 Check the harness (No. 149) for fault.

Inspection method
Turn the start switch to the ON position.
Dismantle the GPS connector C3. Make sure no pin of the connector is bent. Turn the multimeter to its
voltage function, and measure the voltage between the connector terminal 4 and the grounding. The
voltage should be 24V. Otherwise, a fault develops in the harness (No. 149).
Whether the power cable has fault?
YES NO
Rewire.
Go to Step 3 Go to Step 3
6-280
6.4 Fault Code December 30, 2017
6.4.89 DTC 261711 Automatic Locking Level 2 Abnormal GPS Heartbeat, and the Machine is Prohibited for

Step 3 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check for fault.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
Maintenance is over steps or contact the local LiuGong dealers and
authorized service centers.
 6-281
December 30, 2017 6.4 Fault Code
CLG930E/936E6.4.90 DTC 261714 Forced Locking Level 2 Overdue Payment, and the Machine is Prohibited

6.4.90 DTC 261714 Forced Locking Level 2 Overdue Payment, and the
Machine is Prohibited for Use

DTC Description Consequence

Forced locking level 2 payment expired, and the machine
261714 The machine is limited for use.
is prohibited for use.

System description

Use the GPS (Global Positioning System) to position the machine and use the GSM mobile
communication network to achieve the two-way data exchange with the central control center to realize
remote monitoring and control.

Fault diagnosis and troubleshooting steps

Step - Contact local LiuGong dealers and authorized service centers.

6.4.91 DTC 261814 Please Pay the Due Loan on Time

DTC Description Consequence

The machine will be limited to be used if
261814 Please pay the due loan promptly.
overdue.

System description

Remind the owner of payment to avoid unnecessary faults.

Fault diagnosis and troubleshooting steps

Step – Pay the loan on time.

6-282
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.1 Troubleshooting Solution for E1-Battery Power Loss CLG930E/936E

6.5 Fault Diagnosis of Electrical System

6.5.1 Troubleshooting Solution for E1-Battery Power Loss

Fault SN Main reasons of faults Consequence

E1 Battery power loss The battery is damaged

System description

The battery functions: Store the electric energy; when the engine starts and powers the motor; for
gasoline engine, it can power the igniter; stabilize the system voltage; when the alternator does not
generate electricity or the voltage is low, the battery powers the electric equipment; when the alternator
is overloaded because of too many electric equipment, the battery assists the alternator to power; the
battery is equivalent to a big capacitor, it will protect the components and parts in case of transient
overvoltage.

Hydrometer

OK

Change

Replace

Component location
 6-283
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.1 Troubleshooting Solution for E1-Battery Power Loss

Fault diagnosis and troubleshooting steps

Step 1 The battery needs to be charged

Notice: Check the battery hydrometer color when the ignition switch is in OFF position.
Inspection method
1. Check the color of the battery hydrometer through the opening on the cover of the battery, black
means that the battery needs to be charged.
2. Measure the voltage on both ends of the battery with a multimeter: use DC voltage gear (200V) of
multimeter, connect the red probe to the positive terminal and the black probe to the negative
terminal. Under the normal condition, the voltage is 24V. If the voltage is too low, the battery needs
to be charged.
Whether the battery needs to be charged or not?
YES NO
Charge the battery
Go to Step 3 Go to Step 2

Step 2 The battery is aging and lack of power.

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
The machine does not work for a long time and the battery has not been charged so it is lack of power
seriously. Check it by referring to E2.
Is the battery aging and lack of power?
YES NO
Replace it with a new one.
Go to Step 3 Go to Step 3
Step 3 Check whether this fault is eliminated
Inspection method
After replacing a new battery, connect the battery firmly.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
steps or contact the local LiuGong dealers and
Maintenance is over authorized service centers.
Return
6-284
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.2 E2 Abnormal Battery CLG930E/936E

6.5.2 E2 Abnormal Battery

Fault SN Main reasons of faults Consequence

E2 The battery is abnormal The battery is damaged

System description

The battery functions: Store the electric energy; when the engine starts and powers the motor; for
gasoline engine, it can power the igniter; stabilize the system voltage; when the alternator does not
generate electricity or the voltage is low, the battery powers the electric equipment; when the alternator
is overloaded because of too many electric equipment, the battery assists the alternator to power; the
battery is equivalent to a big capacitor, it will protect the components and parts in case of transient
overvoltage.
Common maintenance: the electric quantity of the battery can be learned by the change of the
hydrometer color. Green – normal, black – requiring to be charged, white – the battery is scrap.

Hydrometer

OK

Change

Replace

Component location
 6-285
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.2 E2 Abnormal Battery

Fault diagnosis and troubleshooting steps

Step 1 Normal battery level

Notice: Check the battery hydrometer color when the ignition switch is in OFF position.
Inspection method
Check the color of battery hydrometer through the opening on the cover of the battery.
Is the color of battery hydrometer green?
YES NO
The battery level is normal.
Go to Step 4 Go to Step 2

Step 2 The battery needs to be charged

Notice: Check the battery hydrometer color when the ignition switch is in OFF position.
Inspection method
Check the color of battery hydrometer through the opening on the cover of the battery.
Is the color of battery hydrometer black?
YES NO
Charge the battery
Go to Step 4 Go to Step 3

Step 3 The battery is scrapped

Notice: Check the battery hydrometer color when the ignition switch is in OFF position.
Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Check the color of battery hydrometer through the opening on the cover of the battery.
Is the color of battery hydrometer white?
YES NO
Repair or replace battery
Go to Step 4 Go to Step 4
6-286
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.2 E2 Abnormal Battery CLG930E/936E

Step 4 Check whether this fault is eliminated

Inspection method
Check the color of battery hydrometer through the opening on the cover of the battery.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
steps or contact the local LiuGong dealers and
Maintenance is over authorized service centers.
Return
 6-287
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.3 E3 Automatic Slowdown Failed

6.5.3 E3 Automatic Slowdown System description

Failed When you are not operating the lever,
accelerator pedal, the engine speed will drop to
the preset idle speed so as to achieve the
Main reasons of
Fault SN Consequence purpose of reducing fuel consumption or noise.
faults
No matter the lever or acceleration pedal, either
Increased fuel or the control lever of attachment is operated, the
Automatic
E3 consumption and engine speed will restore to the corresponding
slowdown fails
noise
speed of the current accelerator knob.

Component location

Display
Handle pressure switch Accelerator knob

Pedal pressure switch

Pressure switch
of appurtenances
6-288
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.3 E3 Automatic Slowdown Failed CLG930E/936E

Fault diagnosis and troubleshooting steps

Step 1 Operate the automatic idle speed control key to cancel the automatic idle speed function.

Whether the automatic idle speed function is canceled or not?

YES NO
Operate the control key of automatic idle speed on
the display to enable the automatic idle speed
function.
Go to Step 4 Go to Step 2

Step 2 Select mode L

Inspection method
Check the display for automatic idle speed icon and no icon means the automatic idle speed function is
canceled.
Whether the automatic idle speed function is canceled or not?
YES NO
Operate the control key of automatic idle speed on
the display to enable the automatic idle speed
function.
Go to Step 4 Go to Step 3

Step 3 121305, 121405, 231012, 231014 alarm appears on the display

Inspection method
Turn the ignition switch to ON state, and then check the alarm on the display.
Whether 121305, 121405, 231012, 231014 alarm appears on the display or not?
YES NO
Overhaul the machine in accordance with the
corresponding fault diagnosis and troubleshooting
steps of the DTC.
Go to Step 4 Go to Step 4
 6-289
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.3 E3 Automatic Slowdown Failed

Step 4 Check whether this fault is eliminated

Inspection method
Operate the machine, and check whether each action is normal.
Has this fault been eliminated?
YES NO
Find out the engine system fault or contact the
local LiuGong dealers or authorized service
Maintenance is over centers.
Return
6-290
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.4 E4 Engine cannot be Started CLG930E/936E

6.5.4 E4 Engine cannot be Started

Fault SN Main reasons of faults Consequence

Engine cannot be started (the engine does not
E4 Fail to work.
rotate)

System description

In the condition where there is no fault on the machine and the excavator is started in the correct steps,
the pilot shut-off valve switch will be in normally closed state.
When the electric lock is turned to "On" position, the battery will power B1 end of the electric lock via
No.004 wire, 50A fuse, No.005, electric lock power supply 20A fuse and N0.110 wire. Connect B2 end of
the electric lock in the electric lock. B2 end controls the battery relay closed via No.145 wire, diode D6
and No.155 wire. B2 end powers the holding coil of the oil cut-off valve via No.146 and the coil
commander. In the meantime, B2 end powers 86 end of the starter relay K10 via No.144, the starter
relay K10 will be closed. The starter relay K10 will control pilot control relay K7 closed via end 81 of the
starter relay K10, No.300 wire, pilot shut-off valve switch and No.310 wire.
When the electric lock is turned to "Start" position, the end S gets connected to the power. The end S
powers the end 30 of the pilot control relay K7 via No.180 wire, and powers starter relay K1 and oil shut-
off valve relay K2 simultaneously via end 30 of the pilot control relay K7, end 87 of the pilot control relay
K7, No.525 wire, 87 A end of controller control starter relay K8 and No.181 wire; starter relay K1 and oil
shut-off valve relay K2 will be closed during the power supply. The battery powers push-pull coil of the oil
cut-off valve via battery relay, No.105 wire, 50A fuse, No.136 wire, No.138 wire, oil shut-off valve relay
K2, No.183 wire and the coil commander, promoting oil shut-off valve will be closed and connecting to
the diesel fuel supply passage of the engine. In the meantime, the battery controls starter Motor closed
via the battery relay, No.105 wire, 50A fuse, No.136, starter relay K1, No.182 and end 50 of the starter
Motor, the starter Motor will rotate. Drive the crankshaft of engine to rotate. Then engine is energized.
 6-291
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.4 E4 Engine cannot be Started
6-292
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.4 E4 Engine cannot be Started CLG930E/936E

K7 K8
 6-293
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.4 E4 Engine cannot be Started

Component location

Ignition switch IPC controller

Starting motor

Fuse box
Pilot cut-off
valve switch

Fault diagnosis and troubleshooting steps

Step 1 Immobilization alarm appears on the display

Inspection method
Turn the ignition switch to ON state, and then check the alarm on the display.
Do the alarm with DTCs of 261711, 261714 appear on the display?
YES NO
Overhaul the machine in accordance with the
corresponding fault diagnosis and troubleshooting
steps of the DTC.
Go to Step 15 Go to Step 2
6-294
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.4 E4 Engine cannot be Started CLG930E/936E

Step 2 Fuel level is too low

Inspection method
Check the fuel level.
Whether the fuel level is too low or not?
YES NO
Refuel.
Go to Step 15 Go to Step 3

Step 3 Battery voltage is too low.

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
1. Turn the start switch to ON state, and then check the display for the alarm with the fault code of
101001and 101017.
2. Measure the storage battery voltage with the multimeter: Turn the multimeter to its DC voltage
function (200V), and connect the red probe to the positive storage battery terminal and the black
probe to the negative storage battery terminal. See the schematic diagram for detection as follows:

Black probe
Red probe

Voltage value is 24V in the normal condition.

Whether the battery voltage is too low or not?
YES NO
Overhaul the machine in accordance with the
corresponding fault diagnosis and troubleshooting
steps of the fault code, or charge the battery or
replace the battery.
Go to Step 15 Go to Step 4
 6-295
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.4 E4 Engine cannot be Started

Step 4 Fuse blows

Notice: The start switch is in OFF state.

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
1. Open the electrical control unit, remove the fuse, visibly check whether the fuse blows or check
whether both ends of the fuse are connected by the multimeter on the diode gear.
2. Open the fuse box, unplug the fuses 1 and 14 by a fuse clip, and observe by visual inspection
whether the fuse is blown or measure by the DIO position of multimeter whether both ends of fuse
are connected.
Note: There may be grounding fault, so please refer to step 14.
Is the fuse blown?
YES NO
Replace the fuse
Go to Step 15 Go to Step 5

Step 5 Start switch fault,

Notice: remove the battery negative cable.

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Measure the resistance between the start switch B1 and S with multimeter.
1. When the start switch is turned to OFF state, the resistance between B1 and S is infinite.
2. When the start switch is turned to START state, the resistance between B1 and S is less than 10Ω.
Whether the ignition switch is faulty?
YES NO
Replace the ignition switch
Go to Step 15 Go to Step 6
6-296
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.4 E4 Engine cannot be Started CLG930E/936E

Step 6 Pilot solenoid valve cut-off switch fault

Notice: The start switch is in OFF state.

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Measure the resistance between the pilot solenoid valve cut-off switch S13 (male 1) and S13 (male 3)
with multimeter
1. When the switch of pilot solenoid valve is turned to Locked state, the resistance between S13 (male
1) and S13 (male 3) is less than 10Ω.
2. When the switch of pilot solenoid valve is turned to Unlocked state, the resistance between S13
(male 1) and S13 (male 3) is infinite.
Whether the cut-off switch of pilot solenoid valve fails?
YES NO
Repair or replace the cut-off switch of pilot
solenoid valve.
Go to Step 15 Go to Step 7

Step 7 Safety relay K10 fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Measure the resistance between each two contacts of safety relay K10 with a multimeter.
1. Remove the safety relay K10, and then measure the resistance among all contacts.
The resistance between 85 and 86 (coil resistance) is approx. 320-360Ω.
The resistance between 30 and 87 is infinite.
The resistance between 30 and 87a is less than 10Ω.
2. Switch on 24V power to both ends of 85 and 86, and measure the resistance between each two
contacts.
The resistance between 30 and 87 is less than 10Ω.
The resistance between 30 and 87a is infinite.
Whether safety relay K10 fails?
YES NO
Replace the safety relay.
Go to Step 15 Go to Step 8
 6-297
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.4 E4 Engine cannot be Started

Step 8 Pilot control starter relay K7 fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Measure the resistance among all contacts of pilot control starter relay K7 with a multimeter.
1. Remove pilot control start relay K7, and then measure the resistance among all contacts.
The resistance between 85 and 86 (coil resistance) is approx. 320-360Ω.
The resistance between 30 and 87 is infinite.
The resistance between 30 and 87a is less than 10Ω.
2. Switch on 24V power to both ends of 85 and 86, and measure the resistance between each two
contacts.
The resistance between 30 and 87 is less than 10Ω.
The resistance between 30 and 87a is infinite.
Whether the starter relay K7 controlled by the pilot fails or not?
YES NO
Replace the pilot control starter relay.
Go to Step 15 Go to Step 9

Step 9 starter relay K8 controlled by controller fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Measure the resistance among all contacts of starter relay K8 controlled by controller with a multimeter.
1. Remove start relay K8 controlled by controller, and then measure the resistance among all
contacts.
The resistance between 85 and 86 (coil resistance) is approx. 320-360Ω.
The resistance between 30 and 87 is infinite.
The resistance between 30 and 87a is less than 10Ω.
2. Switch on 24V power to both ends of 85 and 86, and measure the resistance between each two
contacts.
The resistance between 30 and 87 is less than 10Ω.
The resistance between 30 and 87a is infinite.
Whether starter relay K8 controlled by controller fails or not?
YES NO
Replace the starter relay controlled by a controller.
Go to Step 15 Go to Step 10
6-298
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.4 E4 Engine cannot be Started CLG930E/936E

Step 10 the auto preheating relay K2 for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Measure the resistance among all contacts of starter relay K1 with a multimeter.
1. Remove the start relay K1, and then measure the resistance among all contacts.
The resistance of coil is about79-81Ω.
The resistance of the main contact is infinite.
2. Supply 24V power to both ends of the coil and measure the resistance between two main contacts.
The resistance of the main contacts is less than 10Ω.
Oil cut-off valve relay K2 for fault?
YES NO
Replace oil cut-off valve relay.
Go to Step 15 Go to Step 11

Step 11 Starter relay K1 fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Measure the resistance among all contacts of starter relay K1 with a multimeter.
1. Remove the start relay K1, and then measure the resistance among all contacts.
The resistance of coil is about 80Ω.
The resistance of the main contact is infinite.
2. Supply 24V power to both ends of the coil and measure the resistance between two main contacts.
The resistance of the main contacts is less than 10Ω.
Whether starter relay K1 fails or not?
YES NO
Replace the starter relay.
Go to Step 15 Go to Step 12
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December 30, 2017 6.5 Fault Diagnosis of Electrical System
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Step 12 Fault of starter motor.

Notice: Remove the wiring on the input end 50 and end 30 on the starter motor.
Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
1. Turn the start switch to ON position, and then measure the voltage to earth of wire 108 on the end
50, and make sure it is 24V.
2. Turn the start switch to START position, and then measure the voltage between the harness (# 182)
at end 30 and the grounding, and the voltage is 24V.
If the input signals are normal, but the starter motor does not rotate, it can be judged that there is a fault
in the starter motor.
Whether the start motor has fault or not?
YES NO
Replace the starter motor.
Go to Step 15 Go to Step 13
6-300
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.4 E4 Engine cannot be Started CLG930E/936E

Step 13 Open circuit or poor contact of wire in harness or connector

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
Remove the battery cable (-), and turn the start switch to OFF position, measure the resistance of the
following circuit, and the resistance shall be less than 10Ω in normal condition.
1. Wire 105 on the main contact of battery relay - wire 136 of the main contact of starter relay K1.
2. Wire 182 on the main contact of start relay K1 - end 50 of starter motor.
3. Wire 004 on the main contact of battery relay - X2(8) - X1(5) - end B1 of start switch.
4. End S of start switch - X2(2) - end 30 of start relay K7 controlled by pilot.
5. Terminal 87 of start relay K7 controlled by pilot - start relay K8 (30-87A) - X1(19) - wire 181 on the
start relay K1 and wire 181 on the oil cut-off valve relay K2.
6. Wire 260 on the starter relay K1 - frame ground (GND)
7. Wire 102 on the main contact of battery relay -X2 (12) - end 30 of the safety relay K10
8. End 87 of safety relay K10- X1(21) -switch of pilot shut -off valve (3-1) - X2(3) -end 86 of starter
relay K7 controlled by pilot
9. Wire 85 on the start relay K7 controlled by pilot - frame ground (GND)
10. End B2 of start switch - X1(28) - end 86 of safety relay K10
11. Wire 85 on the safety relay K10 - frame ground (GND)
12. J2(female 23) - X2(15) - end 86 of the starter relay K8 controlled by controller
13. End 85 on the start relay K8 controlled by controller - frame ground (GND)
14. End S of ignition switch - J1 (female 10)
15. End B2 of start switch - End + of battery relay.
16. End - of battery relay - frame ground (GND).
Is the harness open-circuit?
YES NO
Connect the harness again and wrap the harness
Go to Step 15 Go to Step 14
 6-301
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.4 E4 Engine cannot be Started

Step 14 Wire in harness shorted to the grounding wire

Notice: Shutdown operation is needed

Inspection method
Remove the battery cable (-), and turn the start switch to OFF position, check whether the following
circuits are shorted to ground, and normally the resistance between any check point and the ground
shall be greater than 1MΩ.
1. Wire 105 on the main contact of battery relay - main contact of starter relay K1 - end 50 of the
starter motor
2. Wire 004 on the main contact of battery relay - X2(8) - X1(5)- start switch (B1-S) - X2(2) - relay K7,
K8, K9 (main contact) -X1(19)- wire 181 on the coil contact of starter relay K1
3. Wire 102 on the main contact of battery relay -X2 (12) - safety relay K11 (main contact) - X1(21) -
switch of pilot shut-off valve (3-1) - X2(3) - end 86 of starter relay K7 controlled by pilot
4. Ignition switch (B1-S)- J1 (female 10)
Is the harness short-circuit?
YES NO
Connect the harness again and wrap the harness
Go to Step 15 Go to Step 15

Step 15 Check whether this fault is eliminated

Inspection method
Operate the machine, and check whether each action is normal.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
steps or contact the local LiuGong dealers and
Maintenance is over authorized service centers.
Return
6-302
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.5 E5 Preheater does not Work CLG930E/936E

6.5.5 E5 Preheater does not Work

Fault SN Main reasons of faults Consequence

E5 Pre-heater fails to work The machine is difficult to start or fails to start.

System description

The preheating function is divided into manual preheating and automatic preheating. Manual preheating
means to turn the start switch from OFF position to HEAT position, preheating relay K3 is closed, and the
battery supplies power to the pre-heater of the engine. Automatic preheating means that the controller
can make judgment based on the external environment to determine whether it requires preheating or
not. When preheating is required in accordance with the judgment, the output of J2-11 on controller is
24V, which drives the automatic preheating relay K9 to be closed to make preheating relay K3
energized, so that the preheating relay K3 is closed and the battery supplies power to the pre-heater of
the engine. The figure below is the electrical circuit diagram of engine preheater.
 6-303
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.5 E5 Preheater does not Work
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6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.5 E5 Preheater does not Work CLG930E/936E

Component location

Preheater

Ignition switch

Fuse box
Engine controller

Fault diagnosis and troubleshooting steps

Step 1 Ignition switch fault

Notice: Remove the battery negative cable.

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Measure the resistance between the start switch B1 and G1 with multimeter.
1. When the start switch is turned to OFF state, the resistance between B1 and G1 is infinite.
2. When the start switch is turned to HEAT position, the resistance between B1 and G1 is less than
10Ω.
Is the start switch damaged?
YES NO
Replace the ignition switch
Go to Step 7 Go to Step 2
 6-305
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.5 E5 Preheater does not Work

Step 2 Preheating relay fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Measure the resistance between each two contacts of preheating relay K3 with a multimeter.
1. Remove the preheat relay K3, and then measure the resistance among all contacts.
The resistance of coil is about 61-63Ω.
The resistance of the main contact is infinite.
2. Supply 24V power to both ends of the coil and measure the resistance between two main contacts.
The resistance of the main contacts is less than 10Ω.
Is there a fault in the preheating relay?
YES NO
Replace the preheating relay.
Go to Step 7 Go to Step 3

Step 3 Fuse blows

Notice: The start switch is in OFF state.

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
1. Open the electrical control unit, remove the fuse, visibly check whether the fuse blows or check
whether both ends of the fuse are connected by the multimeter on the diode gear.
2. Open the fuse box, unplug the fuse 2 by a fuse clip, and observe by visual inspection whether the
fuse is blown or measure by the DIO position of multimeter whether both ends of fuse are
connected.
Note: There may be grounding fault, so please refer to step 5
Is the fuse blown?
YES NO
Replace the fuse
Go to Step 7 Go to Step 4
6-306
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.5 E5 Preheater does not Work CLG930E/936E

Step 4 Open circuit or poor contact of wire in harness or connector

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
Remove the battery cable (-), and turn the start switch to OFF position, measure the resistance of the
following circuit, and the resistance shall be less than 10Ω in normal condition.
1. Wire 105 on the main contact of battery relay - wire 104 of the main contact of preheating relay K3.
2. Wire 185 on the main contact of preheat relay K3 - terminal of the pre-heater.
3. End G1 of start switch - wire 190 on the coil of preheat relay K3.
4. Wire 260 on the preheat relay K3 - frame ground (GND).
5. End 87 of automatic preheating relay K9 X1(20) - wire 190 on the coil of preheating relay K3.
6. Wire 102 on the main contact of battery relay - X2(12) - end 30 of the automatic preheating relay K9
7. End 86 of automatic preheating relay K9 - J2(11).
8. End 85 of the automatic preheating relay K9 - frame ground (GND).
Is the harness open-circuit?
YES NO
Connect the harness again and wrap the harness
Go to Step 7 Go to Step 5

Step 5 Wire in harness shorted to the grounding wire

Notice: Shutdown operation is needed

Inspection method
Remove the battery cable (-), and turn the start switch to OFF position, check whether the following
circuits are shorted to ground, and normally the resistance between any check point and the ground
shall be greater than 1MΩ.
1. Wire 105 on the main contact of battery relay - main contact of preheating relay K3 - terminal of pre-
heater.
2. End G1 of start switch - wire 190 on the coil of preheat relay K3
3. Wire 102 on the main contact of battery relay - X2(12) - automatic preheating relay K9 (main
contact) - X1(20)- wire190 on the coil of preheating relay K3
Is the harness short-circuit?
YES NO
Connect the harness again and wrap the harness
Go to Step 7 Go to Step 6
 6-307
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.5 E5 Preheater does not Work

Step 6 Pre-heater fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to HEAT position, when the voltage measured between the terminal of pre-heater
and the ground is 24V, if the pre-heater still does not work, it can be determined as the internal fault of
the pre-heater.
Is there a fault in the pre-heater?
YES NO
Replace the preheater.
Go to Step 7 Go to Step 7

Step 7 Check whether this fault is eliminated

Inspection method
Operate the machine, and check whether each action is normal.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
steps or contact the local LiuGong dealers and
Maintenance is over authorized service centers.
Return
6-308
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.6 E8 All the Work Implements, Revolving and Traveling cannot Move CLG930E/936E

6.5.6 E8 All the Work Implements, Revolving and Traveling cannot Move

Fault SN Main reasons of faults Consequence

All the work implements, revolving system and
E6 No action and fails to work.
travel system fail to move

System description

Power on, pull up the shut-off switch of pilot solenoid valve to connect wire 300 and 481, at this time, the
electrical circuit of the pilot shut-off solenoid valve is connected, and the oil path of the pilot shut-off
solenoid valve is open, so the hydraulic system starts running. The following is the electrical circuit
diagram of the pilot shut-off.
 6-309
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.6 E8 All the Work Implements, Revolving and Traveling cannot Move

Component location

Ignition switch

Fuse box
Pilot cut-off valve switch

Fault diagnosis and troubleshooting steps

Step 1 Check whether the fuse 1 is blown

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Unplug the fuse 1 by a fuse clip, visually check whether the fuse is blown or check whether both ends
of the fuse are connected by the multimeter on the diode gear.
Note: There may be grounding fault, so please refer to step 5.
Is fuse 1 blown?
YES NO
Replace the fuse
Go to Step 6 Go to Step 2

Step 2 Pilot solenoid valve shut-off switch fault (switch closed).

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
While pulling up the shutoff switch of pilot solenoid valve, the pin 2 and pin 3 on the shutoff switch of
pilot solenoid valve are connected, and at this time measure the shutoff switch with a multimeter on the
diode position.
Is the switch closed?
YES NO
Repair or replace the shut-off switch of the pilot
solenoid valve.
Go to Step 6 Go to Step 3
6-310
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.6 E8 All the Work Implements, Revolving and Traveling cannot Move CLG930E/936E

Step 3 Check whether the safety relay fails.

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Measure the resistance between each two contacts of safety relay K10 with a multimeter.
1. Remove the safety relay K10, and then measure the resistance among all contacts.
The resistance between 85 and 86 (coil resistance) is approx. 320-360Ω.
The resistance between 30 and 87 is infinite.
The resistance between 30 and 87a is less than 10Ω.
2. Switch on 24V power to both ends of 85 and 86, and measure the resistance between each two
contacts.
The resistance between 30 and 87 is less than 10Ω.
The resistance between 30 and 87a is infinite.
Is there a fault in the safety relay?
YES NO
Repair or replace safe relay.
Go to Step 6 Go to Step 4

Step 4 Open circuit or poor contact of wire in harness or connector

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
Remove the battery cable (-), and turn the start switch to OFF position, measure the resistance of the
following circuit, and the resistance shall be less than 10Ω in normal condition.
1. Wire 102 on the main contact of battery relay -X2 (12) - end 30 of the safety relay K10
2. End 87 of safety relay K10 - X1(21) - S13 (female 3) of pilot shutoff valve switch
3. S13 (female 2) of pilot shutoff valve switch - pilot shutoff solenoid valve A1 (female 1)
4. Pilot shutoff solenoid valve A1 (female 1)- frame ground (GND)
5. End B2 of start switch - X1(28) - end 86 of safety relay K10
6. Terminal 85 on the safety relay K10 -X2 (16) - frame ground (GND)
Is the harness open-circuit?
YES NO
 6-311
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.6 E8 All the Work Implements, Revolving and Traveling cannot Move

Connect the harness again and wrap the harness

Go to Step 6 Go to Step 5
6-312
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.6 E8 All the Work Implements, Revolving and Traveling cannot Move CLG930E/936E

Step 5 Wire in harness is fault -- shorted to ground wire.

Notice: Shutdown operation is needed

Inspection method
Remove the battery cable (-), and turn the start switch to OFF position, check whether the following
circuits are shorted to ground, and normally the resistance between any check point and the ground
shall be greater than 1MΩ.
1. Wire 102 on the main contact of battery relay -X2 (12) - end 30 of the safety relay K10
2. End 87 of safety relay K10 - X1(21) - pilot shut off valve switch (3-2) - pilot shut off solenoid valve A1
(female 1)
3. End B2 of ignition switch - X1(28) - end 86 of safety relay K10
Is the harness short-circuit?
YES NO
Connect the harness again and wrap the harness
Go to Step 6 Go to Step 6

Step 6 Check whether this fault is eliminated

Inspection method
Operate the machine, and check whether each action is normal.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
steps or contact the local LiuGong dealers and
Maintenance is over authorized service centers.
Return
 6-313
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.7 E9 Display Panel Showing Nothing

6.5.7 E9 Display Panel Showing System description

Nothing Protect the constant power end by fuse 15,
control the energy power in the display by start
switch, and if the power circuit is normal, turn on
Fault Main reasons
Consequence the display.
SN of faults
Display panel It can not display the
E7
shows nothing machine information
6-314
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.7 E9 Display Panel Showing Nothing CLG930E/936E

Component location

Display Ignition switch

Fuse box

Fault diagnosis and troubleshooting steps

Step 1 Blowing of fuse -15

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Unplug the fuse 15 by a fuse clip, visually check whether the fuse is blown or check whether both ends
of the fuse are connected by the multimeter on the diode gear.
Note: There may be grounding fault, so please refer to step 3.
Is fuse 15 blown?
YES NO
Replace the fuse.
Go to Step 2
Go to Step 5
 6-315
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.7 E9 Display Panel Showing Nothing

Step 2 Open circuit or poor contact of wire in harness or connector

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
Remove the battery cable (-), and turn the start switch to OFF position, measure the resistance of the
following circuit, and the resistance shall be less than 10Ω in normal condition.
7. Wire 004 on the main contact of battery relay -X2(8)-X1(1)-X3(6)- C4(female 6) of the display
8. X1 (female1)- X4 (7)- display C4 (femal7)
9. C4 (female 5) of the display-X4(5) - frame ground (GND)
10. C4 (female 10)-X3(10) of the display - frame ground (GND)
11. Terminal S of start switch - X3 (8) - C4 (female 26) of the display
Is the harness open-circuit?
YES NO
Connect the harness again and wrap the harness
Go to Step 5 Go to Step 3

Step 3 Wire in harness grounding fault --- shorted to ground wire

Notice: Shutdown operation is needed

Inspection method
Remove the battery cable (-), and turn the start switch to OFF position, check whether the following
circuits are shorted to ground, and normally the resistance between any check point and the ground
shall be greater than 1MΩ.
1. Wire 004 on the main contact of battery relay -X2(8)-X1(1)-X3(6)- C4(female 6) of the display
2. X1 (female1)- X4 (7)- display C4 (femal7)
3. Terminal S of start switch - X3 (8) - C4 (female 26) of the display
Is the harness short-circuit?
YES NO
Connect the harness again and wrap the harness
Go to Step 5 Go to Step 4
6-316
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.7 E9 Display Panel Showing Nothing CLG930E/936E

Step 4 Display fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to ON position, check the power supply with the multimeter, when all the following
conditions are satisfied, if the display is still off, it can be determined as internal fault of the display.
1. The voltage to ground of the display C4 (6) is 24V
2. The voltage to ground of the display C4 (7) is 24V
3. The voltage to ground of the display C4 (26) is 24V
4. The voltage to ground of the display C4 (5) is 0V
5. The voltage to ground of the display C4 (10) is 0V
Whether the display is faulty?
YES NO
Replace the display.
Go to Step 5 Go to Step 5

Step 5 Check whether this fault is eliminated

Inspection method
Operate the machine, and check whether each action is normal.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
steps or contact the local LiuGong dealers and
Maintenance is over authorized service centers.
Return
 6-317
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.8 E8- Incorrectly Displayed Hydraulic Oil Temperature

6.5.8 E8- Incorrectly Displayed System description

Hydraulic Oil Temperature The hydraulic oil temp sensor monitors the actual
temperature, and outputs different resistances to
the engine controller; the engine controller sends
Main
the hydraulic oil temperature to the display
Fault SN reasons of Consequence
through CAN bus, so the hydraulic oil
faults
temperature can be displayed on the display.
Reducing the pump
current and engine
Incorrect speed can affect the
display of working performance of
E8
hydraulic oil the complete machine,
temperature or cause damage to the
engine and hydraulic
components

Hydraulic oil temperature sensor parameter

table

Coolant temperature
(Celsius degree )
Resistance (Ohm)

Component location

Front

Hydraulic oil
temperature
sensor
6-318
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.8 E8- Incorrectly Displayed Hydraulic Oil Temperature CLG930E/936E

Fault diagnosis and troubleshooting steps

Step 1 Hydraulic oil temperature sensor fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the knob start switch to OFF position and disconnect sensor connector:
1. Check the connector for looseness, rust, bending and damage.
2. Turn the multimeter to its resistance function (20kΩ), and measure the resistance between the
sensor connector terminals 1 and 2, comparing the result with the parameter table (normally, <4kΩ).
Whether the hydraulic oil temp sensor fails?
YES NO
Replace the hydraulic oil temp sensor.
Go to Step 4 Go to Step 2

Step 2 Open circuit or poor contact of wire in harness or connector

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
Remove the battery cable (-), and turn the start switch to OFF position, measure the resistance of the
following circuit, and the resistance shall be less than 10Ω in normal condition.
1. J1 (31) of the controller - P7 (1) of hydraulic oil temp sensor
2. J2 (22) of engine controller - P7 (2) of hydraulic oil temp sensor
Is the harness open-circuit?
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
 6-319
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.8 E8- Incorrectly Displayed Hydraulic Oil Temperature

Step 3 Wire in harness grounding fault --- shorted to ground wire

Notice: Shutdown operation is needed

Inspection method
Remove the battery cable (-), and turn the start switch to OFF position, check whether the following
circuits are shorted to ground, and normally the resistance between any check point and the ground shall
be greater than 1MΩ.
J1 (31) of the controller - P7 (1) of hydraulic oil temp sensor
Is the harness open-circuit?
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 4
Step 4 Check whether this fault is eliminated

Inspection method
Operate the machine, and check whether each action is normal.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
steps or contact the local LiuGong dealers and
Maintenance is over authorized service centers.
Return
6-320
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.9 E11 Fuel Gauge cannot Display correctly CLG930E/936E

6.5.9 E11 Fuel Gauge cannot

System description
Display correctly
The fuel level sensor is a reed pipe type. The
magnetic floater density is lower than the
Main working medium (diesel) density, so the fuel level
Fault SN reasons of Consequence sensor floats on the surface of the working
faults medium and can slide up and down on the reed
Fuel gauge The fuel level display is pipe. When the floater moves on the reed pipe,
E11 cannot display inaccurate, which brings the on-off of the internal circuit of the reed pipe is
correctly trouble to the work. controlled by a magnetic field to allow the
resistance between the two output leads of the
connector to change. Therefore, the fuel level
change is converted into a resistance signal
output, and through connecting to the controller
the fuel level in the tank is detected, and through
connecting to the display instrument the fuel
level is displayed.

LG922E930E06032

Fuel level sensor parameter table

Floater position Floater position

Output resistance Output resistance
(Refer to the place at (Refer to the place at
(Ω) (Ω)
17.5mm) 17.5mm)
Below L1 1100±11.0 L11-L12 550±5.5
L1-L2 1050±10.5 L12-L13 500±5.0
L2-L3 1000±10.0 L13-L14 450±4.5
L3-L4 950±9.5 L14-L15 400±4.0
L4-L5 900±9.0 L15-L16 350±3.5
L5-L6 850±8.5 L16-L17 300±3.0
L6-L7 800±8.0 L17-L18 250±2.5
L7-L8 750±7.5 L18-L19 200±2.0
L8-L9 700±7.0 L19-L20 150±1.5
L9-L10 650±6.5 L20-L21 100±1.0
L10-L11 600±6.0
 6-321
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.9 E11 Fuel Gauge cannot Display correctly

Oil level

Component location

Front

Fuel level sensor

6-322
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.9 E11 Fuel Gauge cannot Display correctly CLG930E/936E

Fault diagnosis and troubleshooting steps

Step 1 Check the fuel level sensor for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Notice: High temperature and high pressure oil or water can cause personal injury! When
replacing the sensor, please shut down the engine first and wait until the engine and gearbox
housing are sufficiently cooled.
Notice: When installing the fuel level sensor into the fuel tank, wipe off the water and keep
it clean.
Inspection method
Turn the start switch to the OFF position, and disconnect the connector from the fuel level sensor:
1. Check the connector for looseness, rust, bending and damage.
2. Turn the multimeter to its resistance function, and measure the resistance between the fuel level
sensor connector terminals 1 and 2 (normally, <2kΩ, for the specific resistance, see the figure.).

Whether the fuel level sensor fails?

YES NO
Repair or replace the fuel level sensor.
Go to Step 4 Go to Step 2
 6-323
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.9 E11 Fuel Gauge cannot Display correctly

Step 2 Check the harness for open-circuit

Notice: Correctly tie up harness and wire:

Avoid folding or bending the harness forcibly. It shall be kept away from moving components as
far as possible to prevent tensile failure and wear. Avoid friction with sharp metal edges. Keep
away from oil and water as far as possible. Keep away from high temperature parts (e.g. engine
block) as far as possible.
Inspection method
1. Check the harness (# 930) and the grounding wire between the controller (J2-30) and fuel level
sensor for wear.
2. Disconnect the fuel level sensor connector and the controller connector. Check the harness for
open-circuit:
(1) Turn the multimeter to its resistance function, and measure the resistance between the grounding
wire sensor terminal and the grounding (normally, <10Ω).

Gray wire

(2) Turn the multimeter to its resistance function, and measure the resistance between the connector
terminals J2-30 and sensor harness (normally, <10Ω).

White wire

To the black probe

To the red probe

6-324
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.9 E11 Fuel Gauge cannot Display correctly CLG930E/936E

Is the harness open-circuit?

YES NO
Connect the harness again and wrap the harness.
Go to Step 4 Go to Step 3
Step 3 Check the connector for fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Connect the fuel-level sensor connector and disconnect the controller connector. Turn the multimeter to
its resistance function, and measure the resistance between the harness at the controller port J2-30
and the grounding (normally, 2 kΩ, for the specific resistance, see the attached drawing).

White wire

To the black probe

To the red probe

When the resistance is abnormal, this indicates the connector is poorly contacted.
Whether the connector is faulty?
YES NO
Replace the connector.
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Turn the start switch to the ON position and re-check the DTC.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
steps or contact the local LiuGong dealers and
Maintenance is over authorized service centers.
Return
 6-325
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.10 E10 Windshield Wiper out of Work

6.5.10 E10 Windshield Wiper out System description

of Work The following diagram is the electrical circuit
diagram of the wiper system: when the switch is
in position 0, M4(1) and M4(3) are connected,
Main
wiper motor stops and resets to the original
Fault SN reasons of Consequence
position; when the switch is in position 1, M4(3)
faults
and the power are connected, and the wiper
Windshield Foreign matters on glass motor operates in the low speed state; when the
E10 wiper does not cannot be removed; the switch is turned to position 2, M4(2) and the
work sight for operator is poor.
power are connected, and the wiper motor
operates in the fast speed state.
6-326
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.10 E10 Windshield Wiper out of Work CLG930E/936E

Component location

Wiper switch

Wiper motor

Fuse box

Fault diagnosis and troubleshooting steps

Step 1 Check whether the fuse 9 is blown

Notice: Shutdown operation is needed

Inspection method
Unplug the fuse 9 by a fuse clip, visually check whether the fuse is blown or check whether both ends
of the fuse are connected by the multimeter on the diode gear.
Note: There may be grounding fault, so please refer to step 4.
Is fuse 9 blown?
YES NO
Replace the fuse
Go to Step 2
Go to Step 6
 6-327
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.10 E10 Windshield Wiper out of Work

Step 2 Wiper switch fault

Notice: When replacing the components, please be sure to use LiuGong parts.

Inspection method
Disconnect connector S1, check the connection condition of pins with the multimeter when the wiper
switch is turned to different positions, when there is no fault in the wiper switch, the connection
condition of pins are shown as follows:
1. When the wiper switch is in the 0 position, the resistance between pin 5 and pin 7 of S1 is less than
10Ω, the resistance between pin 1 and pin 3 is infinite, and the resistance between pin 5 and pin 3
is infinite.
2. When the wiper switch is in the 1 position, the resistance between pin 5 and pin 3 of S1 is less than
10Ω, the resistance between pin 1 and pin 3 is infinite, and the resistance between pin 7 and pin 3
is infinite.
3. When the wiper switch is in the 2 position, the resistance between pin 1 and pin 3 of S1 is less than
10Ω, the resistance between pin 5 and pin 3 is infinite, and the resistance between pin 7 and pin 3
is infinite.
Is the wiper switch damaged?
YES NO
Replace the wiper switch
Go to Step 6 Go to Step 3
6-328
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.10 E10 Windshield Wiper out of Work CLG930E/936E

Step 3 Open circuit or poor contact of wire in harness or connector

Notice: Properly pack up the harness and leads: prevent the harness from being folded and
bent forcedly. It shall be kept away from moving components as far as possible to prevent
tensile failure and wear. Avoid friction with sharp metal edges. Keep away from oil and water as
far as possible. Keep away from high temperature parts (e.g. engine block) as far as possible.
Inspection method
Remove the battery cable (-), and turn the start switch to OFF position, measure the resistance of the
following circuit, and the resistance shall be less than 10Ω in normal condition.
1. Wiper switch S1 (female 1) - X3 (female3)- wiper motor M4 (female 2)
2. Wiper switch S1 (female 5) - X3 (2) -wiper motor M4 (female 3)
3. Wiper switch S1 (female 7) - X3 (1) -wiper motor M4 (female 1)
4. Wire 102 on the main contact of battery relay - X2(14) - main contact and end 86 of wiper relay K6 -
X1(24) - wiper switch S1 (female 3) -X3(4)- wiper motor M4 (female 6)
5. End 85 on the wiper relay K6 - X2(4) - X5(1) - door control wiper switch- X5(2) - frame ground
(GND)
Is the harness open-circuit?
YES NO
Connect the harness again and wrap the harness
Go to Step 6 Go to Step 4

Step 4 Wire in harness is fault -- shorted to ground wire.

Notice: Shutdown operation is needed

Inspection method
Remove the battery cable (-), and turn the start switch to OFF position, check whether the following
circuits are shorted to ground, and normally the resistance between any check point and the ground
shall be greater than 1MΩ.
1. Wiper switch S1 (female 1) - X3 (3) -wiper motor M4 (female 2)
2. Wiper switch S1 (female 5) - X3 (2) -wiper motor M4 (female 3)
3. Wiper switch S1 (female 7) - X3 (1) -wiper motor M4 (female 1)
4. Wire 102 on the main contact of battery relay - X2(14) - main contact and end 86 of wiper relay K6 -
X1(24) - wiper switch S1 (female 3) -X3(4)- wiper motor M4 (female 6)
Is the harness short-circuit?
YES NO
Connect the harness again and wrap the harness
Go to Step 6 Go to Step 5
 6-329
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.10 E10 Windshield Wiper out of Work

Step 5 Wiper motor fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Turn the start switch to ON position, check the power supply of the wiper motor with the multimeter;
when all the following conditions are satisfied, if the wiper motor is still off, it can be determined as
internal fault of the wiper motor.
1. When the wiper switch is in position 0, the voltage to ground of M4 (female 6) is 24V, and the
voltage to ground of M4 (female 4) is 0V.
2. When the wiper switch is in position 1, the voltage to ground of M4 (female 3) is 24V.
3. When the wiper switch is in position 2, the voltage to ground of M4 (female 2) is 24V.
Is the wiper motor damaged?
YES NO
Replace the wiper switch
Go to Step 6 Go to Step 6

Step 6 Check whether this fault is eliminated

Inspection method
Operate the wiper system and check whether each action is normal.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
steps or contact the local LiuGong dealers and
Maintenance is over authorized service centers.
Return
6-330
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.11 E13 Backup Alarm unable to Sound CLG930E/936E

6.5.11 E13 Backup Alarm unable System description

to Sound The figure below is the travel alarm electrical
circuit diagram. Operators can cancel or enable
the travel alarm function by operating buttons on
Fault Main reasons of
Consequence the display. The main controller judges whether
SN faults
the complete machine is on travel status in
Alarm system is accordance with the foot controlled oil circuit
Backup alarm does not faulty, causing pressure switch. If it is in travel status, J1-1 foot
E11
sound potential safety
of the main controller outputs 24V voltage to the
hazard.
travel alarm. If not, J1-1 foot of the main
controller outputs 0 V voltage to the travel alarm.
 6-331
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.11 E13 Backup Alarm unable to Sound

Component location

Front

Traveling alarm

Fault diagnosis and troubleshooting steps

Step 1 Open circuit or poor contact of wire in harness or connector

Notice: properly pack up the harness and leads: prevent the harness from being folded and
bent forcedly. It shall be kept away from moving components as far as possible to prevent
tensile failure and wear. Avoid friction with sharp metal edges. Keep away from oil and water as
far as possible. Keep away from high temperature parts (e.g. engine block) as far as possible.
Inspection method
Remove the battery cable (-), and turn the start switch to OFF position, measure the resistance of the
following circuit, and the resistance shall be less than 10Ω in normal condition.
1. Main controller J1 (female 1) – travel alarm N3 (female 1)
2. Travel alarm N3 (female 2) – frame ground
3. Main controller J2 (female 13) – foot controlled oil circuit pressure switch P10 (female 1)
4. Foot controlled oil circuit pressure switch P10 (female 2) - frame GND
Is the harness open-circuit?
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 2
6-332
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.11 E13 Backup Alarm unable to Sound CLG930E/936E

Step 2 Wire in harness is fault -- shorted to ground wire.

Notice: Shutdown operation is needed

Inspection method
Remove the battery cable (-), and turn the start switch to OFF position, check whether the following
circuits are shorted to ground, and normally the resistance between any check point and the ground
shall be greater than 1MΩ.
1. Main controller J1 (female 1) – travel alarm N3 (female 1)
2. Main controller J2 (female 13) – foot controlled oil circuit pressure switch P10 (female 1)
Is the harness short-circuit?
YES NO
Connect the harness again and wrap the harness
Go to Step 4 Go to Step 3
Step 3 Travel alarm fault

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Start the complete machine but do not pull up the pilot shut-off valve switch, unplug connector P10 of
the foot controlled oil circuit pressure switch, and measure the voltage value of N3 (female 1) over the
ground with a multimeter. The voltage is 24 V under normal conditions.
Whether the travel alarm is damaged?
YES NO
Replace the travel alarm
Go to Step 4 Go to Step 4

Step 4 Check whether this fault is eliminated

Inspection method
Operate the wiper system and check whether each action is normal.
Has this fault been eliminated?
YES NO
Troubleshoot again the faults according to the
steps or contact the local LiuGong dealers and
Maintenance is over authorized service centers.
Return
 6-333
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.12 E14 A/C Panel unable to Display

6.5.12 E14 A/C Panel unable to Display

Fault SN Main reasons of faults Consequence

E12 A/C panel displays nothing Air conditioning system cannot work

System description

1. Electrical schematic diagram of air conditioning system, see the figure.

2. The evaporator assembly arrangement schematic diagram
Front view

Air-mixing servo motor

Vent

Vent servo
motor

Foot vent

Water tempera-
ture sensor

Warm water Warm water

outlet inlet
6-334
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.12 E14 A/C Panel unable to Display CLG930E/936E

Bottom view

Internal air
sensor
Expansion valve
inlet

Internal-to-external
air switching motor

Fan speed control

resistance

Expansion valve
outlet
 6-335
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.12 E14 A/C Panel unable to Display

Rear view

Frost-prevention
probe
Switch

Fan motor

LG922E930E06130
6-336
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.12 E14 A/C Panel unable to Display CLG930E/936E

Fault diagnosis and troubleshooting steps:

Step 1: Base machine power fault;

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Check whether the voltage of the base machine harness (# 128) with mutually plugged A/C harness in
the cab is 24V with a multimeter.
Check the wire # 128 having 24V voltage?
YES NO
Find out the reason according to Step 2. Check whether A/C 30A fuse is damaged.
Go to Step 2 Go to Step 3

Step 2: Wire grounding fault - failed to connect with the ground wire;

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Check whether the base machine harness (# 210) with mutually plugged A/C harness in the cab is
grounded well with a multimeter.
Is there an open circuit in the grounding wire?
YES NO
Troubleshoot the grounding circuit of base
Find out the reason according to Step 3
machine harness.
Go to Step 4
Go to Step 6

Step 3: A/C 30A fuse is blown;

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Check A/C 30A fuse, visibly check whether the fuse is blown or check whether both ends of the fuse
are connected by the multimeter on the diode gear.
Is A/C 30A fuse blown?
YES NO
Replace A/C 30A fuse. Find out the reason according to Step 4.
Go to Step 6 Go to Step 4
 6-337
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.12 E14 A/C Panel unable to Display

Step 4 5A fuse of the A/C panel is damaged.

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Check 5A fuse of the evaporator as wire harness in the cab. Visibly check whether the fuse blows or
check whether both ends of the fuse are connected by the multimeter on the diode gear.
Whether the A/C panel fuse is faulty?
YES NO
Replace fuse of the A/C panel
Go to Step 6 Go to Step 5

Step 5: A/C panel fault (internal fault);

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Press the blowing rate switch, the air volume should be displayed in the A/C panel, and turn on the
LCD; after pressing other keys, indicators come on or corresponding icons are displayed on the LCD.
Whether the A/C panel is faulty?
YES NO
Replace the A/C panel
Go to Step 6 Go to Step 6

Step 6: Check whether this fault is eliminated;

Inspection method
Operate the machine, and check whether each action is normal.
Has this fault been eliminated?
YES NO
Look for the electrical system fault or contact local
Maintenance is over
LiuGong dealers and authorized service centers.
6-338
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.13 E13 A/C no Wind or Abnormal Air Volume CLG930E/936E

6.5.13 E13 A/C no Wind or Abnormal Air Volume

Fault SN Main reasons of faults Consequence

E13 A/C blows no air or air volume is abnormal The service effect of A/C is poor

Fault diagnosis and troubleshooting steps

Step 1: Blower main relay fault (internal fault);

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Measure the resistance between each two contacts of blower main relay with a multimeter, and judge
whether relay is damaged according to the resistance value provided in the following table.

Code for both

Relay ends of wire Standard value
(contact)
Unplug the relay Measure coil
240 ± 10 Ω
and measure the resistance
resistance among
all contacts E-3 contact Infinite

Whether the blower main relay is damaged?

YES NO
Replace the blower main relay.
Go to Step 6 Go to Step 2

Step 2: Power transistor fault.

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Press the air regulation switch on the A/C panel, and feel whether outlet airflow is changed with
adjustment of the blowing rate switch.
Whether outlet airflow is changed with adjustment of the blowing rate switch?
YES NO
Replace the power transistor
Go to Step 3 Go to Step 6
 6-339
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.13 E13 A/C no Wind or Abnormal Air Volume

Step 3: Blower motor fault (internal fault);

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Unplug the blower motor plug at the back of the evaporator assembly, and check whether there is short
circuit or open circuit of blower coil winding with a multimeter.
Whether the blower is faulty?
YES NO
Replace the blower. Find out the reason according to Step 4
Go to Step 6 Go to Step 4

Step 4: A/C wiring fault.

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Check whether connectors of A/C harness are connected stably, and whether there is open circuit or
short circuit caused by damage of wires.
Whether A/C wiring is abnormal?
YES NO
Check circuit fault points and repair them.
Go to Step 6 Go to Step 5

Step 5: Fault of A/C panel;

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
If the A/C panel is checked to be normal through step 1 to step 4, it may have been damaged.
Whether the A/C panel is faulty?
YES NO
Replace the A/C panel.
Go to Step 6 Go to Step 6

Step 6: Check whether this fault is eliminated.

Inspection method
Operate the machine, and check whether each action is normal.
Has this fault been eliminated?
YES NO
Look for the fault of air conditioning system or
Maintenance is over contact local LiuGong dealers and authorized
service centers.
6-340
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.14 E16 Poor A/C Refrigeration CLG930E/936E

6.5.14 E16 Poor A/C Refrigeration

Fault SN Main reasons of faults Consequence

Poor refrigerating effect of air conditioning
E14 Poor A/C refrigeration
system

Fault diagnosis and troubleshooting steps

Step 1: Compressor relay fault;

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Check whether the electromagnetic coil of the compressor clutch relay is open with a multimeter.
Whether the compressor clutch relay is faulty?
YES NO
Replace the compressor clutch relay
Go to Step 8 Go to Step 2

Step 2 Internal air sensor fault.

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
The internal sensor may fail and diagnose the fault of internal sensor
Whether the internal air sensor fails?
YES NO
Replace the internal air sensor.
Go to Step 3
Go to Step 8
 6-341
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.14 E16 Poor A/C Refrigeration

Step 3: High-low voltage protection switch fault;

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Unplug the pressure protection switch wiring harness on the high-pressure side connector of the
expansion valve, and use a multimeter to check whether both ends of the pressure switch is connected.
When the system pressure is larger than 0.196 MPa and less than 3.14 MPa, the pressure switch shall
be connected.
Is the high/ low pressure protective switch not damaged?
YES NO
Replace the high and low voltage protection
switch.
Go to Step 8 Go to Step 4

Step 4: Compressor clutch fault;

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Unplug the compressor clutch plug, and use a multimeter to check whether the compressor clutch coil
is open. Whether the compressor grounding wire is in good condition?
Whether there is a fault in the compressor clutch?
YES NO
Replace the A/C compressor.
Go to Step 8 Go to Step 5

Step 5: Compressor fault;

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Remove the A/C belt, and rotate the A/C compressor pulley by hand to check whether clamping
stagnation and abnormal noise happens on the compressor A/C pulley.
Whether the compressor is faulty?
YES NO
Replace the A/C compressor.
Go to Step 8 Go to Step 6
6-342
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.14 E16 Poor A/C Refrigeration CLG930E/936E

Step 6: Fault of A/C lines;

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Check whether connectors of A/C harness are connected stably, and whether there is open circuit or
short circuit caused by damage of wires.
Is there a fault in the A/C wiring?
YES NO
Check circuit faults and repair them
Go to Step 8 Go to Step 7

Step 7: Fault of A/C panel;

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
If the A/C panel is checked to be normal through step 1 to step 7, it may have been damaged.
Whether the A/C panel is faulty?
YES NO
Replace the A/C panel.
Go to Step 8 Go to Step 8

Step 8: Check whether this fault is eliminated;

Inspection method
Operate the machine, and check whether each action is normal.
Has this fault been eliminated?
YES NO
Look for the cooling system fault or contact local
Maintenance is over
LiuGong dealers and authorized service centers.
 6-343
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.15 E15 Air Conditioning Abnormal Alarm E11--Inner Gas Sensor Break Line

6.5.15 E15 Air Conditioning Abnormal Alarm E11--Inner Gas Sensor

Break Line

Fault SN Main reasons of faults Consequence

Abnormal A/C alarm E11 -- Internal air sensor
E15 The service effect of A/C is poor
open circuit

Fault diagnosis and troubleshooting steps

Step 1: Internal air sensor fault.

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
1. Press OFF on the A/C panel, the LCD does not display, and the A/C stops running;
2. Press the increase and decrease keys of the temperature setting switch in the meantime for over 3
seconds, the LCD will display DTCs;
3. If E11 fault code occurs, check whether the circuit of the inner gas sensor located in the return air
valve is open with a multimeter.
Whether the circuit of the internal air sensor is open circuit?
YES NO
Replace the internal air sensor.
Go to Step 4 Go to Step 2

Step 2 Internal air sensor is open circuit.

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Check whether the wire from the internal air sensor to the A/C panel is open with a multimeter.

Whether the internal air sensor is open circuit?

YES NO
Check fault points and repair them
Go to Step 4 Go to Step 3

Step 3: Fault of A/C panel;

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
If there is no problem found through checking by step 1, 2, it may be an internal fault of the A/C panel.
6-344
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.15 E15 Air Conditioning Abnormal Alarm E11--Inner Gas Sensor Break Line CLG930E/936E

Is it internal fault of the A/C panel?

YES NO
Replace the A/C panel
Go to Step 4 Go to Step 4
Step 4: Check whether this fault is eliminated.

Inspection method
Operate the machine, and check whether each action is normal.

Has this fault been eliminated?

YES NO
Look for the fault of air conditioning system or
Maintenance is over contact local LiuGong dealers and authorized
service centers.
 6-345
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.16 E18 Air Conditioning Abnormal Alarm E12--Inner Gas Sensor Short Circuit

6.5.16 E18 Air Conditioning Abnormal Alarm E12--Inner Gas Sensor

Short Circuit

Fault SN Main reasons of faults Consequence

Abnormal A/C alarm E12 -- Internal air sensor
E16 The service effect of A/C is poor
short circuit

Fault diagnosis and troubleshooting steps

Step 1: Internal air sensor fault.

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
1. Press OFF on the A/C panel, the LCD does not display, and the A/C stops running;
2. Press the increase and decrease keys of the temperature setting switch in the meantime for over 3
seconds, the LCD will display DTCs;
3. If E12 fault code occurs, check the internal sensor located in the return air valve for short circuit with
a multimeter?
Whether the internal air sensor is short circuit?
YES NO
Replace the internal air sensor.
Go to Step 4 Go to Step 2

Step 2: Internal sensor short-circuited.

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Check whether the wire from the internal air sensor to the A/C panel is short-circuit with a multimeter.

Whether the internal air sensor is short circuit?

YES NO
Check fault points and repair them
Go to Step 4 Go to Step 3
6-346
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.16 E18 Air Conditioning Abnormal Alarm E12--Inner Gas Sensor Short Circuit CLG930E/936E

Step 3: Fault of A/C panel;

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
If there is no problem found through checking by step 1, 2, it may be an internal fault of the A/C panel.

Is it internal fault of the A/C panel?

YES NO
Replace the A/C panel
Go to Step 4 Go to Step 4
Step 4: Check whether this fault is eliminated.

Inspection method
Operate the machine, and check whether each action is normal.

Has this fault been eliminated?

YES NO
Look for the fault of air conditioning system or
Maintenance is over contact local LiuGong dealers and authorized
service centers.
 6-347
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.17 E17 Air Conditioning Abnormal Alarm E17--Water Temperature Sensor Break Line

6.5.17 E17 Air Conditioning Abnormal Alarm E17--Water Temperature

Sensor Break Line

Fault SN Main reasons of faults Consequence

Abnormal A/C alarm E15 -- Water temperature
E17 The service effect of A/C is poor
sensor open circuit

Fault diagnosis and troubleshooting steps

Step 1 Water temperature sensor fault.

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
1. Press OFF on the A/C panel, the LCD does not display, and the A/C stops running;
2. Press the increase and decrease keys of the temperature setting switch in the meantime for over 3
seconds, the LCD will display DTCs;
3. If E15 DTC occurs, check whether the water temperature sensor circuit located in the inflow side of
the warm wind radiator is open with a multimeter.
Whether the water temperature sensor is open circuit?
YES NO
Replace the water temperature sensor.
Go to Step 4 Go to Step 2

Step 2: Water temperature sensor open circuit.

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Check whether the wire from the water temperature sensor to the A/C panel is open circuit with a
multimeter.

Whether the water temperature sensor is open circuit?

YES NO
Check fault points and repair them
Go to Step 4 Go to Step 3
6-348
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.17 E17 Air Conditioning Abnormal Alarm E17--Water Temperature Sensor Break Line CLG930E/936E

Step 3: Fault of A/C panel;

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
If there is no problem found through checking by step 1, 2, it may be an internal fault of the A/C panel.

Is it internal fault of the A/C panel?

YES NO
Replace the A/C panel
Go to Step 4 Go to Step 4

Step 4: Check whether this fault is eliminated.

Inspection method
Operate the machine, and check whether each action is normal.

Has this fault been eliminated?

YES NO
Look for the fault of air conditioning system or
Maintenance is over contact local LiuGong dealers and authorized
service centers.
 6-349
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.18 E18 Air Conditioning Abnormal Alarm E16--Water Temperature Sensor Short Circuit

6.5.18 E18 Air Conditioning Abnormal Alarm E16--Water Temperature

Sensor Short Circuit

Fault SN Main reasons of faults Consequence

Abnormal A/C alarm E16 -- Water temperature
E18 The service effect of A/C is poor
sensor short circuit

Fault diagnosis and troubleshooting steps

Step 1 Water temperature sensor fault.

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
1. Press OFF on the A/C panel, the LCD does not display, and the A/C stops running;
2. Press the increase and decrease keys of the temperature setting switch in the meantime for over 3
seconds, the LCD will display DTCs;
3. If E16 DTC occurs, check whether the water temperature sensor circuit located in the inflow side of
the warm wind radiator is short with a multimeter?
Whether the water temperature sensor is short circuit?
YES NO
Replace the water temperature sensor.
Go to Step 4 Go to Step 2

Step 2: Water temperature sensor short circuit.

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Check whether the wire from the water temperature sensor to the A/C panel is short-circuit with a
multimeter.

Whether the water temperature sensor is short circuit?

YES NO
Check fault points and repair them
Go to Step 4 Go to Step 3
6-350
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.18 E18 Air Conditioning Abnormal Alarm E16--Water Temperature Sensor Short Circuit CLG930E/936E

Step 3: Fault of A/C panel;

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
If there is no problem found through checking by step 1, 2, it may be an internal fault of the A/C panel.

Is it internal fault of the A/C panel?

YES NO
Replace the A/C panel
Go to Step 4 Go to Step 4
Step 4: Check whether this fault is eliminated.

Inspection method
Operate the machine, and check whether each action is normal.

Has this fault been eliminated?

YES NO
Look for the fault of air conditioning system or
Maintenance is over contact local LiuGong dealers and authorized
service centers.
 6-351
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.19 E19 Air Conditioning Abnormal Alarm E18--Solar Sensor Short Circuit

6.5.19 E19 Air Conditioning Abnormal Alarm E18--Solar Sensor Short

Circuit

Fault SN Main reasons of faults Consequence

Abnormal A/C alarm E18 -- solar sensor short
E19 The service effect of A/C is poor
circuit

Fault diagnosis and troubleshooting steps

Step 1: The solar sensor fault (internal fault).

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
1. Press OFF on the A/C panel, the LCD does not display, and the A/C stops running;
2. Press the increase and decrease keys of the temperature setting switch in the meantime for over 3
seconds, the LCD will display DTCs;
3. If E18 DTC occurs, check whether the circuit of the solar sensor is short with a multimeter?
Whether the solar sensor is short circuit?
YES NO
Replace the solar sensor
Go to Step 4 Go to Step 2

Step 2: The solar sensor short-circuited.

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Check whether the solar sensor to the A/C panel is short-circuit with a multimeter

Whether the solar sensor is short circuit?

YES NO
Check fault points and repair them
Go to Step 4 Go to Step 3
6-352
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.19 E19 Air Conditioning Abnormal Alarm E18--Solar Sensor Short Circuit CLG930E/936E

Step 3: Fault of A/C panel;

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
If there is no problem found through checking by step 1, 2, it may be an internal fault of the A/C panel.

Is it internal fault of the A/C panel?

YES NO
Replace the A/C panel
Go to Step 4 Go to Step 4

Step 4: Check whether this fault is eliminated.

Inspection method
Operate the machine, and check whether each action is normal.

Has this fault been eliminated?

YES NO
Look for the fault of air conditioning system or
Maintenance is over contact local LiuGong dealers and authorized
service centers.
 6-353
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.20 E20 Air Conditioning Abnormal Alarm E43--Air Blowing Valve Abnormal

6.5.20 E20 Air Conditioning Abnormal Alarm E43--Air Blowing Valve

Abnormal

Fault SN Main reasons of faults Consequence

Abnormal A/C alarm E43 -- Air blowing valve
E20 The service effect of A/C is poor
abnormal

Fault diagnosis and troubleshooting steps

Step 1 Air-out servo motor fault (internal fault).

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
1. Press OFF on the A/C panel, the LCD does not display, and the A/C stops running;
2. Press the increase and decrease keys of the temperature setting switch in the meantime for over 3
seconds, the LCD will display DTCs;
3. If E43 DTC occurs, check whether the circuit of the air-out servo motor on the evaporator as is
short or open with a multimeter.
Whether the air-out servo motor is faulty?
YES NO
Replace the air-out servo motor
Go to Step 4 Go to Step 2

Step 2: Circuit short circuit of the air-out servo motor;

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Check whether the circuit from the air-out servo motor to the A/C panel is short or open with a
multimeter

Whether the air-out servo motor circuit is faulty?

YES NO
Check fault points and repair them
Go to Step 4 Go to Step 3
6-354
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.20 E20 Air Conditioning Abnormal Alarm E43--Air Blowing Valve Abnormal CLG930E/936E

Step 3: Fault of A/C panel;

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
If there is no problem found through checking by step 1, 2, it may be an internal fault of the A/C panel.

Is it internal fault of the A/C panel?

YES NO
Replace the A/C panel
Go to Step 4 Go to Step 4

Step 4: Check whether this fault is eliminated.

Inspection method
Operate the machine, and check whether each action is normal.

Has this fault been eliminated?

YES NO
Look for the fault of air conditioning system or
Maintenance is over contact local LiuGong dealers and authorized
service centers.
 6-355
December 30, 2017 6.5 Fault Diagnosis of Electrical System
CLG930E/936E 6.5.21 E21 Abnormal Alarm of the A/C E44 – Abnormal Air Mixing Door

6.5.21 E21 Abnormal Alarm of the A/C E44 – Abnormal Air Mixing Door

Fault SN Main reasons of faults Consequence

Abnormal A/C alarm E44 -- Air mixing valve
E21 The service effect of A/C is poor
abnormal

Fault diagnosis and troubleshooting steps

Step 1: Air mixing door (A/M) servo motor fault (internal fault).

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
1. Press OFF on the A/C panel, the LCD does not display, and the A/C stops running;
2. Press the increase and decrease keys of the temperature setting switch in the meantime for over 3
seconds, the LCD will display DTCs;
3. If E44 DTC occurs, check whether the circuit of the air-out servo motor on the evaporator as is
short or open with a multimeter?
Whether the servo motor of the air mixing ventilation door (A/M) is faulty?
YES NO
Replace the servo motor of the air mixing
ventilation door (A/M)
Go to Step 2
Go to Step 4

Step 2: Circuit short circuit of the servo motor of the air mixing door (A/M).

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
Check whether the circuit from the servo motor of the air mixing ventilation door to the A/C panel is
short or open with a multimeter.

Whether the servo motor circuit of the air mixing ventilation door (A/M) is faulty?

YES NO
Check fault points and repair them
Go to Step 4 Go to Step 3
6-356
6.5 Fault Diagnosis of Electrical System December 30, 2017
6.5.21 E21 Abnormal Alarm of the A/C E44 – Abnormal Air Mixing Door CLG930E/936E

Step 3: Fault of A/C panel;

Notice: When replacing the components, please be sure to use LiuGong parts.
Inspection method
If there is no problem found through checking by step 1, 2, it may be an internal fault of the A/C panel.
Is it internal fault of the A/C panel?
YES NO
Replace the A/C panel
Go to Step 4 Go to Step 4

Step 4: Check whether this fault is eliminated.

Inspection method
Operate the machine, and check whether each action is normal.

Has this fault been eliminated?

YES NO
Look for the fault of air conditioning system or
Maintenance is over contact local LiuGong dealers and authorized
service centers.
 6-357
December 30, 2017 6.6 Fault Diagnosis of the Hydraulic System and
Mechanical System

6.6 Fault Diagnosis of the Hydraulic System and Mechanical

System

6.6.1 System Table of the Hydraulic System and Mechanical System

Arm 1 Arm
Arm 2 cylinder

Bucket
cylinder Bucket Spare

Boom Boom
Boom 1 Boom 2 cylinder
cylinder

Travel Swing
motor-lh Travel-lh Swing motor

Straight Travel
Travel-rh motor-rh
travel

P2 (from the pilot

valve XB1)
6-358
6.6 Fault Diagnosis of the Hydraulic System and Mechanical System December 30, 2017
6.6.2 Excessive Barking Angle for H1 Slewing Stop CLG930E/936E

6.6.2 Excessive Barking Angle for H1 Slewing Stop

Excessive braking angle for

slewing stop

Yes

Check whether the slewing

No Slewing relief valve fault
overflow pressure is normal.

Yes

Check whether the anti-reversing No Anti-reversing valve fault

valve is functioning properly.

Yes

Check the slewing pilot Clean and replace the pilot line
valve for clogging Yes

No

Check whether the pilot valve Pilot valve fault

is functioning properly No

Yes

Check whether the

slewing valve element No Spring fault
spring is normal

Yes

Swing motor fault

 6-359
December 30, 2017 6.6 Fault Diagnosis of the Hydraulic System and
Mechanical System

6.6.3 Abnormal Noise from H2 Pump Mounting Position

Abnormal sound of pump

mounting position

Yes

Check the flywheel inside Coupling components:

Yes
for foreign matters Removal and repair

No

Check the coupling hub spline for

Replace the hub or tighten
wear and the adjusting screw for Yes the adjusting screw.
fixing the hub for looseness.

This abnormal sound may be

caused by the hydraulic pump or
No the engine itself. Refer to the
operating instructions of the
device and the engine.
6-360
6.6 Fault Diagnosis of the Hydraulic System and Mechanical System December 30, 2017
6.6.4 H3 Start the Engine, and All Operations have no Response CLG930E/936E

6.6.4 H3 Start the Engine, and All Operations have no Response

When the engine is

started, all operations
are unresponsive.

Yes

Check whether the

Add oil to the specified
hydraulic oil level is No level as required.
normal.

No
The hydraulic pump Hydraulic pump fault:
sounds abnormally. Yes Remove and repair it.
Check whether the abnormal Yes
sound comes from the
hydraulic pump or pump
installation position. Yes

The pump installation position Troubleshoot by

No sounds abnormally. Yes referring to H2.

Check whether the pilot Check whether any oil flows Pilot relief valve fault:
pressure is normal. No out from the pilot pump. Yes
Repair or replace it

Pilot pump fault:

Remove and repair it.

No

Pilot valve or main

Check the pilot line for No control valve fault:
clogging or leakage.
Remove and repair it.

Clean the pilot line or

Yes
repair it.
 6-361
December 30, 2017 6.6 Fault Diagnosis of the Hydraulic System and
Mechanical System

6.6.5 H4 Hydraulic Oil Emulsification,

Hydraulic oil
emulsification

Yes

Sample the oil and drop the Let the hydraulic oil sit
This may be due
sample droplets onto the hot for a period of time, and
Yes to water in the
iron plate, and then check remove the water or
hydraulic oil.
for bubbles. replace the oil.

Check the suction line

This may be due and the return line, and
Yes
to air in the cut off the air-mixed
hydraulic oil. source.
6-362
6.6 Fault Diagnosis of the Hydraulic System and Mechanical System December 30, 2017
6.6.6 H5 Abnormal Hydraulic Oil Temperature Rise CLG930E/936E

6.6.6 H5 Abnormal Hydraulic Oil Temperature Rise

Abnormal hydraulic oil

temperature rise

Yes

Check whether the

Add oil to the specified
hydraulic oil level is No level as required.
normal.

Yes

Check the oil cooler for Clean the oil cooler to

Yes keep the air ventilated.
clogging.

No

Check whether the fan

Adjust the belt tension
belt tension is No or replace the belt.
appropriate or not.

Yes

Check whether the pressure

of the main relief valve, the Adjust the setting
port relief valve and the Yes pressure again.
motor relief valve is lower
than the standard value.

No

Check whether the oil

No The check valve is
return check valve is
failed. Replace it.
normal.
 6-363
December 30, 2017 6.6 Fault Diagnosis of the Hydraulic System and
Mechanical System

6.6.7 H6 Slewing abnormally to Left and Right Directions

Slewing abnormally to
left and right directions

Yes

Whether other Troubleshoot it by referring to the

operation is Yes method that for Unidirectional
unresponsive or not? Revolving Operation Is Unresponsive.

No

Check whether the Check whether the The swing valve

swing pilot pressure is Yes swing valve element Yes element gets stuck:
normal. gets stuck. Remove and repair it.

No

Check whether the Repair or replace the

swing relief valve is No swing relief valve.
functioning properly.
No

Yes

Swing motor and

reducer fault: Repair
or replace it.

Check whether the Swing pilot valve fault:

No
swing pilot valve is Remove, repair or
functioning properly. replace it.

Yes

Clogging or leakage Yes

Clean or replace the
inside the pilot line pilot line.
6-364
6.6 Fault Diagnosis of the Hydraulic System and Mechanical System December 30, 2017
6.6.8 H7 No Response for Slewing Single Direction Operation CLG930E/936E

6.6.8 H7 No Response for Slewing Single Direction Operation

No reponse for
slewing single
direction opeation

Yes

Check whether the

left swing pilot Check the pilot line inside Pilot valve fault:
No No
pressure is the same for clogging or leakage. Remove and repair it.
as the right one.

Yes Yes
Clogging or Clean or repair the
leakage occurs. pilot line.

Check whether the

The swing valve element
swing valve element Yes
gets stuck: Remove it,
gets stuck.

Swing relief valve fault:

No
Remove, repair or replace it.
 6-365
December 30, 2017 6.6 Fault Diagnosis of the Hydraulic System and
Mechanical System

6.6.9 H8 Swing cannot be Stopped

Rotation unable to stop

Yes

Check whether the swing Check whether the swing valve

No No Spring fault: Remove or replace it.
valve element is in the element spring is normal
neutral position.
Yes

Check whether the swing valve The swing valve element gets stuck:
element gets stuck. Yes Remove or replace it.

No

Check whether the swing pilot Swing pilot valve fault:

No
pressure is normal. Remove or replace it.

Yes

Check whether the pilot Pilot relief valve fault:

No
pump pressure is normal. Remove, repair or replace it.

No Yes Pilot pump fault:

Remove and repair it.

Check whether the

swing relief valve Swing relief valve fault:
No Remove or replace it.
pressure is normal.
6-366
6.6 Fault Diagnosis of the Hydraulic System and Mechanical System December 30, 2017
6.6.10 H9 Fail to Actuate Unilateral Travel Mechanism CLG930E/936E

6.6.10 H9 Fail to Actuate Unilateral Travel Mechanism

Fail to actuate
unilateral travel
mechanism

Yes

Whether other Check whether the The travel valve

operation is No travel valve element Yes element gets stuck:
unresponsive or not? gets stuck. Remove and repair it.

No

Check whether the Clean or replace the pilot

travel pilot pressure is Travel pilot line and
No line. Travel pilot valve fault:
normal. pilot valve fault
Remove, repair or replace it.

Yes

Yes Check whether the The travel motor balance

travel motor balance Yes valve gets stuck: Remove,
valve gets stuck. repair or replace it.

No

Travel motor and

reducer fault: Remove
and repair it.

Troubleshoot
according to H3.
 6-367
December 30, 2017 6.6 Fault Diagnosis of the Hydraulic System and
Mechanical System

6.6.11 H10 Travel Deviation

Travel deviation

Yes

Let both left and right sides of

the excavator travel at the same
Check whether the travel spool Travel spool fault: Remove and
time in the same direction+ any Yes Yes
gets stuck. repair
movement on the upper part,
whether pulling one side or not?
No

Check whether the travel pilot Travel pilot line and pilot valve fault:
pressure is normal. No Clean, repair and replace it.

Yes

No Check whether the center joint is Center joint fault: Remove,

No
functioning properly. repair or replace it.
No
Yes

Check whether the travel motor Travel motor fault:

No Remove and repair it.
is functioning properly.

Yes

Main control valve fault:

Remove, repair or replace it.

Exchange the left pump output

hose and negative feedback
Hydraulic pump fault:
hose with the right ones, and Yes Remove and repair it.
check whether the fault
phenomenon transfers.
6-368
6.6 Fault Diagnosis of the Hydraulic System and Mechanical System December 30, 2017
6.6.12 H11 Slow Speed of the Boom, Arm or Bucket CLG930E/936E

6.6.12 H11 Slow Speed of the Boom, Arm or Bucket

Slow speed of the boom,

arm or bucket

Yes

Whether the engine Adjust the engine

No
speed is normal speed.

Yes

Check whether the left Check whether both the

and right traveling left speed and the right Yes Main pump fault:
No
speeds are normal. speed are slow. Remove and repair it.

No

Check whether the Check the pilot line

Clean or repair
boom, arm or bucket No inside for clogging or Yes the pilot line.
pilot pressure is normal. leakage.

Yes No

Check whether the pilot valve is Pilot valve fault:

No
functioning properly Remove and repair it.

Check whether the

Check whether the pilot Just as above-mentioned,
confluence is normal when
the boom rising or the arm No pressure of the boom (2) No check the pilot line and
expanding. or the arm (2) is normal. pilot valve.

Yes
Check whether the
Check whether the
confluent valve element
above-mentioned valve Yes
spring is functioning
element gets stuck.
properly.
No
Yes
Confluent valve element
gets stuck: Remove and No Replace spring
repair it.

Check whether the boom, Check the pilot line Pilot valve fault:
arm or bucket pilot pressure No inside for clogging or No Remove and repair it.
is normal. leakage.

Clean or repair the

Yes Yes pilot line.

Check whether the Valve element gets

above-mentioned valve Yes stuck: Remove or
element gets stuck. replace

No
Check whether the main
relief valve and the port relief Relief valve fault: Remove,
valve are functioning No repair or replace it.
properly.

Cylinder inside damage:

Yes Remove and repair it.
 6-369
December 30, 2017 6.6 Fault Diagnosis of the Hydraulic System and
Mechanical System

6.6.13 H12 Weak Actions of the Boom, Arm or Bucket

Weak actions of the

boom, arm or
bucket

Yes

Check whether the Main relief valve fault: Adjust

main relief valve No the pressure, and repair or
pressure is normal. replace the valve.

Yes

Check whether the Port relief valve fault: Adjust

port relief valve No the pressure, and repair or
pressure is normal. replace the valve.

Yes

Check whether the cylinder Cylinder fault:

No
leakage rate is normal. Remove and repair it.

Troubleshoot according to
Yes
the H11 fault.
6-370
6.6 Fault Diagnosis of the Hydraulic System and Mechanical System December 30, 2017
6.6.14 H13 Significantly Reduced Engine Speed or Engine Stalling CLG930E/936E

6.6.14 H13 Significantly Reduced Engine Speed or Engine Stalling

Turn off the engine, make preparations, rotate the engine at high speed and then take fault
diagnosis.
Check the harness connectors for looseness in advance.

Significantly reduced engine

speed or engine stalling,
Check whether the system
shutdown Yes No Main relief valve fault
pressure is normal.

Yes

Check whether the main Pump proportional

pump proportional valve is No valve fault: Repair
functioning properly. or replace it.

Yes

Engine or electronic control

system fault
 7-1
December 30, 2017 Removal and Installation
CLG930E/936E

Removal and Installation

7.1 Overview.....................................................................................................................7-3
7.1.1 General Torque Specifications......................................................................................................7-3
7.1.2 Coating Material ............................................................................................................................7-8

7.2 Power System ............................................................................................................7-9

7.2.1 Removal and Installation of Diesel Engine Assembly ...................................................................7-9
7.2.2 Removal and Installation of the Hydraulic Oil Radiator...............................................................7-17
7.2.3 Removal and Installation of the Intercooler.................................................................................7-20
7.2.4 Removal and Installation of Water Radiator................................................................................7-23
7.2.5 Removal and Installation of the Fuel Tank Assembly .................................................................7-27
7.2.6 Removal and Installation of the Injector ......................................................................................7-30
7.2.7 Removal and Installation of the Engine Front Seal .....................................................................7-32
7.2.8 Removal and Installation of the Engine Rear Seal .....................................................................7-34
7.2.9 Removal and Installation of the Cylinder Head Assembly ..........................................................7-36

7.3 Track Travel System................................................................................................7-41

7.3.1 Removal and Installation of the Track Roller ..............................................................................7-41
7.3.2 Removal and Installation of the Carrier Roller ............................................................................7-43
7.3.3 Removal and Installation of the Track Assembly ........................................................................7-45
7.3.4 Removal and Installation of the Sprocket ...................................................................................7-47
7.3.5 Removal and Installation of the Idler Assembly and Tensioner Assembly..................................7-48
7.3.6 Removal and Installation of the Revolving Frame.......................................................................7-50
7.3.7 Removal and Installation of the Swing Bearing ..........................................................................7-52

7.4 Covering Parts .........................................................................................................7-54

7.4.1 Removal and Installation of the Engine Hood .............................................................................7-54
7.4.2 Removal and Installation of the Counterweight ..........................................................................7-56

7.5 Hydraulic System ....................................................................................................7-58

7.5.1 Removal and Installation of Center Joint ....................................................................................7-58
7.5.2 Disassembly and Assembly of the Center Joint..........................................................................7-61
7.5.3 Removal and Installation of Hydraulic Oil Tank ..........................................................................7-65
7.5.4 Removal and Installation of Main Control Valve Assembly.........................................................7-69
7.5.5 Disassembly and Assembly of the Main Control Valve...............................................................7-73
7.5.6 Removal and Installation of Main Pump Assembly .....................................................................7-91
7-2
Removal and Installation December 30, 2017
CLG930E/936E

7.5.7 Removal and Installation of Main Pump Assembly .....................................................................7-95

7.5.8 Disassembly and Assembly of PTO Pump ...............................................................................7-110
7.5.9 Removal and Installation of the Travel Pilot Valve Assembly ...................................................7-119
7.5.10 Disassembly and Assembly of Travel Pilot Valve ...................................................................7-122
7.5.12 Removal and Installation of Hand Pilot Valve Assembly.........................................................7-147
7.5.12 Disassembly and Assembly of the Hand Pilot Valve Assembly ..............................................7-150
7.5.13 Removal and Installation of the Travel Motor & Reduction Gear, ...........................................7-169
7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear .......................................7-174
7.5.15 Removal and Installation of the Swing Motor & Reduction Gear ............................................7-211
7.5.16 Disassembly and Assembly of the Swing Motor & Reduction Gear........................................7-215

7.6 Work Implement.....................................................................................................7-242

7.6.1 Removal and Installation of the Bucket.....................................................................................7-242
7.6.2 Removal and Installation of Link and Lever ..............................................................................7-245
7.6.3 Removal and Installation of Arm ...............................................................................................7-248
7.6.4 Removal and Installation of the Boom ......................................................................................7-250
7.6.5 Removal and Installation of the Work Implement Assembly .....................................................7-255
7.6.6 Removal and Installation of Bucket Cylinder Assembly ............................................................7-258
7.6.7 Removal and Installation of Arm Cylinder Assembly ................................................................7-262
7.6.8 Removal and Installation of Boom Cylinder Assembly..............................................................7-266
7.6.9 Disassembly and Assembly of Cylinder ....................................................................................7-270

7.7 Air Conditioning System.......................................................................................7-278

7.7.1 Removal and Installation of A/C Evaporator Assembly.............................................................7-278
7.7.2 Removal and Installation of A/C Compressor Assembly...........................................................7-284

7.8 Cab..........................................................................................................................7-287
7.8.1 Removal and Installation of Cab ...............................................................................................7-287
7.8.2 Removal and Installation of Floor Frame Assembly..................................................................7-293
 7-3
December 30, 2017 7.1 Overview
CLG930E/936E 7.1.1 General Torque Specifications

7.1 Overview

This chapter introduces the removal and installation methods for main parts of this machine.
The removal and installation of a component introduce the methods for removing and installing the
component from and on the complete machine. The disassembly and assembly of a component
introduce the method for disassembling the component into subcomponents and the method of
assembling them.

7.1.1 General Torque Specifications

Bolts involved in this machine shall be tightened in accordance with the torque requirements specified in
the following table, unless special declaration.
CLG 930E excavator bolt torque chart

Bolt Wrench size Torque

No. Description
specification (mm)
N.m lbf·ft
Captive bolt of the engine shock M24-10.9 36 900 663.8
1
absorber M20-10.9 30 550 405.6
115 (Cylinder
84.8 (Cylinder
block)
block)
2 Captive bolt of engine mounting M12-10.9 18 50 (Aluminum
36.9 (Aluminum
flywheel
flywheel housing)
housing)
3 Bolt on flywheel housing M10-10.9 16 65 47.9
4 Captive bolt of water tank bracket M16-10.9 24 305 224.9
5 Captive bolt of fuel tank M16-10.9 24 305 224.9
6 Captive bolt of hydraulic oil tank M16-10.9 24 305 224.9
7 Captive bolt of pump M20-10.9 17Inner hexagon 600 442.5
8 Captive bolt of main control valve M12-10.9 18 120 88.5
9 Captive bolt of slewing reducer M24-10.9 36 1020 752.3
10 Captive bolt of swing motor M20-10.9 17Inner hexagon 430 317.1
11 Captive bolt of battery M10-8.8 16 52 38.4
12 Captive bolt of cab M20-10.9 30 600 442.5
Captive bolt of revolving frame
13 M24-10.9 36 1020 752.3
and swing bearing
Captive bolt of underframe swivel
14 M24-10.9 36 1020 752.3
bearing
15 Captive bolt of the travel reducer M24-10.9 36 1020 752.3
16 Captive bolt of sprocket M20-10.9 30 600 442.5
17 Captive bolt of carrier roller M18-10.9 27 415 306.1
18 Captive bolt of track roller M20-10.9 30 600 442.5
19 Captive bolt of track shoe M24-12.9 36 800 590
7-4
7.1 Overview December 30, 2017
7.1.1 General Torque Specifications CLG930E/936E

CLG 930E excavator bolt torque chart

20 Captive bolt of track guard M22-10.9 34 800 590
21 Mounting bolt of counterweight M42-10.9 65 4600 3392.5

CLG 936E excavator bolt torque chart

Bolt Wrench size Torque

No. Description
specification (mm) N.m lbf·ft
Captive bolt of the engine shock
1 M24-10.9 36 900 663.8
absorber
84.8 (Cylinder
115 (Cylinder
block)
block)
36.7
2 Captive bolt of engine mounting M12-10.9 18 50 (Aluminum
(Aluminum
flywheel
flywheel
housing)
housing)
3 Bolt on flywheel housing M10-10.9 16 30 22.1
Captive bolt of water tank
4 M16-10.9 24 305 224.9
bracket
5 Captive bolt of fuel tank M16-10.9 24 305 224.9
6 Captive bolt of hydraulic oil tank M16-10.9 24 305 224.9
17Inner
7 Captive bolt of pump M20-10.9 600 442.5
hexagon
Captive bolt of main control
8 M12-10.9 18 120 88.5
valve
9 Captive bolt of slewing reducer M24-10.9 36 1020 752.3
17Inner
10 Captive bolt of swing motor M20-10.9 600 442.5
hexagon
11 Captive bolt of battery M10-8.8 16 52 38.4
12 Captive bolt of cab M20-10.9 30 600 442.5
Captive bolt of revolving frame
13 M24-10.9 36 800 590
and swing bearing
Captive bolt of underframe
14 M24-10.9 36 800 590
swivel bearing
Captive bolt of the travel
15 M24-10.9 36 800 590
reducer
16 Captive bolt of sprocket M20-10.9 30 600 442.5
17 Captive bolt of carrier roller M18-10.9 27 415 306.1
18 Captive bolt of track roller M20-10.9 30 600 442.5
19 Captive bolt of track shoe M24-12.9 36 800 590
20 Captive bolt of track guard M24-10.9 36 1020 752.3
21 Mounting bolt of counterweight M42-10.9 65 4600 3392.5
 7-5
December 30, 2017 7.1 Overview
CLG930E/936E 7.1.1 General Torque Specifications

Tightening torque of 24°cone with O-ring sealed pipe fittings

Hose inner Tightening torque

Series Thread size diameter
mm N.m kgf.m
M12×1.5 5 16±1 1.6±0.1
M14×1.5 6.3 16±1 1.6±0.1
M16×1.5 8 26±2 2.7±0.2
M18×1.5 10 37±2 3.8±0.2
M22×1.5 12.5 47±2 4.8±0.2
Light-type
M26×1.5 16 89±4 9.1±0.4
M30×2 19 116±5 11.8±0.5
M36×2 25 137±6 14.0±0.6
M45×2 31.5 226±11 23.1±1.1
M52×2 38 347±16 35.4±1.6
M14X1.5 5 26±2 2.7±0.2
M16X1.5 6.3 42±2 4.3±0.2
M18X1.5 6.3 53±2 5.4±0.2
M20X1.5 8 63±3 6.4±0.3
M22X1.5 10 79±4 8.1±0.4
Heavy-type
M24X1.5 12.5 84±4 8.6±0.4
M30X2 16 126±6 12.9±0.6
M36X2 19 179±8 18.3±0.8
M42X2 25 263±12 26.8±1.2
M52X2 31.5 368±17 37.6±1.7
7-6
7.1 Overview December 30, 2017
7.1.1 General Torque Specifications CLG930E/936E

Tightening torque of flange seal pipe joint bolt

Bolt Tightening torque

Series Bolt performance
level N.m kgf.m

M8 25.2±1.2 2.57±0.12

M10 52.5±2.5 5.36±0.26

8.8
M12 96.6±4.6 9.86±0.47

M16 220±10 22.4±1.02

Light-type
M8 33.6±1.6 3.43±0.16

M10 73.5±3.5 7.50±0.36

10.9
M12 136±6 13.88±0.61

M16 310±15 31.63±1.53

M8 25.2±1.2 2.57±0.12

M10 52.5±2.5 5.36±0.26

M12 8.8 96.6±4.6 9.86±0.47

M16 220±10 22.45±1.02

M20 420±20 42.86±2.0

Heavy-type
M8 33.6±1.6 3.43±0.16

M10 73.5±3.5 7.5±0.36

M12 10.9 136±6 13.88±0.6

M16 310±15 31.63±1.53

M20 577±27 58.88±2.76

 7-7
December 30, 2017 7.1 Overview
CLG930E/936E 7.1.1 General Torque Specifications

Tightening torque of thread angle type sealed hose connector

Material of
Carbon steel and alloy steel Aluminum product
fastenings
Tightening torque Tightening torque
Thread size
N.m kgf.m N.m kgf.m
G1/8 8.75±1.25 0.90±0.12 / /
G1/4 36±2 3.67±0.2 29.3±2.2 3.0±0.2
G3/8 73.5±4.5 7.5±0.46 49±3 5.0±0.3
G1/2 110±10 11.2±1.0 55±5 5.6±0.5
G3/4 165±15 16.8±1.5 74±4 7.5±0.4
G1 225±25 23.0±2.55 / /
G1-1/4 275±25 28.0±2.55 / /
G1-1/2 285±15 29.1±1.5 / /

Connector tightening torque

Tightening torque
Thread size
N.m kgf.m
M12 24±2 2.4±0.2

M14 30±2 3.1±0.2

M16 30±2 3.1±0.2

M18 30±2 3.1±0.2

7-8
7.1 Overview December 30, 2017
7.1.2 Coating Material CLG930E/936E

7.1.2 Coating Material

Name Specifications Main features and purposes

Features: anaerobic and fast air drying
1277 Thread locker 1277
Purposes: used for parts not frequently removed
1243 Thread locker 1243 Used for removable parts (speed sensor in general)
Features: rust protection for a long time,
LONG#2 light
Long-term anti-rust agent Purposes: used for mounting face of main pump, sensor, hydraulic
yellow
fitting, etc.
Molybdenum disulfide
2# Lubrications for swing bearing and pin shaft of work implement
lithium grease 2#
Features: strong ability of cleaning
High efficient detergent 1755 1755
Purposes: used for main pump, swing motor and travel motor
Features: heat absorption and vaporization
Refrigerant R134a
Purposes: used for fluorine filling of air conditioner, etc.
Feature: High-temperature resistance, self-lubrication, medium
resistance, used for medium (sealing oil, air, vapor, water) pipeline
Anaerobic pipe thread
1567 cone / taper thread
sealant
Purposes: used for water temperature sensor and engine oil
pressure sensor
Cleaning agent for
electromechanical HD-10 Used for cleaning oil pipe connectors, etc.
equipment
Diesel engine sealant 1515 Used for mounting face of diesel engine flange

Polyurethane sealant 1924 Used for waterproof of starter motor and assembling clearance

Mobilux EP None Used for rust protection of rear cover hinge

 7-9
December 30, 2017 7.2 Power System
CLG930E/936E 7.2.1 Removal and Installation of Diesel Engine Assembly

7.2 Power System

7.2.1 Removal and Installation of Diesel Engine Assembly

Removal

Before removal, remove the battery negative pole (-) cable first in order to avoid generating
electric arcs.
When the machine is under operation, the antifreeze is in the high-temperature state. Make sure
the diesel engine stops working and antifreeze is cooled before removing the water radiator or
opening the water radiator cap in order to prevent possible personal injuries.
Before removal, rotate the machine revolving frame to an angle suitable for removal, park the
machine on flat and hard ground, and lower and shut down the work implement.

Figures Procedure
1. Remove the engine hood (1). Refer to
"Removal and Installation of Engine hood" in
this chapter for details.
7-10
7.2 Power System December 30, 2017
7.2.1 Removal and Installation of Diesel Engine Assembly CLG930E/936E

Figures Procedure
2. Remove three bottom plates (2), (3) and (4).

3. Prepare a container for receiving antifreeze,

open water drain valve (5), and discharge
antifreeze in the water radiator. Open water
tank cover to accelerate water discharge time.
Notice: Open water tank cover to
accelerate water discharge time. The capacity
of anti-freeze in the cooling system is about 3
L. It is forbidden to directly drain the anti-
freeze to ground to prevent from contaminating
the environment.
5

Notice: For safety operation, firstly make

sure the battery negative (-) cable is removed,
and then go to the next step.
4. Disconnect the negative (-) ground harness (6)
and the positive (+) connecting harness (7)
from the starter motor.
 7-11
December 30, 2017 7.2 Power System
CLG930E/936E 7.2.1 Removal and Installation of Diesel Engine Assembly

Figures Procedure
5. Disconnect the water pipe at upper part of the
engine, and disconnect the refill water pipe (8)
9 and the water outlet pipe (9), respectively.

10 6. Disconnect the degassing pipe(10) and the A/

C heater intake pipe (11);

11
7. Remove the inter-cooler steel pipes (12) and
12 (13).
8. Remove the turbocharger intake hose (14);
Notice: After disconnecting the intake
line, the pipe lines and the air inlets of the
engine must be masked to prevent engine wear
13 due to dust and other foreign matters entering
the air intake system.

14

9. Remove the connecting harness from the

alternator(15) .
10. Disconnect the harness connector (16) of
15 water temperature sensor;
11. Remove the harness fixing support (17)
assembled on the engine mounting.

16

17
7-12
7.2 Power System December 30, 2017
7.2.1 Removal and Installation of Diesel Engine Assembly CLG930E/936E

Figures Procedure
12. Disconnect the frame harness from the engine:
(1) Disconnect the A/C compressor harness
connector (18);
18
(2) Disconnect the air intake heater harness (19);
(3) Disconnect the choke solenoid connector (20);
(4) 1 Disconnect the frame harness mounting
19 support (21);
(5) 1 Disconnect the speed sensor connector (22);

21 20

22

13. Remove the fan guard (23);

23
 7-13
December 30, 2017 7.2 Power System
CLG930E/936E 7.2.1 Removal and Installation of Diesel Engine Assembly

Figures Procedure
14. Remove the cooling pipe from the A/C
compressor (24).
(1) If the the mounting bracket of the A/C
compressor can be removed directly without
removal of the cooling pipe, remove. Remove
the mounting bracket together with the A/C
compressor from the engine, and fix them to
24 the side.
(2) If the cooling pipe needs to be removed, refer
to the Removal of A/C Compressor Assembly
for the detailed procedures.
Notice: Before the cooling pipe is
removed, collect the refrigerant with the
automatic refrigerant recovery equipment.
15. Remove the engine fan (25);

25

16. Disconnect the connecting water hose at the

27 lower part of the engine:
(1) Disconnect the engine water supply hose (26),
(2) Disconnect the A/C water return pipe (27);

26
7-14
7.2 Power System December 30, 2017
7.2.1 Removal and Installation of Diesel Engine Assembly CLG930E/936E

Figures Procedure
17. Remove the water filter fixing bracket (28) from
the covering parts pillar and bind the water filter
on the engine to avoid interference during
hoisting of engine;

28

18. Remove the covering parts baffle around the

muffler;
(1) Remove the air grill (29);
29 (2) Remove the main pump baffle(30);
(3) Remove the baffle (31) near the right rear
engine mounting;
30

31

19. Close the fuel shutoff valve (32) of the fuel

lines;

32
 7-15
December 30, 2017 7.2 Power System
CLG930E/936E 7.2.1 Removal and Installation of Diesel Engine Assembly

Figures Procedure
20. Remove the engine oil inlet pipe (34);
21. Remove the engine oil return pipe (33) and its
fixing bracket(35);
Notice: When removing the oil return pipe
on the engine, the oil port must be plugged or
33 34 the oil return pipe must be fixed at a position
above the fuel liquid level in the fuel tank in
order to prevent fuel in the fuel tank backflow.
After removing the fuel line, the oil ports on the
line and on the engine must be masked to
35
prevent engine damage due to dust and other
foreign matters entering the fuel system.

22. Remove the two oil pipes (36) ,(37) from oil
filter;
36 Notice: A little oil will leak during removal
of oil pipe and needs to be collected with
container to avoid polluting the environment;
Notice: The pipe and filter inlet & outlet
shall be sealed after removal of oil pipe to
37 avoid foreign matters entering into lubrication
system, resulting in engine damaged.

23. Lift the main pump (38) with a lifting sling, and
remove flange plate (39)
Install the bolts, and move the main pump and the
flange outwards together so that the coupling
bushing is separated from the engine flywheel.

38
39
7-16
7.2 Power System December 30, 2017
7.2.1 Removal and Installation of Diesel Engine Assembly CLG930E/936E

Figures Procedure
24. Remove 4 shock absorber mounting bolts (40)
on the engine bracket.

40

25. Check the components around the engine,

slowly lift the diesel engine (41) after making
41 sure lifting has no effect on them, and put it in a
safe place.
 7-17
December 30, 2017 7.2 Power System
CLG930E/936E 7.2.2 Removal and Installation of the Hydraulic Oil Radiator

Installation

The installation sequence of the diesel engine is just opposite to its removal sequence.
Properly clean the air intake line before assembly.
For tightening torques in specific positions, execute the following table, and the others are subject to
general tightening torque;
Refill antifreeze, restore the assembly of the negative battery cable, operate the engine, check the line
for leakages and check whether the water radiator is filled with antifreeze.
With regard to table for the bolt tightening torque at special position, see 2.3.1.

If remove the coupling sleeve from the main pump, the main pump spline should be aligned with
the coupling sleeve when assembling.

7.2.2 Removal and Installation of the Hydraulic Oil Radiator

Removal

Before removal, rotate the machine revolving frame to an angle suitable for removal, lower the
work implement to ground, shut down to park the machine, relieve accumulator pressure, open
the hydraulic oil tank cover to relieve pressure inside, and pump out the hydraulic oil from tank.
Before removal, remove the negative (-) battery cable first in order to avoid electric arcs.

Seal up the lines, fittings or hoses with plugs or caps when they are in disassembling state, in
order to prevent pollution source from entering the hydraulic system.
Clean the area around the assembly oil ports before removing lines, fittings or hoses.
7-18
7.2 Power System December 30, 2017
7.2.2 Removal and Installation of the Hydraulic Oil Radiator CLG930E/936E

Figures Procedure
1. Rotate the machine revolving frame to an
angle suitable for removal, lower the work
implement to ground, shut down to park the
machine, relieve accumulator pressure, open
the hydraulic oil tank cover to relieve pressure
in the oil tank, and pump out hydraulic oil in the
oil tank.
1
2. Remove the engine hood (1); and refer to
"Removal and Installation of Engine hood" in
this chapter for details.

3. Remove the air baffle (2) and sealing sponge

(3) from the upper of the radiator.

4. Remove the outlet pipe joint (4) and the bottom

inlet steel pipe (5) from the hydraulic oil
radiator.
Notice: After removing the oil inlet and
outlet pipe of the hydraulic oil radiator, check
whether the O-ring at the oil port is damaged.
replace it timely if it damaged, so as to prevent
oil leakages after assembly is restored.
 7-19
December 30, 2017 7.2 Power System
CLG930E/936E 7.2.2 Removal and Installation of the Hydraulic Oil Radiator

Figures Procedure
5. Remove the mounting bolts (6) on the side of
the hydraulic oil radiator.

6. Hook the hydraulic oil radiator (7) with a steel

wire rope, and slowly lift it out of the radiator
frame.
Notice: Be careful not to scratch the
hydraulic oil radiator core during lifting.
Prevent the oil port flange face from being
scratched. Failure to do so can cause oil
leakage after reassembly.

Installation

The installation sequence is just opposite to the removal sequence.

Clean the components to be assembled properly before assembly.
The tightening torque shall be in accordance with the general specifications;
Refill hydraulic oil. Fill the hydraulic oil to the specified level via the filler. Restore the assembly of the
negative battery cable, operate the engine, make hydraulic oil circulate in the hydraulic system, check
the oil level once again and check the line for leakages.
7-20
7.2 Power System December 30, 2017
7.2.3 Removal and Installation of the Intercooler CLG930E/936E

7.2.3 Removal and Installation of the Intercooler

Removal

1. Before removal, park the machine on flat and hard ground, and lower and shut down the work
implement.
2. Before removal, remove the battery negative pole (-) cable first in order to avoid electric arcs.

After removing the air intake line, the air inlet of the intercooler, intercooler pipe and engine must
be masked immediately to prevent dust and other foreign matters from entering the air intake
system to cause engine wear.

Figures Procedure
1. Turn the revolving frame to the desired angle
for removal. Remove the air prefilter (1), the air
filter cover (2), the engine hood (3), the air grill
(4) and left rear door (5).
 7-21
December 30, 2017 7.2 Power System
CLG930E/936E 7.2.3 Removal and Installation of the Intercooler

Figures Procedure
2. Remove the bracket, sealing sponge (6),
crossbeam (7) and inter-cooler pipe (8).

3. Remove the intercooler hose (9).

4. Remove the overflow pipe (10).
5. Remove left rear bracket (11).

6. Loosen the mounting bolts (12) on both sides

of the intercooler, but do not remove the bolts.
7-22
7.2 Power System December 30, 2017
7.2.3 Removal and Installation of the Intercooler CLG930E/936E

Figures Procedure
7. Hang the inter-cooler (13) with the rope.
Remove the mounting bolts (12) and remove
the intercooler from the radiator assembly
horizontally and gradually, and then rotate it to
the desired angle and take it down from the
engine.
Notice: During this period, be sure to
prevent the intercooler core from being
scratched.

Installation

The installation sequence is just opposite to the removal sequence.

Clean the components to be assembled properly before assembly.
The tightening torque shall be in accordance with the general specifications;
Refill antifreeze, restore the assembly of the negative battery cable, operate the engine, check the line
for leakages and check whether the water radiator is filled with antifreeze.
 7-23
December 30, 2017 7.2 Power System
CLG930E/936E 7.2.4 Removal and Installation of Water Radiator

7.2.4 Removal and Installation of Water Radiator

Removal

Before removal, rotate the machine revolving frame to an angle suitable for removal, park the
machine on flat and hard ground, and lower and shut down the work implement.

Before removal, remove the battery negative pole (-) cable first in order to avoid electric arcs.
When the machine is under operation, the antifreeze is in the high-temperature state. Make sure
the diesel engine stops working and antifreeze is cooled before removing the water radiator or
opening the water radiator cap in order to prevent possible personal injuries.

Figures Procedure
1. Remove the engine hood (1). Refer to
"Removal and Installation of Engine hood" in
this chapter for details.

1
7-24
7.2 Power System December 30, 2017
7.2.4 Removal and Installation of Water Radiator CLG930E/936E

Figures Procedure
2. Remove the bottom plate (2) under the
radiator;

3. Prepare an appropriate container to receive

and contain the antifreezing solution (about
37L in the cooling system)
4. Open the drain valve (3), and then drain the
anti-freeze in the radiator (opening and
removing the radiator cap can accelerate the
drainage time).
Do not drain the anti-freeze onto the
ground to avoid polluting the environment.

5. Remove the air baffle (4) and sealing sponge

(5) at the upper part of the radiator.
 7-25
December 30, 2017 7.2 Power System
CLG930E/936E 7.2.4 Removal and Installation of Water Radiator

Figures Procedure
6. Disconnect the overflow pipe (6), the
degassing pipe (7), the water inlet pipe (8) and
the water refill pipe (9) from the water radiator.
7. Remove the air shroud upper cover plate(10) .
8. If the coolant level sensor is installed, pull out
the sensor connector.

9. Disconnect the water outlet pipe (11) from the

lower part of the radiator, and remove the lower
cover from the air shroud (12).

10. Disconnect the mounting bolts (13) on the side

of the water radiator.
7-26
7.2 Power System December 30, 2017
7.2.4 Removal and Installation of Water Radiator CLG930E/936E

Figures Procedure
11. Hook the water radiator (14) with a steel wire
rope, and lift it out of the radiator frame.
Notice: Be careful not to scratch the water
radiator core during lifting.

Installation

The installation sequence is just opposite to the removal sequence.

Clean the components to be assembled properly before assembly.
The tightening torque shall be in accordance with the general specifications;
Refill antifreeze, restore the assembly of the negative battery cable, operate the engine, check the line
for leakages and check whether the water radiator is filled with antifreeze.
 7-27
December 30, 2017 7.2 Power System
CLG930E/936E 7.2.5 Removal and Installation of the Fuel Tank Assembly

7.2.5 Removal and Installation of the Fuel Tank Assembly

Removal

Before removal, park the machine on flat and hard ground, and lower and shut down the work
implement.
Before removal, remove the negative (-) battery cable first in order to avoid electric arcs.

Prepare two appropriate fuel drums for receiving fuel during disassembly which can be reused.

Figures Procedure
1. Operate the excavator and rotate the upper
structure to the direction for convenience of
removal and diesel oil draining. Open the oil
drain valve (1) to drain the diesel oil in the tank;
Notice: Collect diesel oil with with
suitable barrel, and the capacity of 936E
reusable fuel tank is about 620L,and the
capacity of 930E reusable fuel tank is about
510L.
1

2. Remove two bottom plates (2) and (3) under

the fuel tank;
7-28
7.2 Power System December 30, 2017
7.2.5 Removal and Installation of the Fuel Tank Assembly CLG930E/936E

Figures Procedure
3. Disconnect three fuel pipes at the bottom of the
fuel tank: fuel drain pipe (4), fuel suction pipe
(5) and fuel return pipe (6).
Notice: After removal, the mouths of the
fuel pipes and the fuel port on the fuel tank
must be masked immediately to prevent dust
and other foreign matters from entering the
fuel system to cause engine damages.

4. Disconnect the harness (7) of the fuel level

sensor;

5. Remove the handrail (8) and the trim cover (9);

Notice: If a machine model is equipped
with a fuel filling system, first remove the fuel
refueling pump filler pipe assembled on the
fuel tank, and go to the next step.
 7-29
December 30, 2017 7.2 Power System
CLG930E/936E 7.2.5 Removal and Installation of the Fuel Tank Assembly

Figures Procedure
6. Remove the 6 mounting bolts (10) at the
bottom of fuel tank;

7. Check the connecting parts around the fuel

tank and make sure that they will impose no
influence on the lifting of the fuel tank.
Afterwards, lift the fuel tank via lifting rings
welded at the top and the sides of the fuel tank,
and put it in a safe place.

Installation

The installation sequence is just opposite to the removal sequence.

For the tightening torque of bolts, refer to the general tightening torque.
Refill the fuel, restore the assembly of the negative battery cable, operate the engine, check the line for
leakages and check whether the fuel level indication on the display is normal.
7-30
7.2 Power System December 30, 2017
7.2.6 Removal and Installation of the Injector CLG930E/936E

7.2.6 Removal and Installation of the Injector

Preparation steps

The area around injector shall be cleaned thoroughly.

Disconnect the fuel supply line of the high-pressure injector.
Disconnect fuel-return manifold;
Removal
Figures Procedure
1. Remove the packing clamp of the injector.

2. Remove the injector with injector puller (part

No. 3823276 or 3164706).

If some injectors need to be removed, do the

following:
Remove the injector with injector puller
Move injectors up and down.
 7-31
December 30, 2017 7.2 Power System
CLG930E/936E 7.2.6 Removal and Installation of the Injector

Installation

Figures Procedure
1. Lubricate the sleeve seal lip with anti-adhering
grease (part No.: 3824879). Assemble
injector, seal sleeve, new copper seal washer
and packing clamp.
Use just one copper washer.

anti--bonding
Maintenance skills
complex agent
Applying a thin layer of clean engine oil between
the washer and the injector can help to keep the
washer in position when installing.

2. Install injector assembly into the hole of the

injector. Return pipe joint of the injector must
be towards valve chamber cover.

3. Install and tighten the packing bolts.

Torque value: 28 n.m [21 ft-lb]
7-32
7.2 Power System December 30, 2017
7.2.7 Removal and Installation of the Engine Front Seal CLG930E/936E

Figures Procedure
4. Install the fuel return pipe.
5. Install the high-pressure fuel pipe.
Notice: Fuel pressure in the fuel pipeline is
enough to penetrate the skin and cause
serious personal injuries. Gloves and
protection clothes shall be worn.

7.2.7 Removal and Installation of the Engine Front Seal

Preparation steps

Disconnect the battery.

Remove the drive belt.
Remove the shock absorber.
Remove front gear chamber cover.

Removal

Figures Procedure

Overview
Crankshaft front oil seal is installed into front gear
chamber cover. Adopt two lays
TeflonTM seal. During assembly, sealing surface of
the crankshaft must be cleaned and there is no
engine oil in the surface.

Fix the gear chamber cover, and remove oil seal

from the gear chamber cover. Push the oil seal to
the front side of the cover from its rear side.
 7-33
December 30, 2017 7.2 Power System
CLG930E/936E 7.2.7 Removal and Installation of the Engine Front Seal

Installation

Figures Procedure
1. Plastic guide mounting tool will be remained in
the oil seal of the engine oil.
2. Oil seal will be placed on the oil seal
installer(part No.: 3824499) with the dust lip
outwards.
3. Before installation, Loctite 277 or equivalent is
painted for one layer on outside diameter of the
oil seal.

4. Correctly support the oil seal flange of the

engine oil for front cover, and prevent the oil
seal of the engine oil and front cover from
damaging.
5. Press the oil seal of the engine oil into the front
cover from the back of the front cover towards
the front.
6. Press the oil seal of the engine oil until the
maintenance tool tops against the front cover.

Last procedures
7. Install front gear chamber cover.
8. Install the shock absorber.
9. Install the drive belt.
10. Connect the battery.
11. Operate the engine, and check for leakages.
7-34
7.2 Power System December 30, 2017
7.2.8 Removal and Installation of the Engine Rear Seal CLG930E/936E

7.2.8 Removal and Installation of the Engine Rear Seal

Removal

Figures Procedure
1. Two 3-mm [0.12-in] holes at a 180-degree
angle are drilled via the metal from the outside
of rear crankshaft oil seal
Notice: When drilling, make sure don’t
damage the crankshaft.

2. Install No.10 metal plate screw into the sliding

weight (part No.: 3823822).
3. Install screw or sliding weight into rear oil seal
hole of the crankshaft.
4. Remove the oil seal.
 7-35
December 30, 2017 7.2 Power System
CLG930E/936E 7.2.8 Removal and Installation of the Engine Rear Seal

Installation

Figures Procedure
1. Install the oil seal replacement tool guide and
the oil seal on the crankshaft.

2. Push the oil seal on the guide and push it into

the flywheel housing hole.
3. Remove the guide.

Notice: Make sure that the oil seal is

completely installed into rear flywheel housing.
4. Install the oil seal into the correct depth using
the mounting tool in the oil seal replacement
tool.
In order to prevent the oil seal from being
damaged, knock alternately the mounting tool at
12 o'clock, 3 o'clock, 6 o'clock and 9 o'clock
7-36
7.2 Power System December 30, 2017
7.2.9 Removal and Installation of the Cylinder Head Assembly CLG930E/936E

7.2.9 Removal and Installation of the Cylinder Head Assembly

Removal

Figures Procedure
1. Remove the cylinder head screw in
the order as shown in the Figure.

Front

2. Use crane or hydraulic arm to remove

the cylinder head. Make sure that the
cylinder head moves in vertical
upward direction.
3. Remove the cylinder head gasket
from the cylinder block.
Notice: the component weight is
equal to or more than 23 kg [50 lb]. In
order to avoid personal injury, please
lift the component using the crane or
with the help of the other person.
Notice: Do not put the cylinder
head on the combustion surface.
Otherwise, the combustion surface
will be damaged.
 7-37
December 30, 2017 7.2 Power System
CLG930E/936E 7.2.9 Removal and Installation of the Cylinder Head Assembly

Installation
Figures Procedure

Notice: Make sure that the

cylinder head gasket is aligned with
the hole on the cylinder block. If not,
the engine will be damaged.
1. Put new cylinder head gasket on the
dowel pin.

Notice: The component weight is

equal to or more than 23 kg [50 lb]. In
order to reduce possibility of personal
injury, please lift the component using
the lifting equipment or with the help
of the other person.
2. Be careful to put the cylinder head on
the cylinder block, and seat it on the
dowel pin.

3. Lubricate other cylinder head screw

thread and lower part of the screw
head using oil.
4. Install and tighten the screws by
hand.
7-38
7.2 Power System December 30, 2017
7.2.9 Removal and Installation of the Cylinder Head Assembly CLG930E/936E

Figures Procedure

Notice: The step is only for new

cylinder block or new cylinder head
bolt.

5. Tighten all screws in the numbering

sequence.
Check again the torque for all screws in
the tightening sequence.
Torque value: 95 n.m [70 ft-lb]

Front

6. Only tighten 14 long screws (at

middle two rows) in the numbering
sequence.
7. Check again the torque for all 14 long
screws in the numbering sequence.
Torque value: 145 n.m [107 ft-lb]

Front
 7-39
December 30, 2017 7.2 Power System
CLG930E/936E 7.2.9 Removal and Installation of the Cylinder Head Assembly

Figures Procedure
8. Only tighten 6 short screws (at
exhaust side) in the numbering
sequence.
9. Check again the torque for all 6 short
screws in the numbering sequence.
Torque value: 105 n.m [77 ft-lb]

10. Only tighten 6 short screws (at intake

side) in the numbering sequence.
11. Check again the torque for all 6 short
screws in the numbering sequence.
Torque value: 95 n.m [70 ft-lb]

12. Check again the tightening torque of

all screws.
13. Check 14 long bolts in step 4 in the
numbering sequence.
14. Check 6 short bolts (at exhaust side)
in step 6 in the numbering sequence.
15. Check 6 short bolts (at intake side) in
step 8 in the numbering sequence.

Front
7-40
7.2 Power System December 30, 2017
7.2.9 Removal and Installation of the Cylinder Head Assembly CLG930E/936E

Figures Procedure
16. Rotate the bolts in step 2 by 90° as
shown on the bolt head in the
numbering sequence.

90°
 7-41
December 30, 2017 7.3 Track Travel System
CLG930E/936E 7.3.1 Removal and Installation of the Track Roller

7.3 Track Travel System

7.3.1 Removal and Installation of the Track Roller

Removal

Figures Procedure
1. Support the complete machine so that the
platform forms 90° angle with the track frame,
and support one side track beam.

2. Loosen the filling valve (1), discharge grease in

the tensioner, and reduce track tensioning
level.

Danger: Because the pressure of

the internal grease is high, the valve may
fly off, therefore, do not loosen the filling
valve 1 more than two circles.
7-42
7.3 Track Travel System December 30, 2017
7.3.1 Removal and Installation of the Track Roller CLG930E/936E

Figures Procedure
3. Remove the track roller mounting bolts.

Installation

The installation procedures are just opposite to the removals.

Adjust the track tension to the proper level, refer to the "Measurement and Adjustment of Track Tension"
in the Chapter of Test and Adjustment.
Apply TONSAN 1277 thread locker on track roller mounting bolt and the tightening torque of M18-10.9 is
600±35N.m.
 7-43
December 30, 2017 7.3 Track Travel System
CLG930E/936E 7.3.2 Removal and Installation of the Carrier Roller

7.3.2 Removal and Installation of the Carrier Roller

Removal

Figures Procedure
1. Loosen the filling valve (1), discharge grease in
the tensioner, and reduce track tensioning
level.

Danger: Because the pressure of

the internal grease is high, the valve may
fly off, therefore, do not loosen the filling
valve 2 more than two circles.

2. Support the track beside the carrier roller (2)

with a hydraulic jack (or wooden block) to the
height suitable for the removal of the carrier
roller.
7-44
7.3 Track Travel System December 30, 2017
7.3.2 Removal and Installation of the Carrier Roller CLG930E/936E

Figures Procedure
3. Loosen carrier roller mounting bolts with a
wrench, and remove the carrier roller. Take out
the carrier roller from the mounting hole.

Installation

Installation sequence is just reverse to the removal sequence.

Adjust the track tension to the proper level, refer to the "Measurement and Adjustment of Track Tension"
in the Chapter of Test and Adjustment.
Clean the thread hole before installing the bolt on the carrier roller, apply anaerobic thread locker
(TONSAN 1277), the tightening torque of M18-10.9 is 600 ± 35N.m.
 7-45
December 30, 2017 7.3 Track Travel System
CLG930E/936E 7.3.3 Removal and Installation of the Track Assembly

7.3.3 Removal and Installation of the Track Assembly

Removal

Figures Procedure
1. Move the complete machine forwards so that
the main pin (1) is located at the front section
of the sprocket.

2. Loosen the filling valve (2), discharge grease in

the tensioner, and reduce track tensioning
level.

2
Danger: Because the pressure of
the internal grease is high, the valve may
fly off, therefore, do not loosen the filling
valve 2 more than two circles.
7-46
7.3 Track Travel System December 30, 2017
7.3.3 Removal and Installation of the Track Assembly CLG930E/936E

Figures Procedure
3. Squeeze out the main pin with a pin squeezing
machine (3).

4. Move the complete machine forward to unfold

the track.

Installation

Installation steps:
Installation sequence is just reverse to the removal sequence.
★ Refer to the "Measurement and Adjustment of Track Tension" in the chapter of "Test and Adjustment"
to adjust the track tension properly.
 7-47
December 30, 2017 7.3 Track Travel System
CLG930E/936E 7.3.4 Removal and Installation of the Sprocket

7.3.4 Removal and Installation of the Sprocket

Removal

Figures Procedure
1. Refer to "Removal of Track Assembly" section
to remove the track assembly. Rotate the work
implement by 90°, and jack up the complete
machine with the work implement. Rotate the
track to the sprocket (1) side. Unfold the track.

2. Remove 26 sprocket mounting bolts, and

remove the sprocket.

Installation

The installation procedures are just opposite to the removals.

Apply the anaerobic thread locker (TONSAN 1277) to the sprocket mounting bolts and tightening torque
of M20-10.9 is 600±55N.m.
7-48
7.3 Track Travel System December 30, 2017
7.3.5 Removal and Installation of the Idler Assembly and Tensioner Assembly CLG930E/936E

7.3.5 Removal and Installation of the Idler Assembly and Tensioner

Assembly

Removal

Figures Procedure
1. Refer to "Removal of Track Assembly" section
to remove the track assembly.

2. Push out the idler and tensioner (1) out of the

idler bracket with a crowbar;
 7-49
December 30, 2017 7.3 Track Travel System
CLG930E/936E 7.3.5 Removal and Installation of the Idler Assembly and Tensioner Assembly

Figures Procedure
3. Lift up the idler and tensioner assembly (1) and
move it forwards for removal.

4. Remove the tensioner from the idler assembly.

Installation

Installation sequence is just reverse to the removal sequence.

Apply the anaerobic thread locker (TONSAN 1277) to the tensioner and idler assembly connecting bolt
and the tightening torque of M16-10.9 is 305±25N.m.
7-50
7.3 Track Travel System December 30, 2017
7.3.6 Removal and Installation of the Revolving Frame CLG930E/936E

7.3.6 Removal and Installation of the Revolving Frame

Removal

Figures Procedure
1. Remove the work implement assembly. For
details, see the Removal and Installation of
Work Implement Assembly
2. Remove the counterweight assembly. For
details, see the Removal and Installation of
Counterweight Assembly
3. Disconnect hoses (1)-(4).
Label the disconnected hoses to prevent mistakes
during reinstallation.
4. Lift the boom cylinder assembly (5) temporarily.

5. Remove the plate (6) and the pin shaft (7), and
then remove the boom cylinder assembly (5).
6. Remove the opposite boom cylinder assembly
in the same steps.
 7-51
December 30, 2017 7.3 Track Travel System
CLG930E/936E 7.3.6 Removal and Installation of the Revolving Frame

Figures Procedure
7. Remove bolts (8) from the center joint.
8. Disconnect hoses (9) (10) and tubes (11) (14).
9. Label the disconnected hoses and tubes to
prevent mistakes during reinstallation.
10. Lift the platform as temporarily.
11. Remove 40 mounting bolts and remove the
revolving frame assembly.

Installation

The installation procedures are just opposite to the removals.

Apply the anaerobic thread locker (TONSAN 1277) to the swing bearing mounting bolt and the tightening
torque of M24-10.9 is 1020±90N.m.
7-52
7.3 Track Travel System December 30, 2017
7.3.7 Removal and Installation of the Swing Bearing CLG930E/936E

7.3.7 Removal and Installation of the Swing Bearing

Removal

Figures Procedure
1. Remove the revolving frame assembly. For
details, see the Removal of Revolving Frame
2. Remove the 40 mounting bolts (1) for removing
the swing bearing.

3. Lift the swing bearing (2).

Swing bearing weight:
1. 930E: 445kg
2. 936E: 504kg
 7-53
December 30, 2017 7.3 Track Travel System
CLG930E/936E 7.3.7 Removal and Installation of the Swing Bearing

Installation

Figures Procedure

Soft part of inner race

Soft part of outer race The installation procedures are just opposite to the
removals.
The front of the machine

Apply the anaerobic thread locker (TONSAN 1277)

to the swing bearing mounting bolt and the
tightening torque of M24-10.9 is 1020±90N.m.
When installing the swing bearing, the tape mark S
on the swing bearing inner ring needs to face the
right side
7-54
7.4 Covering Parts December 30, 2017
7.4.1 Removal and Installation of the Engine Hood CLG930E/936E

7.4 Covering Parts

7.4.1 Removal and Installation of the Engine Hood

Removal

If the engine is in the high-temperature state when the machine works, remove the engine hoods
after the engine cools down.

Be careful not to damage rubber seal strip and sponge during the removal of engine hood.

Figures Procedure
1. Lower and shut down the work implement;
2. Open the engine hood;

3. Remove the pin (2) connecting the engine

hood and the mast with pliers;
 7-55
December 30, 2017 7.4 Covering Parts
CLG930E/936E 7.4.1 Removal and Installation of the Engine Hood

Figures Procedure
4. After laying the engine hood flat, remove 4
bolts (3) mounting the engine hood.

5. Lift down the engine hood, and put it on flat

ground covered by foam cardboard.

Installation

The installation sequence is just opposite to the removal sequence.

The tightening torque of engine hood mounting bolts M12: 120±10Nm.
7-56
7.4 Covering Parts December 30, 2017
7.4.2 Removal and Installation of the Counterweight CLG930E/936E

7.4.2 Removal and Installation of the Counterweight

Removal

Before the removal of the counterweight, move the machine to the level ground to make sure no
heavy sways when lifting the counterweight in order to avoid of personal injury.

Figures Procedure
1. Remove the engine hood and rearview
instrument circuit.

2. Stably lift the counterweight with a steel wire

rope and a hoisting equipment to prevent it
from falling down during removal.
 7-57
December 30, 2017 7.4 Covering Parts
CLG930E/936E 7.4.2 Removal and Installation of the Counterweight

Figures Procedure
3. Remove the 4 counterweight mounting bolts
M42(1) and washers with a torque wrench.

4. Lift up and move away the counterweight, and

put it on a flat and safe location.
Notice: Do not knock the counterweight
against the engine or radiator.
CLG930E counterweight weight 5500kg,
CLG936E counterweight weight 6500kg.

Installation

The installation sequence is just opposite to the removal sequence.

Counterweight mounting bolt M42: 4; tightening torque: 4600±150Nm, and apply anaerobic thread
locker (TONSAN 1277) on the bolt thread.
Install and adjust the counterweight:
1. Adjust the level or clearance differences between the counterweight and the revolving frame and the
covering part with shims.
2. Fix the counterweight so that the longitudinal clearance between the counterweight and the revolving
frame and the door, and the clearance is in the range of 15±3mm.
3. The clearance between the outer profile plan area of the door and the outer profile plan area of the
counterweight in the transverse direction of the complete machine is within the range of 5±3 mm;
4. The outer profile of the revolving frame is aligned with the outer profile of the counterweight;
7-58
7.5 Hydraulic System December 30, 2017
7.5.1 Removal and Installation of Center Joint CLG930E/936E

7.5 Hydraulic System

7.5.1 Removal and Installation of Center Joint

Removal

Before removing hydraulic lines, lower the work implement to the ground completely, shut down
the engine, turn the key to the KEYON position, operate all hydraulic control levers several times
to release the residual pressure from the hydraulic system,and then press the exhaust button of
hydraulic oil tank breather valve to release the internal pressure from the oil tank.

Before removing the lines, fittings or hoses, make the marks so as to prevent wrong installation
while restoring. Clean the periphery of the assembled oil port as required, and put a drip pan to
receive oil.
Seal the lines, fittings or hoses with plugs or caps when they are in disassembling state, so as to
prevent pollution source from entering the hydraulic system.

Figures Procedure
1. Remove the bottom plate (1);
 7-59
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.1 Removal and Installation of Center Joint

Figures Procedure
2. Remove the 4 travel pipes (2);
3. Remove 2 oil return pipes (3);
4. Remove the 2 pilot pipes (4);

5. Remove the 4 travel pipes (5);

6. Remove the oil return pipe (6);
7. Remove the pilot pipe (7);

8. Remove the locating bolt (8) from the center

joint;
9. Remove the 4 captive bolts (9) from the center
joint.
7-60
7.5 Hydraulic System December 30, 2017
7.5.1 Removal and Installation of Center Joint CLG930E/936E

Figures Procedure
10. Move the center joint out with the lifting slings
and the hoisting equipment. Lifting weight:
about 57kg.

Installation

The installation sequence is just opposite to the removal sequence.

Tightening torque of center joint mounting bolts M16-10.9: (305±25) Nm
Tightening torque of angle-sealed joint with O -ring: G3/8: (75±5) N.m; G3/4: (165±15) N.m
Tightening torque for 24° cone seal hose joint with O-ring: M18×1.5: (37±2) N.m; M22×1.5: (47±2) N.m;
M30×1.5: (116±5 ) N.m;
 7-61
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.2 Disassembly and Assembly of the Center Joint

7.5.2 Disassembly and Assembly of the Center Joint

Disassembly

Choose a clean location. Lay rubber plates or cloth, etc. for removal, and be careful not to
damage parts.

Figures Procedure
1. Remove the four bolts (1) and washers (2).
Notice: Be careful to fix the center joint to
prevent hard objects from scratching the
sealing surface of each oil port.

2. Remove the end cover (3).

Notice: Be careful not to damage the inner
O-ring while taking out the end cover.
7-62
7.5 Hydraulic System December 30, 2017
7.5.2 Disassembly and Assembly of the Center Joint CLG930E/936E

Figures Procedure
3. Remove the sealing end cover O-ring (4)
Notice: Be careful not to damage the O-
ring.

4. Remove the snap ring (5) from the spindle (6).

Notice: be careful in operation and not to
damage the mounting face.

5. Remove the stop ring (7).

 7-63
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.2 Disassembly and Assembly of the Center Joint

Figures Procedure
6. Extract the spindle (6) out of the center joint
body (8) with a puller.
7. Remove the bushing (9) .
Notice: Hook the claw end of the puller to
the flange face, and push the spindle out of the
end cover.
Notice: While taking out the bushing, be
careful not to damage the sealing surface of
the spindle.

8. Remove the seal rings (12) (14) dust ring (10)

and the upper center joint body.
Notice: Be careful not to damage the
sealing surface of the joint body.
Notice: When the seal rings cannot be
taken out, the seal rings can be taken out by
destroying, and replace them with new seal
rings during re-installation.

9. Remove the four plugs (11) at the end of the

spindle (6).
Notice: be careful not to damage the O-
ring (13).
7-64
7.5 Hydraulic System December 30, 2017
7.5.2 Disassembly and Assembly of the Center Joint CLG930E/936E

Assembly

The assembly sequence is just opposite to the removal sequence. Pay attention to the assembly of the
following items.
1. Repair the damaged section during removal, and prepare replaceable parts in advance.
2. Thoroughly clean each part with cleaning oil, and dry with compressed air.
3. The clean working oil must be applied to the spindle section and the center joint body before
assembly.
4. O-ring, oil seal and other seals shall be replaced in principle.
5. Prepare torque wrenches used for mounting bolts and oil plugs at each section, and tighten them
with the torques specified in the table below.

Name Specifications Tightening torque

Bolt M10×25-8.8-Zn.D 52±6N·m
Plug G1/2 110±10N·m
 7-65
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.3 Removal and Installation of Hydraulic Oil Tank

7.5.3 Removal and Installation of Hydraulic Oil Tank

Removal

Before removing hydraulic lines, lower the work implement to the ground completely, shut
down the engine, turn the key to the KEYON position, operate all hydraulic control levers
several times to release the residual pressure from the hydraulic system,and then press the
exhaust button of hydraulic oil tank breather valve to release the internal pressure from the oil
tank.

Before removing the lines, fittings or hoses, make the marks so as to prevent wrong installation
while restoring. Clean the periphery of the assembled oil port as required, and put a drip pan to
receive oil.
Seal the lines, fittings or hoses with plugs or caps when they are in disassembling state, so as
to prevent pollution source from entering the hydraulic system.

Figures Procedure
1. Rotate the revolving frame, and evacuate a
removal and installation space for fuel tank
bottom plate.
7-66
7.5 Hydraulic System December 30, 2017
7.5.3 Removal and Installation of Hydraulic Oil Tank CLG930E/936E

Figures Procedure
2. Remove the fuel tank bottom plates (1).

3. Put the bucket under the oil drain port of the

tank.
4. Remove the drain plug (2), drain the oil
completely, and then reinstall the drain plug
back;

5. Remove the dipstick (3);

6. Remove the pilot valve group (4);
 7-67
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.3 Removal and Installation of Hydraulic Oil Tank

Figures Procedure
7. Remove the oil return pipe (5);
8. Remove the pump oil return pipe (6).

9. Remove the front cover plate (7).

10. Disconnect the oil return pipe (8);

11. Remove the solenoid valve group(19).
12. Disconnect the 6 oil return hoses (10).
13. Disconnect the hose clamp (11).
7-68
7.5 Hydraulic System December 30, 2017
7.5.3 Removal and Installation of Hydraulic Oil Tank CLG930E/936E

Figures Procedure
14. Remove 5 oil suction tube flange mounting
bolts (12), and remove 6 fuel tank mounting
captive bolts (13).

15. Penetrate through the lifting eyes, and lift and

move the fuel tank to a clean and safe place
with a sling and hoisting equipment. Lifting
weight: 250kg.

Installation

The installation sequence is just opposite to the removal sequence.

The tightening torque of the mounting bolts: M16-10.9 : 305±25Nm.
The threads of mounting bolts shall be coated with thread locker (Tonsan 1277) before installation.
Refill hydraulic oil.
 7-69
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.4 Removal and Installation of Main Control Valve Assembly

7.5.4 Removal and Installation of Main Control Valve Assembly

Removal

Before removing hydraulic lines, lower the work implement to the ground completely, shut down
the engine, turn the key to the KEYON position, operate all hydraulic control levers several times
to release the residual pressure from the hydraulic system,and then press the exhaust button of
hydraulic oil tank breather valve to release the internal pressure from the oil tank.

Before removing the lines, fittings or hoses, make the marks so as to prevent wrong installation
while restoring. Clean the periphery of the assembled oil port as required, and put a drip pan to
receive oil.
Seal the lines, fittings or hoses with plugs or caps when they are in disassembling state, so as to
prevent pollution source from entering the hydraulic system.

Figures Procedure
1. Rotate the revolving frame, and evacuate a
removal and installation space for fuel tank
bottom plate.
7-70
7.5 Hydraulic System December 30, 2017
7.5.4 Removal and Installation of Main Control Valve Assembly CLG930E/936E

Figures Procedure
2. Remove the fuel tank bottom plates (1).

3. Place a barrel below the oil drain port of the

tank, remove the drain plug (2) and drain the oil
completely, and then reinstall the drain plug
back.

4. Remove the front cover plate (3).

 7-71
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.4 Removal and Installation of Main Control Valve Assembly

Figures Procedure
5. Remove the bottom plate (4) under the main
control valve.

6. Disconnect the intake pipe (5).

7. Disconnect the oil return pipe (6).
8. Disconnect the swing motor return pipe (7).
9. Disconnect pilot hose (8).
10. Disconnect the working port hose (9).

11. Remove 3 captive bolts (10) of the main control

valve.
7-72
7.5 Hydraulic System December 30, 2017
7.5.4 Removal and Installation of Main Control Valve Assembly CLG930E/936E

Figures Procedure
12. Shift the main control valve out with lift
equipment such as a sling. Lifting weight:
about 231kg.

Installation

The installation sequence is just opposite to the removal sequence.

Tighten the mounting bolts (M12-10.9) of the main control valve assembly to 120 ± 10Nm.
Tightening torque of the pilot hose: M18×1.5: 37±2N.m
 7-73
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.5 Disassembly and Assembly of the Main Control Valve

7.5.5 Disassembly and Assembly of the Main Control Valve

Related drawings

Please refer to the structure drawing relating to the introduction of the main control valve in the
section "Structural Function and Service". The numbers involved below are subject to the part
numbers in the structure drawing.

1. As hydraulic elements are precisely machined parts, select an especially clean place to carry
out the removal and installation.

2. In addition to such handling of the control valve, be careful enough not to let dust and sand
intrude inside.

3. When removing the control valve from the base machine, seal every interface with a cover.
Before removal, confirm again such covers are completely installed, and thoroughly clean the
outside of the whole component as. Operation should be performed on an appropriate operation
platform, on which should be covered with clean paper sheets or rubber plates before starting
operation.

4. The force support in carrying and moving the control valve should be acted on the solid
positions of the body and should never be acted on the projecting positions such as the spool
and spring cover. Be careful in the operation.

5. Although various tests (such as the overflow properties test, internal leakage test and
passage loss test) can be carried out after the removal and assembly of elements, these must be
carried out on a hydraulic test device. Do not perform removal in a place where test adjustments
can’t be done due to restrictions, even though the removal is available based on the structure.
Prepare clean cleaning oil, working oil and grease, etc, in advance.

Disassembly

The numbers in the bracket ( ) behind the part name represent the part number in the structure
drawing.
7-74
7.5 Hydraulic System December 30, 2017
7.5.5 Disassembly and Assembly of the Main Control Valve CLG930E/936E

Figures Procedure
1. Place the control valve on an operation
platform.
Notice: Conduct removal at cleaning site
and do not break the flange face.
 7-75
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.5 Disassembly and Assembly of the Main Control Valve

Figures Procedure
2. The removal of the main spool: the travel
(301), bucket (304), rotation (305), optional
(309), arm 2 (306), boom 2 (307) and rotation
priority (311).
a. Loosen the hexagon socket bolt (273), and
remove the spring cover (201 or 202) and O-
ring (261).
b. Remove the spool, spring, spring holder
(332), stopper (335 or 339) and bolt with
liners (336) from inside the valve body in the
spool group state.
Notice: Do not break the valve body when
take the valve body out of the spool group.

c. Use a bench vice containing a shield over

the jaw to sandwich a protection plate (such
as an aluminum plate) between the bench
vice and the spool so that the spool is fixed.
Remove the bolt with liners (336) from the
spool group, and disassemble the spring,
stop (335 or 339) and spring holder (332).
7-76
7.5 Hydraulic System December 30, 2017
7.5.5 Disassembly and Assembly of the Main Control Valve CLG930E/936E

Figures Procedure
3. Removal of the boom 1 spool (303):
a. Loosen the hexagon socket bolt (273), and
remove the spring cover (201) and O-ring
(261).
b. Remove the boom 1 spool (303), springs
(320 and 328), spring holder (332), stopper
(335) and bolt with liners (336) from inside
the valve body A (101) in the spool group
state.
Notice: When removing the spool group
from the valve body A (101), be careful not to
damage the valve body.
c. Use a bench vice containing a shield over
the jaw to sandwich a protection plate (such
as an aluminum plate) between the bench
vice and the spool so that the boom 1 spool
(303) is fixed. Remove the bolt with liners
(336) from the spool group, and disassemble
the spring (320 and 328), stopper (335) and
spring holder (332).
d. After the removal of 3 items above, do not
perform further removal of the boom 1 spool
(303).
 7-77
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.5 Disassembly and Assembly of the Main Control Valve

Figures Procedure
4. Removal of arm 1 spool (302):
a. Loosen the hexagon socket bolt (273), and
remove the spring cover (201) and O-ring
(261).
b. Remove the arm 1 spool (302), springs (320
and 328), spring holder (332), stopper (335)
and bolt with liners (336) from inside the
valve body B (102) in the spool group state.
Notice: When removing the spool group
from the valve body B (102), be careful not to
damage the valve body.
c. Use a bench vice containing a shield over
the jaw to sandwich a protection plate (such
as an aluminum plate) between the bench
vice and the spool so that the arm 1 spool
(302) is fixed. Remove the bolt with liners
(336) from the spool group, and disassemble
the spring (320 and 328), stopper (335) and
spring holder (332).
d. After the removal of 3 items above, do not
perform further removal of the arm 1 spool
(302).
7-78
7.5 Hydraulic System December 30, 2017
7.5.5 Disassembly and Assembly of the Main Control Valve CLG930E/936E

Figures Procedure
5. Removal of straight travel spool (308):
a. Loosen the hexagon socket bolt (273), and
remove the spring cover (201) and O-ring
(261).
b. Remove the straight travel spool (308),
springs (322 and 323), spring holder (332),
stopper (335) and bolt with liners (336) from
inside the valve body A (101) in the spool
group state.
Notice: When removing the spool group
from the valve body A (101), be careful not to
damage the valve body.
c. Use a bench vice containing a shield over
the jaw to sandwich a protection plate (such
as an aluminum plate) between the bench
vice and the spool so that the straight travel
spool (308) is fixed. Remove the bolt with
liners (336) from the spool group, and
disassemble the spring (322 and 323),
stopper (335) and spring holder (332).
d. After the removal of ? items above, do not
perform further removal of the straight travel
spool (308).
6. Removal of bypass stop valve (310):
a. Loosen the hexagon socket bolt (273), and
remove the spring cover (203) and O-ring
(262).
b. Remove the bypass stop spool (310),
springs (372 and 373), spring holder (331),
stopper (337) and bolt with liners (333) from
inside the valve body B (102) in the spool
group state.
Notice: When removing the spool group
from the valve body B (102), be careful not to
damage the valve body.
c. Use a bench vice containing a shield over
the jaw to sandwich a protection plate (such
as an aluminum plate) between the bench
vice and the spool so that the bypass stop
spool (310) is fixed. Remove the bolt with
liners (333) from the spool group, and
disassemble the spring (372 or 373), stopper
(337) and spring holder (331).
 7-79
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.5 Disassembly and Assembly of the Main Control Valve

Figures Procedure
7. Removal of spring covers (204, 205, 206):
Loosen the hexagon socket bolt (273), and remove
the spring covers (204, 205, 206) and O-ring (264).
When removing the bucket spool cover (206), first
loosen the plug (258) before removing the spool
cover from the valve body B (102). Remove the
plunger (211) after removing the spool cover.
7-80
7.5 Hydraulic System December 30, 2017
7.5.5 Disassembly and Assembly of the Main Control Valve CLG930E/936E

Figures Procedure
8. Removal of main relief valve (601) and
interface relief valves (602, 604):
Remove the main relief valve (601) and interface
relief valves (602, 604) from valve body.
Main relief valve (601)
Interface relief valve (602)
Interface relief valve (604)
After the relief valves are removed from the valve
bodies, do not perform further removal of the relief
valves.
 7-81
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.5 Disassembly and Assembly of the Main Control Valve

Figures Procedure
9. Removal of lock valve selector pair (252):
Loosen the hexagon socket bolt (252-171), and
remove the lock valve selector pair (252) and O-
ring (252-161).
After the lock valve selector pair (252) is removed
from the valve body, do not perform further
removal of the lock valve selector pair.

10. Removal of negative control relief valve (610):

Remove the negative control valve (610) from the
valve body.
After the negative control valve (610) is removed
from the valve body, do not perform further
removal.
7-82
7.5 Hydraulic System December 30, 2017
7.5.5 Disassembly and Assembly of the Main Control Valve CLG930E/936E

Figures Procedure
11. Removal of arm regeneration stop valve (257):
Remove the bushing (257-253), spring (257-231),
spring holder (257-232), spool (257-211) and valve
bushing(257-212) from the valve body B (102).
 7-83
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.5 Disassembly and Assembly of the Main Control Valve

Figures Procedure
12. Removal of logic control valve (251), rotary
logic valve group (254) and arm 2 logic valve
group (256):
a. Loosen the hexagon socket bolt (251-120),
and remove the logic control valve (251) and
O-rings (251-112.-113).
b. Remove the rotary logic valve group (254)
and arm 2 logic valve group (256) from the
valve body.
c. After the logic control valve is removed from
the valve body and the logic valve groups
are removed, do not perform further
removal.
7-84
7.5 Hydraulic System December 30, 2017
7.5.5 Disassembly and Assembly of the Main Control Valve CLG930E/936E

Figures Procedure
13. Removal of check valve:
a. CP1, C2, CCb, LCb, LCo, LCk, LCa, LCAT2

b. CMR1, CMR2
Remove the plug (553), and then remove the cone
valve (512) and spring (521).

c. CRa, CRb
Remove the plug (552), and then remove the cone
valve (513) and spring (523).
d. CCk, CCo
Remove the plug (551), and then remove the cone
valve (514) and spring (521).
e. Remove the plug (550), and then remove
the steel ball (541), spring (543) and spring
holder (542).
 7-85
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.5 Disassembly and Assembly of the Main Control Valve

Figures Procedure
14. Removal of flange (209):
Loosen the hexagon socket bolt (971), and remove
the flange (209) and O-ring (165).
15. Removal of the plate (210):
Loosen the hexagon socket bolt (274), and remove
the plate (210) and O-ring (165).
16. Removal of the orifice plug for signal oil circuit:
Except special circumstances, do not generally
remove the plug (151) and orifice plug (156).

17. Removal of the valve body:

a. Except special circumstances, do not
generally remove the anchor bolt of the
valve body B (102).
b. As the plugs unrecorded in the above
procedures are used for technological holes
and valve body sanitary holes, do not
remove them except special circumstances.
7-86
7.5 Hydraulic System December 30, 2017
7.5.5 Disassembly and Assembly of the Main Control Valve CLG930E/936E

Post-removal inspection 3. Make sure the main valve spool outer

circumferential surface and valve seat inner
Thoroughly clean all the removed parts with circumferential surface have no drag marks
clean mineral oil, and inspect them after they are and galling.
dried by compressed air. Place all parts on clean
paper or cloth. 4. Make sure the springs have no breaks,
deformations or abrasion.
Inspection of control valve
5. Make sure the damping holes of the spool
1. Inspect the entire surface of each part. No and valve seat of the main valve are not
burrs, rough edges, drag marks, galling, blocked by impurities.
scratches or other defects are allowed.
6. Replace all O-rings with new ones.
2. Confirm that the seal groove faces of the
valve body and valve block are smooth. 7. When minor damage is found in the above
Defects such as impurities, deformations, pits inspection, it can be eliminated in the
and corrosion are not allowed. abrading method.

3. If there are deformations and pits on the 8. When a defective part exists, replace the
valve seat surface of the check valve body relief valve by group.
and valve block, eliminate them in the
Assembly
abrading method.
The number in the () after a part name
represents a symbol in the structure drawing.
Precautions in assembling O-ring seals
Do not keep abrasive paste remaining in the
valve body and valve block. 1. Note that the seals must have neither
forming defects nor the scars generated in
4. Confirm that sliding and mating parts are able use.
to flexibly rotate by hand and no impurities
2. Apply grease or working oil in the positions of
are left in all grooves and passages.
the seals and similarly shaped seals to
5. Replace the spring with a new one in case of ensure sufficient lubrication.
a break or deformation.
3. Do not stretch the seals to a permanent
6. When the relief valve acts ineffectively, repair deformation that they cannot recover.
it according to the removal and assembly of
4. When installing an O-ring, do not install it in a
the relief valve.
distorted way. A distorted O-ring is difficult to
7. Replace all seals and O-rings with new ones. naturally recover after being installed, which
is the cause of oil leakage.
Inspection of relief valve
5. For the mounting bolts of all parts, fix them
1. Make sure the spool and valve seat head with a tool such as a torque wrench
seal surface of each valve have no defects according to the mounting torque as shown
and the mating surfaces are in uniform in Maintenance Criteria.
contact.
1. Install the check valve:
2. Make sure the spool and valve seat of the
main valve are easily and freely slid by hand. 1. Install the cone valves (511, 512, 513, 514)
and springs (521, 522, 523).
Install O-ring (561) in the plug (551, 552), and
fasten it in specified torque.
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December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.5 Disassembly and Assembly of the Main Control Valve

The following is the assembly of combination of 2. Install the O-ring (251-112.-113) on the valve
cone valve, spring and plug used. body (251-101) of logic control valve, fasten
it in specified torque with hexagon socket
bolt(251-120) and the mounting torque is 49-
Cone Installatio 65N·m.
Spring Plug
valve n site
511 521 551 8 places 5. Install the logic control valve (251) and
512 522 553 2 places arm 2 logic valve group (256):
513 523 552 2 places
1. Install arm 2 logic valve group (256) on the
514 521 551 2 places
valve body A (101).
2. Install the O-ring (251-112.-113) on the valve
Inner body (251-101) of logic control valve, fasten
Plug Mounting torque it in specified torque with hexagon socket
hexagon
No. (Nm) bolt(251-120) and the mounting torque is 49-
spanner
65N·m.
(551) 12mm 230~260
(552) 12mm 230~260 6. Install negative control relief valve (610):
(553) 10mm 130~150
Install the negative control relief valve (610) in
2. Install the steel ball (541), spring holder (542) the valve body, fasten it in the specified torque
and spring (543): shown in the following, and the mounting torque
is 69-78N·m.
Install an O-ring (166) on the plug (550), fasten it
in specified torque, and the mounting torque is
7. Install arm regeneration stop valve (257):
25-29N·m.
Install the valve bushing (257-212), spool (257-
2. Install the plate (210):
211), spring holder (257-232), and spring (257-
231) on the valve body B (102). Install the O-ring
Install the O-ring (165) on valve body B (102),
(257-265) on the bushing (257-253), fasten it in
fasten the hexagon socket bolt (274) in the
specified torque, and the mounting torque is 69-
specified torque, and the mounting torque is 98-
78N·m.
120N·m.
When the orientation of the plate is downward, 8. Install lock valve selector pair (252):
exchange the orientation of the control valve.
Install the O-ring (252-161) on the lock valve
3. Install the flange (209): selector pair (252), fasten it in specified torque
with hexagon socket bolt (252-171), and the
Install an O-ring (165) on the flange (209), fasten mounting torque is 10-14N·m.
the hexagon socket bolt (971) in the specified
torque, and the mounting torque is 49-65N·m.

4. Install logic control valve (251) and rotary

logic valve group (254):

1. Install the rotary logic valve group (254) on

the valve body B (102).
7-88
7.5 Hydraulic System December 30, 2017
7.5.5 Disassembly and Assembly of the Main Control Valve CLG930E/936E

9. Install main relief valve (601) and port 2. Upon completing the assembly of item 1,
relief valve (602, 604); install the spool group onto the valve body A
(101).
Install the main relief valve (601) and interface
relief valve (602, 604) onto the valve body, and
fasten it in the following specified torque.

Mounting While installing spool group on valve body A

Tool(s) (101), do it slowly and prudently.
torque
Main relief Never push the spool into the valve body
Wrench 32mm 69~79N·m
valve (601) forcibly.
Interface
Wrench 32mm or
relief valve 69~79N·m 11. Installation of the boom 1 spool (303):
Socket wrench 32mm
(602)
Interface
Wrench 36mm or
1. Use the bench vice provided with shield on
relief valve 120~140N·m the vice jaw, sandwich guard plate (aluminum
Socket wrench 36mm
(604) plate, etc.) between the bench vice and , and
fasten the intermediate part of the boom 1
10. Installation of the straight travel spool spool (303). Install the spring holder (332),
(308): spring (320, 328), and stopper (335), fasten
the bolt with liner (336) in specified torque,
1. Use the bench vice provided with shield on and the mounting torque is 16-18N·m.
the vice jaw, sandwich guard plate (aluminum
plate, etc.) between the bench vice and
spool, and fasten the intermediate part of the
straight travel spool (308). Install the spring
holder (332), spring (322, 323), and stopper Before installing the bolt with liner (336),
(335), fasten the bolt with liner (336) in apply #262 thread seal on it.
specified torque, and the mounting torque is The boom 1 spool (303) will deform if it is
16-18N·m. sandwiched improperly, so do not clamp
bench vice tightly.

2. Upon completing the assembly of item 1,

install the spool group onto the valve body A
Before installing the bolt with liner (336), (101).
apply #262 thread seal on it.

The straight travel spool (308) will deform if it

is sandwiched improperly, so do not clip the
bench vice too tightly. While installing spool group on valve body A
(101), do it slowly and prudently.
Never push the spool into the valve body
forcibly.
 7-89
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.5 Disassembly and Assembly of the Main Control Valve

12. Installation of the arm 1 spool (302): 1. Use the bench vice provided with shield on
the vice jaw, sandwich guard plate (aluminum
1. Use the bench vice provided with shield on plate, etc.) between the bench vice and
the vice jaw, sandwich guard plate (aluminum spool, and fasten the intermediate part of
plate, etc.) between the bench vice and each spool. Install the spring holder (332),
spool, and fasten the intermediate part of the spring, and stopper (335 or 339), fasten the
arm 1 spool (302). Install the spring holder bolt with liner (336) in specified torque, and
(332), spring (320, 328), and stopper (335), the mounting torque is 16-18N·m.
fasten the bolt with liner (336) in specified
torque, and the mounting torque is 16-
18N·m.
Before installing the bolt with liner (336),
apply #262 thread seal on it.
The spool will deform if it is sandwiched
Before installing the bolt with liner (336),
improperly, so do not clamp bench vice
apply #262 thread seal on it.
tightly.
The arm 1 spool (302) will deform if it is
sandwiched improperly, so do not clamp 2. Upon completing the assembly of item 1,
bench vice tightly. install the spool group into the valve body A
(101) and valve body B (102).
2. Upon completing the assembly of item 1,
then install the spool group onto the valve B
(102).
When installing the spool group on the valve
body A (101) and valve B (102), do it slowly
and prudently.
While installing the spool group onto the
Never push the spool into the valve body
valve body B (102), do it slowly and
forcibly.
prudently.
Never push the spool into the valve body 14. Installation of the bypass stop spool
forcibly. (310):

13. Installation of main spool: 1. Use the bench vice provided with shield on
the vice jaw, sandwich guard plate (aluminum
Travel (301), bucket (304), swing (305), backup plate, etc.) between the bench vice and , and
(309), arm 2 (306), arm 2 (307) and swing priority fasten the intermediate part of bypass stop
(311). spool (310). Install the spring holder (331),
spring (372, 373), and stopper (337), fasten
the bolt with liner (333) in specified torque,
and the mounting torque is 16-18N·m.
7-90
7.5 Hydraulic System December 30, 2017
7.5.5 Disassembly and Assembly of the Main Control Valve CLG930E/936E

3. Install spring cover (201, 202 & 203) on the

spool spring group, fasten it in the specified
torque with hexagon socket bolt (273), and
the mounting torque is 25-34N·m.
Before installing the bolt with liner (333),
apply #262 thread seal on it.
The bypass stop spool (310) will deform if it
Make sure that the spring cover (201.202.203)
is sandwiched improperly, so that protect the
has been provided with O-ring (261).
valve body from being clamped too tightly
with bench vice.

2. Upon completing the assembly of item 1,

then install the spool group onto the valve B
(102).

While installing the spool group onto the

valve body B (102), do it slowly and
prudently.
Never push the spool into the valve forcibly.

15. Installation of cover:

1. Install the spool cover (204, 205 & 206)) on

the side opposite to spring group of the
spool, fasten the hexagon socket bolt (273)
in specified torque, and the mounting torque
is 25-34N·m.

Make sure that the O-ring (264) has been

installed on the spool cover (204, 205, 206).

2. Installation of the bucket spool cover (206):

Install the plunger (211) in the bucket spool cover
(206). Install O-ring (561) on the plug (258), and
fasten it in specified torque. After fastening it,
install the bucket spool cover (206) in the same
way as that of item (1), and the mounting torque
is 150-180N·m.
 7-91
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.6 Removal and Installation of Main Pump Assembly

7.5.6 Removal and Installation of Main Pump Assembly

Removal

Before removing hydraulic lines, lower the work implement to the ground completely, shut down
the engine, turn the key to the KEYON position, operate all hydraulic control levers several times
to release the residual pressure from the hydraulic system,and then press the exhaust button of
hydraulic oil tank breather valve to release the internal pressure from the oil tank.

Before removing the lines, fittings or hoses, make the marks so as to prevent wrong installation
while restoring. Clean the periphery of the assembled oil port as required, and put a drip pan to
receive oil.
Seal the lines, fittings or hoses with plugs or caps when they are in disassembling state, so as to
prevent pollution source from entering the hydraulic system.

Figures Procedure
1. Rotate the revolving frame, and evacuate a
removal and installation space for fuel tank
bottom plate.
7-92
7.5 Hydraulic System December 30, 2017
7.5.6 Removal and Installation of Main Pump Assembly CLG930E/936E

Figures Procedure
2. Remove the fuel tank bottom plates (1).

3. Place a barrel below the oil drain port of the

tank, remove the drain plug (2) and drain the oil
completely, and then reinstall the drain plug
back.

4. Remove the angle block(3);

 7-93
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.6 Removal and Installation of Main Pump Assembly

Figures Procedure
5. Remove the angle block (4), angle block (5)
and angle block (6). Remove the oil filter
bracket (7).

6. Disconnect the main pump drain pipe (8).

7. Disconnect four pilot hoses (9).
8. Disconnect the pilot pump suction pipe (10).
9. Disconnect the two high-pressure oil pipes
(11).

10. Remove suction tube (12).

7-94
7.5 Hydraulic System December 30, 2017
7.5.6 Removal and Installation of Main Pump Assembly CLG930E/936E

Figures Procedure
11. Lift up the main pump with sling and hoisting
equipment, and remove 12 bolts of the
mounting flange (13).

12. Lift out the main pump and flange. Lifting

weight: 147kg.

Installation

The installation sequence is just opposite to the removal sequence.

Pay attention to the following technical requirements during installation:
Tightening torque of main pump mounting screw M20-10.9: 600±55N.m; before mounting, it is necessary
to apply thread locker on the screw thread (TONSAN 1277).
Tightening torque for angle seal threaded joint with O-ring: G1/4: 37.5±2.5N.m; G3/8: 75±5N.m; G3/4:
165±15N.m.
Tightening torque for 24° cone seal thread hose joint with O-ring: M18×1.5: 37±2N.m; M30×2:
126±6N.m;
 7-95
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.7 Removal and Installation of Main Pump Assembly

7.5.7 Removal and Installation of Main Pump Assembly

Part drawing of main pump

Part number involved in the chapter is based on the following drawing:

7-96
7.5 Hydraulic System December 30, 2017
7.5.7 Removal and Installation of Main Pump Assembly CLG930E/936E
 7-97
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.7 Removal and Installation of Main Pump Assembly

The structural chart and parts of the pilot pump are listed as follows:
The parts numbers of the pilot pump involved in this section are not in accordance with the following
figure but the specified numbers.

Structure drawing of pilot pump

LG936E07097

307 Spool 312 Locknut 361 End cover 700 Seal ring
308 Valve seat 351 Pump body 433 Bolt 710 O-ring
309 Snap ring 353 Drive gear 434 Bolt 725 O-ring
310 Spring 354 Driven gear 435 Bolt 732 O-ring
311 Adjusting bolt 355 Oil filter 466 Screw plug 850 Snap ring
887 Pin

Disassembly

Precautions
1. The digits in the bracket behind the part number represent the serial number of the part in the
exploded view of the pump.
2. Be careful not to mix the parts various types of pumps.
3. To avoid damage to the inclination pin head, remove the inclination pin with the special clamp.
4. The joint surface between the inclination pin and the auxiliary piston is coated with polystirene. Avoid
damage to the auxiliary piston.
7-98
7.5 Hydraulic System December 30, 2017
7.5.7 Removal and Installation of Main Pump Assembly CLG930E/936E

5. Considering the bearing life, do not pull out the needle roller bearings as far as possible.
6. Do not loosen the valve body and the hexagonal nuts on the support table for the sloping plate.
Doing so can change the flow setting.
7. The following dismantling includes those of the pump body and the regulator.

Disassembly of pump body

Figures Procedure
1. Select the site for removal.
Notice: Select a clean and tiny site, place
rubber plate or working cloth on the operation
platform to prevent damaging the parts.
2. Please remove the dirt, rust from the pump
—— surface using cleaning oil.
3. Remove the oil plug cap (468) from the pump
housing and pump out the oil in the pump body.
Notice: For the tandem pump, drain the oil
from the pin clamp of front pump and rear
pump.
4. Dismantle the hexagon socket bolt to remove
the regulator, and then remove the gear pump.
 7-99
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.7 Removal and Installation of Main Pump Assembly

Figures Procedure
5. Remove the PTO device

6. Unscrew the hexagon socket bolt with washer

to remove the gear pump (04).

7. Unscrew the hexagon socket bolt (401)

connected to swashplate supporting platform
(251), pump housing (271) and mating cover
(F) (311).
8. After removing the hex positioning screw (956),
unscrew the hexagon socket bolt (402)
connected to swashplate supporting platform
(251), pump housing (271) and mating cover
(R) (312) as the same of the 5th item.
Notice: Unscrew the hexagon socket bolt
rather than remove it.
7-100
7.5 Hydraulic System December 30, 2017
7.5.7 Removal and Installation of Main Pump Assembly CLG930E/936E

Figures Procedure
9. Put the regulator on the operation platform
horizontally with the mounting face downward,
and separate the pump housing (271) and oil
distributor (312).
Notice: When the mounting face of the
regulator facing downwards, put rubber plate
on the operation platform so as to prevent the
mounting face from being damaged.
Notice: When separate the pump housing
from the oil distributor, take down the 1st gear
(116) simultaneously

10. Pull out the cylinder body (141) from pump

housing (271) straightforwards based on the
drive shaft (111,113), and meanwhile remove
the plunger pair (151,152), return plate (153),
sphere bushing (156), and return spring (157).
Notice: Protect the sliding surface of
cylinder block, sphere bushing, skid shoes and
swash plate from being damaged.
Notice: Do not damage the drive shaft
bearing.

11. After separating the mating cover (F) (311) and

(R) (312), remove the booster(130) on the
spline coupling (114) connecting with the drive
shaft(111)(113).
12. Separate the pump housing (271) from the
—— mating cover (R) (312) from the R side. And
then pull out the cylinder body (012) from pump
housing (271) straightforwards based on the
drive shaft (111,113), and meanwhile remove
the plunger group (011), return plate (153),
sphere bushing (156), and return spring (157).
 7-101
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.7 Removal and Installation of Main Pump Assembly

Figures Procedure
13. Remove hexagon socket bolt (406) to remove
the sealing cap (F) (261).
Notice: There is a hole (M6 threaded hole)
for unplugging on the sealing cap (F) for ease
of taking it out after installing the bolt.
Notice: As the sealing cap (F) is
equipped with oil seal, do not damage the oil
seal at removal.

14. Knock the rear end of the drive shaft (111, 113)
gently so as to separate the drive shaft from
swashplate supporting platform (251).

15. Remove the shoe plate (211) and swashplate

(212) from the pump housing (271).
7-102
7.5 Hydraulic System December 30, 2017
7.5.7 Removal and Installation of Main Pump Assembly CLG930E/936E

Figures Procedure
16. Knock the fitting flange part of the swashplate
supporting platform (251) on the pump housing
side gently to separate the swashplate
supporting platform and the pump housing.
17. Remove the mating plate (313, 314) from the
mating cover (311, 312).
Notice: The mating plate may fall off while
it is in the 9th and 11th operation.

18. Remove stopper (L) (534), stopper (S) (535),

servo plunger (532) and tilt pin (531) from the
pump housing (271) in accordance with the
necessity. Furthermore, remove the needle
bearing (124) from the oil distributor (312).
Notice: While removing the tilt pin, protect the
head of the tilt pin from being damaged and
remove it with clamp.
Notice: Because thread lock is applied on the
—— mating part of tilt pin and servo plunger, protect the
servo plunger from being damaged.
Notice: Except for considering the needle
bearing life, try not to remove it.
Notice: Never unscrew the inner hexagon
nuts on oil distributor and swashplate supporting
platform randomly. Otherwise, the setting flow
will be changed.
Notice: It may fall off while it is in the 7th
operation
 7-103
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.7 Removal and Installation of Main Pump Assembly

Disassembly of regulator

Figures Procedure
For the part number involved in the following, refer
to the part drawing of regulator in the main pump
assembly introduction of "structure function and
maintenance".
1. Select one disassembly site.
Notice: Select one cleaning site.
Notice: In order to protect the parts from
being damaged, rubber plate or operation-used
cloth, etc. shall be laid on the operation
platform.
2. Wash out the dust, rust, etc. on the surface of
regulator with cleaning oil.
3. Remove the hex screw (438) and take down
the cap (C) (629).
Notice: The cap (C) (629) has been
installed with the adjusting wheel (C) (627),
adjusting screw (C) (628), locknut (630), hex
nut (801, 802), and adjusting screw (924).
Notice: Never loosen these screws or
nuts. If they are loosened, the setting
pressure—flow will be changed.
4. After removing the cap (C) (629), remove the
outer ring spring (625), inner ring spring (626)
and spring holder (C) (624) from the
compensator part, and pull out the regulating
ring (Q) (645), guide spring (646) and spring
holder (644) from the pilot part.
Notice: It is easy to remove the regulating
ring (Q) (645) by using M4 screw.
7-104
7.5 Hydraulic System December 30, 2017
7.5.7 Removal and Installation of Main Pump Assembly CLG930E/936E

Figures Procedure
5. Remove hex screw (436438), and remove the
pilot cover (641); after removing pilot cover
(641), please take out the pin (898) and Pf
bushing (631) from the compensator, and then
remove the set spring (655) from the pressure
regulator part.

6. Remove the snap ring (814), spring holder

(653), restoring spring (654), and bushing
(651).
Notice: The snap ring (836) fixes bushing
(651), and while removing snap ring (814),
restoring spring (654) can pop. Protect the
restoring spring from losing.

7. After removing lock ring (858), remove the

center plug (614) and adjusting plug (615).
Notice: It is easy to remove center plug
(614) and adjusting plug (615) with M6 bolt.
 7-105
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.7 Removal and Installation of Main Pump Assembly

Figures Procedure
8. Remove lever (2) (613), but do not pull out pin
(875).
Notice: It can make the operation easier to
use a pair of tweezers.

9. Push out the pin (874), and remove the

feedback rod (611).
Push out the pin (874) (pin diameter φ4) with slimy
steel bar, and meanwhile, avoid hitting rod (1)
(612).

10. Remove lever (1) (612), but do not pull out pin
(875).
11. Remove the pilot plunger (643) and spool (652)
12. Remove the plunger bushing (622),
compensator plunger (621) and compensator
rod (623).
These are the complete operating steps.
Notice: During removal of plunger bushing
(622), it can be extruded from the compensator
rod (623) end on the opposite side to plunger
bushing (622).
7-106
7.5 Hydraulic System December 30, 2017
7.5.7 Removal and Installation of Main Pump Assembly CLG930E/936E

Removal of pilot pump

Figures Procedure

Notice: Select a clean site. Lay rubber

plates or cloth, etc. for removal, and be careful
not to damage parts.
1. After removing pilot pump (1) from main pump,
find a clean site to disassemble it.

2. Place the pilot pump shaft end (2) downwards.

Notice: Because input shaft of pump is
more protuberant than mounting face, it is best
to provide supporting objects on the two ends
of the mounting face.

3. Remove four mounting screws (3) on the pump

cover from the upper end.
 7-107
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.7 Removal and Installation of Main Pump Assembly

Figures Procedure
4. Pull out the upper cover (4) of pilot pump
upwards slowly and gently.
Notice: be careful in operation and not to
damage the mounting face.

5. Put the upper cover aside. Remove O-ring

carefully.

O-ring
Notice: The damaged O-ring cannot be
reused.

6. Grasp one end of driven gear, and pull out the

driven gear (5) straight up slowly.
Notice: Make the mark and note the fitting
direction of driven gear.
Notice: Protect supporting shaft on two
ends of gear and the mounting face matched
with it from damage.
7-108
7.5 Hydraulic System December 30, 2017
7.5.7 Removal and Installation of Main Pump Assembly CLG930E/936E

Figures Procedure
7. Grasp one end of drive gear, and pull out the
driven gear (6) straight up slowly.
Notice: Make the mark and note the fitting
direction of drive gear.
Notice: Protect supporting shaft on two
ends of gear and the mounting face matched
with it from damage.

Assembly

1. Repair the damaged section during removal, and prepare replaceable parts in advance.

2. Thoroughly clean each part with cleaning oil, and dry with compressed air.

3. Assembly must be carried out after the slide part and bearing are applied with clean working
oil.

4. O-ring, oil seal and other seals shall be replaced in principle.

 7-109
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.7 Removal and Installation of Main Pump Assembly

Assembly of pump body

1. The assembly sequence is just opposite to the removal sequence. Pay attention to the assembly of
the following items.
2. Repair the damaged section during removal, and prepare replaceable parts in advance.
3. Thoroughly clean each part with cleaning oil, and dry with compressed air.
4. The clean working oil must be applied to the spindle section and the center joint body before
assembly.
5. O-ring, oil seal and other seals shall be replaced in principle.
6. Prepare torque wrenches used for mounting bolts and oil plugs at each section, and tighten them
with the torques specified in the table below.
7. On the occasion where pumps are in series, components of front pump and rear pump shall not mix
together.
8. Mounting Torque Table is as follows:
Specifications and torque of pilot pump

No. Name Specifications Tightening torque

1 Bolt M8X60 17 N.m
2 Bolt M8X50 17 N.m
Specifications and torque of pump body and regulator

Parts name Specifications Mounting torque (N•m)

M5 6.9
M6 12
M8 29
Hex bolt M10 57
M12 98
M14 160
M16 240
M18 330
M20 430
PT heavy bolt RC1/16 6.9
RC1/8 10
Note: twine it with sealing tape RC1/4 17
1.5-2 circles RC3/8 34
RC1/2 49
ROH oil plug G1/4 36
G3/8 74
G1/2 110
G3/4 170
G1 190
G 1 1/4 270
7-110
7.5 Hydraulic System December 30, 2017
7.5.8 Disassembly and Assembly of PTO Pump CLG930E/936E

7.5.8 Disassembly and Assembly of PTO Pump

Disassembly

If removal and installation shall be conducted, pay special attention not to damage machined
surface, that excessive force will cause eccentricity or serious damage to part.
If the part is difficult to install during assembly, it is possible to tap it with soft hammer (do not
use a metal hammer).
Handle them gently during removal and installation to avoid damaging shaft diameter or tooth
surface

Figures Procedure
1. Place the pump in the vise with drive gear
facing down. During assembly and removal
Notice: Do not tension the machined
surface. Make line on each part and align the
marking line in case of reinstallation.

2. Loosen the 4 bolts with allen wrench.

 7-111
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.8 Disassembly and Assembly of PTO Pump

Figures Procedure
3. Lift up the rear cover.
Notice: If it is necessary to pry up, take
care not to damage the machined surface.

4. Take down the intermediate body.

Notice: If it is necessary to pry up, take
care not to damage the machined surface.

5. Mark the hyponymy relation of shaft sleeve.

Remove the shaft sleeve. Check for
replacement.
7-112
7.5 Hydraulic System December 30, 2017
7.5.8 Disassembly and Assembly of PTO Pump CLG930E/936E

Figures Procedure
6. Mark the position relation among gears by
making line.

7. Remove the drive and driven gears carefully.

Keep the tooth surface away from other hard
objects, check for replacement.

8. Carefully remove the shaft sleeve

subassembly from the front cover, check for
replacement.
 7-113
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.8 Disassembly and Assembly of PTO Pump

Figures Procedure
9. Pry out oil seal.
Notice: Take care not to damage seal hole
surface inside front cover.

10. Check all the shaft sleeve subassembly

surface for scratches or discoloration, and
replace them if necessary.
7-114
7.5 Hydraulic System December 30, 2017
7.5.8 Disassembly and Assembly of PTO Pump CLG930E/936E

Assembly
Figures Procedure
1. Clean the seal hole thoroughly. The sealant
shall be used during installation of metal outer
diameter seal.
Notice: use grease instead of sealant on
the rubber outer oil seal

2. Place the new seal on the special tool. The

side with spring faces outward.

3. Press the seal into the bottom of seal hole

 7-115
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.8 Disassembly and Assembly of PTO Pump

Figures Procedure
4. Inspect O-ring. It is recommended to use new
one instead of keeping seal ring in the seal
groove.

5. To install new sealing parts, the seal comes

first, with support on top.

6. Install the front bearing subassembly to cover,

and fix the seal with grease.
7-116
7.5 Hydraulic System December 30, 2017
7.5.8 Disassembly and Assembly of PTO Pump CLG930E/936E

Figures Procedure
7. Set the protective sleeve to drive gear. Apply a
small amount of grease to lubricate the seal
during assembly.

8. Insert the shaft to pass through the cover

completely and then take away the protective
sleeve.

9. Install the driven gear to the shaft sleeve

subassembly.
 7-117
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.8 Disassembly and Assembly of PTO Pump

Figures Procedure
10. Installed intermediate body.

11. Installed O-ring. Apply the seal groove with

grease.

12. Install the rear shaft sleeve subassembly and

pay attention to the direction.
7-118
7.5 Hydraulic System December 30, 2017
7.5.8 Disassembly and Assembly of PTO Pump CLG930E/936E

Figures Procedure
13. Installed rear cover

14. Install the bolt and washer, and tighten the bolt
to the cover in diagonal manner with specified
torque.
Notice: Do not apply grease to thread prior
to assembly.
 7-119
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.9 Removal and Installation of the Travel Pilot Valve Assembly

7.5.9 Removal and Installation of the Travel Pilot Valve Assembly

Removal

Before removing hydraulic lines, lower the work implement to the ground completely, shut down
the engine, turn the key to the KEYON position, operate all hydraulic control levers several times
to release the residual pressure from the hydraulic system,and then press the exhaust button of
hydraulic oil tank breather valve to release the internal pressure from the oil tank.

Before removing the lines, fittings or hoses, make the marks so as to prevent wrong installation
while restoring. Clean the periphery of the assembled oil port as required, and put a drip pan to
receive oil.
Seal the lines, fittings or hoses with plugs or caps when they are in disassembling state, so as to
prevent pollution source from entering the hydraulic system.

Figures Procedure
1. Remove the bottom plate (1) under the foot
pilot.
7-120
7.5 Hydraulic System December 30, 2017
7.5.9 Removal and Installation of the Travel Pilot Valve Assembly CLG930E/936E

Figures Procedure
2. Remove the 6 pilot pipes (2).

3. Remove 2 joints (3).

4. Remove antislip step(4) with cross screwdriver;

remove floor mat (5) and rubber pedal (6).
 7-121
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.9 Removal and Installation of the Travel Pilot Valve Assembly

Figures Procedure
5. Remove 4 bolts with wrench to remove pedal
(7).

6. Remove 4 captive bolts (8) and then remove

foot pilot valve upwards.

Installation

The installation sequence is just opposite to the removal sequence.

Pay attention to the following technical requirements during installation:
Tightening torque of joint: 36±2Nm;
Tightening torque of hose joint: 26±2Nm;
7-122
7.5 Hydraulic System December 30, 2017
7.5.10 Disassembly and Assembly of Travel Pilot Valve CLG930E/936E

7.5.10 Disassembly and Assembly of Travel Pilot Valve

Part drawing of the travel pilot valve

For the part numbers involved in the section, this part drawing below shall prevails.

101 Housing 212 O-ring 301 Slide valve 423 Positioning screw
102 Housing 213 O-ring 311 Spring seat 431 Seat
153 Oil plug 214 Push rod 313 Washer 471 Positioning screw
191 Valve seat 215 Washer 324 Spring 472 Locknut
194 Steel ball 217 Washer 335 Spring 473 Hexagon socket bolt
201 Valve cover 218 Spring seat 336 Spring 501 Rubber sleeve
202 Screw plug 220 Hexagon socket bolt 337 Spring 520 Pedal
203 Grease fitting 224 Piston 412 Bushing 521 Pedal sleeve
210 Grease fitting 225 Steel ball 413 Cam shaft 522 Hexagon socket bolt
211 O-ring 271 Hex screw 420 Cam
 7-123
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.10 Disassembly and Assembly of Travel Pilot Valve

Disassembly

Special tool

For removing bushing


!"#

1. There shall be a capacious site to place the removed components and parts. Prepare a stable
workbench where components and parts will not fall off and roll during operation.
2. Prepare tools and related materials.
3. All components and parts have been processed precisely.Be careful in the operation and pay
attention to hold and put swiftly and do not crash or drop the components.
4. Do not consider that all components and parts are solid and firm. During removal, the excessive
beat, pry and cut will lead to trimming, deformation and damage, which causes unable to assemble,
oil leak as well as performance reduction. Therefore, operate with cautions and patience.
5. No corresponding disposal or random placement in removing midway after removing, which will
cause rusted components and parts because of humidity and impurity. When the operation must be
interrupted, pay attention to take the measures of rust protection and dust prevention.
7-124
7.5 Hydraulic System December 30, 2017
7.5.10 Disassembly and Assembly of Travel Pilot Valve CLG930E/936E

Figures Procedure
1. Clean the pilot valve with white kerosene,
Notice: All connectors are blocked with
plugs.
2. Fix the pilot valve on the bench vice with buffer
plate (the copper plates or other soft plates).
Remove the pedal cover (521) from pedal
(520), and remove it from the upper side.

3. Loosen the hexagon socket bolt (522) with the

inner hexagon spanner, and remove the pedal
(520) .

4. Loosen the hexagon socket bolt (473) with the

inner hexagon spanner, and remove the seat
(431).
 7-125
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.10 Disassembly and Assembly of Travel Pilot Valve

Figures Procedure
5. Remove rubber bushing (501) from the upper
side of valve cap (201).

6. Unscrew the positioning screw (423) with inner

hexagon spanner.
Notice: The required release torque is
larger due to applied with threaded locker.

7. Align the round rods (below φ8) with the one

end of the cam shaft (413), and then beat it
with hammer to remove it.
7-126
7.5 Hydraulic System December 30, 2017
7.5.10 Disassembly and Assembly of Travel Pilot Valve CLG930E/936E

Figures Procedure
8. Unscrew positioning screw (471) and locknut
(472) on the cam (420), and remove them in
pair.
Notice: Record the position relationship
between the cam and valve cap (201).
Notice: During removal, please note the
push rod (214) may be ejected.

9. Unscrew the hex screw (271) with the inner

hexagon spanner.

10. Remove valve cap (201).

Notice: Record the position relations
between the valve cap and the buffer housing
(102).
Notice: During removal, please note the
push rod (214) and push rod bushing (202) may
be ejected because of the elastic forces of the
buffer springs (336), (337).
(The push rod bushing may not be ejected from
buffer housing because of the sliding resistance of
the O-ring (212) )
 7-127
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.10 Disassembly and Assembly of Travel Pilot Valve

Figures Procedure
11. Remove push rod (214) from plug (202).
Notice: Record the position relation
between plug and push rod.
Notice: Be careful not to damage the
surface of the push rod.
Notice: During removal, pay attention that
the plug may be ejected.

12. Remove plug (202) together with lubricating oil

cup (203) and NHU oil cup (210).
Notice: Record the position relations
between the plug and the buffer housing.
Notice: During removal, please note the
plunger may be ejected because of elasticity of
the buffer spring.

13. Remove the plunger (224) from the bumper

housing.
Notice: Record the position relationship
between the plungers and the bumper housing
holes.
7-128
7.5 Hydraulic System December 30, 2017
7.5.10 Disassembly and Assembly of Travel Pilot Valve CLG930E/936E

Figures Procedure
14. Remove the buffer springs (336), (337) from
the buffer housing.
Notice: Record the position relationship
between the buffer spring and the bumper
housing hole.

15. Remove the spring seat (218) from the buffer

housing.
Notice: Record the position relations
between the spring seat and the bumper
housing hole.

16. Take out the steel ball (225) with magnet, etc.
Notice: Keep the steel balls without lose.
 7-129
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.10 Disassembly and Assembly of Travel Pilot Valve

Figures Procedure
17. Loosen the hexagon socket bolt (220) with the
inner hexagon spanner.

18. Remove the buffer housing (102).

Record the position relations between the buffer
housing and the housing (101).
Notice: During removal, please note the
pressure reducing valve group can be ejected
because of the elastic force of the reset spring
(335).

19. Remove the O-ring (211) and the O-ring (213)

from the valve body.
7-130
7.5 Hydraulic System December 30, 2017
7.5.10 Disassembly and Assembly of Travel Pilot Valve CLG930E/936E

Figures Procedure
20. Remove the pressure reducing valve group
and reset spring (335) from the housing.
Notice: Record the position relationship
with the valve body hole.

21. Place the valve cap (201) on the platform

horizontally, then align the special tool 1 to the
bushing (412), knock at it gently with the
hammer, and remove the bushing.
 7-131
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.10 Disassembly and Assembly of Travel Pilot Valve

Figures Procedure
22. Fix the cam group on the bench vices, loosen
the locknut (472) with spanner, and remove the
locknut and positioning screw (471).
Notice: Because the positioning screw
must be adjusted as per the central position
when assembling, it will be kept in form of cam
group in the subsequent process if the screw
is not required to be replaced.

23. For removal of Pressure Valve GP. Place the

slide valve (301)which should be vertical and
upright on the flat operation table, depressing
the spring holder (311), and then remove the 2
round washers (215) with the head of a small
straight screwdriver.
Notice:Be careful not to damage the
surface of the slide valve.
Notice: Notice:The depressing scope
should not be more than 4mm for the spring
holder.

24. Separate the slide valve (301), spring holder

(311), spring (324) for secondary pressure
setting, washer (215) and washer (313).
Notice:Keep in a group form until
assembling.
Notice: Notice: Washer 215 is used for
presetting and adjustment of spring for
secondary pressure setting; the thickness of
each slide valve is different. It may also not be
used.
7-132
7.5 Hydraulic System December 30, 2017
7.5.10 Disassembly and Assembly of Travel Pilot Valve CLG930E/936E

Figures Procedure
25. Remove lubricating oil cup (203) from plug
(202).

26. Remove NHU oil cup (210) from plug (202).

Please remove with plastic sheet bars or other
tools.
Notice: Do not touch the inner surface of
plug.

27. Remove (O) seal ring (212) from the plug

(202).
 7-133
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.10 Disassembly and Assembly of Travel Pilot Valve

Figures Procedure
28. Fix the housing (101) on the bench vice with
buffer plates (the copper soft plate, etc.), and
then loosen the oil plug (153) with inner
hexagon spanner. (Only for PVD8PC)

29. Pull out the valve seat (191) from the housing
(101). (Only for PVD8PC)

30. Take out the steel ball (194) from the

housing(101). (Only for PVD8PC)
Notice: Remove the steel ball with magnet.
7-134
7.5 Hydraulic System December 30, 2017
7.5.10 Disassembly and Assembly of Travel Pilot Valve CLG930E/936E

Cleaning of components and parts

● Put all components and parts into a coarse cleaning container with white kerosene, and clean them.
(Coarse cleaning)
● If all parts are cleaned initially in the unclean oil, those parts can be damaged easily, therefore, clean
them after fully immersed and the impurities and grease are floating.
● The unclean white kerosene will damage components and parts and reduce the performance after
reassembly, therefore keep the white kerosene clean completely.
● Put all components and parts into a cleaning container with white kerosene, and clean while rotating
them until the inside is clean (after cleaning operation). Clean the white kerosene adhering on
components and parts with clean cone screw.
● If drying with compressed air, the components and parts can be damaged and rusted because of
impurity and moisture in compressed air, so do not use it.

Rust protection of components and parts.

● Apply anti-rust agent on components and parts.

● After cleaning, placing them without rust prevention will result in rust. And the function will not be
carried out fully after reassembling.

Assembly

1. The same as the removal get the operation platform, tools and related data ready.

2. During assembling, give the same attention to the general precautions as the removing.

3. Metal scraps and foreign matters of all parts during assembling shall be eliminated. Moreover,
ensure there is no trimming, damage, bruise, etc. on the components and parts. If there is above-
mentioned situation, please remove it with oil stone.

4. In principle, replace with new products for the O-ring and NHU seal ring.

5. When installing the O-ring and NHU seal ring, pay attention not to damaging them. (For easy
assembly, please apply little grease)

6. When assembling components and parts, please use grease to prevent dropping.

7. Fasten the bolts, etc. according to mounting torque as shown in assembly sectional diagram.

8. All connectors shall be sealed with plugs after installing to avoid intrusion of impurities.
 7-135
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.10 Disassembly and Assembly of Travel Pilot Valve

Figures Procedure
1. Fix the housing (101) with buffer plates (the
copper plates and other soft materials) on the
bench vice, and install the steel ball (194) into
the housing (101). (Only for PVD8PC)
Notice: Attract the steel balls to the weak
magnets, or install them with tweezers, etc.

2. Install the valve holder (191) into housing

(101).
(Only for PVD8PC)

3. Install oil plug (153) according to the specified

torque.
(Only for PVD8PC)
7-136
7.5 Hydraulic System December 30, 2017
7.5.10 Disassembly and Assembly of Travel Pilot Valve CLG930E/936E

Figures Procedure
4. Install washer (313), washer (217), spring
(324) for secondary pressure setting, and
spring holder (311) to the slide valve (301) in
sequence.
Notice: Notice: Washer 2 is used for
presetting and adjustment of spring for
secondary pressure setting; the thickness of
each slide valve is different. It may also not be
used.

5. Place the lower end of slide valve (301)

vertically and uprightly on the flat workbench,
depress the spring holder (311), and then
install half-round washer (215) on the spring
holder upside. Do not make the washer overlap
in two slices.
Notice: Make the acute angle side (no arc
side) of washer 1 face upward. Be sure not to
force to install the slide valve head or install
improperly.
Notice: Notice:The depressing scope
should not be more than 4mm for the spring
holder.
Notice: Make the acute angle side (no arc
side) of washer 1 face upward. Be sure not to
force to install the slide valve head or install
improperly.
Notice: Notice:The depressing scope
should not be more than 4mm for the spring
holder.

Acute angle
side
 7-137
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.10 Disassembly and Assembly of Travel Pilot Valve

Figures Procedure
6. Install the reset spring (335) into valve body.
Notice: Install it according to the position
before removal.

7. According to above No.4 item, install the

pressure reducing valve group in group form
into the valve body.
Notice: Install it according to the position
before removal.

8. When installing pressure reducing valve

group, note not let the lower end of slide
valve to excessive impact the valve angle.

Note the valve body angle

7-138
7.5 Hydraulic System December 30, 2017
7.5.10 Disassembly and Assembly of Travel Pilot Valve CLG930E/936E

Figures Procedure
9. Install the O-ring (211) and O-ring (213) on the
valve body.

10. Install the buffer housing (102) and housing

(101) together with hexagon socket bolt (220),
and fasten them according to the specified
torque.
Notice: Install it according to the position
before removal.
Notice: Evenly screwed the 2 hexagon
socket bolts (220) in, and keep the buffer
housing (102) fastened in parallel.

11. Attract the steel ball (225) to the weak magnet,

or install it into the buffer housing (102) with
tweezers, etc.
 7-139
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.10 Disassembly and Assembly of Travel Pilot Valve

Figures Procedure
12. Install the spring seat (218) into buffer housing.
Notice: Install it according to the position
before removal.

13. Install the buffer spring (336) into buffer

housing.
Notice: Install it according to the position
before removal.

14. Install the buffer spring (337) into buffer

housing.
Notice: Install it according to the position
before removal.
Notice: Do not make it engage with the
buffer housing (336).
7-140
7.5 Hydraulic System December 30, 2017
7.5.10 Disassembly and Assembly of Travel Pilot Valve CLG930E/936E

Figures Procedure
15. Install piston (224).
Notice: Install it according to the position
before removal.

16. Install O-ring (212) onto the plug (202).

17. Install NHU oil cup (210) into push rod bushing.
Notice: Note the direction when installing
NHU seal ring.
Notice: It is easier to install it when NHU
seal ring is applied with a layer of grease
before installing.
 7-141
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.10 Disassembly and Assembly of Travel Pilot Valve

Figures Procedure
18. Install lubricating oil cup (203) into push rod
bushing.

19. Install the push rod (214) into the push rod
bushing.
Notice: The push rod surface shall be
applied with hydraulic oil before installing.
Notice: Do not force to insert it because it
may damage the lip edge of NHU seal ring.

20. According to (15) (16) (17) (18) items, the push

rod group shall be installed into the buffer
housing in the group form.
7-142
7.5 Hydraulic System December 30, 2017
7.5.10 Disassembly and Assembly of Travel Pilot Valve CLG930E/936E

Figures Procedure
21. Compress the bushing (412) on the valve cap
(201) with the special tool 1, and then knock at
it with a hammer to press it into the cover.
Notice: When compressing the bushing,
note not to knock out the inner side of cover.

22. Install the cover to the buffer housing.

Notice: Install it according to the position
before removal.
Notice: the cover may be ejected because
of the elastic force of the buffer springs (336),
(337).
 7-143
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.10 Disassembly and Assembly of Travel Pilot Valve

Figures Procedure
23. Install and fasten the hexagon socket bolt
(271) according to the specific torque.
Notice: The cover should be installed
horizontally without deflection.
Notice: Install the positioning screw (471)
to the cam (420), and install the locknut (472)
temporarily.

24. Install the cam (420) on the cover.

Install it according to the position before
removal.
7-144
7.5 Hydraulic System December 30, 2017
7.5.10 Disassembly and Assembly of Travel Pilot Valve CLG930E/936E

Figures Procedure
25. Press the cam (420); meanwhile insert the
camshaft (413) into the cam from outside.

26. The surface of the hex positioning screw (423)

shall be applied with the thread rubber #241 or
other equivalent.

27. Install and fasten the hex positioning screw

(423) according to the specified torque.
 7-145
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.10 Disassembly and Assembly of Travel Pilot Valve

Figures Procedure
28. Adjust the height of the positioning screw
(471), parallel the cam (420) upside with the
cover underside, and turn the cam right and
left. After confirm that the cam will not be loose
in the neutral position, install and fasten the
locknut 472 according to the specified torque.
Notice: Attach the 4 push rods (214) to
appropriate positions with the positioning
screws. When over-tightening the positioning
screws, the control lever shall be loose in the
neutral position and acute movement will
happen when starting the engine and attention
shall be paid to this.

29. After tilting the cam, the push rod top side shall
be applied with the grease; meanwhile the
grease cup (203) of the plug (202) shall be
filled with grease.
Notice: When applying and filling the
grease, please do not damage the push rod
and the surface of the plug, and conduct with
soft flat material.

30. After inserting the upper end of rubber cover

(501) into cam, insert the lower end into the
slot of cover.
Notice: Before the rubber bushing lower
end is inserted into the cover groove, spray the
injection-type anti-rust oil onto the
components and parts in the rubber bushing.
Notice: If the rubber bushing is not
inserted into the groove properly or installed in
a distorting state, the dust tightness and
waterproofness shall be reduced.
7-146
7.5 Hydraulic System December 30, 2017
7.5.10 Disassembly and Assembly of Travel Pilot Valve CLG930E/936E

Figures Procedure
31. Install the seat (431), and install and fasten the
hexagon socket bolt (473) according to the
specified torque.

32. Install the pedal (520), and install and fasten

the hexagon socket bolt (522) according to the
specified torque.

33. At last, install the pedal cover (521) on the

pedal (520).
 7-147
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.12 Removal and Installation of Hand Pilot Valve Assembly

7.5.12 Removal and Installation of Hand Pilot Valve Assembly

Removal of the left hand pilot valve assembly

Before removing hydraulic lines, lower the work implement to the ground completely, shut down
the engine, turn the key to the KEYON position, operate all hydraulic control levers several times
to release the residual pressure from the hydraulic system,and then press the exhaust button of
hydraulic oil tank breather valve to release the internal pressure from the oil tank.

Before removing the lines, fittings or hoses, make the marks so as to prevent wrong installation
while restoring. Clean the periphery of the assembled oil port as required, and put a drip pan to
receive oil.
Seal the lines, fittings or hoses with plugs or caps when they are in disassembling state, so as to
prevent pollution source from entering the hydraulic system.

Figures Procedure
1. Pull out rubber jacket (1) of pilot valve, unplug
wire (2), remove locknut (3) of control lever,
and then remove the control lever.
7-148
7.5 Hydraulic System December 30, 2017
7.5.12 Removal and Installation of Hand Pilot Valve Assembly CLG930E/936E

Figures Procedure
2. Remove 4 mounting bolts (4) from the console,
and move the console cover out.

3. Remove 4 captive bolts (5) from hand pilot.

4. Pull out hand pilot slightly, and remove 6 pilot

pipes (6).
5. Remove the hand pilot valve.
 7-149
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.12 Removal and Installation of Hand Pilot Valve Assembly

Installation of left-hand pilot valve

Install the left-hand pilot valve assembly according to opposite procedures of removal. Wherein
tightening torque of connector: 36±2Nm;
Tightening torque of hose joint: M18×1.5: 37±2Nm.

Removal and installation of the right-hand pilot valve

By referring to removal and installation of left-hand pilot valve, remove and install right-hand pilot valve.
7-150
7.5 Hydraulic System December 30, 2017
7.5.12 Disassembly and Assembly of the Hand Pilot Valve Assembly CLG930E/936E

7.5.12 Disassembly and Assembly of the Hand Pilot Valve Assembly

Part drawing of hand pilot valve

This section introduces disassembly and assembly of two types of hand pilot valves, and the two types
can be installed on the machine. Please identify the type firstly, and then disassemble and assemble it in
accordance with the corresponding type.

All components and parts have been processed precisely. Pay attention to handling with care
and not crashing or dropping components and parts.
Remove without beating, prying and cutting; otherwise the components will be produced with
trimming, deformation and damage, which will result in failing to assemble, oil leak and
performance reducing. Therefore, please operate with caution and patience.
Suggest continuous operating. If the operation is interrupted, please adopt the rust-proof and
dust-proof measures.

For the part numbers involved in the section, this part drawing below shall prevails.
PV48K1 model
 7-151
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.12 Disassembly and Assembly of the Hand Pilot Valve Assembly

PV48KC1 model
7-152
7.5 Hydraulic System December 30, 2017
7.5.12 Disassembly and Assembly of the Hand Pilot Valve Assembly CLG930E/936E

Disassembly

Figures Procedure
1. Clean the pilot valve with white kerosene.
Notice: Seal the connectors with plugs.
2. Fix the pilot valve on the bench vive.
3. Remove the ripple protection cover (501).
Notice: Be careful not to break the ripple
protection cover (501).

4. Clamp distance between the adjusting nut

(312) and the disk (302) with spanner. Remove
adjusting nut and disk.
 7-153
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.12 Disassembly and Assembly of the Hand Pilot Valve Assembly

Figures Procedure
5. Rotate the connector (301) to the left with
clamp and then loosen it.
Notice: When the elastic force of the
restoring spring (221) is large, the cover (151),
the push rod bushing (211) and the push rod
(212) may be ejected at the time of unscrewing
the connector (301). When pulling out the
connector, they may also be ejected out.

6. Remove the cover (151).

7-154
7.5 Hydraulic System December 30, 2017
7.5.12 Disassembly and Assembly of the Hand Pilot Valve Assembly CLG930E/936E

Figures Procedure
7. The push rod bushing (211) may be blocked in
the valve body (101) because of the weak
restoring spring (221) and the O-ring slide
resistance, and please remove it with a straight
screwdriver.
Notice: Utilize the bushing peripheral
groove under the condition of the bushing
(211) not being damaged result from deflection.
Notice: The push rod bushing (211) may
be ejected because of the elastic force of the
restoring spring (221).

8. Pull out the push rod (212), push rod bushing

(211), the pressure reducing valve group and
restoring spring (221) from the valve body
(101).
Notice: Record the position relations of
the valve body holes.

9. Keep the interface plate (111) upward, and fix

the pilot valve on the bench vice with the
copper plate.
10. Loosen the oil plug (293) with inner hexagon
spanner. (Only for PV48KC1)
 7-155
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.12 Disassembly and Assembly of the Hand Pilot Valve Assembly

Figures Procedure
11. Pull out the valve seat (291) from the interface
plate (111). (Only for PV48KC1)

12. Remove the steel ball (292) with the magnet,

etc. from the interface plate (111). (Only for
PV48KC1)

As shown in the figure, hold the valve seat and pull it out.
Pay attention not to damaging the joint surface of steel ball.

Sel Steel
ball
Steel ball
ball

Valve seat
7-156
7.5 Hydraulic System December 30, 2017
7.5.12 Disassembly and Assembly of the Hand Pilot Valve Assembly CLG930E/936E

Figures Procedure
13. Loosen the hexagon socket bolt (125) with the
inner hexagon spanner.

14. Remove the interface plate (111) O-ring (122)

from the valve body (101).
15. Pull out the bushing (131) from the valve body
(101).
 7-157
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.12 Disassembly and Assembly of the Hand Pilot Valve Assembly

Figures Procedure
16. For removal of the pressure reducing valve,
depressing the spring holder (216) to
compress the secondary pressure spring (241)
and meanwhile make the spring holder (216)
crosswise a bit and pass via the bigger hole
side, and then remove the slide valve (201).
Then separate the slide valve (201), the spring
holder (216), the secondary pressure spring
(241) and the washer (217).
Notice: don't damage the surface of the
slide valve (206).
The room for further compressing of the spring
holder (216) is no more than 6 mm.
Keep it well in the group form until reassembly.

17. When installing the spring (246) and spring

holder (218) of two segmented breaking,
remove it from the push rod (212).

218
246 212
7-158
7.5 Hydraulic System December 30, 2017
7.5.12 Disassembly and Assembly of the Hand Pilot Valve Assembly CLG930E/936E

Figures Procedure
18. Pull out the push rod (212) from push rod
bushing (211).

19. Remove the O seal ring (214) and seal ring

(213) from the push rod bushing (211) with
small straight screwdriver or other tools.
 7-159
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.12 Disassembly and Assembly of the Hand Pilot Valve Assembly

Precautions for cleaning the components:

1. Put components and parts into a cleaning container filled with white kerosene and clean them
roughly.
2. Put components and parts into a cleaning container filled with white kerosene, rotate slowly and
clean them until insides of them are completely clean. Wipe up white kerosene adhering to
components and parts with clean rag after cleaning.
3. Components and parts need soaking sufficiently, and clean them after impurities and grease float.
4. Unclean white kerosene can damage components and parts, and it can cause degradation of their
performance after assembling them, so it shall guarantee the cleanness of white kerosene.
5. Impurities and moisture in compressed air can cause rust, therefore do not dry them with
compressed air.

Rust prevention of components and parts

Apply anti-rust onto components and parts If they are placed without rust prevention after rinse, this may
cause rust and then affect their performances.

Assembly

Metal scraps and foreign matters of all parts during assembling shall be eliminated. Moreover,
ensure there is no trimming, damage, bruise, etc. on the components and parts. If there is above-
mentioned situation, please remove it with oil stone.
O-rings and protective washers shall be replaced with new ones in principle.
While installing the O-ring and the protective washer, take care not to damage them. (Please
apply a little lubricating grease for easy installation and smoothness)
When assembling components and parts, please use grease to prevent it dropping.
All connectors shall be sealed with plugs after installing to avoid impurities.
7-160
7.5 Hydraulic System December 30, 2017
7.5.12 Disassembly and Assembly of the Hand Pilot Valve Assembly CLG930E/936E

The table below shows tightening torque value of mounting torque of bolts, etc. Measure
mounting torque value with torque wrench.

Functional Thread
Tool(s) Size (mm) Mounting torque (N·m)
parts specification
Hexagon socket
Inner hexagon spanner 6 M8 20.6±1.5
bolt
Inner hexagon spanner
5 ROH oil plug G1/8 11.8±1.0
Only (PV48KC1 specification)
22 Adjusting nut M14
Wrench 68.6±4.9
32 Disc M14
Special clamp is shown in figure
24 Joint M14 47.1±2.9
LG922E930E07283.

Figures Procedure
1. Place mounting surface of interface plate (111)
upward and fix the pilot valve with the copper
board.
2. Install bushing (131) and O-ring (122) on valve
body (101).
 7-161
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.12 Disassembly and Assembly of the Hand Pilot Valve Assembly

Figures Procedure
3. Put the gasket (121) between interface board
(111) and valve body (101), and fix it with
hexagon socket bolt (125).
Notice: Pay attention to the assembling
position, when assemble the spring pin (126) in
the hole of the valve body(101).
Notice: The gasket(121) shall be replaced
with a new one.
7-162
7.5 Hydraulic System December 30, 2017
7.5.12 Disassembly and Assembly of the Hand Pilot Valve Assembly CLG930E/936E

Figures Procedure
4. Fix the hexagon socket bolts (125) with an
inner hexagon spanner according to specified
torque.
Notice: While installing, screw them in
pairs alternately and slowly.

5. Install the steel ball (292) into the interface

plate (111) with magnet, etc. (PV48KC1)
6. And then install the valve seat (291) into the
interface plate (111). (Only for PV48KC1)
 7-163
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.12 Disassembly and Assembly of the Hand Pilot Valve Assembly

Figures Procedure
7. Fix the oil plug (293) as per specified torque
with an inner hexagon spanner. (Only for
PV48KC1)

8. Install washer 2(217), secondary pressure

spring (241), and spring holder (216) in
sequence into slide valve.
Then press in the spring holder (216) to com-
press the secondary pressure spring (241) as
stagger the spring holder (216) horizontally a
bit. And, put it through the hole and then install
it onto the slide valve (201).

Notice: The room for further compressing

of the spring holder (216) is no more than 6
mm.
7-164
7.5 Hydraulic System December 30, 2017
7.5.12 Disassembly and Assembly of the Hand Pilot Valve Assembly CLG930E/936E

Figures Procedure
9. Install the restoring spring (221) into the valve
body (101). Install pressure reducing valve
group into the valve body (101).
Notice: Install it according to the position
before removal.

10. Install the O-ring (214) on the push rod bushing

(211).

211

11. Install the seal ring (213) onto the push rod
bushing (211).
Notice: Please install the seal ring (213) in
lip direction as shown in the figure below.
 7-165
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.12 Disassembly and Assembly of the Hand Pilot Valve Assembly

Figures Procedure
12. Install the push rod (212) into the push rod
bushing (211).
Push rod
bushing If there is a spring (246) and a spring holder
Sealing
(218) used for two segmented breaking, install
them onto the push rod (212).

Notice: Apply working oil onto the surface

Push of the push rod (212).
rod Apply operating oil

Notice: Be careful not to leave the slide

valve tilted (201), otherwise, it will cause
damage to the hole of the valve body (101).
7-166
7.5 Hydraulic System December 30, 2017
7.5.12 Disassembly and Assembly of the Hand Pilot Valve Assembly CLG930E/936E

Figures Procedure
13. Install the push rod group into the valve (101).
Notice: When elasticity of the restoring
spring (221) is weak, the spring may not pop up
because of sliding resistance of the O-ring
(214).
Notice: When the restoring spring (221) is
strong, the cover (151) can be used to install 4
joints (301) temporarily at the same time.
Notice: pay attention to the pop out of the
push rod bushing group and the cover (6).
 7-167
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.12 Disassembly and Assembly of the Hand Pilot Valve Assembly

Figures Procedure
14. Install it on (151).
15. Install the connectors (301) onto the valve
body (101) according to specified torque with
clamp.

101

16. Install disk (302) on the connector (301).

Notice: adjust the 4 push rods (212) to an
even contacting position, and then install
screws. If the screws are over screwed, it may
cause the base machine malfunction because
the control lever placed in the neutral position
may produce secondary pressure. So pay
special attention to the adjustment of to
screwing position of disc (302) screws.
7-168
7.5 Hydraulic System December 30, 2017
7.5.12 Disassembly and Assembly of the Hand Pilot Valve Assembly CLG930E/936E

Figures Procedure
17. Here is the way to adjust nuts (312). Clamp
opposite sides of the disc (302) with wrench
and install it on, then fix the adjusting nut (312)
as per specified torque.
Notice: While installing, do not move the
disc (302).

18. Apply grease onto swing parts of connectors

(301) and the top of the push rod (212).

19. Install crease shield (501).

Notice: Don't break the ripple protection
cover (501).
20. Add anti-rust to each port, and then install the
plug.
 7-169
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.13 Removal and Installation of the Travel Motor & Reduction Gear,

7.5.13 Removal and Installation of the Travel Motor & Reduction Gear,

Removal

Before removing hydraulic lines, lower the work implement to the ground completely, shut down
the engine, turn the key to the KEYON position, operate all hydraulic control levers several times
to release the residual pressure from the hydraulic system,and then press the exhaust button of
hydraulic oil tank breather valve to release the internal pressure from the oil tank.

Attach the identification label to each pipe to prevent wrong installation in the subsequence
procedures.
Before removing the lines, fittings or hoses, make the marks so as to prevent wrong installation
while restoring. Clean the periphery of the assembled oil port as required, and put a drip pan to
receive oil.
Seal them with plugs or caps when the lines, connectors or hoses are in disassembling state to
prevent pollution sources from entering the hydraulic system.

Figures Procedure
1. Refer to the method for the removal of the track
assembly to remove it.
2. Remove the 5 bolts (1) and remove the
blanking plate from the travel motor.
7-170
7.5 Hydraulic System December 30, 2017
7.5.13 Removal and Installation of the Travel Motor & Reduction Gear, CLG930E/936E

Figures Procedure
3. Disconnect the return pipe (2) and the elbow
joint (3).
4. Disconnect the two high-pressure pipes (4).
5. Disconnecting the pilot pipe (5).

6. Remove the 26 bolts (6), and then remove the

sprocket.

7. Binding the travel motor with sling, adjust the

rope to the center-of-gravity position, and
straining it with hoisting equipment slowly.
 7-171
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.13 Removal and Installation of the Travel Motor & Reduction Gear,

Figures Procedure
8. Remove 18 mounting bolts (7).
9. Remove the travel motor.
Lifting weight: about 399kg.

Installation

Figures Procedure
1. Install the travel motor in track beam, and the
motor oil port shall orient the underframe side.
7-172
7.5 Hydraulic System December 30, 2017
7.5.13 Removal and Installation of the Travel Motor & Reduction Gear, CLG930E/936E

Figures Procedure
2. Clean bolt hole, apply thread locker Tonsan
1277 to mounting bolt, tighten the bolt timely,
and apply corresponding pretightening force to
the bolt in symmetrical cross strengthening
method.
Tightening torque is 1020±90N.M.

3. Clean bolt hole, apply thread locker Tonsan

1277 to mounting bolt, tighten the bolt timely,
and apply corresponding pretightening force to
the bolt in symmetrical cross strengthening
method.
Tightening torque: 600±55N.m.

4. Tighten pilot pipe, oil return pipe and two high-

pressure pipes.
M18 pilot hose tightening torque: 37±2N.m
Tightening torque of M22 oil return pipe: 47±2Nm
Tightening torque of M36 high pressure pipe:
179±8Nm
 7-173
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.13 Removal and Installation of the Travel Motor & Reduction Gear,

Figures Procedure
5. Tighten the plate mounting bolts of the travel
motor.
Tightening torque: 305±25Nm.
7-174
7.5 Hydraulic System December 30, 2017
7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear CLG930E/936E

7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear

Disassembly and assembly of the travel motor

Structure diagram of travel motor

The serial numbers behind the names of the parts below should be based on the following drawings:

1. Housing 17.Shoe brake 32.The pin (MRC03) 47.O-ring1BP12.5

2. NPT1 / 16 screw plug 18.Plunger group 33.Spring seat (MRC03) 48.M6 throttle valve (φ0.8)
3. Oil Seal 19.Meshing plate 34.Spring(MRCO3) 49.O-ring 1B P15
4. Locating ring IRTW68 20.Friction plate 35.the pilot valve screw plug 50.O-ring 215.57×2.62
5. Expansion plug MB800- 21.Piston brake G3/8 51.Bearing HR32207C
040 22.D-ring (small diameter) 36.O-ring 1B P11 52.Shim
6. Tilt piston 23.D-ring (large diameter) 37.Connecting pipe 53.Parallel valve pin
7. Piston sealing 24.Motor rear cover (MRCO3) m68×12
8. Steel ball 25 25.NPT1 / 16 screw plug 38.G1 / 4 screw plug 54.Mating plate
9. Drive shaft (red) 39.O-ring 1B P11 55.Brake spring
10.Bearing HR32207C 26.Spool group (M4V RBV) 40.Throttle valve (brake 56.Hexagon socket bolt
11.Pivot 27.Spring seat valve) M18×50
12.Swash plate (M4V290RBV) 41.Spring (brake valve) 57.The safety valve ORV-
13.Cylinder block 28.Spring(M4V150RBV) 42.G1 / 8 screw plug 240L
14.Cylinder block spring 29.the M42 screw plug 43.O-ring 1B P8 58.Connector
15.Spring seat (M4V290RBV) 44.Check valve 59.Snap ring
16.Ball joint 30.O-ring 1B G40 45.Check valve spring 60.G1 / 2 screw plug
31.Pilot spool (M4V290) 46.M6 throttle valve φ 61.O-ring 1B P18
 7-175
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear

Special tool

Piston brake installer

Compression mold (2 units)

Hexagon socket bolt 2-M6X100

Piston brake drawer (2 units)

LG936E4F07118
7-176
7.5 Hydraulic System December 30, 2017
7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear CLG930E/936E

Oil seal installer

Guide pins for motor cover

(2 units)

Bearing installer
 7-177
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear

Disassembly

Precautions

6. Kerosene and other combustible materials are used for cleaning the parts.

Pay great attention to combustible materials. Failure to do so may cause a fire.

7. The dismantled parts are coated with gear oil, resulting in slipping off.

Be sure to treat the parts. Slipping off of any part can cause personal injury or the part damage.

8. The hydraulic machine is precise and has many small gaps in structure. It needs to be dismantled
and re-assembled in a clean area without dust. In addition, keep the tools and cleaning agents clean.
9. After the motor is removed from the machine, clean the area around each interface and then remove
each plug. Be sure to prevent oil dirt and water from entering into the motor.
10. Before dismantling, study the figure above. Prepare the necessary components based on the part to
be dismantled.
11. The piston and the cylinder block are not paired. To re-use them, mark the piston and the cylinder
block during removal. So as to match them when assembling.

Always prevent your hand from being clamped into the parts. Prevent your feet from being hit by
any lifted part.
7-178
7.5 Hydraulic System December 30, 2017
7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear CLG930E/936E

1. Dismantling the affiliated valve

Figures

Before the motor is removed, remove its affiliated valve.

Notice: According to the purpose of dismantling, not removing the affiliated valve
outside the dismantling scope is the best.
However, to dismantle the motor, you have to remove the safety valve (57).
Notice: Do not dismantle the motor until its temperature drops to the room
temperature. Otherwise, you can be seriously scalded.
1. Remove the M42 screw plug (29) and O-ring (30).

Disasse 2. Remove the spring (28), spring seat (27) and spool group (26)
mbly Notice: Mark the spool group (26) and the rear cover (24). Failure to do so can
steps cause reverse installation.

3. Remove the plug (42), O-ring (43), throttle valve spring (41) and throttle valve (40).
4. Remove the safety valve (57).
Notice: During this period, the valve seat (57-3) can easily slip off. Check whether
the valve seat falls into the rear cover (24) or is lost.
5. Loosen the pilot valve screw plug (35), and remove the O-ring (36), the spring (34), the
spring holder(33), the pilot spool (31) and the pin (32).
6. Remove the connector (58).
 7-179
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear

2. Disassemble the motor.

Guide bar

Figures

Notice: The following sections describe how to dismantle the motor separately.
After the reduction gear is assembled, it can be dismantled similarly. The main shaft
will not shake significantly, so it is better to dismantle the motor with the reduction
gear.
1. Place the motor shaft horizontally. Remove the hexagon socket bolts M18 × 50 (56), but
leave two of them diagonally.
2. Install two guide bars in the diagonal positions. (Purpose: They are used to prevent
Disasse
slipping off when removing and to guide when assembling.)
mbly
steps 3. Loosen the two reserved hexagon socket bolts M18 × 50 (56) gradually.
4. Remove the rear cover (24) and the brake spring (55). Make sure the cylinder (13) is
carefully taken away together with the rear cover (24).
Notice: Always prevent your hand from being clamped into the parts. Prevent
your feet from being hit by any lifted part.
Notice: Do not let the mating plate (54), the brake spring (55), the bearing bush
(51), the gasket (52), the O-rings (50), (47) and (49) fall to the ground.
Notice: There is a gasket (52) in the bearing bush. Avoid its loss during removal.
7-180
7.5 Hydraulic System December 30, 2017
7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear CLG930E/936E

Figures

5. Do not bring the cylinder block (13) out when the mating plate (54) is removed.
Notice: Mark the mating plate (54) and the rear cover (24). Failure to do so can
cause reverse installation.
Disasse
6. Press the cylinder block downward with tool and expose the bearing inner ring; notice not
mbly
bruise the cylinder block (13) surface; refer to above figure.
steps
Notice: To protect the cylinder (13) surface, put a rubber pad between the cylinder
surface and the tool.
7. Hook the bearing (51) inner race with the puller to remove it.

Oil hole

Figures
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December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear

8. The piston brake can be pulled out with the tool. To remove the piston brake (21), install
the tool into the M6 screw hole on the surface of the piston brake (21). Roll the paper into
a barrel and insert it into the plunger hole, and then mark the outer surface of the cylinder
Disasse block.
mbly
9. Remove the rotating group (including the cylinder (13), the plunger (18), the shoe brake
steps
(17), the ball joint (16), the spring seat (15) and the cylinder spring (14)).
Notice: Always prevent your hand from being clamped into the parts. Prevent
your feet from being hit by any lifted part.

Figures

Mark

Fitting mark

10. Remove the mesh plate (19) and the friction plate (20).
11. Remove the plunger (18), the shoe brake (17) and the ball joint (16) from the rotating
group.
12. Remove the spring seat (15) and the cylinder spring (14) from the cylinder.
Disasse Notice: Install the plunger (18) into the cylinder (13) according to the marks. Make
mbly sure that the plunger is installed into the hole which is the same as the one before
steps dismantling.

Notice: Avoid damage to each contact surface. If damaged, do not use the
plunger again.
Notice: The plunger and the shoe are pressed together. They cannot be
dismantled.
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7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear CLG930E/936E

Oil hole

Figures

13. Remove the swashplate (12)

14. 1,2-speed piston does not need to be removed. If necessary, hold the piston by
hand, and then push it out from the via hole with air pressure.
Disasse
mbly Notice: The air pressure may blow the 1 and 2-speed piston away. Be very dangerous,
steps
15. Pull out the main shaft (9)
16. If the bearing (10) needs to be replaced, pull out its inner race with the puller, and then
replace the bearing with a new one.

Figures
 7-183
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear

Notice: When the parts associated with the bearing, such as bearings (10) (51),
main shaft (9), housing (1), rear cover (24) or the like, need to be replaced, adjust the
gasket (52).
Determine the gasket gap accurately, and then replace the gasket with the
corresponding one.
Disasse
mbly Adjust the bearing clearance to the range of 0-0.1mm.
steps Notice: Generally, the pivot (11) does not need to be removed. If necessary, mark
the corresponding swashplate (12).
Notice: Generally, the oil seal (3) does not need to be removed. If necessary,
replace it a new one.
To do so, remove the locating ring (4) and then remove the oil seal (3).

Figures
7-184
7.5 Hydraulic System December 30, 2017
7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear CLG930E/936E

17. Calculation of tapered bearing gasket (52) thickness

Notice: This needs to be implemented only when one of the motor housing (1),
the rear cover (24) and the bearing (10) (51) is replaced.
(1) Under the assembly state shown in the figure above, measure the size E.

Disasse Notice: Make sure the main shaft (9) is not inclined.
mbly (2) Measure the size F on the side of the rear cover (24)
steps
Notice: Be sure to measure four points on the circumference in a crisscross
pattern and take their average.
(3) If the gasket (52) thickness is defined as S, the gap Y may be calculated as follows: Y=F-
(E=S)
(4) Make sure the gap Y is within 0-0.01mm, and select one or two gaskets (52).

3. Dismantling the safety valve

Figures

Disasse
The safety valve is an important part in performance and safety. It is very difficult to re-set its
mbly
pressure. If a malfunction happens, do not dismantle it but replace the valve assembly.
steps
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December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear

Grease

Figures

Notice: The valve seat (57-3) is fitted in the gap of the inner hole of the sleeve (57-
Disasse 1). Do not let the valve seat (57 -3) fall off when removing the safety valve (57) from the
mbly motor cover (24).
steps Further, when the safety valve (57) is assembled into the motor cover, to prevent the
valve seat (57 -3) from falling off, grease the joint surface.

Assembly

Precautions
1. Clean the parts thoroughly with cleaning fluid and dry them with an air gun.
2. Be sure to apply the hydraulic oil to the sliding parts before assembling them.

Always prevent your hand from being clamped into the parts. Prevent your feet from being hit by
any lifted part.

Oil seal installer

Figures
7-186
7.5 Hydraulic System December 30, 2017
7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear CLG930E/936E

1. Grease the outer ring of the oil seal (3) and the inner ring of the housing (1), and then tap
the oil seal (3) into the housing (1) gently using the seal installer.
2. Fix the oil seal (3) with the locating ring (4).
Assemb 3. Install the outer race of the front bearing into the housing (1) (clearance fit). Press the
ly steps inner race in the main shaft (9) (interference fit).
Notice: To press in the inner race easily, you can heat it to 100°(or below).

Notice: Take care to avoid being scalded.

Figures

4. Fix the main shaft (9) to the housing (1). Be sure to grease the seal contact surface.
5. Assemble the obliquely-rotating plungers (6), (7) and (8).
Notice: Be sure to set the obliquely-rotating plunger right and then insert it.
Assemb Notice: When inserting the obliquely-rotating plunger, grease its sealed portion.
ly steps Avoid damage to the plunger.
6. When assembling the pivot (11), be sure to install it on the side which is consistent with
the matching mark of the swashplate (12). In addition, for long-term operation, install it in
the direction in which the sliding mark on the sphere is consistent with the contact mark
of the swashplate (12).
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CLG930E/936E 7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear

Figures

7. Grease the three spherical surfaces of the swashplate (12) fully before assembling.
8. Install the plunger group (18), shoe brake (17), ball joint (16), spring holder(15), cylinder
spring (14) and cylinder (13) into an assembly, and then insert the assembly into the
main shaft (9).
Assemb
Notice: Always prevent your hand from being clamped into the parts. Prevent
ly steps
your feet from being hit by any lifted part.
Notice: Be sure to insert the plunger group (18) into the same hole as that before
dismantling the cylinder.
9. Insert the front bearing inner race into the main shaft (9) using the special tools (A1, A2).

Soft part of inner race

Soft part of outer race

The front of the machine

Figures
7-188
7.5 Hydraulic System December 30, 2017
7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear CLG930E/936E

10. Assemble the mesh plates (19) and the friction plates (20) alternately. The first one and
the last one should be the mesh plate (19).
11. Insert the piston brake (21) with D-rings (22) and (23) in the housing (1) with the special
tools.
Assemb Notice: Grease the D-rings (22) and (23).
ly steps
Notice: Insert the piston brake (21) evenly with the special tools. The piston brake
is equipped with D-rings (22) and (23). Install the large-diameter D-ring (23) first, and
then install the small-diameter D-ring (22). The installation state of the small-diameter
D-ring (22) cannot be visually confirmed. Do not force to install it.
The hole on the housing (1) can be cut sometimes.

Guide
pin

Figures
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December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear

Notice: When the related parts need to be replaced, adjust the gaskets.
Determine the gasket thickness according to the Dismantling Essentials 3-2-2, Item (2) -18
[Requirements for Thickness of Gaskets for Tapered Roller Bearings], and then assemble
them.
12. Fix the guide pin to the diagonal position 2 of the housing (1).
13. According the matching marks made during dismantling, install the mating plate into the
motor cover, and then install the gasket (52), the front bearing (51) outer race, the brake
spring (55) and the O-rings (50), (47) and (49).
Assemb 14. Insert the motor cover (24) into the housing (1) along the guide pin. To allow the motor
ly steps cover to be installed parallel to the diagonal position (2), tighten it with the M18 × 50 (56)
hex bolts. If you finish, tighten the hex bolts other than the guide pin position (2). Then,
remove the guide pin, and tighten the hex bolts at the remaining two positions.
Notice: Always prevent your hand from being clamped into the parts. Prevent
your feet from being hit by any lifted part.
Notice: When the front bearing (51) outer race is removed, remember to install the
gasket (52).
Make sure the motor cover is equipped with the O-rings (47), (49) and (50).
Notice: Tighten the hex bolt M18 × 50 (56) to 324 ± 32.4N·m.
15. Install the connector (58).

Figures
7-190
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7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear CLG930E/936E

16. Install the spring (34), the spring holder(33), the pilot spool (31) and the pin (32) in the
motor cover (24), and then tighten the pilot valve screw plug (35) with O-ring (36).
Notice: Tighten the pilot valve screw plug (35 ) to 49.0~58.8N·m.
17. Install safety valve (57)
Notice: The valve seat (57-3) is installed at the position with clearance fit. During
installation, to prevent it from slipping off or falling off, grease the joint surface.
Notice: Tighten the safety valve (57) to 98.1~118N·m.
18. Install the check valve (40) and its spring (41) in the motor cover (24), and then tighten
Assemb the pilot valve screw plug (42) with O-ring (43).
ly steps
Notice: Tighten the plug (43) to 14.7N·m.
Notice: When the new check valve is needed, grease the sealing portion.
19. According to the matching marks made when dismantling, install the spool assembly (26)
into the motor cover (24), and then install the spring holder(27) and the spring (28)
sequentially.
Notice: The spool assembly (26) is directional. Insert the spool assembly with
care.
20. Tighten the M43 plug (29) with O-ring (30) . Tighten the M42 screw plug (29) to
441~461N·m.

Initial operation

1. Drain and add oil

After dismantling and assembling, fill the operating oil in the motor housing.
There are two drainage ports (G1/2) on the motor. Bleed the air using the port on the side without piping.
Notice: Perform the initial operation.
Check for noise, exterior leak and other anomaly at Speed 1 of the motor when five minutes after the
engine is started.

Disassembly and assembly of the reduction gear

Structure diagram of reduction gear

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December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear

The serial numbers behind the names of the parts below should be based on the following drawings:

Structural map for reduction gear

1. Housing 6. Shim 12.Needle bearing 17.Planetary gear 1 22.Sun gear 1

2. Bearing 7. Lock shim FBNP-608660 18.Thrust shim 1 23.Thrust plate
245BA35S1GS 8. Support ring 13.Gear pin 2 19.Needle bearing 24.Rear cover
3. Gear ring 9. Support 2 14.Spring pin 10×50 FBNP-406040 25.Hexagon socket
4. Hexagon socket 10.Planetary gear 2 15.Sun gear 2 20.Gear pin 1 bolt M10×30
bolt M18×110 11.Thrust shim 2 16.Support 1 21.Spring pin 6×36 26.Screw plug G3 / 4
5. Float seal ring 368 27.O-ring 1B P24
7-192
7.5 Hydraulic System December 30, 2017
7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear CLG930E/936E

Disassembly

Precautions
1. Like the precautions 1) -4) for dismantling the traveling motor.
2. When the reduction gear is removed from the machine, the reduction gear may be polluted by oil dirt.
Be sure to clean the reduction gear surface and dry it.

To avoid scalding, do not dismantle the reduction gear until its temperature drops to the room
temperature.

3. Unscrew and remove the drain plug and the fill plug G3 / 4 (26), and drain the gear oil in the
reduction gear.

Dismantling the reduction gear when its gear oil is hot can cause the pressured oil to spray out.

4. To re-install the parts easily, be sure to mark the outside of each corresponding surface.

Figures Procedure
1. Remove the reduction gear from the traveling
motor and reduction gear.
2. Lift the reduction gear onto the work bench.
Remove three hexagon socket bolts M10×30
(25)installed in the rear cover equally. Then install
the lift rings.
Notice: Always prevent your hand from
being clamped into the parts. Prevent your feet
from being hit by any lifted part.
Notice: Be sure to lift the reduction gear
up horizontally.
 7-193
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear

Figures Procedure
3. Remove the rear cover of the reduction gear.
(1) Remove the remaining hexagon socket bolts
M10 × 30 (25).

(2) The joint surface between the rear cover (24)

and the ring gear (3) is glued. Be sure to tap
the rear cover upward and obliquely using a
metal liner to withstand the rear cover.
Notice: Always prevent your hand from
being clamped into the parts. Prevent your feet
from being hit by any lifted part.

4. Remove the bracket 1.

(1) Remove the thrust plate (23).
(2) Install three M10 eyebolts on the bracket 1
(16). Lift up the brackets (16,17, 18,19, 20, 21)
overall.
Notice: Always prevent your hand from
being clamped into the parts. Prevent your feet
from being hit by any lifted part.
Notice: Be sure to lift the reduction gear
up horizontally.
(3) Remove the sun gear 1 (22).
Notice: Do not put your hands between the
gears. Doing so can cause hand injury.
7-194
7.5 Hydraulic System December 30, 2017
7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear CLG930E/936E

Figures Procedure
5. Remove the bracket 2.
(1) Remove the sun gear 2 (15).
Notice: Do not put your hands between the
gears. Doing so can cause hand injury.
(2) Install three M10 eyebolts on the bracket 2 (9).
Lift up the brackets (9,10, 11,12, 13 and 14)
overall.
Notice: Always prevent your hand from
being clamped into the parts. Prevent your feet
from being hit by any lifted part.
Notice: Be sure to lift the reduction gear
up horizontally.

6. Disassembly and assembly of Outer housing

(1) Remove the support ring (8).

(2) Put a screwdriver against the opening of the

lock washer (7) and knock it out with a
hammer.
 7-195
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear

Figures Procedure
(3) Install three M10 eyebolts into the ring gear
equally and lift out the housing assembly
(including ring gear (3), housing (1), bearing
(2), floating seal ring (5), hexagon socket bolts
M18 × 110 (4)) horizontally
Notice: Always prevent your hand from
being clamped into the parts. Prevent your feet
from being hit by any lifted part.
Notice: Be sure to lift the reduction gear
up horizontally.

7. Removal of housing
(1) Install three eyebolts into the housing (1)
equally. Let the ring gear (3) face down and the
housing (1) face upward, and then lift them
onto the work bench. Mark the outside of the
housing and ring gear (3).
Notice: Always prevent your hand from
being clamped into the parts. Prevent your feet
from being hit by any lifted part.
Notice: Be sure to lift the reduction gear
up horizontally.
7-196
7.5 Hydraulic System December 30, 2017
7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear CLG930E/936E

Figures Procedure
(2) Remove the floating seal ring (5).
(3) Remove the hexagon socket bolts M18 × 110
(4), but leave two on the diagonal positions.
(4) Unscrew the two reserved bolts and tap the
housing and ring gear gently with the hammer
to separate the housing from the ring gear
easily.
Notice: Always prevent your hand from
being clamped into the parts. Prevent your feet
from being hit by any lifted part.
Notice: Avoid damage to the sliding metal
surface of the floating seal ring (5) and the O-
ring.
Notice: The bearing (2) outer race is fitted
with the housing (1) inner diameter closely. Do
not remove the bearing (2) unless it has to be
replaced. Do not re-use the bearing removed
from the housing (1). Be sure to replace it.
8. Remove the floating seal ring on the side of the
motor head.
Remove the floating seal ring (5) on the side of the
motor head.
 7-197
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear

Figures Procedure
9. Remove the bracket 1.
Notice: If the gear pin 1 (10) needs to be
re-used, before removing, make the same mark
on both the gear pin 1 and the mounting hole.
For follow-up matching.
(1) Tap the spring pin 6 × 36 (21) into the gear pin
1 (20).
(2) Remove the gear pin 1 (20) from the bracket 1
(16).
(3) Remove the thrust shim 1 (18), the planetary
gear 1 (17) and the needle bearing (19) from
the bracket 1 (16).
Notice: Do not put your hands between the
gear and the bracket. Doing so can cause hand
injury.
Notice: If the gear pin 1 (20) or the
planetary gear 1 (17) needs to be replaced,
replace all the three ones.
7-198
7.5 Hydraulic System December 30, 2017
7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear CLG930E/936E

Figures Procedure

10. Remove the bracket 2.

Notice: If the gear pin 2 (13) needs to be
re-used, before removing, make the same mark
on both the gear pin 2 (13) and the mounting
hole. For follow-up matching.
(1) Tap the spring pin 10 × 50 (14) into the gear pin
2 (13).
(2) Remove the gear pin 2 (12) from the bracket 2
(9).
(3) Remove the thrust shim 2 (11), the planetary
gear 2 (10) and the needle bearing (12) from
the bracket 2 (9).
Notice: Do not put your hands between the
gear and the bracket. Doing so can cause hand
injury.
(4) Remove the spring pin 10×50(14)from the gear
pin 2(13).
Notice: If the gear pin 1 (20) or the
planetary gear 1 (17) needs to be replaced,
replace all the three ones.
 7-199
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear

Figures Procedure
7-200
7.5 Hydraulic System December 30, 2017
7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear CLG930E/936E

Assembly

Precautions
1. 1 Clean the parts thoroughly with cleaning fluid and dry them with an air gun. Degrease the surface
with sealant using the thinner or the like.
2. Check whether each part is normal.
3. Coat each hex bolt with #242 and tighten it.
4. Before assembling each assembly, apply a thin layer of gear oil to it.
5. Remove the residue from the thread position with sealant using a screwdriver and degrease the
thread position.

Always prevent your hand from being clamped into the parts. Prevent your feet from being hit by
any lifted part.

6. Be sure to use a torque wrench for tightening operation.

Tightening Torques

Part
Part name Dimension Tightening torque (N·m)
symbol
378±37.8 N·m
4 Hex bolt M18×110
# 242 sealant coating
68.6±6.9N·m
25 Hex bolt M10×30
# 242 sealant coating
26 Hexagon screw plug G3/4 147±14.7N·m
 7-201
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear

Figures Procedure
1. Assembly of bracket 2 Ass’y.
(1) Insert the planetary gear 2 (10), needle bearing
(12) and thrust shim 2 (11) into the bracket 2
(9).
Notice: Do not put your hands between the
gear and the bracket. Doing so can cause hand
injury.
(2) Insert the gear pin 2 (13) into the bracket 2 (9)
toward the direction of the spring pin hole.
(3) Insert the spring pin 10 × 50 (14) into the
bracket 2 (9) and the gear pin 2.
(4) Caulk the two positions which are symmetrical
in 180°.
7-202
7.5 Hydraulic System December 30, 2017
7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear CLG930E/936E

Figures Procedure

Two caulking
positions which
are symmetrical in Based on the
Notice: For the direction of inserting the
Spring pin 180°, as shown in caulking, the spring pin and the caulking method, refer to
opening, as shown the figure. spring pin is
hidden by 0.5.
the left figure.
in the figure.

Front end settlement

1.0-2.0 of spring pin

2. Assembly of bracket 1 Ass’y.

(1) Insert the planetary gear 1 (17), needle bearing
(19) and thrust shim 1 (18) into the bracket 1
(16).
Notice: Do not put your hands between the
gear and the bracket. Doing so can cause hand
injury.
(2) Insert the gear pin 1 (20) into the bracket 1 (16)
toward the direction of the spring pin hole.
(3) Insert the spring pin 6 × 36 (21) into the
bracket 1(16) and the gear pin (20).
(4) Caulk the two positions which are symmetrical
in 180°.
Notice: For the direction of inserting the
spring pin and the caulking method, refer to
the left figure.
 7-203
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear

Figures Procedure

3. Installation of bearings and floating seals

(1) Install the bearing (2) in the inner diameter of
the housing (1).
(2) Install the floating seals (5) on one side of the
motor and one side of the housing,
respectively.
Notice: Remove the oil, impurities, paint
and foreign matters from the floating seal
installation positions.
Notice: Apply a thin layer of gear oil to the
sliding part of the floating seal (5). (Do not
apply gear oil to the O-ring.)
Notice: Make sure the floating seal (5) is
installed between the housing (1) and the motor in
parallel as shown in the left figure.
(The special tools are recommended.)
7-204
7.5 Hydraulic System December 30, 2017
7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear CLG930E/936E

Figures Procedure
4. Assembly of housing 1Ass’y
Sealant #515
(1) Apply the sealant #515 to the joint surfaces
between the housing (1) and the ring gear (3).
(2) Install the M20 eyebolts on the housing (1) and
lift it with the hoist. Install the ring gear (3)
based on the matching marks.
Notice: Always prevent your hand from
being clamped into the parts. Prevent your feet
from being hit by any lifted part.
Notice: Be sure to lift up the component
horizontally.

(3) Apply the # 242 sealant to the 25 hexagon

socket bolts M18 ×110 (4) and tighten them to
378 ± 38 • m.

Notice: For coating the bolts with sealant

#242, refer to the sealant #242 coating method
in the left figure.

Apply the #242 sealant to the front end of

the bolt
 7-205
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear

Figures Procedure
5. Angular contact bearing’s gasket thickness
requirements.
Notice: This must be done when any one
of the motor (case), the housing (1), the
(angular contact) bearing (2) and the lock
washer (7) needs to be replaced. If not the
above conditions, the gasket can be used as
usual.
(1) Install the two bearing (2) outer races in the
housing.
(2) Install the two bearing (2) outer races evenly
and measure the inner race’s assembly size.
Notice: When measuring the inner race’s
assembly size, rotate the bearing for more than
5 times before measuring.
(3) Measure the motor housing’s bearing size (B).
(4) Measure the motor housing’s lock washer
groove size (C).
(5) Measure the thickness (D) of lock washer (7).
Notice: Be sure to measure four points on
the circumference in a crisscross pattern and
take their average. Dimensional accuracy:
0.01mm.
(6) When the gasket (6) to be used is S thick, the
gap X is as follows. X=(B+C)-(A+D+S)
(7) In this case, the gasket with a gap X
(0.08~0.02mm) is selected.
7-206
7.5 Hydraulic System December 30, 2017
7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear CLG930E/936E

Figures Procedure
6. Assembly of housing Ass’y
Stamping
(1) Let the main shaft of the motor face upward
and put it onto the work bench. Select the
gasket (6) according to Section 4-3-2, Item (5)
[Requirements for Angular Contact Bearing
Thickness]. Then, put the gasket (6) on the
bearing mounting end face of the motor
housing.
Notice: Always prevent your hand from
being clamped into the parts. Prevent your feet
from being hit by any lifted part.
Notice: Be sure to lift up the component
horizontally.
(2) Install the three eyebolts (M10) in the ring gear.
Align the motor center and fall vertically. Insert
the bearing installed in the inner diameter of
the housing into the motor, and then align the
bearing inner race using the punching machine
to press the bearing inner race until it is
installed in place.
Notice: Always prevent your hand from
being clamped into the parts. Prevent your feet
from being hit by any lifted part.
Notice: Be sure to lift up the component
horizontally.
(3) Strain the groove of the lock washer (7) while
pressing the flange of the housing (1).
 7-207
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear

Figures Procedure
(4) Fix the support ring (8) to the outside of the
lock washer (7).

7. Assembly of bracket 2 Ass’y.

(1) Put the three planetary gears 2 (10) onto the
bracket 2Ass'y shown in the left figure and put
the 2Ass'y into the ring gear (3), and then let it
engage with the housing spline.
Notice: Always prevent your hand from
being clamped into the parts. Prevent your feet
from being hit by any lifted part.
Notice: Be sure to lift up the component
horizontally.
7-208
7.5 Hydraulic System December 30, 2017
7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear CLG930E/936E

Figures Procedure
(2) Insert the sun gear 2 (15).
Notice: Do not put your hands between the
sun gear and the other gear. Doing so can
cause hand injury.
Notice: The reason why the bracket 2Ass'y
is assembled at the position shown in the left
figure is that oil lubrication can be performed
well. Be sure to observe it.

8. Assembly of bracket 1 Ass’y.

(1) Lift up the bracket 1Ass’y using 3 bolts (M10)
and put it into the ring gear (3), and then turn
the matching position of the planetary gear 1
(17) to engage with the sun gear 2 (15).
Notice: Always prevent your hand from
being clamped into the parts. Prevent your feet
from being hit by any lifted part.
Notice: Be sure to lift up the component
horizontally.
(2) Make sure the connector is behind the main
shaft of the motor. Insert the sun gear 1 (22).
Notice: Do not put your hands between the
sun gear and the other gear. Doing so can
cause hand injury.
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December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear

Figures Procedure
(3) Insert the thrust plate (23) into the bracket (16).
Notice: Let the sharp corner point toward
the side of the rear cover (24).

Rear cover for

reduction gear

Sharp
corner

Thrust shim

9. Rear cover assembly

Notice: You fill the gear oil before
assembling the rear cover (24).
(1) Coat the matching surfaces of the rear cover
(24) and the ring gear (3) with sealant # 515,
and then fix the rear cover (24) to the ring gear
(3).
Notice: Always prevent your hand from
being clamped into the parts. Prevent your feet
from being hit by any lifted part.
(2) Coat the 18 hexagonal bolts M10 × 30 (25)
with sealant # 242, and tighten them to 68.6 ±
6.9N·m.
7-210
7.5 Hydraulic System December 30, 2017
7.5.14 Disassembly and Assembly of the Travel Motor & Reduction Gear CLG930E/936E

Figures Procedure
10. Filling of gear oil
(1) Pour the gear oil (SAE90, API classification
GL-4 or GL-5, 9.5 L) into the port G3/4.
(2) Install the hexagonal plug G3 / 4 (26) in the
rear cover (24) and tighten it to 147.1 ±
14.7N·m.
Notice: For coating the bolts with sealant
#242, refer to the #242 coating method in the left
figure.

Apply the #242 sealant to the

front end of the bolt

Inspection after assembling

1. Inspection of oil level

After the completion of assembly, let the leak port of the rear cover (24) be in the downward position
along the horizontal direction of the shaft, and then unscrew the horizontal plug to check for oil leak.
2. Rotation test
Put the motor on the test bench and let it run under no-load, and then check for abnormal noise or oil
leak.
 7-211
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.15 Removal and Installation of the Swing Motor & Reduction Gear

7.5.15 Removal and Installation of the Swing Motor & Reduction Gear

Removal

Before removing hydraulic lines, lower the work implement to the ground completely, shut down
the engine, turn the key to the KEYON position, operate all hydraulic control levers several times
to release the residual pressure from the hydraulic system,and then press the exhaust button of
hydraulic oil tank breather valve to release the internal pressure from the oil tank.

Before removing the lines, fittings or hoses, make the marks so as to prevent wrong installation
while restoring. Clean the periphery of the assembled oil port as required, and put a drip pan to
receive oil.
Seal them with plugs or caps when the lines, connectors or hoses are in disassembling state to
prevent pollution sources from entering the hydraulic system.

Figures Procedure
1. Remove the oil filler pipe (1);
2. Remove hose (2) of main oil filler;
3. Remove the oil return pipe (3).
7-212
7.5 Hydraulic System December 30, 2017
7.5.15 Removal and Installation of the Swing Motor & Reduction Gear CLG930E/936E

Figures Procedure
4. Remove 2 pilot pipes (4) of time delay valve.

5. Remove the bottom plate (5).

6. Remove block (6).

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December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.15 Removal and Installation of the Swing Motor & Reduction Gear

Figures Procedure
7. Remove the grease hose (7) on the bottom of
swing motor reduction gear.

8. Remove 11 captive bolts (8);

9. Apply lubricant on pin (9), and then remove it.

10. Lift the motors with rope and hoisting

equipment, and then place them on a clean
and safe position.
Lifting weight: 424kg.
11. Cover the installing port of the motor with
paperboard after it is lifted, so as to avoid
foreign matters falling into the port.
7-214
7.5 Hydraulic System December 30, 2017
7.5.15 Removal and Installation of the Swing Motor & Reduction Gear CLG930E/936E

Installation

Installation is in the reverse order of removal.

Mounting screw M24-10.9; tightening torque: 1020±90N.m;
Clean the threaded hole before the installation, and apply thread locker (Tonsan 1277) on the thread of
bolt.
Check whether the hydraulic oil is enough.
M18 pilot hose tightening torque: 37±2N.m
Tightening torque of M22 oil return pipe: 47±2Nm
Tightening torque for M26 oil drain pipe: 89 ± 4Nm
Tightening torque of M36 high pressure pipe: 179±8Nm
Tightening torque for M45 oil filler pipe: 226±11Nm
 7-215
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.16 Disassembly and Assembly of the Swing Motor & Reduction Gear

7.5.16 Disassembly and Assembly of the Swing Motor & Reduction Gear

Cross-section view of swing motor

马达部分剖面图

10 Piston 114 Spring bearer plate 301 H2 housing 452 Pin

20 H2 valve body assembly 123 Fixing plate 351 H2 piston 469 Screw plug
31 Time delay valve 124 Swashplate 355 H2 spring 712 Brake spring
33 Hexagon socket head 131 Valve fixing plate 390 Nameplate 742 Brake block
cap bolt 151 Screw plug 391 Pin 743 Isolation panel
51 Relief valve 161 O-ring 400 Anti-turnover valve 983 Plug
80 Seal package 162 O-ring 401 Hex screw 984 Plug
100 Valve body 163 O-ring 443 Roller bearing 985 Plug
101 Drive shaft 171 Hexagon socket head 444 Roller bearing
111 Cylinder cap bolt
7-216
7.5 Hydraulic System December 30, 2017
7.5.16 Disassembly and Assembly of the Swing Motor & Reduction Gear CLG930E/936E

Cross-section view of reduction gear

Plugged for transportation

Plugged for transportation

102 Valve body D2 230 No.2 carrier D 403 Positioning pin plug 909 Pin
104 Rear axle cover E 231 No.1 carrier D 601 hexagon head bolt 910 Pin
201 Drive shaft B 282 No.2 pin B 602 Hexagon socket head 912 snap ring
202 Gear ring E 283 No.1 pin B cap bolt 913 snap ring
203 No.2 planetary gear D 284 Push plate E 801 oil seal 915 Bearing seal ring
204 No.2 sun gear D 390 Nameplate 802 O-ring 922 Screw plug
210 No.1planetary gear D 391 Pin 903 Screw plug 925 Exhaust valves
211 No.1sun gear D 402 Self-aligning roller 904 Hexagon socket head 926 Grease fitting
bearing cap bolt 930 Hex screw
905 O-ring
 7-217
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.16 Disassembly and Assembly of the Swing Motor & Reduction Gear

Special tool

Remove the clamp used for bearing (401). Remove the clamp used for bearing (402).

Install the clamp used for oil seal.

Special tool used to remove brake plunger

7-218
7.5 Hydraulic System December 30, 2017
7.5.16 Disassembly and Assembly of the Swing Motor & Reduction Gear CLG930E/936E

Perforation

Disassembly

The chapter introduces the disassembly of swing motor & reduction gear in two parts, including:
1. Disassembly of swing motor
2. Disassembly of reduction gear

Choose a clean location. The disassembly platform shall be covered by rubber plate or cloth, etc.
in order to protect components from being damaged.
 7-219
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.16 Disassembly and Assembly of the Swing Motor & Reduction Gear

Disassembly of swing motor

Remove the motor in accordance with the following sequence. The number in the brackets following the
component name is the symbol shown in the installation profile view.

Figures Procedure
1. Tie the periphery of motor with steel wire rope,
lift it by crane, and then clean it with colorless
and transparent light oil. Blow and dry it with
compressed air after the cleaning.
Notice: Protect the motor from foreign
matters entering its inside. Wash mud and dust
adhered to the motor, and seal each hole with
adhesive tape.
2. Drain all working oil in the motor body from oil
drain hole.
3. Put the shaft end of drive shaft (101)
downwards, and then fix it on the operation
platform which is easy to be disassembled. At
this time, make the mark at the junction
position between motor body (301) and valve
body (303).
4. Loosen pressure-reducing valve (051) and
remove it from valve body (303).
Notice: O-ring may be destroyed while
loosening pressure-reducing valve, therefore,
be sure to replace the O-ring.
7-220
7.5 Hydraulic System December 30, 2017
7.5.16 Disassembly and Assembly of the Swing Motor & Reduction Gear CLG930E/936E

Figures Procedure
5. Remove ROMH oil drain plug (469) from valve
body (303), and then remove spring (355) and
plunger (351).
Notice: Protect the plunger valve seat from
being damaged.

6. Unscrew hexagon socket bolt (401), and then

remove valve body (303) from motor body
(301).
Because of the elastic force of brake spring (712),
valve body (303) may pop from motor body (301)
after the removal of bolt.
Remove the valve block (131) from valve body
(303).
Notice: Conduct the operation carefully so
as to protect valve block from falling off from
valve body. (For some motor, valve block is
installed on a side of cylinder.)
Notice: When prying the junction surface
with screwdriver, protect the junction surface
from being damaged.
 7-221
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.16 Disassembly and Assembly of the Swing Motor & Reduction Gear

Figures Procedure
7. Remove the brake spring (712) from the brake
plunger.

8. Pull out the brake plunger (702) from motor

body (301) with remover.
Notice: Hook the slot of brake plunger
using the remover paw end, and then lift it
vertically.

9. Level the motor again, and then pull out the

cylinder (111) from drive shaft (101). Pull out
the plunger (121), plate (123), plate spring and
plunger (124) in sequence.
Notice: Protect the revolving mating
surface of cylinder and plunger, etc. from being
damaged.
When it is not available to move the plunger out,
do it in the 12th operation step.
7-222
7.5 Hydraulic System December 30, 2017
7.5.16 Disassembly and Assembly of the Swing Motor & Reduction Gear CLG930E/936E

Figures Procedure
10. Remove friction plate (742) and metal plate
(743) of separator from motor body (301).

11. Remove drive shaft (101) and plunger (124).

Notice: The spline may destroy oil seal
during the removal of drive shaft, so twine the
spline part of drive shaft with plastic adhesive
tape before the removal.
 7-223
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.16 Disassembly and Assembly of the Swing Motor & Reduction Gear

Figures Procedure
12. Carry out the following operation steps in
accordance with the requirements.
Drive out the inner ring of cylindrical roller bearing
from drive shaft with press machine.
Notice: The inner ring of cylindrical roller
Punch press
bearing can also be knocked by hammer and
steel bar, but it is needed to knock the inner
ring uniformly and protect the bearing from
Drive shaft being damaged.
Notice: The removed bearing cannot be
reused.
13. Knock the outer ring of cylindrical roller bearing
gently with hammer and steel bar from one a
side of housing of oil seal (491), so as to
remove it from the motor body (301).
Notice: The removed bearing cannot be
reused.
14. Remove the cylindrical roller bearing (444)
from valve body (303) with sliding weight
bearing detacher.
Notice: The removed bearing cannot be
reused.
7-224
7.5 Hydraulic System December 30, 2017
7.5.16 Disassembly and Assembly of the Swing Motor & Reduction Gear CLG930E/936E

Disassembly of reduction gear

Figures Procedure
1. Lift the reduction gear with lifting device, and
then lay the drive shaft on the level ground.
Drain the gear oil from oil drainage port on the
gear.
2. Loosen hex screw (602) and remove the motor.
3. Remove No. 1 sun gear (211).
4. Remove No. 1 planetary carrier group
Notice: Collect the gear oil with clean
container, and check the oil for wear powder.

5. Disassembly of No. 1 planetary carrier group.

Notice: It is not required to disassemble
No. 1 steering carrier further hereto, so please
check the components in accordance with the
guidance mentioned by maintenance criteria.
6. Lift the gear ring (202) and remove it.
7. Remove No. 2 sun gear.
8. Remove No. 2 planetary carrier group.
 7-225
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.16 Disassembly and Assembly of the Swing Motor & Reduction Gear

Figures Procedure
9. Disassembly of No. 2 planetary carrier group.
Notice: It is not required to disassemble
No.2 planetary carrier group hereto.
Check the components carefully in accordance
with the guidance mentioned by maintenance
criteria. We recommend to replace No.2 planetary
carrier group in set as possible as you can. But if
the replacement of some part is inevitable, please
LG922E930E07441 operate in accordance with the following steps.
a. Remove the innermost spring pin (910) and
No. 2 spring pin (282).
b. Remove No.2 planetary gear (203) from the
side.
10. Remove spring backup ring (913) from drive
shaft (201).
Notice: Mark the gear and pin to avoid
mistake during the installation.
Notice: If No.2 spring pin (282) is removed,
never reuse it.
7-226
7.5 Hydraulic System December 30, 2017
7.5.16 Disassembly and Assembly of the Swing Motor & Reduction Gear CLG930E/936E

Figures Procedure
11. Place the reduction gear erectly. Support the
periphery of housing, make the drive shaft
surface downward, and knock the center of
shaft with plastic hammer to remove the shaft
from the housing.
Notice: Hereto, check the drive shaft, and
if there is no abnormality, it is not required to
disassemble it further.
Check the components carefully in accordance
with the guidance mentioned by maintenance
criteria. We recommend to replace in set as
possible as you can. But if the replacement of
some part is inevitable, please operate in
accordance with the following steps.
12. As it is shown in the figure, remove bearing
seal ring (915) and the bearing (401) from the
drive shaft bearing.
13. Remove the oil seal (401) from the housing
(102).
Notice: While removing the drive shaft,
protect it from being damaged.
Notice: If the bearing seal (915) and oil
seal (801) are removed, never reuse them.

Assembly

The chapter introduces the assembly of swing motor & reduction gear in two parts, including:
1. Assembly of swing motor
2. Assembly of reduction gear
 7-227
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.16 Disassembly and Assembly of the Swing Motor & Reduction Gear

Assembly sequence is in the reverse order of the removal.

1. Protect the components from being damaged.

2. Before the assembly, please check each component in accordance with maintenance criteria.

3. Each component shall be cleaned with detergent and then blow it dry with compressed air.

4. Before the assembly, revolving junction part and bearing, etc. must be applied with clean
working oil.

5. Seals such as O-ring and oil seal shall be replaced in principle.

6. Tighten the captive bolts and oil drain plug, etc. with torque wrench according to the
tightening torque shown in the following table.

If the liquid filling material is used. Peel the surface of the component with knife or similar
objects. and grind the surface with oil stone.

Table of specification and tightening torque of bolt

Tightening torque: N- Applicable part

Bolt size Name
m number
M20 Hexagon socket bolt 431 401

M33xP1.5 Pressure reducing valve 177 051

M30xP1.5 ROMH oil drain plug 334 469

PF1/4 ROM oil drain plug 36 467

12mm Hexagon socket bolt 102N-m 602

10mm Plug 65N-m 901

If it does not conform to the above part number, please refer to the assembly profile view.
7-228
7.5 Hydraulic System December 30, 2017
7.5.16 Disassembly and Assembly of the Swing Motor & Reduction Gear CLG930E/936E

Assembly of swing motor

Figures Procedure
1. Place the motor body (301) on the platform
suitable for operation with one side of the valve
body (303) upwards.
2. (This step can not be executed until the
cylindrical roller bearing is removed).
Install the inner ring of cylindrical roller bearing
(443) into the drive shaft (101) in the shrink-on
method.
Notice: Pay attention to the direction of
dowel pin of cylindrical roller bearing.
3. Install the inner ring of cylindrical roller bearing
(444) into the drive shaft (101) in the shrink-on
method.
4. Install the oil seal (491) in the motor body (301)
with tool.
Notice: Pay attention to the direction of oil
seal.
(Refer to the assembly profile view.)
Apply a thin layer of grease on the sealing part of
oil seal.
Notice: Knock it uniformly to protect the
periphery from being damaged.
One side of the output shaft

5. Knock it gently with hammer and steel bar to

install the cylindrical roller bearing (443) on the
motor body (301).
 7-229
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.16 Disassembly and Assembly of the Swing Motor & Reduction Gear

Figures Procedure
6. Install the drive shaft on the motor body (301).
Notice: Install it carefully to protect the
sealing part of oil seal from being damaged.
Notice: Twine the spline of shaft with
plastic adhesive tape.

7. Place the motor body (301) flatly, and then

insert the plunger (124).
Notice: Revolve the side with big chamfer
of plunger into the motor body.
Notice: Apply a layer of grease on it in
order to avoid it falling off from the junction
surface.

8. Assemble the plate (123) and plate spring, and

then assemble them and piston group (121,
122).
7-230
7.5 Hydraulic System December 30, 2017
7.5.16 Disassembly and Assembly of the Swing Motor & Reduction Gear CLG930E/936E

Figures Procedure
9. Install the plunger group (121, 122) assembled
on plate (123) on the cylinder (111), and install
it together with drive shaft (101) cooperatively.
 7-231
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.16 Disassembly and Assembly of the Swing Motor & Reduction Gear

Figures Procedure
10. Reset the motor body (301) with the oil seal
downward, and then install separator metal
plate (743) and friction plate (742) into the
motor body (301) in sequence.
Install 4 separator metal plates and 3 friction plate
in total.

11. Install O-ring (706) (707) in the motor body

(301).
Notice: The O-ring is uneasy to be broken
off when it is installed on the brake plunger if it
is applied a layer of grease.
7-232
7.5 Hydraulic System December 30, 2017
7.5.16 Disassembly and Assembly of the Swing Motor & Reduction Gear CLG930E/936E

Figures Procedure
12. Install the brake plunger (702) in the motor
body (301).

13. Install brake spring (712) in brake plunger

(702).

14. (This step can be implemented only when

removing cylindrical roller bearing (444).
Install the outer ring of the cylindrical roller bearing
(444) into valve body (303) while knock it gently
with hammer and steel bar.
Notice: Knock on the periphery of outer
ring evenly till it is completely installed into
clamp slot of valve body.
 7-233
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.16 Disassembly and Assembly of the Swing Motor & Reduction Gear

Figures Procedure
15. Install valve plate (131) into valve body (303),
and then into O-ring.
Notice: Apply a thin layer of grease on
joint surface of valve plate. (Prevent falling off)

16. Install valve body (303) on motor body (301),

and then tighten it with hexagon socket bolt.
Notice: Pay attention to installation
direction of valve body. (Refer to external
dimension figure)
Notice: Pay attention to avoiding falling-
off of valve plate.
Notice: Pay attention to avoiding falling-
down of brake spring.
Notice: Hexagon socket bolt shall be
tightened evenly.
7-234
7.5 Hydraulic System December 30, 2017
7.5.16 Disassembly and Assembly of the Swing Motor & Reduction Gear CLG930E/936E

Figures Procedure
17. Install plunger (351) and spring (355) into valve
body (303), and then install ROMH oil drain
plug (469) equipped with O-ring (488) into
valve body (303).
Notice: Check whether the plunger moves
smoothly.

18. Install pressure-reducing valve (051) into valve

body (303).
 7-235
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.16 Disassembly and Assembly of the Swing Motor & Reduction Gear

Assembly of reduction gear

Figures Procedure
1. Assembling the drive shaft assembly
a. Install bearing seal (915) into drive shaft
(201).
b. Apply the grease inside of bearing (401),
and press it into drive shat.
Notice: Before assembly, apply the grease
on both sides of bearing.

c. Apply the grease on the bearing.

7-236
7.5 Hydraulic System December 30, 2017
7.5.16 Disassembly and Assembly of the Swing Motor & Reduction Gear CLG930E/936E

Figures Procedure

2. Place the housing (102) on horizontal

operation platform
3. Install oil seal (801) in front of housing (102)
with the clamp.
4. Lift up drive shaft assembly with threaded hole
in front end of drive shaft, and then install it into
housing.
Notice: Apply seal(LOCKTITENO.222) on
the outer surface
Notice: Do not install forcibly, and do not
damage the lip of oil seal carefully with the
clamp in 5.3.4.
 7-237
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.16 Disassembly and Assembly of the Swing Motor & Reduction Gear

Figures Procedure
5. Lift the reduction gear erectly, and make drive
shaft downward.
6. Install the bearing with clamp (402).
7. Install the circlip (913).
8. Fill the grease into housing from grease filler.
Notice: Test the installation depth of drive
shaft from bearing surface with the clamp
according to the requirements in 5.3.4.
7-238
7.5 Hydraulic System December 30, 2017
7.5.16 Disassembly and Assembly of the Swing Motor & Reduction Gear CLG930E/936E

Figures Procedure
9. Install No. 2 planetary carrier group.
a. Install thrust washer (286).
b. Insert planetary gear (203).
c. Gently knock No. 2 pin (282) into planetary
gear with plastic hammer.

d. Install spring pin (910) into No. 2 planetary

carrier group (230), and knock on two ends
of spring pin tightly. Please refer to
installation essentials
 7-239
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.16 Disassembly and Assembly of the Swing Motor & Reduction Gear

Figures Procedure
10. Apply liquid seal on the joint surface of housing
(102).
11. Install No. 2 planetary gear group into housing
(102).
7-240
7.5 Hydraulic System December 30, 2017
7.5.16 Disassembly and Assembly of the Swing Motor & Reduction Gear CLG930E/936E

Figures Procedure
12. Install gear ring (202) into housing (102).
Fix gear ring with four screws temporarily, and pay
attention to using washer when screwing, in case
of damage the housing.
13. Install No. 1 planetary carrier group.
 7-241
December 30, 2017 7.5 Hydraulic System
CLG930E/936E 7.5.16 Disassembly and Assembly of the Swing Motor & Reduction Gear

Figures Procedure
14. Install No.1 sun gear (211)
15. Temporarily remove the bolt, and apply liquid
seal on the installation surface of housing
(102).
16. Install rear housing (104) to gear ring (202),
and tighten hex bolt.
17. Fill gear oil into reduction gear from the filler,
temporarily install the dipstick, and test gear oil
capacity.
7-242
7.6 Work Implement December 30, 2017
7.6.1 Removal and Installation of the Bucket CLG930E/936E

7.6 Work Implement

7.6.1 Removal and Installation of the Bucket

Removal

Figures Procedure
1. Start up the engine, operate the machine to
make bucket back lie on the ground, and then
shutdown the engine;
Notice: Place a pad between the bucket
and ground.

2. Remove captive bolt and nut (1);

3. Remove captive bolt and nut (2);
 7-243
December 30, 2017 7.6 Work Implement
CLG930E/936E 7.6.1 Removal and Installation of the Bucket

Figures Procedure
4. Remove the pin shaft (3) with copper hammer
and raping bar;
Notice: It needs the cooperation of two
people, one person hammers the pin shaft out
of pin hole from one end of the pin shaft with
copper hammer and raping bar, and the other
person holds the pin shaft on the other end.
Notice: O-ring, which is installed between
front bracket of arm and the bucket, needs to
be removed and put at a safe place.

5. Remove the pin shaft (4) with copper hammer

and raping bar;
Notice: It needs the cooperation of two
people, one person hammers the pin shaft out
of pin hole from one end of the pin shaft with
copper hammer and raping bar, and the other
person holds the pin shaft on the other end.
Notice: O-ring, which is installed between
front bracket of arm and the bucket, needs to
be removed and put at a safe place.

6. Start the engine, lift and swing the boom, and

then remove the bucket (5).
7-244
7.6 Work Implement December 30, 2017
7.6.1 Removal and Installation of the Bucket CLG930E/936E

Installation

Installation sequence is just reverse to the removal sequence.

Tightening torque of captive bolts (2) and (4) of the pin, M20: 600±55Nm, and the distance between
sleeve and its nearest nut is 1-1.5mm.
Clean up the thread part of bolt and nut before assembling the bolt, and apply the anaerobic thread
locker (Tonsan 1277) on thread surface.
Clean up the pin hole and pin shaft surface before installation.
If it is difficult to knock the pin shaft, adjust the installation position of the bucket and knock it again.
Do not damage or lose O-ring and dust ring during installation.
Refill the grease after the installation.
 7-245
December 30, 2017 7.6 Work Implement
CLG930E/936E 7.6.2 Removal and Installation of Link and Lever

7.6.2 Removal and Installation of Link and Lever

Removal

Figures Procedure
1. Remove the bucket. See "the Removal and
Installation of Bucket for details".
2. Retract arm cylinder completely, retract boom
cylinder to make work implement drop until the
front bracket of arm falls onto the ground,
select proper state to place sleeper between
link and arm as well as between bucket
cylinder body and arm during the process.

3. Remove captive bolt and nut (1);

4. Remove captive bolt and nut (2);

5. Install the rapping bar into axle hole of the link,

hook two ends of rapping rod with the sling,
and lift the link to vertical state with hoisting
equipment and sling.
6. Remove left lever (3).
Notice: There are adjusting washers
between the lever and link, and between the
lever and middle bracket of the arm, and it is
necessary to remove and put them at a safe
place.
7-246
7.6 Work Implement December 30, 2017
7.6.2 Removal and Installation of Link and Lever CLG930E/936E

Figures Procedure
7. Place a sleeper between right lever and arm,
knock on small end of the pin shaft (4) with
copper hammer and rapping bar, push the pin
shaft (4) to right lever, and remove the pin shaft
(4).
Notice: There are adjusting washers
between bucket cylinder and link, and between
the link and lever, and it is necessary to
remove and put them in a safe place.
8. Tighten the piston rod and the cylinder body
with wire rope.

9. Rotate right lever (5) and drop its end on the

ground, and take off the sleeper. Knock small
end of the pin shaft (6) with cooper hammer
and rapping rod, push the pin shaft (6) to the
direction of right lever, and remove the pin
shaft (6) and right lever (5) at the same time.
Notice: There are adjusting washers
between the lever and middle bracket of the
arm, and it is necessary to remove and put
them in a safe place.

10. Remove the link (7), and convey it to safe

place for storage.
 7-247
December 30, 2017 7.6 Work Implement
CLG930E/936E 7.6.2 Removal and Installation of Link and Lever

Installation

Installation sequence is just reverse to the removal sequence.

Tightening torque of captive bolts (1) and (4) of the pin: M20: 600±55Nm, and the distance between
sleeve and its nearest nut is 1-1.5mm.
Clean up the thread part of bolt and nut before assembling the bolt, and apply the anaerobic thread
locker (Tonsan 1277) on thread surface.
Clean up the pin hole and pin shaft surface before installation.
If it's difficult to knock in the pin shaft, adjust the mounting position of the lever and link, and knock it
again.
Do not damage or lose dust ring and adjusting shim during the installation.
Refill the grease after the installation.
7-248
7.6 Work Implement December 30, 2017
7.6.3 Removal and Installation of Arm CLG930E/936E

7.6.3 Removal and Installation of Arm

Removal

Before removal of oil pipe, open the arm and bucket completely, keep the distance between the
bucket and the ground about 300~400mm, shut down the engine, operate the lever to relieve
pressure, release the pressure of the accumulator, and loosen the hydraulic oil tank cover slowly
to release the pressure in the hydraulic oil tank.

Figures Procedure
11. Remove the bucket. See the Removal and
Installation of Bucket for details in this chapter;
12. Remove link and lever. See "Removal and
Installation of Link and Lever for details in this
chapter".
13. Remove the bucket cylinder. See "Removal
and Installation of Bucket Cylinder for details"
14. Start the engine, stretch the arm cylinder to the
most, operate boom cylinder, and put down
work implement to make front bracket of the
arm fall on the ground.
Notice: The pad needs to be placed
between the arm and ground.
15. Lift up arm cylinder with lifting rope and
hoisting equipment.
16. Remove the bolt, nut and plate (1) with
spanner.
17. Remove the pin shaft (2) with copper hammer
and rapping rod.
Notice: There is adjusting washer between
arm cylinder and arm, and it needs to take it
down and place it at a safe place.
18. Start the engine, retract arm cylinder piston
rod, and fasten piston rod with wire rope in
case of stretching out.
Notice: Do not release the pressure
19. Lift arm cylinder to certain space with hoisting
equipment, place the sleeper between arm
cylinder body and the boom, and put arm
cylinder on the sleeper.
 7-249
December 30, 2017 7.6 Work Implement
CLG930E/936E 7.6.3 Removal and Installation of Arm

Figures Procedure
20. Remove lifting rope on the cylinder.
21. 1 Install the pin (2) into pin hole, and lift the arm
(5) with lifting rope and equipment through the
pin (2).
22. 1 Remove captive bolt, nut and plate (3) of
boom bracket hinge pin.
23. Remove hinge pin shaft (4) with copper
hammer and rapping rod.
24. Slowly put the bucket arm on the ground with
the sling.
Notice: The sleeper needs to be placed
between the arm and ground.
25. Start the engine, and lift and swing the boom to
remove the arm.

Installation

Installation sequence is just reverse to the removal sequence.

The tightening torque of pin shaft captive bolts:
M12: 120±10Nm
M20: 600±55Nm
Clean up the thread part of bolt and nut before assembling the bolt, and apply the anaerobic thread
locker (Tonsan 1277) on thread surface.
Clean up the pin hole and pin shaft surface before installation.
If it's difficult to knock in the pin shaft, adjust the mounting position of the lever and link, and knock it
again.
Do not damage or lose dust ring and adjusting shim during the installation.
Refill the grease after the installation.
7-250
7.6 Work Implement December 30, 2017
7.6.4 Removal and Installation of the Boom CLG930E/936E

7.6.4 Removal and Installation of the Boom

Removal

Before removal of oil pipe, open the arm and bucket completely, keep the distance between the
bucket and the ground about 300~400mm, shut down the engine, operate the lever to relieve
pressure, release the pressure of the accumulator, and loosen the hydraulic oil tank cover slowly
to release the pressure in the hydraulic oil tank.

Clean the periphery of the assembled oil port before removing lines and fittings.
Seal the lines, fittings or hoses with plugs or caps when they are in disassembling state, so as to
prevent pollution source from entering the hydraulic system.

Figures Procedure
1. Start the engine, operate the machine to make
arm cylinder and bucket cylinder stretch out,
and operate boom cylinder to make the lever
fall on ground.
2. Release residual pressure in hydraulic oil line.
(See "Test and Adjustment" for release of
residual pressure in hydraulic oil line)
 7-251
December 30, 2017 7.6 Work Implement
CLG930E/936E 7.6.4 Removal and Installation of the Boom

Figures Procedure
3. Remove hydraulic hose (1) on both ends of
bucket cylinder with inner hexagon spanner,
and pay attention to wrapping the connector
with towel or cloth to prevent oil splashing.
Fasten the hose on boom tube with the strap
Notice: Hold hydraulic oil leaked from the
line with oil bucket to prevent contaminating
the ground.

4. Refer to "removal and installation of the arm" in

this chapter for removal of arm assembly (2),
(arm assembly includes arm, bucket, link,
lever, bucket cylinder and pin shaft)
Notice: The sleeper needs to be placed
between arm and ground.
5. Start the engine, and swing the machine till
there is enough space for removing the boom.
7-252
7.6 Work Implement December 30, 2017
7.6.4 Removal and Installation of the Boom CLG930E/936E

Figures Procedure
6. Operate the machine to place the boom on the
ground.
Notice: The pad needs to be placed
between front bracket of the boom and ground.

7. Disconnect the connection of grease line (3)

and boom cylinder.
8. Remove fixed sleeve (4) between boom
cylinder and boom hinge pin and its accessory
bolt and pin shaft.
Notice: There is adjusting washer
between locating sleeve and cylinder, and it
needs to take it down and place it at a safe
place.
9. Remove the fixed sleeve, bolt and nut on the
right side of boom cylinder with the method in
article 8.

10. Lift the left boom cylinder (5) with lifting rope
and equipment.
11. Push boom cylinder and hinge pin shaft (6) of
boom to the position that does not affect the
moving of boom cylinder (5) with copper
hammer and rapping rod.
 7-253
December 30, 2017 7.6 Work Implement
CLG930E/936E 7.6.4 Removal and Installation of the Boom

Figures Procedure
12. Start the engine, retract piston rod of left boom
cylinder, and fasten piston rod with wire rope to
prevent it stretching out. Lower left boom
cylinder to revolving frame, and place the
sleeper between the cylinder and frame.
13. Lower the right boom cylinder (7) with the
same method.
14. Lift the stretching part on both ends of boom
middle bracket pin shaft with lifting rope and
equipment.

15. Release residual pressure in hydraulic oil line.

(See "Test and Adjustment" for release of
residual pressure in hydraulic oil line)
16. Disconnect the harness (8) and fix it on the
boom with strap.
17. Disconnect the connection between hose (9)
and boom tube.
Notice: Wrap the connector with towel or
cloth to prevent oil splashing.
Notice: Hold hydraulic oil leaked from
the line with oil-holding equipment to
prevent the contamination.

18. Remove fixed plate (10) of boom and frame

hinge pin and its bolt and washer.
7-254
7.6 Work Implement December 30, 2017
7.6.4 Removal and Installation of the Boom CLG930E/936E

Figures Procedure
19. Remove boom and frame hinge pin (11) with
special tools.
20. Operate hoisting equipment to remove the
boom.

Installation

Installation sequence is just reverse to the removal sequence.

The tightening torque of pin shaft captive bolts:
M12: 120±10Nm
M20: 600±55Nm
The distance between the locating sleeve and its nearest nut is 1~1.5mm.
Clean up the thread part of bolt and nut before assembling the bolt, and apply the anaerobic thread
locker (Tonsan 1277) on thread surface.
The distance between the locating sleeve and its nearest nut is 1~1.5mm.
Clean up the pin hole and pin shaft surface before installation.
If it's difficult to knock in the pin shaft, adjust the mounting position of the lever and link, and knock it
again.
Do not damage or lose dust ring and adjusting shim during the installation.
Refill the grease after the installation.
 7-255
December 30, 2017 7.6 Work Implement
CLG930E/936E 7.6.5 Removal and Installation of the Work Implement Assembly

7.6.5 Removal and Installation of the Work Implement Assembly

Removal

Figures Procedure
1. Remove the bucket. See the Removal and
Installation of Bucket for details in this chapter;
2. Start up the engine, operate the machine to
retract arm cylinder and bucket cylinder
completely, and operate boom cylinder to make
work implement fall on the ground.

3. Remove fixed sleeve (1) between boom

cylinder and boom hinge pin and its accessory
bolt and pin shaft.
Notice: There is adjusting washer
between locating sleeve and cylinder, and it
needs to take it down and place it at a safe
place.
4. Remove the fixed sleeve, bolt and nut on the
right side of boom cylinder with the method in
article 3.

5. Lift the left boom cylinder (2) with lifting rope

and equipment.
6. Push boom cylinder and hinge pin shaft (3) of
boom to the position that does not affect the
moving of left boom cylinder (2) with copper
hammer and rapping rod.
7. Start the engine, retract piston rod of left boom
cylinder, and fasten piston rod with wire rope to
prevent it stretching out. Lower left boom
cylinder to revolving frame, and place the
sleeper between the cylinder and frame.
8. Lower the right boom cylinder (4) with the
same method
7-256
7.6 Work Implement December 30, 2017
7.6.5 Removal and Installation of the Work Implement Assembly CLG930E/936E

Figures Procedure
9. Release residual pressure in hydraulic oil line.
(See "Test and Adjustment" for release of
residual pressure in hydraulic oil line)
10. Disconnect the harness (8) and fix it on the
boom with strap.
11. Disconnect the connection between hose (9)
and boom tube.
Notice: Wrap the connector with towel or
cloth to prevent oil splashing.
Notice: Hold hydraulic oil leaked from
the line with oil-holding equipment to
prevent the contamination.

12. Remove fixed plate (7) of boom and frame

hinge pin and its bolt and washer.
 7-257
December 30, 2017 7.6 Work Implement
CLG930E/936E 7.6.5 Removal and Installation of the Work Implement Assembly

Figures Procedure
13. Remove the boom and frame hinge pin (8) with
special tools (9).

14. Install front bracket pin shaft of bucket arm

back into its front bracket.
15. Use two sets of hoisting equipment for
coordination, one lifts stretching part on both
ends of boom bracket pin, the other lifts
stretching part of arm bracket pin, and operate
two sets of hoisting equipment to remove work
implement assembly (10).

Installation

Installation sequence is just reverse to the removal sequence.

The tightening torque of pin shaft captive bolts: M12: 120±10Nm; M20: 600±55Nm
The distance between the locating sleeve and its nearest nut is 1~1.5mm.
Clean up the thread part of bolt and nut before assembling the bolt, and apply the anaerobic thread
locker (Tonsan 1277) on thread surface.
The distance between the locating sleeve and its nearest nut is 1~1.5mm.
Clean up the pin hole and pin shaft surface before installation.
If it's difficult to knock in the pin shaft, adjust the mounting position of the lever and link, and knock it
again.
Do not damage or lose dust ring and adjusting shim during the installation.
Refill the grease after the installation.
7-258
7.6 Work Implement December 30, 2017
7.6.6 Removal and Installation of Bucket Cylinder Assembly CLG930E/936E

7.6.6 Removal and Installation of Bucket Cylinder Assembly

Removal

Before removing hydraulic lines, lower the work implement to the ground completely, shut down
the engine, screw the key to the KEYON position, operate all hydraulic control levers several
times to release the residual pressure from the hydraulic system, and then loosen the hydraulic
oil tank cover to release the internal pressure from the oil tank.

Before removing the lines, fittings or hoses, make the marks so as to prevent wrong installation
while restoring. Clean the periphery of the assembled oil port as required, and put a drip pan to
receive oil.
Seal the lines, fittings or hoses with plugs or caps when they are in disassembling state, so as to
prevent pollution source from entering the hydraulic system.

Use lifting points as many as possible. Lifting ring is not allowed to bear shear force, and if there
is no appropriate lifting point, a wide lifting rope that is able to bear enough weight shall be used.

Figures Procedure
1. Referring to "the removal and installation of
bucket" & "the removal and installation of link
and lever" in this chapter, remove the bucket,
link and lever.
2. Operate the machine to lower arm end to the
ground.
Notice: Separate the cylinder from the arm
with tie, and avoid direct touch and bump to
cause appearance wear.
 7-259
December 30, 2017 7.6 Work Implement
CLG930E/936E 7.6.6 Removal and Installation of Bucket Cylinder Assembly

Figures Procedure
3. Retract bucket cylinder, and fix piston rod with
wire rope to prevent it from stretching out.

4. Disconnect hydraulic hose (1) on both ends of

bucket cylinder.
Notice: Wrap the joint with towel or cloth
to prevent oil splashing.
5. Remove the captive bolt of bucket cylinder pin
plate, and take down the plate (2).

6. Lift bucket cylinder with strap and hoisting

equipment.
Notice: Fix piston rod in the shortest and
safe state, and then lift it.
7-260
7.6 Work Implement December 30, 2017
7.6.6 Removal and Installation of Bucket Cylinder Assembly CLG930E/936E

Figures Procedure
7. Knock the little end of pin with copper bar and
take it out.
Do not stand at receding side of the pin shaft;
otherwise the sudden falling of the pin shaft will
cause personal injury.
8. Take down bucket cylinder and horizontally
place it on the sleeper.

Installation

Welding is not allowed on the cylinder, and the cylinder can not be ground wire for welding, in case the
parts may be damaged due to electric arcs produced between piston rod and cylinder head, and
between piston and cylinder body.
Installation sequence is just reverse to the removal
The tightening torque of pin shaft captive bolts: M12: 120±10Nm.
Clean the threaded hole before installation, and apply anaerobic thread locker (Tonsan 1277) on thread
surface.
 7-261
December 30, 2017 7.6 Work Implement
CLG930E/936E 7.6.6 Removal and Installation of Bucket Cylinder Assembly

Tightening torque of the oil pipe flange captive bolt: M10: 73.5±3.5Nm;

1. Clean up the pin hole and pin shaft surface before installation.

2. If it is difficult to knock the pin shaft, adjust the installation position of the bucket and knock it
again.

3. Protect the seal ring from being damaged during the installation.

4. Refill the grease after the installation.

5. Check the surface of piston rod, and it is not allowed to have tape, paint, concrete, etc. to
adhere on the surface of piston rod in case of damaging seal ring during action.

6. Any dirt is not allowed to enter into hydraulic system during removal and installation of
hydraulic cylinder. Oil port must be sealed in a reliable method. Such as rubber cap or sealing
plug

7. Hydraulic cylinder shall not bear abnormal stress after installation, and be guaranteed not to
bear unnecessary load. Otherwise, this will affect service life of cylinder.
7-262
7.6 Work Implement December 30, 2017
7.6.7 Removal and Installation of Arm Cylinder Assembly CLG930E/936E

7.6.7 Removal and Installation of Arm Cylinder Assembly

Removal

Before removing hydraulic lines, lower the work implement to the ground completely, shut down
the engine, screw the key to the KEYON position, operate all hydraulic control levers several
times to release the residual pressure from the hydraulic system, and then loosen the hydraulic
oil tank cover to release the internal pressure from the oil tank.

Before removing the lines, fittings or hoses, make the marks so as to prevent wrong installation
while restoring. Clean the periphery of the assembled oil port as required, and put a drip pan to
receive oil.
Seal the lines, fittings or hoses with plugs or caps when they are in disassembling state, so as to
prevent pollution source from entering the hydraulic system.

Use lifting points as many as possible. Lifting ring is not allowed to bear shear force, and if there
is no appropriate lifting point, a wide lifting rope that is able to bear enough weight shall be used.

Figures Procedure
1. Lift the arm cylinder steadily with nylon strap
and hoisting equipment.
 7-263
December 30, 2017 7.6 Work Implement
CLG930E/936E 7.6.7 Removal and Installation of Arm Cylinder Assembly

Figures Procedure
2. Remove captive bolt of piston rod pin, and
remove the plate (1).
3. Knock the little end of pin with copper bar and
take it out.
Notice: Do not stand at receding side of
the pin shaft; otherwise the sudden falling of
the pin shaft will cause personal injury.

4. Operate the machine to retract the arm bucket

piston rod completely, and fix piston rod with
wire rope to prevent it stretching out.
Notice: Be sure to fix piston rod in the
shortest and safe state, and then lift it.

5. Remove two hydraulic hoses (2) with arm

cylinder.
6. Disconnect grease hose (3);
7. Remove captive bolt of piston rod pin, and
remove the plate (4).
7-264
7.6 Work Implement December 30, 2017
7.6.7 Removal and Installation of Arm Cylinder Assembly CLG930E/936E

Figures Procedure
8. Knock the little end of pin with copper bar and
take it out.
Notice: Do not stand at receding side of
the pin shaft; otherwise the sudden falling of
the pin shaft will cause personal injury.
9. Slowly lift arm cylinder and place it on the
sleeper.

Installation

Welding is not allowed on the cylinder, and the cylinder can not be ground wire for welding, in case the
parts may be damaged due to electric arcs produced between piston rod and cylinder head, and
between piston and cylinder body.
Installation sequence is just reverse to the removal
The tightening torque of pin shaft captive bolts: M12: 120±10Nm.
Clean the threaded hole before installation, and apply anaerobic thread locker (Tonsan 1277) on thread
surface.
 7-265
December 30, 2017 7.6 Work Implement
CLG930E/936E 7.6.7 Removal and Installation of Arm Cylinder Assembly

Tightening torque of the oil pipe flange captive bolt: M10: 73.5±3.5Nm.

1. Clean up the pin hole and pin shaft surface before installation.

2. If it is difficult to knock the pin shaft, adjust the installation position of the bucket and knock it
again.

3. Protect the seal ring from being damaged during the installation.

4. Refill the grease after the installation.

5. Check the surface of piston rod, and it is not allowed to have tape, paint, concrete, etc. to
adhere on the surface of piston rod in case of damaging seal ring during action.

6. Any dirt is not allowed to enter into hydraulic system during removal and installation of
hydraulic cylinder. Oil port must be sealed in a reliable method. Such as rubber cap or sealing
plug

7. Hydraulic cylinder shall not bear abnormal stress after installation, and be guaranteed not to
bear unnecessary load. Otherwise, this will affect service life of cylinder.
7-266
7.6 Work Implement December 30, 2017
7.6.8 Removal and Installation of Boom Cylinder Assembly CLG930E/936E

7.6.8 Removal and Installation of Boom Cylinder Assembly

Removal

Before removing hydraulic lines, lower the work implement to the ground completely, shut down
the engine, screw the key to the KEYON position, operate all hydraulic control levers several
times to release the residual pressure from the hydraulic system, and then loosen the hydraulic
oil tank cover to release the internal pressure from the oil tank.

Before removing the lines, fittings or hoses, make the marks so as to prevent wrong installation
while restoring. Clean the periphery of the assembled oil port as required, and put a drip pan to
receive oil.
Seal the lines, fittings or hoses with plugs or caps when they are in disassembling state, so as to
prevent pollution source from entering the hydraulic system.

Use lifting points as many as possible. Lifting ring is not allowed to bear shear force, and if there
is no appropriate lifting point, a wide lifting rope that is able to bear enough weight shall be used.

Figures Procedure
1. Fix the boom cylinder (1) with nylon sling and
travel crane.
 7-267
December 30, 2017 7.6 Work Implement
CLG930E/936E 7.6.8 Removal and Installation of Boom Cylinder Assembly

Figures Procedure
2. Remove the captive bolt of piston rod pin and
take down the sleeve (2).
3. Remove grease line (3).

4. Knock the little end of pin with copper bar and

take it out.
Notice: Do not stand at receding side of
the pin shaft; otherwise the sudden falling of
the pin shaft will cause personal injury.

5. Operate the excavator to retract boom cylinder

piston rod completely. Fix the piston rod with
wire rope to prevent it from stretching out.
Place a wood block under the boom cylinder so
as to lower the cylinder gently.
7-268
7.6 Work Implement December 30, 2017
7.6.8 Removal and Installation of Boom Cylinder Assembly CLG930E/936E

Figures Procedure
6. Disconnect hydraulic hose (4) of boom
cylinder.

7. Remove captive bolt of boom cylinder body

pin, and take pin plate out (5).
8. Remove boom cylinder body pin (6).

9. Lift the boom cylinder assembly out and place

it on dunnage.
Notice: Be sure to fix piston rod in the
shortest and safe state, and then lift it.
 7-269
December 30, 2017 7.6 Work Implement
CLG930E/936E 7.6.8 Removal and Installation of Boom Cylinder Assembly

Installation

Welding is not allowed on the cylinder, and the cylinder can not be ground wire for welding, in case the
parts may be damaged due to electric arcs produced between piston rod and cylinder head, and
between piston and cylinder body.
Installation sequence is just reverse to the removal
The tightening torque of pin shaft captive bolts: M12: 120±10Nm.
Clean the threaded hole before installation, and apply anaerobic thread locker (Tonsan 1277) on thread
surface.
Tightening torque of the oil pipe flange captive bolt: M10: 73.5±3.5Nm;

1. Clean up the pin hole and pin shaft surface before installation.

2. If it is difficult to knock the pin shaft, adjust the installation position of the bucket and knock it
again.

3. Protect the seal ring from being damaged during the installation.

4. Refill the grease after the installation.

5. Check the surface of piston rod, and it is not allowed to have tape, paint, concrete, etc. to
adhere on the surface of piston rod in case of damaging seal ring during action.

6. Any dirt is not allowed to enter into hydraulic system during removal and installation of
hydraulic cylinder. Oil port must be sealed in a reliable method. Such as rubber cap or sealing
plug

7. Hydraulic cylinder shall not bear abnormal stress after installation, and be guaranteed not to
bear unnecessary load. Otherwise, this will affect service life of cylinder.
7-270
7.6 Work Implement December 30, 2017
7.6.9 Disassembly and Assembly of Cylinder CLG930E/936E

7.6.9 Disassembly and Assembly of Cylinder

Method for disassembly and assembly of the cylinder introduced in the chapter is common approach of
excavator cylinder. Refer to the following figure for component names involved in the text. Different
cylinders may have some differences.

1. Piston rod 12.Press plate 22.O-ring 32.C-bushing

2. End cover 13.Oil ring 23.O-ring snap ring 33.Hex screw
3. Cylinder block group 14.Retainer 24.Buffer ring 34.O-ring
4. Cushion collar 15.Dust ring 25.Wiper ring 35.Bolt
5. Piston 16.Seal ring for shaft 26.Molding guide ring 36.Spring washer
6. Clip 17.Split washer 27.Seal ring for hole 37.Bolt
7. Rear cushion collar 18.Buffer ring 28.Flat end set screw 38.Spring washer
8. Check ring 19.Hex screw 29.Steel ball 39.Oil port cover
9. Oil pipe group A 20.Slide bushing 30.Buffer ring 40.Rubber gasket
10.Oil pipe group B 21.Steel wire snap ring 31.Dust ring 41.Hexagon socket bolt
11.Clamp group
 7-271
December 30, 2017 7.6 Work Implement
CLG930E/936E 7.6.9 Disassembly and Assembly of Cylinder

Disassembly

Preparations

1. Keep the operation area clean and tidy.

Fixed device
2. Estimate the total weight of the hydraulic
cylinder and accessories, prepare
appropriate lift equipment, and the hook
distribution shall keep the lifting stable.

The hydraulic cylinder oil ports shall be

sealed with the rubber plugs or seal plugs to
prevent the hydraulic cylinder from being
polluted by the foreign matters.
5. Fix the piston rod with the pin hole and the
flat part of piston rod lifting eye.

Protect the hydraulic cylinder assembly 6. Remove the piston nut.

(piston rod in particular) from damage. (1) Remove the setscrew.
1. Drain the oil from cylinder. There are two chisel seams at the outside of
setscrew; they’re used for riveting on the cushion
2. Fix the hydraulic cylinder.
head. Remove the riveting parts with hand drill,
(1) Remove the pipes and other interferences and then remove the setscrew.
before the fixation.
(2) Remove the steel ball from setscrew.
(2) Fix the hydraulic cylinder on the vertical or
(3) Remove the piston nut.
horizontal position.
(3) Locate with the pin shaft hole at the cylinder
bottom.
3. Remove the cover.
Thread type: remove by using hook-end wrench.
4. Pull out the piston rod
(1) Confirm that the pipes and so on have been
removed.
(2) Prepare the appliance to collect the hydraulic
oil from the hole of telescope side (the end
cover side).
(3) Pull out the piston rod to the longest position,
loosen and pull out the end cover slowly.
7. Remove the parts such as piston, etc.
(4) Pull out the piston rod with the end cover
together, and place them on the tie. Remove components according to the sequence:
Nuts→ Pistons → Cushion Collars → End
Covers.
7-272
7.6 Work Implement December 30, 2017
7.6.9 Disassembly and Assembly of Cylinder CLG930E/936E

8. Remove the cushion collars of telescope 11. Remove the dust ring and circlip
side.
(1) When removing the dust ring, put the screw
(1) Remove the piston nut. driver against the opening of the dust ring
circlip, knock it to the bottom of circlip, and
(2) Knock the elastic snap ring with plastic
then pry the circlip to take it out.
hammer or other tools to remove it without
damaging piston rod and cushion collar. (2) Continue to knock the screw driver until it
running through the whole dust ring, then tip
(3) Slide the cushion collar to the piston rod
and pry the entire dust ring for removing.
screw, and then the baffle rings (double-slice
type) fall off. 12. Remove the slide bushing.
(4) Remove the cushion collar. There is a gap on (1) Find the juncture of the slide bushing.
the buffer ring, then remove the buffer ring by
(2) Support the upper end of the slide bushing
using the gap.
opening with screw driver, and then knock on
9. Removal of piston seal. the screw driver with the hammer until it pass
through the whole slide bushing.
(1) The guide rings and wiper rings shall be
removed simply by hands. (3) Remove the entire slide bushing with screw
driver.
(2) Make the screw driver up-right with the seal
ring and knock it with hammer, then cut off 13. Remove the lifting eye dust ring and the
and remove it. bushing.
(3) Take out the O-ring with iron needle. (1) Remove the dust ring from the lifting eye
hole. Same as the removal of the cover dust
ring, remove it with screw driver or other
tools.
Thread
(2) Remove the bushing with the heel plate, as
shown in figure.
Piston rod

Snap ring Buffering Cushion Snap ring (2 Press

ring with collar slices)
one notch

Mounting
clamp
Bushing
10. Remove the end cover seal.
(1) Remove the primary seal: Put iron needle
against the upper edge of the seal ring and
extend the iron needle to the bottom of seal
ring groove, and run through the primary
sealing element, then tip and pry the entire
sealing element for removing.
(2) Remove the buffer ring: first remove the
buffer ring (black), and the following removal
is the same as the removal of primary seal.
 7-273
December 30, 2017 7.6 Work Implement
CLG930E/936E 7.6.9 Disassembly and Assembly of Cylinder

Installation Recheck the slide bushing for the scratch.

1. Install the lifting eye dust ring and bushing.

(1) Press it into the piston rod axle hole with the
mounting clamp. Do not scratch the slide bushing during the
(2) Install dust ring with the heel plate. assembly.

(3) Take out the O-ring backup ring from the

heating box and assemble it, press the
backup ring with iron needle, and rotate it for
Press one revolution around the ring recess to
transform it. Place the relevant O-ring into the
groove, install it with iron needle and rotate it
Mounting for one revolution to ensure that the
clamp
assembly is complete without turn-up.
Bushing
(4) Turn over the cover by 180°.
(5) Install the buffer ring into its groove.

Pay attention to the direction. Install the

small backup ring into the buffer ring, and
keep the circular side of the small snap ring
Heel block at the inner side.

Piston rod (6) Pay attention to the direction of the

primary seal ring, and install the snap ring
firstly if there’s primary seal snap ring.
Dust ring

Do not scratch the slide bushing during the

assembly.
Bushing
LG922E930E07534 (7) Apply adhesive to the outside area of the
dust ring, place it on the dust ring groove,
and then place the guide sleeve under the
2. Assembly of end cover parts. pressure head and press it.
(1) Press the slide bushing with the press-in (8) Erase redundant adhesive around the dust
clamp. ring with wiping paper, and then install the
(2) Install the round wire snap ring into the slide snap ring of dust ring into its groove.
bushing snap ring slot.
7-274
7.6 Work Implement December 30, 2017
7.6.9 Disassembly and Assembly of Cylinder CLG930E/936E

(9) Precautions about the installation of cover

sealing elements.

Dust ring and snap ring

Clamp

Main seal ring End

cover
Buffer ring and snap ring

Slide bushing

O-ring snap ring (white)

Slide
O-ring (Black) bushing

1. Forget to assemble or not

2. Whether the mounting position is
correct
3. Are there parts installed in wrong
direction?

Main seal ring

Do not confuse with Buffer ring and snap
Slide bushing
the snap ring ring
No damage on
Install the
the internal
buffer ring and
surface
then the snap
ring (pay
attention to the
direction)

Dust ring Snap ring O-ring and snap ring

Install to the bottom Install it in the groove.
Piston rod may be Snap
scratched if it slides out ring
from the groove.
No damage

O-ring
Qualified Fail Fail
O-ring Snap ring
protrudes sinks
upward downward
 7-275
December 30, 2017 7.6 Work Implement
CLG930E/936E 7.6.9 Disassembly and Assembly of Cylinder

3. Install the piston sealing elements.

4. Install the piston rod assembly.
(1) Install the black lining ring into the seal ring
(1) Fix the piston rod side.
groove of the piston with iron needle (prevent
the sealing elements from being scratched). (2) When installing the guide sleeve and piston
rod, the lip of the dust ring and the shaft ring
(2) Put the guide jig onto the piston.
shall not be hooked by the shoulder parts.
(3) Take out the primary seal ring from the According to the following figure to install the
heating box and install it to the interior guide guide sleeve and piston rod.
jig, and then place the exterior pressing
sleeve.
(4) Press the external sleeve by the compressor.
Press the seal ring into the groove, then
remove the sleeve and guide jig.
(5) Install snap ring of the seal ring for hole.

The chamfering side faces outward and the

two gaps of the snap ring are not on the same
direction.

(6) Both guide rings and wiper rings have

openings, open the openings in the minimum
limit, and then install them from the axial (3) For the piston rod with the front cushion
direction. collar, install the plane machining parts of the
cushion collar according to figure below.
Backrest block Please compress by
Please compress by
using a press
using a press
Jig Flat wire Cushion Piston
direction collar
Correct the
clamp

Jig

Piston

Seal ring
Seal ring

Snap ring

Front buffer
7-276
7.6 Work Implement December 30, 2017
7.6.9 Disassembly and Assembly of Cylinder CLG930E/936E

(4) For the piston rod with rear cushion collar, 6. Tighten the end cover
install relevant components and parts
Tighten it according to the required tightening
according to the following orders:
torque on the assembling drawing.
a. Install the gap direction of the buffer ring
(1) The thread type: tighten it with the hook
into the ring recess towards the thread
wrench.
side.
b. Install the facing process parts of the
cushion collar according to the following
figure.
Riveting Punch
c. Put the baffle ring (double-slice) into the
slip groove.
Set screw
d. Press the cushion collar towards the baffle
ring sufficiently, and then install the clip.
Knock it into the slip groove gently with Steel ball

hammer without damaging the piston rod

and cushion collar.

7. Install the tubing.

Thread
(1) Confirm whether the O-ring is installed into
Piston rod the groove correctly.
(2) Insert the oil tube into the connector and
tighten the nut.

Buffering ring Buffer bearing Snap ring (2

(3) Referring to the requirements of assembling
Clip
with notch bushing slices) drawing, adjust the position of the oil tube
and tighten the clamp.
(4) Tighten the fastening nut.

(5) Tighten the piston nut. 8. Test run.

(6) Install the setscrew and steel ball on nut. (1) Conduct full-stroke movement more than six
times slowly after the machine body is
After fastening piston nut, put steel ball in it, then installed to keep the hydraulic cylinder full of
tighten setscrew. Rivet two parts of the periphery oil.
with the cushion head.
(2) If the oil cylinder is filled with exhaust vents,
5. Install the piston rod into the cylinder body. try to pressurize the exhaust vent side (return
(1) Fix the cylinder body vertically or horizontally. side) to release the air.

(2) The vertical situation: install piston rod into

the cylinder body according to its dead-
weight.
(3) When the piston rod entering into the cylinder
body, protect the wiper ring and guide ring
from falling off.
 7-277
December 30, 2017 7.6 Work Implement
CLG930E/936E 7.6.9 Disassembly and Assembly of Cylinder

(3) Apply the grease or engine oil to the bushing

at both ends of the lifting eye.

Note O-ring
7-278
7.7 Air Conditioning System December 30, 2017
7.7.1 Removal and Installation of A/C Evaporator Assembly CLG930E/936E

7.7 Air Conditioning System

7.7.1 Removal and Installation of A/C Evaporator Assembly

Removal

Before the removal of the air compressor assembly, recycle the refrigerant in the A/C system by
using the refrigerant filling device, and ensure that there is no pressure in the A/C system, and
then remove it. During the recycle of the refrigerant, please wear the goggles correctly to prevent
personal injury.

During the removal and installation of pipe line, it is prohibited to wear cottony gloves, in order to
avoid the refrigerant leakage caused by the foreign matter adhesion on the O-ring position.
During the removal of the A/C warm water pipe, please use the special clamp or plug and seal the
water pipe port to protect the engine coolant from running off.
When the lines, connectors or hoses are in the disassembling state, shield them with plugs or
covers to prevent pollution sources from entering into the A/C system.

Figures Procedure
1. Remove six captive bolts (1) of bottom plate on
lower part of floor plate, and take down bottom
plate (2).
 7-279
December 30, 2017 7.7 Air Conditioning System
CLG930E/936E 7.7.1 Removal and Installation of A/C Evaporator Assembly

Figures Procedure
2. Disconnect the connector (3) connecting with
A/C high-low pressure switch.

3. Remove captive bolt (4) of A/C refrigerating

tube with spanner, and take down the fixed
plate (5). Move A/C refrigerating tubes (6) and
(7) out at the same time.

4. Remove fixed clamp (8) of A/C water pipe.

5. Pull the water pipes (9) and (10) out.
7-280
7.7 Air Conditioning System December 30, 2017
7.7.1 Removal and Installation of A/C Evaporator Assembly CLG930E/936E

Figures Procedure
6. Open access door on driving side with the key,
and take out air filter (11) outside air
conditioner.

7. Remove the fridge (12) and storage grid (13)

on the upper part of A/C hood in the cab.

8. Remove two captive bolts (14) and three

fastening screws (15) of A/C hood upper cover
and take down the upper cover (16).
 7-281
December 30, 2017 7.7 Air Conditioning System
CLG930E/936E 7.7.1 Removal and Installation of A/C Evaporator Assembly

Figures Procedure
9. Remove three bolts (17) from the lower cover
plate, and remove that plate (18).

10. Remove setscrew (19) of new air duct that has

butt joint with new vent of evaporator assembly
to extract new air duct (20) upward.

11. Remove the rear air ducts (21) and (22) on top
of evaporator assembly.
7-282
7.7 Air Conditioning System December 30, 2017
7.7.1 Removal and Installation of A/C Evaporator Assembly CLG930E/936E

Figures Procedure
12. Remove the four air ducts (23)(24)(25) at the
side of evaporator assembly.

13. Remove two captive bolts (26) of air duct guard

plate on front lower part of evaporator
assembly, and take down air duct guard plate
(27).

14. Push feet blow air duct (28) forward to

separate it from feet blow air duct of evaporator
assembly.

28
 7-283
December 30, 2017 7.7 Air Conditioning System
CLG930E/936E 7.7.1 Removal and Installation of A/C Evaporator Assembly

Figures Procedure
15. Remove the connectors (29) and (30)
connected with A/C harness and located on
29
rear part of evaporator assembly.

30

16. Remove seven captive bolts (31) of evaporator

assembly.
17. Move A/C evaporator assembly (32) away from
the floor.

32

31

Installation

The installation sequence is just opposite to the removal sequence.

Torque requirements for air conditioning refrigerating pipe joint at evaporator assembly side: M6,
10±2N.m.
After the installation of the A/C evaporator as, it needs to use the refrigerant filling equipment to
vacuumize the A/C system and fill it with refrigerant, and the refrigerant filling quantity is 950±50g.
Pay attention to the orientation when installing air filter outside the air conditioner, and the suede side of
evaporator should face inward.
7-284
7.7 Air Conditioning System December 30, 2017
7.7.2 Removal and Installation of A/C Compressor Assembly CLG930E/936E

7.7.2 Removal and Installation of A/C Compressor Assembly

Removal

Before the removal of the air compressor assembly, recycle the refrigerant in the A/C system by
using the refrigerant filling device, and ensure that there is no pressure in the A/C system, and
then remove it. During the recycle of the refrigerant, please wear the goggles correctly to prevent
personal injury.

During the removal and installation of pipe line, it is prohibited to wear cottony gloves, in order to
avoid the refrigerant leakage caused by the foreign matter adhesion on the O-ring position.
When the lines, connectors or hoses are in the disassembling state, shield them with plugs or
covers to prevent pollution sources from entering into the A/C system.

Figures Procedure
1. Remove 4 captive bolts (1) of diesel engine fan
guard. Move shield-lh of the fan (2).
 7-285
December 30, 2017 7.7 Air Conditioning System
CLG930E/936E 7.7.2 Removal and Installation of A/C Compressor Assembly

Figures Procedure
2. Unscrew locking bolt (3) of A/C belt tension
pulley.

3. Unscrew tension bolt (4) of A/C belt tension

pulley to removable position of A/C belt;
4. Move tension pulley along guide groove of
compressor bracket and take down A/C belt
(5).

5. Disconnect base machine harness connector

(6) mutually inserting with compressor clutch
connector.
7-286
7.7 Air Conditioning System December 30, 2017
7.7.2 Removal and Installation of A/C Compressor Assembly CLG930E/936E

Figures Procedure
6. Separately remove captive bolt (7) of A/C
refrigerating tube on the side of A/C
compressor, and move refrigerating tubes (8)
and (9) out.

7. Remove four captive bolts (10) of A/C

compressor with wrench, and take down A/C
compressor (11).
8. Weight of compressor assembly: 6Kg.

Installation

The installation sequence is just opposite to the removal sequence.

Adjust the pre-tightening force of the A/C compressor belt to 441±88.2N.
M6 bolt torque of connector: 10±2Nm.
Upon the assembly of the A/C compressor, it needs to use the refrigerant fill equipment to vacuumize the
A/C system and fill it with refrigerant, and the filling quantity of the refrigerant is 950±50g.
 7-287
December 30, 2017 7.8 Cab
CLG930E/936E 7.8.1 Removal and Installation of Cab

7.8 Cab

7.8.1 Removal and Installation of Cab

Removal

Please turn off power supply before removal.

Figures Procedure
1. Open the hood left rear door(1), shut down the
disconnect switch (2), remove the buttery
guard (3), remove the battery shield (4) from
the battery.

2. Remove the fridge (5), sundries box (6), upper

cover (7) and lower cover (8) behind the cab
and move them out;
3. Unlock two locks on rear cover (9), and take
down the cover.
7-288
7.8 Cab December 30, 2017
7.8.1 Removal and Installation of Cab CLG930E/936E

Figures Procedure
4. Remove 4 air ducts (11) connected with A/C
evaporator (10);

5. Disconnect the connector (12) on right rear

pillar of the cab.
6. Disconnect the connector (13);
7. Disconnect nine-pin plug (14), and pull its
harness out, and place on the floor;
8. Disconnect two connectors connected with
controller (15);
9. Unplug two relays (16) on A/C harness from
stop plate of the cab;
10. Disconnect two connectors (17) connected
with fuse box;
11. Remove two fixed clips (18);
12. Disconnect the connector (19) connecting
frame harness and A/C harness and located on
right side of evaporator (10);
13. Remove the antislip step (20);
14. Move floor mat out (21);
 7-289
December 30, 2017 7.8 Cab
CLG930E/936E 7.8.1 Removal and Installation of Cab

Figures Procedure
15. Remove decoration plate (22) installed on the
floor;
16. Remove the decoration (23);

17. Remove the captive bolt of the cover (24);

18. Disconnect the connector connected on sun
sensor (25), and pull out the harness
connecting the connector from the rear of the
cab, and place it on the evaporator.

19. Remove the 4 shock absorber bolts (26) on the

4 corners of the cab;
20. Remove the 6 bolts (27) connecting the cab
and floor plate and located on cab bottom
frame.
7-290
7.8 Cab December 30, 2017
7.8.1 Removal and Installation of Cab CLG930E/936E

Figures Procedure
21. Disconnect water pipe (28) on washing end of
wiper washer reservoir in the rear of the cab
from washer reservoir (29);
22. Remove the clamp (30) from fixed water pipe
(28);
23. Tidy water pipe (28) and fix on outer wall of the
cab, located at water pipe outlet on right rear
side of the cabin outside the cabin.

24. If equipped with cab with roll over protection

structure, it needs to remove the plate (29)
located below the cab.

25. If equipped with cab with roll over protection

structure, it needs to remove the pin (30)
located below cab rear end, and then remove
the nut (31) and take the plate (32) .
 7-291
December 30, 2017 7.8 Cab
CLG930E/936E 7.8.1 Removal and Installation of Cab

Figures Procedure
26. If equipped with cab with roll over protection
structure, it needs to remove the pin (33)
located below cab rear end, and then remove
the nut (34) and take the plate (35) .

27. If the cab is not equipped with falling-object

protective structure, install the 4 of M16 lifting
eye bolts (36) to the lifting hole (37) located at
top of cab, hook the two diagonal bolts with
sling (38) to remove the cab from the complete
machine.
28. Start hoisting equipment, and slowly lift the
cabin.
Notice: The weight of standard cab is
390kg; the weight of cab with roll over
protection structure is 580kg, please choose
the proper sling
Notice: Please be careful about the
operation, and during the lift, the water pipes
and harness shall not drag other components.
7-292
7.8 Cab December 30, 2017
7.8.1 Removal and Installation of Cab CLG930E/936E

Figures Procedure
29. If the cab is equipped with falling-object
protective structure, hook the circular tube
beam (40) of protective cover using sling (39);
30. Start hoisting equipment, and slowly lift the
cabin.
Notice: The cab weight is 680kg, so please
select applicable sling
Notice: please be careful about the
operation, and during the lift, the water pipes
and harness shall not drag other components.

Installation

The installation sequence is just opposite to the removal sequence.

Tightening torque of mounting bolt M12-10.9 of the cab: 120±10Nm;
Tightening torque of mounting nut M20- of shock absorber is: 600±50Nm;
Clean the threaded hole before installation, and apply anaerobic thread locker (Tonsan 1277) on thread
surface in order to avoid its looseness.
 7-293
December 30, 2017 7.8 Cab
CLG930E/936E 7.8.2 Removal and Installation of Floor Frame Assembly

7.8.2 Removal and Installation of Floor Frame Assembly

Removal

When removing the hose, mark on the hose and connectors to facilitate the matching when
assembling;
Seal up the removed connectors and hoses with covers or plugs to prevent water and dust, etc.;
Clean up the periphery of the assembled oil port.

Figures Procedure
1. Remove the cab. For specific operations, refer
to "Removal and Installation of Cab"
2. Remove the boot (1);
3. Remove two captive bolts (2) on front and rear
part of console upper cover (3) respectively;
4. Move console upper cover (3) upward, and
remove its internal electrical connectors;
5. Pull the harness out of left console;
6. By referring to above steps, pull the harness
out of right armrest.

7. Remove four clips (4) fixed on the floor;

8. Slide grommet (5) to the right off floor plate,
and move the harness (6) out of floor plate.
Notice: Wire harness (6) includes A/C
harness.
7-294
7.8 Cab December 30, 2017
7.8.2 Removal and Installation of Floor Frame Assembly CLG930E/936E

Figures Procedure
9. Remove the plate (7) and plate (8) on lower
part of the cab.

10. Disconnect two A/C water pipes (9) and

refrigerating tubes (10) located on lower part of
A/C evaporator assembly.

11. Disconnect 8 pilot pipes connectors (11)

located on the rear part of the cab,
12. Remove the clamps (12) and (13);
 7-295
December 30, 2017 7.8 Cab
CLG930E/936E 7.8.2 Removal and Installation of Floor Frame Assembly

Figures Procedure
13. Remove pilot clamp (14), clamp (15), clamp
(16) and bracket (18) at the bottom of floor
plate;
14. Disconnect 4 pilot lines (17);
15. Remove the 6 pilot pipe (19) connecting with
the foot pilot valve (20).
16. Arrange 12 pilot hydraulic lines stretching out
from inside of the cab, and ensure there is no
pulling phenomenon with other parts during
lifting process.

17. Install the 4 M12 lifting eye bolts (20) to the

lifting holes at 4 corners on the floor.
18. Hook the lifting eye bolts (20) with 4 hangers of
the sling (21).
19. Start lifting device, and slowly hang from floor
plate.
Notice: The bearing capacity of the sling
shall not be less than 300 KG.
Notice: Please be careful to operate, and
pay attention to not make the pilot pipes shall
drag other components during the lifting
process.

Installation

The installation sequence is just opposite to the removal sequence.

Tightening torque of mounting nut of cab shock absorber is 600±50 N.m; before assembly, clean the
threaded hole, and apply anaerobic thread locker (Tonsan 1277) on the thread to prevent the nut from
loosing.
7-296
7.8 Cab December 30, 2017
7.8.2 Removal and Installation of Floor Frame Assembly CLG930E/936E
 8-1
December 30, 2017 Attached drawing
CLG930E/936E

Attached drawing

8.1 Structure of Main Control Valve...............................................................................8-3

8.2 Hydraulic Schematic .................................................................................................8-5
8.3 Electrical Schematic Diagram ..................................................................................8-6
8.4 A/C Schematic Diagram ............................................................................................8-7
8-2
Attached drawing December 30, 2017
CLG930E/936E
 8-3
December 30, 2017 8.1 Structure of Main Control Valve
CLG930E/936E

8.1 Structure of Main Control Valve

8-4
8.1 Structure of Main Control Valve December 30, 2017
CLG930E/936E
 8-5
December 30, 2017 8.2 Hydraulic Schematic
CLG930E/936E

8.2 Hydraulic Schematic

8-6
8.3 Electrical Schematic Diagram December 30, 2017
CLG930E/936E

8.3 Electrical Schematic Diagram

. . . . .
 8-7
December 30, 2017 8.4 A/C Schematic Diagram
CLG930E/936E

8.4 A/C Schematic Diagram

$03  +9$& 6*
 30 
 
      

$03  $03 

 3)  3)

   
          % % % % % % % % $ $ $ $ $ $ $ $ $

% % % % % % % % % % $ $ $ $ $ $ $ $

0
 0

7+


0  30

 7+
0 


 3

  

LG922E930E08003
8-8
8.4 A/C Schematic Diagram December 30, 2017
CLG930E/936E
 Statement

Part of copyrights reserved by Cummins Co.,Ltd.

Any reproduction shall be used for specific purpose with
permission of Cummins.
It is forbidden to use and/or reproduce the document without
permission of Cummins.
1-4
December 30, 2017
CLG930E/936E