Service Manual of RS8160 Road Roller

SERVICE MANUAL

Version:0210

2 Engine System
 Service Manual forLG936L Wheel Loader

CONTENTS
2 Engine System ..................................................................................................... 2-1
21 General................................................................................................................. 2-1
211 Engine Description ...................................................................................... 2-1
212 Engine Identification ................................................................................... 2-1
213 Product Model Composition and Significance............................................ 2-2
214 Cylinder Number ......................................................................................... 2-2
215 Engine Working Principle ........................................................................... 2-2
216 Engine Block ............................................................................................... 2-3
217 Cylinder Head .............................................................................................. 2-4
218 Overall Engine Performance Parameters .................................................... 2-5
22 Lubrication System .............................................................................................. 2-6
23 Fuel Supply System ............................................................................................. 2-7
231 Fuel Circuit .................................................................................................. 2-8
232 InjectionCircuit ............................................................................................ 2-8
233 Fuel Return .................................................................................................. 2-8
24 Cooling System.................................................................................................... 2-9
241 Function of Cooling System ...................................................................... 2-10
242 Thermostat ................................................................................................. 2-10
25 Intake and Exhaust System ................................................................................ 2-11
251 Intake System ............................................................................................ 2-11
252 Exhaust System.......................................................................................... 2-11
253 Turbocharger ............................................................................................. 2-12
26 Disassembly and Assembly of Engine .............................................................. 2-13
261 Disassembly of Engine .............................................................................. 2-13
262 Assembly of Engine .................................................................................. 2-25
27 Disassembly and Assembly of Fuel Tank ......................................................... 2-37
271 Disassembly of Fuel Tank ......................................................................... 2-37
272 Assembly of Fuel Tank ............................................................................. 2-39
28 Disassembly and Assembly of Radiator ............................................................ 2-41
281 Disassembly of Radiator............................................................................ 2-41
282 Assembly of Radiator ................................................................................ 2-44
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 Service Manual forLG936L Wheel Loader

29 Diagnosis and Troubleshooting of Engine System Common Faults ................. 2-47

291 Engine Fails to Start................................................................................... 2-47
292 Engine Power is Not Sufficient ................................................................. 2-47
293 Exhaust Exceptions (Black Smoke, White Smoke, Blue Smoke)............. 2-48
294 Engine Oil Pressure is Too High or Too Low ........................................... 2-49
295 Large Consumption of Engine Oil ............................................................ 2-50
296 High Coolant Temperature ........................................................................ 2-50

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 Service Manual forLG936L Wheel Loader

2 Engine System

21 General

211 Engine Description

This manual takes WEICHAI DEUTZ

WP6G125E22 engine as example, for LG936L
equipped with other engines can use it as a
reference.
Features of DEUTZ products are: high torque, easy
to cold start and full load running, slender engine
design, low weight, easy to be assembled on the
vehicle, low fuel consumption, low emission, low
noise and low vibration, etc. The engine also
featured with compact overall design and
convenient maintenance.

212 Engine Identification

The serial number is printed on nameplate,which is

located on the engine cylinder block.
Fig. 2-1 Engine
You must indicate the engine type and serial
number when ordering spare parts.

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 Service Manual forLG936L Wheel Loader

213 Product Model Composition and

Significance

WP6G125E22
Generation code
Emission standard
Power
For construction
machinery
6-cylinder
Weichai Power

214 Cylinder Number

The cylinders are numbered sequentially. Ignition

sequence: 1-5-3-6-2-4. From the point of view of
flywheel, the rotating direction of engine is
anti-clockwise.

Fig. 2-2 Cylinder number

215 Engine Working Principle

The diesel engine is designed with four strokes,

every working cycle consists four processes,
i.e.intake, compression, power and exhaust.
Specifically speaking, during air intake, engine
inhales fresh air continuously until the piston
approaches the bottom dead center (BDC),
marking the end of intake. Then, the compression
stroke begins as the piston starts moving upwards,
during which the fresh air is compressed by the
piston and its temperature rises. When the piston
approaches TDC, the diesel is atomized and then
injected into combustion chamber via injector,
where it is mixed with high temperature gas (i.e.
gas mixture is formed) and combusts automatically

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 Service Manual forLG936L Wheel Loader

and quickly. When the pressure generated from

self-combustion forces the piston to move
downwards, the power stroke begins, which will be
ended as the piston gets close to BDC. Following
this, the exhaust stoke starts as the piston moves
upwards by the force of inertia, and when it
approaches TDC, all remaining waste gas resulted
from mixture combustion is discharged, marking
the end of exhaust stroke.
That’s the whole working circle of the diesel
engine.

216 Engine Block

1. Engine assembly
Engine assembly mainly consists ofengine block,
cylinder sleeve, gear room, rearoil sealing cover,
flywheel housing and oil sump tank, etc.
The engine adopts high gantry type block:
------Crankcase sealing surface is lower than
crankshaft axis.
------Enhanced the stiffness of the bottom half
engine block.

1
Fig. 2-3
1 Engine block assembly

Wet-type cylinder sleeve

------The cylinder sleeve outside surface contacts
with the coolant directly;
------Excellentcooling performance, can avoid
cavitation effectively;
Advantages: Make the layout of the whole

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 Service Manual forLG936L Wheel Loader

machine more reasonable, leakage is avoided, and

fuel can be preheated in advance. The convenience
of service and maintenance has been adequately
considered in the design process

217 Cylinder Head

Cylinder head is casted from gray cast iron and

applied unitary structure.

Direction
of water

1
Fig 2-4
1 Cylinder Head
Cylinder head applies high water inflow,which can
improve the cooling speed of the piston and
cylinder sleeve. The temperature of the
water-resisting ring in top of cylinder sleeve
reduces from 300oC to 200oC.

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 Service Manual forLG936L Wheel Loader

218 Overall Engine Performance Parameters

Table 1 Engine parameters

Items Parameters Items Parameters
Model WP6G125E22 Number of cylinders 6
Cylinder diameter/stroke
Type Supercharge 105/130
(mm)
Minimum specific fuel
Rated power (kw) 92 225
consumption (g/kwh)
Rated speed (r/min) 2200 Maximum torque (Nm) 500
Output volume (ml) 6750 Emission standard Chinastage II

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 Service Manual forLG936L Wheel Loader

22 Lubrication System

Fig. 2-5 Route diagram of force-feed lubrication

The oil pump absorbs engine oil from the oil sump
through oil pump, and then the oil flows
throughout the engine via the oil pipes. For
components which have relative motion, wherein
oil film will be formed, the abrasion between parts
can be significantly reduced and service life of
engine is lengthened. The engine is also equipped
with piston cooling nozzle toreduce working
temperature of the piston.

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23 Fuel Supply System

Injector

Fuel
injection
pump
Fuel
fine
Fuel
filter
dilivery
pump
Oil-water
separator

Fuel tank

Fig. 2-6 Fuel system

Fuel supply system includes: fuel pump, governor,

oil transfer pump, fuel filler, injector,and injection
pump, etc.

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231 Fuel Circuit

Firstly, the fuel pump pumps fuel from fuel tankto

fuel injection pump through filterand inlet pipe of
the injection pipe. Some of the fuel enters into
injection circuit, namely, injector – combustion
chamber, most of the fuel goes into the oil return
chamber in cylinder block via injection pump to
form fuel return circuit, stabilized pressure in low
pressure circuit is vitally important for engine
power output. If the situation of under-capacity of
engine occurs, check thefuel pressure first.
The fuel control valve is used to control oil
pressure in fuel return circuit. The major cause to
oil leak (cavitation) of injector is insufficient
pressure of low pressure circuit, so ensure the
cleanness of fuel filter and replace it if necessary.

232 InjectionCircuit

The fuel in injection pump enters into the injector

via a short oil pipe,injector begins to work to inject
fuel into the combustion chamber.

233 Fuel Return

Due to the oil supply rate of fuel pump is more

than ten times larger than the capacity of injector, a
lot of excess fuel will return back to fuel tank via
the pressure control valve,leaked fuel from injector
during working gap returns to fuel tank too, which
has the effect of cooling the combustion. Moreover,
air in oil line can be bleed out under the action of
large amount of return fuel, self-bleeding function
is available.

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24 Cooling System

The coolant pump intakes low temperature water

from an attached radiator through the thermostat,
the cooling water flows through engine oil radiator,
then enters into the water jacket in the cylinder
block to cool the cylinder liner, then the water
enters into water jacket of cylinder head through
water channel, finally returns to the radiator.

Fan heater Fan heater

Pressure limiting valve cover

Expansion
Water
tank

Water
Thermostat outlet
pipe
Fan
Radiator

Air compressor

Cylinder head
Oil cooler

Pump
Diesel engine
block

Fig. 2-7 Cooling system

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241 Function of Cooling System

When the engine is running, a large amount of heat

is generated by fuel combustion and friction
between moving parts, some parts are subjected to
strong heat, especially the parts exposed to burning
gas directly, without proper cooling, the normal
working of engine cannot be guaranteed. The
purpose of cooling system is to keep the engine
working under proper temperature.
WP6G125E22 is water cooling engine. Water is
the direct heat-transfer medium, then the heat is
passed down to air. That is, using a small amount
of water in engine water jacket to absorb excess
heat, in a continuously circulating way, and
thendissipate the heat in the radiator. Because of
the temperature difference between inlet and outlet
of water jacket is small, so the bottom of cylinder
wouldn’t be undercooled, besides, the cooling
intensity can be easily adjusted to keep the engine
working under normal temperature. In winter, hot
water can be used to preheat the engine.

242 Thermostat

The function of thermostat is to change the

circulating intensity (route and flow) along with
engine load and water temperature. Meanwhile, it
is also used to shorten the engine warm-up time, to
reduce fuel consumption and abrasion between
parts.

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 Service Manual forLG936L Wheel Loader

25 Intake and Exhaust System

251 Intake System

Compressed air

Engine Turbocharger
cylinder lubricating oil
inlet

Turbine
Compressor
wheel

Air intake Exhaus

port port

Compressor
impeller
Deflation
Lubricating oil outlet valve

Fig. 2-8 Intake and exhaust system

Air is absorbed in through air filter, and then flows

into turbocharger. After the air outflows from
turbocharger, the condensed air finally arrives at
the cylinder through the inlet manifold and intake
valve, mixes up with the fuel and burns.

252 Exhaust System

Firstly, the exhaust gas flows into the silencer

through turbocharger, discharge into the
environment through exhaust pipes at last.

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253 Turbocharger

The turbocharger is driven by exhaust gas, the

exhaust gas flows through the turbine casing on its
way to DPF module.
Exhaust airflow drives the turbine rotor in the
turbine casing. The compressor rotor and turbine
rotor locate on the same shaft, the former located in
the housing that connected between air filter and
intake manifold.

Fig. 2-9 Turbocharger When compressor rotor rotates, it will suck air
from the air filter. The turbocharger is equipped
with an exhaust by-pass valve. The exhaust by-pass
valve is controlled by pressurized air, to allow a
small amount of exhaust gas bypass turbine rotor
under high engine speed (highpressurized air
pressure).

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 Service Manual forLG936L Wheel Loader

26 Disassembly and Assembly of Engine

261 Disassembly of Engine

These following steps could be referred to disassemble the engine from the machine when the
engine needs to be replaced, examined or repaired.

Preparation
Disconnect starter wiring Drain coolant and engine oil
harness Remove radiator
Disconnect A/C compressor
wiring harness Hydraulic oil tank
Disconnect generator Engine wiring harnesses
wiring harness
Disconnect sensor wiring Fuel absorption pipe
harnesses Fuel return pipe Engine
Fan heater water inlet and assembly
return pipes
A/C compressor pipes
Intake and exhaust pipe

Disassemble air filter Flameout cable

Disconnect A/C Air compressor pipes
compressor
Disconnect water valve of Water inlet and return pipes
fan heater Accessories

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 Service Manual forLG936L Wheel Loader

1. Start the machine and drive it to the

maintenance position. Keep the bucket flat on
ground. Press the parking brake switch on the
operation box. Turn the key of the electrical
lock toshut down the engine, turn off the
electrical power of the whole machine 5min
later. Wedge the front and rear tires with wood
blocks.
1 2 ★ Do the following operations after the
Fig. 2-10
loader cools down. During the processes of
1 Wood block 2 Tire
disassembly, all the pipeline joints should be
wrapped up to avoid the debris entering
into the pipeline.
2. Open the water drain valve of radiator. Drain
the cooling water out and contain them with
clean vessel.
Coolant

1
Fig. 2-11
1 Water drain valve

3. Open the oil drain plug on engine sump and

drain the engine oil, contain them with a clean
vessel.
Engine oil

1
Fig. 2-12
1 Oil drain plug

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 Service Manual forLG936L Wheel Loader

4. Remove the engine hood.

Refer to Disassembly of Radiatorin this
chapter.

1
Fig. 2-13
1 Radiator

5. Remove the hydraulic oil tank.

Refer to Disassembly of Hydraulic Oil
Tankin chapter 9.

1
Fig. 2-14
1 Hydraulic oil tank

6. Disconnect wiring harness of engine.

★ Don’t damage the wiring harness
connector.

1 2
Fig. 2-15
1 Starter power wiring harness
2 Engine assembly

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7. Remove the electric generatorwiring harness.

1 2
Fig. 2-16
1 Electric generator
2 Electric generator wiring harness

8. Disconnect the wiring harnessof

A/Ccompressor.

1 2
Fig. 2-17
1 Wiring harness
2 A/Ccompressor

9. Disconnect the sensorwiring harnesses.

1 2
Fig. 2-18
1 Water temperature sensor
2 Engine oil pressure sensor

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10. Disconnect the high pressure pipe and low

pressure pipe of compressor.

1 2
Fig. 2-19
1 High pressure pipe of compressor
2 Low pressure pipe of compressor

11. Disconnect engine fuel absorption pipe and

fuel return pipe.
Oil may drop, protect the oil port to avoid
contamination.

1 2
Fig. 2-20
1 Fuel return pipe connector
2 Fuel absorption connector

12. Cut off the water inlet pipe of fan heater.

Protect the connector and avoid the
contamination.

1 2
Fig. 2-21
1 Water inlet of warm air blower
2 Engine
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 Service Manual forLG936L Wheel Loader

13. Disconnectwater return pipe of fan heater.

Protect the connector and avoid the

contamination.

1
Fig. 2-22
1 Return pipe of warm air blower

14. Disconnect the connection between intake

hose and air filter.
Refer to Disassembly of engine accessoriesin
this chapter.

1 2
Fig. 2-23
1 Intake hose
2 Clamp

15. Remove the nut, cut off the connection

between silencer and turbocharger.
Take precautions to avoid foreign matter
entering into supercharger.

1 2 3
Fig. 2-24
1 Silencer 2 Nut 3 Turbocharger

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 Service Manual forLG936L Wheel Loader

16. Disconnect the clamp of silencer.

1 2
Fig. 2-25
1 Silencer 2 Clamp

17. Disconnect the fixing clamp of air filter.

1 2
Fig. 2-26
1 Fixing clamp 2 Air filter

18. Remove the clamps and disconnect the

connection between waterinlet pipe of radiator
and engine.

1 2 3
Fig. 2-27
1 Clamp
2 Inlet of radiator 3 Radiator

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 Service Manual forLG936L Wheel Loader

19. Disconnect the water return pipe from engine.

1
Fig. 2-28
1 Return pipe of engine

20. Hang the enginewith a lifting rope, open

torque converter hood, remove the connecting
bolts between flywheel disc and torque
converter intermedium ring, remove the
connecting bolts and gaskets between flywheel
casing and torque converter.

1 2
Fig. 2-29
1 Connecting nut of torque converter
2 Connecting bolt of transmission box

21. Remove the transmission oil pipe.

1 2
Fig. 2-30
1 Clamp
2 Transmission oil pipe

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 Service Manual forLG936L Wheel Loader

22. Remove the accelerator cable.

1
Fig. 2-31
1 Accelerator cable

23. Remove the flameout cable.

1
Fig. 2-32
1 Flameout cable

24. Remove the air compressor pipe.

1 2
Fig. 2-33
1 Air compressor pipe
2 Air compressor

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25. Remove the fixing bolt of engine support.

1
Fig. 2-34
1 Fixing bolt of engine support

26. Lift down the engine.

★ ATTENTION: Ensure all connecting

parts are removed from the engine, and no
interference involved during lifting.

1
Fig. 2-35
1 Engine

27. Disassembly of engine accessories

1 Disassembly of air filter
a) Remove the clamp,disconnect the
connection between intake hose and air
filter.

1 2
Fig. 2-36
1 Intake hose 2 Clamp

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b) Remove the fixing clamp of air filter and

take down the air filter.

1 2
Fig. 2-37
1 Fixing clamp of air filter
2 Air filter

2 Disassembly of A/C compressor

a) Loosen the adjusting nut and rotate the
compressor.
b) Take down the V belt.
c) Loosen the fixing bolts and take down the
compressor assembly.

1 2 3
Fig. 2-38
1 Adjusting bolt
2 Fixing bolt 3 V belt

3 Disassembly of water inlet/return valve of

fan heater
a) Remove the water return valve of fan
heater.

1
Fig. 2-39
1 Water return valve of fan heater

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b) Remove the water inlet valve of fan heater.

1
Fig. 2-40
1 Water inlet valve of fan heater

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262 Assembly of Engine

Refer to the following steps to recover the engine.

Double end studs

Hang the engine
Connect starter wiring Speed changer - torque
harness converter assembly
Connect A/C compressor Engine support
wiring harness Engine wiring
Connect generator harnesses
wiring harness Fuel absorption pipe
Connect sensor wiring Fuel return pipe
harnesses Fan heater water inlet
and return pipe
A/C compressor pipes
Intake and exhaust pipe Engine
Flameout cable assembly
Air compressor pipes
Water inlet and return
pipe
Assemble air filter Hydraulic oil tank
Install A/C compressor Engine hood
Install water valve of Accessories
fan heater Fill antifreeze
Fill engine oil

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 Service Manual forLG936L Wheel Loader

1. Pre-tighten the double end studs.

★ Apply some diesel on the studs before
assembling.

1 2 3
Fig. 2-41
1 Flywheel
2 Stud
3 Flywheel cover
2. Hang up the engine and put it on the frame
properly so as to assemble the speed changer –
torque converter assembly.
★ 1 Make sure the lifting rope is in good
condition.
2 Notice the installation site, avoid
crashing.
3 Nobody is allowed to stand under of
engine.
1
Fig. 2-42
1 Engine
3. Connect the speed changer-torque converter
assembly to the engine.
1) Apply a layer of sealant on the end face of
engine. Remove the top cover plate of the
speed changer-torque converter assembly.
Connect the torque converter to the engine
with bolts and gaskets.
2) Connect the flywheel to speed changer - torque
1 2 3 converter assembly with nuts.
Fig. 2-55
1 Speed changer - torque converter ★ Tighten the all connection bolts in
assembly round-group-bolts way. Avoid debris
2 Fixing bolt 3 Engine entering into the torque converter when
connecting the intermedium ring.
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 Service Manual forLG936L Wheel Loader

4. Install the top cover plate of torque converter.

After check is finished, assemble the top cover
plate and tighten it.

1 2 3 4
Fig. 2-44
1 Flywheel housing 2 Cover plate
3 Cover plate fixing bolt
4 Speed changer - torque converter
assembly

5. Connect the transmission oil return pipe.

1
Fig. 2-45
1 Oil return pipe

6. Install and tighten the connecting bolts of

engine support.
120~200Nm

1 2
Fig. 2-46
1 Connecting bolt of engine support
2 Engine
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 Service Manual forLG936L Wheel Loader

7. Connect the starterpower wiring harness.

1 2
Fig. 2-47
1 Starter power wiring harness
2 Engine

8. Connect compressor wiring harness.

1 2
Fig. 2-48
1 Compressor wiring harness
2 Compressor

9. Connect generator wiring harness.

1 2
Fig. 2-49
1 Generator wiring harness
2 Generator

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 Service Manual forLG936L Wheel Loader

10. Connect sensor wiring harnesses.

1 2
Fig. 2-50
1 Water temperature sensor
2 Engine oil temperature sensor

11. Connectengine fuel absorption pipe and return

pipe.

1 2
Fig. 2-51
1 Engine fuel return pipe
2 Engine fuel suction pipe

12. Connectfan heater water inlet pipe.

1 2
Fig. 2-52
1 Fan heater water inlet pipe
2 Generator

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13. Connect fan heater water return pipe.

★ Fasten slowly until the rubber hoseis
slightly deformed.

1
Fig. 2-53
1 Fan heater water return pipe

14. Connect the high pressure pipe and low

pressure pipe of compressor.

1 2
Fig. 2-54
1 Low pressure pipe of compressor
2 High pressure pipe of compressor

15. Fasten the clamp, connect .intake hose and air

filter, install the compressor.
Refer toAssembly of engine accessoriesin this
chapter.

1 2
Fig. 2-55
1Intake hose
2 Clamp

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16. Fasten the clamp, tighten the air filter.

1 2
Fig. 2-56
1 Clamp 2 Air filter

17. Install connecting nuts, connect silencer and

turbocharger.

1 2 3
Fig. 2-57
1 Silencer 2 Nut
3 Supercharger

18. Fasten the clamp to fix the silencer.

1 2
Fig. 2-58
1 Silencer 2 Clamp

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19. Install accelerator cable.

1
Fig. 2-59
1 Accelerator cable

20. Installflameoutcable.

1
Fig. 2-60
1 Flameoutcable

21. Install air compressor pipe.

1
Fig. 2-61
1 Air compressor pipe

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22. Install radiator water inlet pipe.

★ Fasten slowly until the rubber hoseis
slightly deformed.

1 2 3
Fig. 2-62
1 Radiator water inlet pipe
2 Clamp
3 Radiator

23. Connect engine waterreturn pipe.

★ Fasten slowly until the rubber hoseis
slightly deformed.

1 2
Fig. 2-63
1 Radiator
2 Water return pipe

24. Install hydraulic oil tank.

Refer to Assembly of hydraulic oil tank in
chapter 9.

1 2
Fig. 2-64
1 Engine
2 Hydraulic oil tank

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25. Install engine hood.

Refer to Assembly of engine hood in chapter 8.

1
Fig. 2-65
1 Engine hood

26. Addcoolant.
Coolant

1 2
Fig. 2-66
1 Radiator
2 Coolant adding port

27. Fill engine oil.

Engine Oil

1
Fig. 2-67
1 Engine oil filling port

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28. Assemble engine accessories.

1) Install the water valve of fan heater.
★ ATTENTION: Coat the water
valvewith sealant start from the second
thread for about 3~5 threads.
AT262 sealant

1 2
Fig. 2-68
1 Fan heater water valve
2 Engine

2) Install A/C compressor.

Refer toAssembly of compressor inA/C
system.

1 2 3 4
Fig. 2-69
1 Air condition compressor
2 Adjusting nut3 V belt
4 Engine

3) Install the air filter.

a) Pretighten the air filter and fix the clamp.

1 2
Fig. 2-70
1 Air filter 2 Clamp

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b) Install lock clamp between intake hose

and air filter.
★ Fasten slowly until the rubber hoseis
slightly deformed.

1 2
Fig. 2-71
1 Intake hose 2 Clamp

c) Fasten lock clamp of air filter.

1 2
Fig. 2-72
1 Air filter 2 Clamp

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27 Disassembly and Assembly of

Fuel Tank

271 Disassembly of Fuel Tank

1. Start the machine and park it on level

capacious ground. Lower the bucket and flat it
on ground. Pull up the parking brake and
wedge the front and rear tires with wood
blocks, turn of main power 5min later.
★ ATTENTION: Do the disassembly
1 2 after the loader is cooled.
Fig. 2-73
1 Tire 2 Wood block

2. Loosen the screw plug on the bottom of tank

and drain the oil. Contain the oil with clean
vessel and covers it to avoid falling sundries.
★ ATTENTION: Fuel oil is inflammable.
In the processes of maintaining, the fire is
forbidden and the place should be far
away from fire. At the same time, prevent
1 2 the generation of fire, for example:
Fig. 2-74 Bumping brings spark.
1 Ball valve 2 Fuel Tank

3. Remove oil level sensor wiring harness of fuel

tank.

1 2
Fig. 2-75
1 Oil level sensor connector
2 Oil level sensor
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 Service Manual forLG936L Wheel Loader

4. Loosen the clamp of fuel absorption pipe and

take down the pipe from fuel tank.

1 2
Fig. 2-76
1 Fuel absorption pipe
2 Fuel Tank

5. Remove the bolts and disconnect the fuel

return pipe.

1
Fig. 2-77
1 Fuel return pipe

6. Hang the fuel tank, disassemble the fastening

bolts and remove fuel tank from rear frame.

1
Fig. 2-78
1 Fastening bolt * 3

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7. Lift down the fuel tank.

★ ATTENTION: Ensure all connecting
parts are removed from the tank, and no
interference involved during lifting.

1
Fig. 2-79
1 Fuel tank

272 Assembly of Fuel Tank

1. Lift and assemble the fuel tank.

Clean the fuel tank. Lift the fuel tank assembly
to rear-bottom site of the rear frame.

1
Fig. 2-80
1 Fuel tank

2. Fix the fuel tank on the rear frame with bolts.

120~180N·m

1
Fig. 2-81
1 Fastening bolt

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3. Connectengine fuel return pipe and tighten it.

1
Fig. 2-83
1 Fuel return pipe
2 Hollow bolt

4. Connect fuel absorption pipe to the tank and

fix it with clamp.

1
Fig. 2-83
1 Fuel absorption pipe

5. Install the oil level sensor on the fuel tank.

1 2
Fig. 2-84
1 Oil level sensorconnector
2 Oil lever sensor

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6. Add fuel.
56L

Keep away from open flame when adding.

1 2
Fig. 2-85
1 Fuel adding port 2 Fuel tank

28 Disassembly and Assembly of

Radiator

281 Disassembly of Radiator

1. Open the drain valve on the bottom of radiator.

Drain out the coolant and contain them with
clean vessel.
Antifreeze

1
Fig. 2-86
1 Water drain hose

2. Hang theengine hood up.

Refer to Disassembly of engine hood in
chapter 8.

1
Fig. 2-87
1 Engine hood

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 Service Manual forLG936L Wheel Loader

3. Disconnect the transmission oil return pipe

from radiator.

1
Fig. 2-88
1 Transmission oil return pipe

4. Disconnect the transmission oil inlet pipe from

radiator.

1 2
Fig. 2-89
1 Transmission oil inlet pipe
2 Radiator

5. Disconnect the hydraulic oilpipe from radiator.

1 2
Fig. 2-90
1 Hydraulic oil return pipe
2 Hydraulic oil inlet pipe

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6. Disconnect the radiator water inlet pipe from

radiator.

1 2
Fig. 2-91
1 Radiator water inlet pipe
2 Radiator

7. Disconnect the radiator wateroutlet pipe.

1 2
Fig. 2-92
1 Radiator
2 Radiator water outlet pipe

8. Remove the fixing bolts.

1 2
Fig. 2-93
1 Fixing bolt
2 Radiator

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9. Lift theradiator down.

★ ATTENTION: Ensure all connecting
parts are removed from the radiator, and
no interference involved during lifting.

1
Fig. 2-94
1 Radiator

282 Assembly of Radiator

1. Clean the radiator and lift it up to place it on

relevant position ofthe roader rear frame.

1
Fig. 2-95
1 Radiator

2. Fasten the fixing bolts of radiator.

15~35Nm

1 2
Fig. 2-96
1 Bolt 2 Radiator

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3. Connect the radiator water return pipe.

★ Fasten slowly until the rubber hoseis
slightly deformed.

1 2
Fig. 2-97
1 Radiator water return pipe
2 Radiator

4. Connect radiator and water inlet pipe.

★ Fasten slowly until the rubber hoseis
slightly deformed.

1 2
Fig. 2-98
1 Radiator water inlet pipe
2 Radiator

5. Connecthydraulic oil inlet pipe and return

pipe to radiator.
20~30Nm

1 2 3
Fig. 2-99
1 Hydraulic oil return pipe
2 Hydraulic oil inlet pipe
3 Radiator

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6. Connect the transmission oil inlet pipe.

120~160Nm

1 2
Fig. 2-100
1 Transmission oil inlet pipe
2 Radiator

7. Connect the transmissionoil return pipe.

120~160Nm

1 2
Fig. 2-101
1 Radiator
2 Transmission oil return pipe

8. Assemble the engine hood.

Refer toAssembly of engine hood in chapter
8.

1
Fig. 2-102
1 Engine hood

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29 Diagnosis and Troubleshooting of Engine System Common Faults

291 Engine Fails to Start

Caused by starting system

1 Power shortage of storage battery.
Solution: Check the battery carefully, recharge or replace it.
2 Damaged starting motor.
Solution: repair or replace the motor.
Caused by oil supply system
1 There is air in the oil system.
Solution: Unchoke the oil circuit, tighten all joints and discharge air.
2 Blocking of oil system.
Solution: Unchoke the oil circuit, tighten all joints and discharge air.
3 The diesel filter element is particularly dirty.
Solution: Replace the filter element.
4 Serious wear damage of plunger/delivery valve.
Solution: Repair the fuel pump professionally.
5 Damaged low pressure fuel pump.
Solution: Replace the fuel pump
Adjustment factors
1 Dislocation of fuel injection advance angle.
Solution: Adjust the fuel injection advance angle.
2 Change of valve clearance.
Solution: Check and adjust valve clearance.
3 Oil shortage when starting
Solution: Check the fuel pump professionally.

292 Engine Power is Not Sufficient

1 Blockage of fuel filter or fuel pump oil inlet pipe connector filter screen.
Solution: Clean or replace it/them.
2 Low injection pressure or bad atomization.
Solution: Troubleshoot the injector or replace inject nozzle matching parts.
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3 Serious wear damage of precise injection nozzle matching parts.

Solution: Regulate oil supply or troubleshoot plunger and barrel assembly.
4 Air infiltrate into the fuel system.
Solution: Discharge air of the fuel system.
5 Incorrect fuel injection advance angle.
Solution: Adjust the angle according provisions.
6 Non-uniform oil supply of each cylinder.
Solution: Adjust oil supply.
7 Blockage of air filter.
Solution: Clean or replace the filter element.
293 Exhaust Exceptions (Black Smoke, White Smoke, Blue Smoke)

The engine gives off blue smoke

1 High engine oil level of engine sump.
Solution: Drain redundant engine oil, and make sure the oil level is within specified range.
2 Diesel flows into oil sump due to oil-fuel injector needle-valvepoorlysealed or stuck in open
position.
Solution: Clean and adjust the injector or replace the needle valve matching parts.
3 Damaged fuel pump plunger bushing sealing ring (P pump), or bad sealing between plunger
bushing and pump body, the fuel flows into oil sump along engine oil passage.
Solution:Replace the sealing ring.
4 Damaged valve oil seal or excessive clearance between the valve and tube.
Solution: Replace all faulted valves, pipes and oil seal (the oil seal must be replaced once being
disassembled; if the clearance meets the requirements after the valve is replaced, you can spare the
tube).
5 Damaged sealing ring of turbocharger, engine oil burns after enters into the combustion
chamber along air inlet passage.
Solution: Repair or replace.
The engine gives off white smoke
1 There is moisture in the fuel system.
Solution: Clean the fuel tank and filter, and use qualified diesel oil.
2 Abrasion of cylinder valve.

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Solution: Replace it.

3 Bad atomization of injected fuel, the fuel fails to burn in the combustion champ.
Solution: Adjust the injector and fuel supply advance angle.
The engine gives off black smoke
1 Exhaust back pressure is too high or exhaust pipeline is blocked.
Solution: Reduce bend positions of pipeline; dust out the silencer.
2 The injection lags
Solution: Adjust fuel injection advance angle.
3 The injector doesn’t work normal or being damaged.
Solution: Dismantle, clean and check.
4 Poor quality of diesel or wrong brand.
Solution: Replace the diesel.
5 Severe wear of cylinder liner and piston group.
Solution: Replace worn parts

294 Engine Oil Pressure is Too High or Too Low

Engine oil pressure is too high

1 Malfunctioned engine oil display device.
Solution: Replace the display device.
2 High viscosity of engine oil
Solution: Choose specified brand engine oil, and take preheating action when starting the machine in
winter.
3 Too little gap in force-feed lubricating positions or blocked engine oil filter.
Solution: Adjust the gap, clean or replace the filter.
4 Misadjusted pressure restrict valve.
Solution: Readjust the spring force of the valve, so the engine oil pressure can drop to specified value.
Engine oil pressure is too low
1 Abrasions of engine oil pump or damaged sealing gasket.
Solution: Repair the pump and replace the gasket.
2 The suction oil flow reduces
Solution: Check oil capacity, add engine oil and clean the suction filter.
3 Large engine oil leakage.
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Solution: Check whether the lubricating pipe is broken; check and adjust the fitting clearance of
bearings in crankshaft and camshaft as required.
4 Blockage of engine oil filter or cooler.
Solution: Check and clean engine oil filter and cooler.
5 Low viscosity of engine oil
Solution: Choose specified brand engine oil.
6 Misadjusted pressure restrict valve.
Solution: Clean the valve; readjust or replace the spring.
7 Low displaced engine oil pressure.
Solution: Check and replace engine oil pressure sensor and pressure gauge.
295 Large Consumption of Engine Oil

1 Improper engine oil viscosity.

Solution: Choose proper engine oil.
2 High negative pressure in combustion chamber, result in engine oil spraying up to combustion
chamber.
Solution: Examine the reason for high negativepressure and fix it.
3 Change of rotating speed and operating mode.
Solution: Test showed that with the increase of rotating speed, engine oil consumption rises
obviously, operate the engine according to the rules.
296 High Coolant Temperature

1 Improper selection of coolant or shortage of cooling water.

Solution: Choose suitable coolant and add to specified level.
2 Blockage of water radiator.
Solution: Put the radiating fins back to their original positions with stalloy carefully, after they return
to flat shape, clean them with compressed air or water gun.
3 Wrong indication of waterthermometer or warning light.
Solution: Use the waterthermometer to measure the temperature of water temperature sensor area, see
whether the measured temperature isconsistent with actual value.
4 Low rotating speed of fan, the blades are deformed or installed backwards.
Solution:Loosened rubber belt will lead to slipping, which result in low rotating speed of fan. Adjust
the belt if necessary; if the rubber layer aged, damaged or fractured, replace it. If the blades are
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deformed, replace them.

5 Malfunction of water cooling pump.
Solution: Replace the pump.
6 Malfunction of thermostat.
Solution: Replace the thermostat.
7 Damaged cylinderhead gaskets.
Solution: Replace them.
8 Overloaded operation of diesel engine.
Solution:Lower the load of engine.

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