TEN00770-02

BULLDOZER D51EX -24

D51PX -24
SERIAL NUMBERS 10001 and up

WARNING
Unsafe use of this machine may cause serious injury or
death. Operators and maintenance personnel must read
this manual before operating or maintaining this machine.
This manual should be kept near the machine for
reference and periodically reviewed by all personnel who
will come into contact with it.
NOTICE
Komatsu has Operation & Maintenance Manuals
written in some other languages. If a foreign language
manual is necessary, contact your local distributor for
availability.
Foreword

1-1
Read This Manual Foreword

Read This Manual

This manual gives details of the operation and methods of inspection and maintenance for this machine that
must be observed in order to use the machine safely. Most accidents are caused by the failure to follow funda-
mental safety rules for the operation and maintenance of machines.
Read, understand and follow all precautions and warnings in this manual and on the machine before performing
operation and maintenance. Failure to do so may result in serious injury or death.
Komatsu cannot predict every circumstance that might involve a potential hazard when the machine is used.
Therefore, the safety messages in this manual and on the machine may not include all possible safety precau-
tions.
If you perform any operation, inspection, or maintenance under conditions that are not described in this manual,
understand that it is your responsibility to take the necessary precautions to ensure safety. In no event should
you or others engage in the prohibited uses or actions described in this manual. It is dangerous to perform im-
proper operation and maintenance of the machine. It may cause serious injury or death.
If you sell the machine, be sure to give this manual to the new owner together with the machine.
Always keep this Operation and Maintenance Manual in the indicated location so that all relevant personnel can
read it at any time.
Storage location for Operation and Maintenance Manual:
It is provided on the back of the backrest of operator's seat.

REMARK
When the machine is equipped with the air suspension seat,
store the Operation and Maintenance Manual in the steel box
on the back of the seat.

If this manual is lost or damaged, contact Komatsu or your Komatsu distributor and tell them about the machine
model name and the serial No. immediately to arrange for its replacement.
For the machine model name and the serial No., see the machine serial No. plate. In order to arrange the prop-
er Operation and Maintenance Manual, you will need to provide the machine model name and the serial No.
This manual uses the International System of Units (SI) for units of measurement. For reference, units that have
been used in the past are given in { }.
The explanations, values, and illustrations in this manual have been prepared based on the latest information
available as of the date of its publication. Continuing improvements in the design of this machine may lead to
additional changes that are not reflected in this manual. If there is any question or suggestion, consult your Ko-
matsu distributor.
The numbers in the illustrations correspond to the numbers in ( ) in the text. (Example: 1 → (1))
Komatsu delivers machines that comply with all applicable regulations and standards of the country to which it
has been shipped. If this machine has been purchased in another country, it may lack certain safety devices and
specifications that are necessary for use in your country. If there is any question about whether your product

1-2
Foreword Read This Manual

complies with the applicable standards and regulations of your country, consult your Komatsu distributor before
operating the machine.
Some of Komatsu machines have the software based on the Open Source Software (OSS).
By the license of the OSS, Komatsu publishes the license information of the software to be used in the website
that follows.
https://www.komatsu.jp/en/ProductInfo/opensoft/

1-3
Safety Information Foreword

Safety Information
To enable you to use the machine safely, and to prevent personal injury to operators, service personnel or by-
standers, the precautions and warnings included in this manual and the safety signs attached to the machine
must always be observed.
To identify important safety messages in the manual and on the machine labels, the following signal words are
used.
The “Safety Alert Symbol” identifies important safety messages on machines, in manuals, and elsewhere. When
you see this symbol, be alert to the risk of personal injury or death. Follow the instructions in the safety mes-
sage.
This signal word indicates an imminently hazardous situation which, if not avoided, will result
in death or serious injury.
This signal word indicates a potentially hazardous situation which, if not avoided, could result
in death or serious injury.
This signal word indicates a potentially hazardous situation which, if not avoided, may result
in minor or moderate injury. It may also be used to alert against unsafe practices that may
cause property damage.

The following signal words are used to alert you to information that must be followed to avoid damage to the
machine.
If precautions described are not observed, the machine may be damaged or the service life
may be reduced.
This word is used for information that is useful to know.

1-4
Foreword Introduction

Introduction
Main Use of Machine
This Komatsu machine is designed to be used mainly for the following work:
• Dozing work
• Leveling work
• Cutting into hard or frozen ground or ditching
• Works of felling trees and removing stumps
For details of work procedure, see OPERATION, “RECOMMENDED APPLICATIONS”.

Directions of Machine

In this Operation and Maintenance Manual, the directions of the machine (front, rear, right, left) are determined
according to the view from operator's seat (E) in the direction of travel (front) of the machine.
(A) Front (D) Right
(B) Rear (E) Operator's seat
(C) Left (F) Sprocket

Visibility from Operator's Seat

This machine complies with the visibility standard (ISO5006).
This machine maintains a proximity visibility of a height of 1.5 m {4 ft 11 in} at a point 1 m {3 ft 3 in} away from
the outside surface of the machine, and a visibility for a radius of 12 m {39 ft 4 in}.
Protective Structures
This machine is equipped with a structure to protect the operator (ROPS) conforming to ISO3471.

1-5
Engine Technology to Conform Exhaust Gas Emission Foreword

Engine Technology to Conform Exhaust Gas Emission

This engine complies with the EPA Tier4 Final emission regulation in North America.
REMARK
The catalyzer to clean the exhaust gas absorbs some materials. If the temperature of catalyzer rises immediate-
ly after the start or during the aftertreatment devices regeneration, the absorbed materials could come off and
be discharged. At this time, the exhaust gas can have a color temporarily.
About Diesel Exhaust Fluid (DEF)
Diesel Exhaust Fluid is the aqueous urea solution for the SCR system.
In the SCR system, spraying the reagent (Diesel Exhaust Fluid) into the exhaust gas produces a reaction be-
tween the nitrogen oxides and ammonia generated from the urea solution and decomposes the nitrogen oxides
(NOx) into nitrogen and water.
DEF is the abbreviation for Diesel Exhaust Fluid, and is represented as DEF throughout this manual.
DEF is a colorless clear and aqueous urea solution made with 32.5 % urea (AUS32) and 67.5 % deionized wa-
ter. Urea as main constituent is a material which is used for cosmetics, medical and pharmaceutical products,
and fertilizer, etc.
Use commercial DEF, that is API (American Petroleum Insti-
tute) certified and fulfills the quality requirements of ISO
22241-1. The certified DEF has the API DIESEL EXHAUST
FLUID Certification Mark shown as follows. Look for the API
DEF Certification Mark when you purchase DEF.
API Diesel Exhaust Fluid Certification Mark is the trademark of
API (American Petroleum Institute).

1-6
Foreword Product Information

Product Information
When requesting service or ordering replacement parts, inform your Komatsu distributor of the following items.

Location of Product Identification Number (PIN) and Machine Serial No.

Plate
It is located at front left of the operator's seat.
The design of the nameplate varies according to the district.

Location of Engine Number Plate

It is installed inside the inspection cover on the left side of the machine.

1-7
Product Information Foreword

Service Meter Location

This is displayed on the machine monitor.

Your Machine Serial Numbers and Distributor

Machine serial No.
Engine serial No.
Product identification
number (PIN)
Distributor name
Address
Phone/Fax
Service personnel

1-8
Foreword Table of Contents

Table of Contents
Foreword.......................................................................................................................................................... 1-1
Read This Manual ..................................................................................................................................... 1-2
Safety Information ..................................................................................................................................... 1-4
Introduction ............................................................................................................................................... 1-5
Main Use of Machine ......................................................................................................................... 1-5
Directions of Machine......................................................................................................................... 1-5
Visibility from Operator's Seat ............................................................................................................ 1-5
Engine Technology to Conform Exhaust Gas Emission............................................................................. 1-6
Product Information................................................................................................................................... 1-7
Location of Product Identification Number (PIN) and Machine Serial No. Plate .................................. 1-7
Location of Engine Number Plate....................................................................................................... 1-7
Service Meter Location ...................................................................................................................... 1-8
Your Machine Serial Numbers and Distributor.................................................................................... 1-8
Safety .............................................................................................................................................................. 2-1
Safety Labels ............................................................................................................................................ 2-2
Location of Safety Labels ................................................................................................................... 2-3
Safety Labels ..................................................................................................................................... 2-4
General Precautions Common to Operation and Maintenance.................................................................. 2-9
Precautions Before You Start Operation............................................................................................. 2-9
Prepare for Safety Operation ............................................................................................................. 2-9
Precautions to Prevent Fire...............................................................................................................2-11
Precautions When You Get on or Off Machine ................................................................................. 2-13
Do Not Get Caught .......................................................................................................................... 2-14
Precautions Related to Protective Structures ................................................................................... 2-15
Unauthorized Modification................................................................................................................ 2-15
Precautions Related to Attachments and Options ............................................................................ 2-15
Precautions When You Operate Engine Inside Building ................................................................... 2-15
Precautions for Operation ....................................................................................................................... 2-16
Precautions for Jobsite..................................................................................................................... 2-16
Start Engine ..................................................................................................................................... 2-19
Precautions for Operation ................................................................................................................ 2-21
Precautions for Transportation ......................................................................................................... 2-25
Towing and being Towed .................................................................................................................. 2-26
Precautions for Maintenance................................................................................................................... 2-27
Precautions Before Inspection and Maintenance ............................................................................. 2-27
Precautions for Check and Maintenance.......................................................................................... 2-31
Precautions for DEF................................................................................................................................ 2-38
General Character and Precautions for Handling ............................................................................. 2-38
Precautions When You Add ............................................................................................................. 2-38
Precautions for Storage ................................................................................................................... 2-38
Precautions for Fire Hazard and Leakage ........................................................................................ 2-38
Other Precautions ............................................................................................................................ 2-38
Operation ......................................................................................................................................................... 3-1
General View ............................................................................................................................................ 3-2
Names of Machine Equipment ........................................................................................................... 3-2
Control Levers and Pedals ................................................................................................................. 3-3
Explanation of Components ...................................................................................................................... 3-5
Machine Monitor Equipment............................................................................................................... 3-5
Switches .......................................................................................................................................... 3-95
Control Levers and Pedals ............................................................................................................. 3-101
Other Equipment............................................................................................................................ 3-108
Machine Operations and Controls ......................................................................................................... 3-150
Checks and Adjustment Before You Start Engine........................................................................... 3-150
How to Start Engine ....................................................................................................................... 3-188
Operations and Checks After You Start Engine .............................................................................. 3-193
How to Stop Engine ....................................................................................................................... 3-197

1-9
Table of Contents Foreword

How to Start Machine (Travel FORWARD and REVERSE) and Stop Machine............................... 3-199
How to Shift Gears ......................................................................................................................... 3-203
How to Switch Between FORWARD and REVERSE...................................................................... 3-207
Steer Machine................................................................................................................................ 3-208
Recommended Working Modes for Works ..................................................................................... 3-212
Precautions for Operation .............................................................................................................. 3-215
Precautions When You Work on Slope........................................................................................... 3-216
Do Not Open Door While You Operate Machine............................................................................. 3-216
Do Not Change CAB Glass in Any Way that Will Block the View.................................................... 3-216
Precautions for Floating Operation................................................................................................. 3-216
Precautions for Blind Areas Caused by CAB and ROPS Structures............................................... 3-217
Recommended Applications........................................................................................................... 3-217
How to Adjust Work Equipment...................................................................................................... 3-220
Tips for Longer Undercarriage Life ................................................................................................. 3-222
How to Park Machine ..................................................................................................................... 3-225
How to Examine After You Complete Work .................................................................................... 3-227
Lock ............................................................................................................................................... 3-228
Handle Air Conditioner .......................................................................................................................... 3-233
Explanation of Air Conditioner Components ................................................................................... 3-233
How to Operate to Prevent Dust from Entering Into CAB ............................................................... 3-234
How to Examine During Off Season ............................................................................................... 3-235
How to Replace Receiver............................................................................................................... 3-235
Handle Radio ........................................................................................................................................ 3-236
Explanation of Radio Equipment .................................................................................................... 3-236
Operate Radio................................................................................................................................ 3-239
Antenna ......................................................................................................................................... 3-241
Transportation ....................................................................................................................................... 3-242
Travel on Road............................................................................................................................... 3-242
Precautions When You Transport Machine .................................................................................... 3-242
Transportation ................................................................................................................................ 3-242
Remove CAB ................................................................................................................................. 3-242
Remove Work Equipment .............................................................................................................. 3-242
Load onto and Unload from a Trailer .............................................................................................. 3-243
How to Lift Machine........................................................................................................................ 3-246
Cold Weather Operation........................................................................................................................ 3-248
Cold Weather Operation Information .............................................................................................. 3-248
Precautions After Daily Work Ends in Cold Weather ...................................................................... 3-250
After Cold Weather Season............................................................................................................ 3-250
Precautions for Long-Term Storage....................................................................................................... 3-251
Prepare for Long-Term Storage...................................................................................................... 3-251
Maintenance During Long-Term Storage........................................................................................ 3-251
Start Machine After Long-Term Storage ......................................................................................... 3-252
Troubles and Procedures ...................................................................................................................... 3-253
Precautions When You Tow Machine ............................................................................................. 3-253
Precautions for Discharged Battery................................................................................................ 3-255
Other Trouble ................................................................................................................................. 3-262
Maintenance .................................................................................................................................................... 4-1
Precautions for Maintenance..................................................................................................................... 4-2
Examine Service Meter Reading ........................................................................................................ 4-2
Komatsu Genuine Replacement Parts ............................................................................................... 4-2
Komatsu Genuine Lubricants ............................................................................................................. 4-2
Always Use Clean Washer Fluid ........................................................................................................ 4-2
Clean Lubricants ................................................................................................................................ 4-2
Examine Drained Oil and Used Filter ................................................................................................. 4-2
Precautions When You Refill Oil or Fuel............................................................................................. 4-2
Precautions When You Add DEF ....................................................................................................... 4-2
Precautions for Welding ..................................................................................................................... 4-2
Do Not Drop Things Inside Machine................................................................................................... 4-2

1-10
Foreword Table of Contents

Burn Prevention ................................................................................................................................. 4-3

Dusty Jobsites.................................................................................................................................... 4-4
Avoid Mixing Oil ................................................................................................................................. 4-4
Precautions for Opening and Closing Radiator Grille ......................................................................... 4-4
Precautions When You Open Inspection Cover.................................................................................. 4-4
Lock Inspection Covers...................................................................................................................... 4-4
Bleed Air from Hydraulic System........................................................................................................ 4-4
Precautions When You Install Hydraulic Hoses .................................................................................. 4-4
Checks After Inspection and Maintenance ......................................................................................... 4-5
Select Fuel and Lubricants by Ambient Temperature ......................................................................... 4-5
Outline of Maintenance ............................................................................................................................. 4-6
Handle Oil, Fuel, Coolant, and Do Oil Clinic ....................................................................................... 4-6
Handle Electrical Components ..........................................................................................................4-11
Handle Hydraulic Components..........................................................................................................4-11
Standard Tightening Torque for Bolts and Nuts ....................................................................................... 4-12
Maintenance Schedule............................................................................................................................ 4-14
Maintenance Schedule Table ........................................................................................................... 4-14
Maintenance Interval When Diesel Fuel Mixed with Bio-Fuel is Used .............................................. 4-16
Maintenance Procedure .......................................................................................................................... 4-17
When Required ................................................................................................................................ 4-17
Examine Before You Start Operation................................................................................................ 4-54
Every 50 Hours Maintenance ........................................................................................................... 4-55
Every 250 Hours Maintenance ......................................................................................................... 4-56
Every 500 Hours Maintenance ......................................................................................................... 4-62
Every 1000 Hours Maintenance ....................................................................................................... 4-70
Every 2000 Hours Maintenance ....................................................................................................... 4-79
Every 4000 Hours Maintenance ....................................................................................................... 4-93
Every 4500 Hours Maintenance ....................................................................................................... 4-97
Every 8000 Hours Maintenance ....................................................................................................... 4-98
Every 9000 Hours Maintenance ....................................................................................................... 4-99
Specifications................................................................................................................................................... 5-1
Specifications............................................................................................................................................ 5-2
Specifications: D51EX-24 .................................................................................................................. 5-2
Specifications: D51PX-24 .................................................................................................................. 5-3
Attachments and Options ................................................................................................................................. 6-1
General Precautions ................................................................................................................................. 6-2
Precautions for Safety........................................................................................................................ 6-2
Handle Hydraulic Ripper ........................................................................................................................... 6-3
General View ..................................................................................................................................... 6-3
Explanation of Components ............................................................................................................... 6-4
Machine Operations and Controls ...................................................................................................... 6-7
Troubles and Procedures ................................................................................................................... 6-9
Examine and Maintenance............................................................................................................... 6-10
Every 250 Hours Maintenance ......................................................................................................... 6-10
Lubrication ....................................................................................................................................... 6-10
How to Examine Oil Level in Hydraulic Tank, Add Oil....................................................................... 6-10
Specifications: D51EX-24 .................................................................................................................6-11
Handle External Power Supply Engine Preheater ................................................................................... 6-12
Install External Power Supply System for External Power Supply Engine Preheater........................ 6-13
Make External Power Supply Cable ................................................................................................. 6-15
Install External Power Supply System .............................................................................................. 6-17
Examine Operation After You Assemble .......................................................................................... 6-19
How to Start Engine in Cold Weather ............................................................................................... 6-20
Replacement Parts........................................................................................................................................... 7-1
Periodic Replacement of Defined Life Parts .............................................................................................. 7-2
Defined Life Parts List ........................................................................................................................ 7-2
Consumable Parts .................................................................................................................................... 7-3
Consumable Parts List ....................................................................................................................... 7-3

1-11
Table of Contents Foreword

Recommended Fuel, Coolant, and Lubricant ............................................................................................ 7-4

Lubrication Chart................................................................................................................................ 7-4
How to Use Fuel, Coolant and Lubricants by Ambient Temperature................................................... 7-7
Recommended Brands and Qualities Other Than Komatsu Genuine Oils.......................................... 7-8
INDEX.............................................................................................................................................................. 8-1

1-12
 Safety

Please read and make sure that you fully understand the precautions descri-
bed in this manual and the safety labels on the machine. When operating or
servicing the machine, always follow these precautions strictly.

2-1
Safety Labels Safety

Safety Labels
k WARNING
Be sure that you fully understand the correct position, content and how to avoid a danger shown in the
safety labels.

Handle the warning signs and safety labels used on this machine as follows.
• Always keep the safety labels clean so that you can read it properly. When cleaning the safety labels, do
not use organic solvents or gasoline. These may cause the labels to peel off.
• If the safety labels are damaged, lost, or cannot be read properly, replace them with new ones. For details
of the part numbers for the safety labels, see this manual or the actual label, and place an order to your
Komatsu distributor.
• There are also other labels in addition to the warning signs and safety labels. Handle those labels in the
same way.

2-2
Safety Safety Labels

Location of Safety Labels

(1) Caution for operation, inspection and maintenance (10) Caution for approaching while moving machine
(2) Caution for safety at rear (11) Prohibition of start by short-circuiting
(3) Caution when leaving operator's seat (12) Caution for handling battery
(4) Caution for high-temperature coolant (13) Caution for handling ROPS/FOPS
(5) Caution for high-temperature oil (14) Caution for blast site
(6) Caution for handling accumulator (15) Caution when traveling in reverse
(7) Caution for adjusting track tension (16) Caution for handling DEF
(8) Caution for handling cable (17) Caution for handling seat belt
(9) Stop rotation during inspection and maintenance

2-3
Safety Labels Safety

Safety Labels
Caution for Operation, Inspection and Maintenance
“09651-03001”

Caution for Safety at Rear

“09802-13000”

2-4
Safety Safety Labels

Caution When You Move Away from the Operator Seat

“09654-33001”

Precautions for High-Temperature Coolant

“09668-03001”

Precautions for High-Temperature Oil

“09653-03001”

Caution for Handling Accumulator

“09659-53000”

2-5
Safety Labels Safety

Caution for Check and Adjust Track Tension

“09657-03003”
The safety label is attached to the back of the cover of the track
adjustment window.

Caution for Handling Cable

“09808-03001”

Stop Rotation During Inspection and Maintenance

“09667-43000”

Caution for approaching while moving machine

“11Y–98–51151”

DANGER
Stay clear
11Y-98-51151

2-6
Safety Safety Labels

Prohibition of Start by Short-circuiting

“09842-A0642”
• Start the engine only after sitting down in the operator’s
seat.
• Do not attempt to start the engine by shot-circuiting the en-
gine starting circuit. Such an act may cause a serious bodi-
ly injury or fire.

Caution for Handling Battery

“09664-30014”
DANGER
DANGER: Lead Acid Battery. Contains Lead, Sulfuric Acid and Lead Compounds.
WARNING: Risk of explosion, burn or fire. Do not disassemble.
High Voltage : Risk of shock, do not touch uninsulated terminals or connectors.
KEEP OUT OF REACH OF CHILDREN. KEEP VENT CAPS TIGHT AND LEVEL.
Open flames or sparks could cause battery to explode. May form explosive +
air/gas mixture during charging.Store and use in well-ventilated area.
Extremely flammable gas(hydrogen),Explosion,Fire,Blast or Projectile
hazard. Do not handle or charge until all safely precautions/instructions have
been read and understood.Wear protective gloves, protective clothing,eye
protection and face protection when handling. lf SWALLOWED,INHALED,
or IN EYE: immediately call a POISON CENTER or consult doctor/physician.
if on CLOTHES or SKIN: wash immediately with water.
Pb
Komatsu America Corp.1701 Golf Rd. Rolling Meadows,IL 60008.(731)635 6321
09664-30014

Caution for Handling ROPS/FOPS

“09620-A2001”, “09620–A2171”

Caution for Blast Site

“09845-13000”
(only when equipped with KOMTRAX)

2-7
Safety Labels Safety

Caution When Traveling in Reverse

“09833-33000”
(only machines equipped with camera)

Caution for Handling DEF

“09632–31800”

Caution for Handling Seat Belt

“09848-13000”

2-8
Safety General Precautions Common to Operation and Maintenance

General Precautions Common to Operation and Mainte-

nance
Mistakes in operation, inspection, or maintenance may result in serious personal injury or death. Before per-
forming operation, inspection, or maintenance, always read this manual and the safety labels on the machine
carefully and obey the warnings.

Precautions Before You Start Operation

For Safety Operation
• Only trained and authorized personnel can operate and maintain the machine.
• Follow all safety, precautions, and instructions in this manual when operating or performing inspection or
maintenance on the machine.
• If you are not feeling well, or if you are under the influence of alcohol or medication, your ability to safely
operate or repair your machine may be severely impaired, putting yourself and everyone else on your job
site in danger.
• When working with another operator or with the person on the worksite traffic duty, discuss the content of
the operation beforehand and use the determined signals when performing the operation.

Understand the Machine

Before operating the machine, read this manual thoroughly. If there is any place in this manual that you do not
understand, ask the person in charge of safety for explanation.

Prepare for Safety Operation

Precautions for Safety-related Equipment
• Be sure that all guards, covers, cameras, and mirrors are in their proper position. Repair them immediately
if they are damaged.
• Understand the using method of the safety related devices and use them properly.
• Never remove any safety related devices. Always keep them in good operating condition.

Inspect Machine
Check the machine before starting operations. If any abnormality is found, do not operate the machine until re-
pairs of the problem location have been completed.

Wear Well-Fitting Clothes and Protective Equipment

• Do not wear loose clothes or any accessories. If any of
these catch the control levers or protruding parts, it may
cause the machine to move unexpectedly, it is extremely
dangerous.
• Always wear a hard hat and safety shoes. Wear protective
eyeglasses, mask, gloves, ear plugs, and personal fall-ar-
rest equipment as appropriate for the work function.
• Long hair hanging out from the hard hat is dangerous that
it may get caught up in the machine. Tie the hair up and be
careful not to be caught.
• Check that all personal protective items function properly
before using them.

2-9
General Precautions Common to Operation and Maintenance Safety

Keep Machine Clean

• If you get on or off the machine or perform inspection and maintenance on the machine with mud or oil, you
may slip and fall, and it is dangerous. Wipe off any mud or oil from the machine. Always keep the machine
clean.
• If water gets into the electrical system, electric devices will
cause malfunctions, and the machine will cause error. If
the machine cause error, it may move unexpectedly and
cause serious personal injury or death. When washing the
machine with water or steam, do not allow the water or
steam to come into direct contact with electrical compo-
nents.
• If high-pressure water is sprayed directly onto camera, it
may cause failure. Do not allow the high-pressure water to
get into camera directly. When cleaning the camera, wipe
off any dirt with soft cloth.
• When cleaning camera, if you stand on an unstable place, or take an unstable posture, you may fall and be
injured. Put proper stepladder or step on the level and firm ground, and clean the camera in secure posture.

Precautions for Inside Operator's Compartment

• When entering the operator's compartment, always remove all mud and oil from the soles of your shoes.
If you operate the pedal with mud or oil affixed to your shoes, your foot may slip and this may cause a seri-
ous accident.
• Do not leave tools or machine parts lying around inside the operator's compartment. If tools or parts get into
the control devices, it may obstruct operation and cause the machine to move unexpectedly, resulting in
serious personal injury or death.
• Do not stick suction pads to the window glass. Suction pads act as a lens and may cause fire.
• Do not use a cellular phone when driving or operating the machine. This may lead to mistakes in operation,
and may cause serious personal injury or death.
• Never bring any dangerous objects such as flammable or explosive items into the operator's compartment.

Supply Fire Extinguisher and First Aid Kit

Observe the following precautions to prepare for action if any
serious personal injury or death or fire should occur.
• Be sure that fire extinguishers have been provided and
read the labels to ensure that you know how to use them
for the possibility of fires.
• Perform periodic inspection and maintenance to ensure
that the fire extinguisher can always be used.
• Provide a first aid kit in the storage point. Perform periodic
checks and add to the contents if necessary. ,&

If a Problem is Found
If you find any problem in the machine during operation or maintenance (noise, vibration, smell, incorrect
gauges, smoke, oil leakage, etc., or any abnormal display on the warning devices or monitor), report to the per-
son in charge and take the necessary action. Do not operate the machine until the problem has been corrected.

2-10
Safety General Precautions Common to Operation and Maintenance

Precautions to Prevent Fire

Procedures If Fire Occurs
• Turn the starting switch to OFF position, and stop the engine.
• Use the handrails and steps to escape from the machine.
• Do not jump off the machine. There is the danger of falling and it may cause personal injury.
• The fume generated by a fire contains harmful materials which have a bad influence on your body when
they are inhaled.
Do not breathe the fumes.
• After a fire, harmful compounds may be left. If it touches your skin, it may have a bad influence on your
body.
Be sure to wear rubber gloves when handle the materials left after the fire.
The material of the gloves, which is recommended is polychloroprene (Neoprene) or polyvinyl chloride (in
the lower temperature environment).
When wearing cotton work gloves, wear rubber gloves under them.

Prevent Fire
Fire Caused by Fuel, Oil, Coolant, or Window Washer Fluid
Do not bring any open flame close to flammable substances
such as fuel, oil, coolant, or window washer fluid. There is a
danger that they may catch fire. Always observe the following.
• Do not smoke or use any open flame near fuel or other
flammable substances.
• Shut down the engine before adding fuel.
• Do not leave the machine when adding fuel or oil.
• Tighten all the fuel and oil caps securely.
,&
• Be careful not to spill fuel on overheated surfaces or on
parts of the electrical system.
• After adding fuel or oil, wipe up any spilled fuel or oil.
• Put greasy rags and other combustible materials into a
safe container to maintain safety at the workplace.
• When washing parts with oil, use a non-flammable oil. Do
not use diesel fuel or gasoline. There is danger that they
may catch fire.
• Do not weld or use a cutting torch to cut any pipes or tubes
that contain combustible liquids. ,&
• Determine well-ventilated areas for storing oil and fuel.
Keep the oil and fuel in the specified place and do not allow unauthorized persons to enter.
• When performing grinding or welding work on the machine, move any flammable materials to a safe place
before starting.
Fire Caused by Accumulated or Attached Flammable Objects
• Remove any dry leaves, chips, pieces of paper, coal dust, or any other combustible materials accumulated
or affixed around the engine exhaust manifold, muffler, or battery, or inside the undercovers.
• To prevent fires from spreading sparks or burning particles from other fires, remove any combustible materi-
als such as dry leaves, chips, pieces of paper, coal dust, or any other combustible materials accumulated
around the cooling system (radiator, oil cooler) or inside the undercover.
Fire Caused by Electrical System
Short circuits in the electrical system can cause fire. Always observe the following.

2-11
General Precautions Common to Operation and Maintenance Safety

• Keep all the electric wiring connections clean and securely tightened.
• Check the wiring every day for looseness or damage. Reconnect any loose connectors or refasten wiring
clamps. Repair or replace any damaged wiring.
Fire from Pipings
Check that all the hose and tube clamps, guards, and cushions are securely fixed in position.
If they are loose, they may vibrate during operation and rub against other parts. There is danger that this may
lead to damage to the hoses and cause high-pressure oil to spurt out, leading to fire and serious personal injury.
Fire Caused by High Temperature Exhaust Gas
This machine is equipped with the exhaust gas aftertreatment devices which purify the exhaust gas.
During the aftertreatment devices regeneration, avoid getting near the exhaust pipe outlet and around the after-
treatment devices to prevent being burnt. Also, keep combustible materials away from the exhaust pipe outlet
and around the aftertreatment devices to prevent a fire.
When there are thatched houses, dry leaves or pieces of paper near the job site, stop the regeneration before
starting the work in order to prevent fire hazards due to highly heated exhaust gas during the aftertreatment de-
vices regeneration.
Explosion Caused by Light
When checking fuel, oil, battery electrolyte, or coolant, always use lighting with anti-explosion specifications.

2-12
Safety General Precautions Common to Operation and Maintenance

Precautions When You Get on or Off Machine

Use Handrails and Steps When You Get on or Off Machine
To prevent personal injury caused by slipping or falling off the machine, always observe the following.
• Use the handrails and steps indicated by arrow A in the figure when getting on or off the machine.
Use the handrails and steps indicated by arrow B only
when moving along the top of the track or when checking
or performing maintenance inside the side cover, or when
filling the tank with oil. Never use them when getting on or
off the machine.

• Always face the machine and maintain at least three-point

contact (both feet and one hand, or both hands and one
foot) with the handrails and steps to ensure that you sup-
port yourself.
• Before getting on and off the machine, check the handrails
and steps if there is any oil, grease, or mud on them. Wipe
it off immediately not to slip if any. In addition, tighten any
loose bolt of the handrails and steps.
If the handrails and steps are damaged or deformed, they
need to be repaired immediately. Ask your Komatsu dis- ,&
tributor to perform this work.
• Do not grip the control levers and work equipment lock lever when getting on or off the machine. When get-
ting on or off the machine, take care that your body or clothes do not touch the control levers.
• Never climb on the engine hood or covers where there are no non-slip pads.
• Do not get on or off the machine with tools in your hand.

Do Not Jump On or Off Machine

Getting on or off the moving machine can cause serious personal injury or death. Always observe the following.
• Never jump on or off the machine. Never get on or off a moving machine.
• If the machine starts to move when there is no operator on the machine, do not jump on to the machine and
try to stop it.

No People on Attachments
Never let anyone ride on the work equipment or other attachments. There is a hazard of falling and suffering
serious personal injury or death.

2-13
General Precautions Common to Operation and Maintenance Safety

Precautions When You Stand Up from Operator's Seat

When standing up from the operator's seat to adjust the opera-
tor's seat, operate the work equipment lock lever (1) and park-
ing brake lever (2) by holding the operating portions on the top
to set the levers in LOCK position (L), and stop the engine.
If the control levers are touched by mistake, there is danger
that the machine may suddenly move and cause serious per-
sonal injury or death.

Precautions When You Move Away from Operator Seat

If the proper procedures are not taken when parking the machine, the machine may suddenly move off by itself,
and this may lead to serious personal injury or death. Observe the following.
• When leaving the machine, always lower the work equip-
ment to the ground, operate the work equipment lock lever
(1) and parking brake lever (2) by holding the operating
portions on the top to set the levers in LOCK position (L),
and stop the engine.
• Lock all the places and always take the key with you and
keep it in the specified place.

Emergency Exit from Operator Cab

The machine equipped with the cab has the doors on its right and left sides. If either door does not open, es-
cape from the other door.

Do Not Get Caught

The clearance in the area around the work equipment changes according to the movement of the link. If you are
caught, this may lead to serious personal injury or death. Do not allow anyone near any of the rotating or tele-
scopic parts.

2-14
Safety General Precautions Common to Operation and Maintenance

Precautions Related to Protective Structures

The operator's compartment is equipped with a structure (such as ROPS, FOPS) to protect the operator by ab-
sorbing the impact energy.
As for the machine equipped with ROPS, if the machine weight
(mass) exceeds the certified value (shown on ROLL-OVER
PROTECTIVE STRUCTURE (ROPS) CERTIFICATION plate),
ROPS will not be able to fulfill its function. Do not increase ma-
chine weight beyond the certified value by modifying the ma-
chine or by installing attachments to the machine.
Also, if the function of the protective equipment is impeded, the
protective equipment will not be able to protect the operator,
and the operator may suffer injury. Always observe the follow-
ing. ,&

• If the machine is equipped with a protective structure, do

not remove the protective structure and perform operations without it.
• If the protective structure is welded, or holes are drilled in it, or it is modified in any other way, its strength
may drop. Any modification is prohibited.
• If the protective structure is damaged or deformed by falling objects or by rolling over, its strength will be
reduced and it will not be able to fulfill its function properly. In such cases, always consult your Komatsu
distributor.
• Even if the protective structure is installed, always fasten your seat belt properly when operating the ma-
chine. If you do not fasten your seatbelt properly, it cannot display its effect.
Always fasten your seat belt while operating the machine.

Unauthorized Modification
• Komatsu will not be responsible for any personal injuries, product failures, physical loss or damage, or influ-
ence on the environment resulting from modifications made without authorization from Komatsu.
• Any modification made without authorization from Komatsu can create hazards. Before making a modifica-
tion, consult your Komatsu distributor.

Precautions Related to Attachments and Options

• Any personal injuries, product failures, physical loss or damage, or influence on the environment resulting
from the use of unauthorized attachments or parts will not be the responsibility of Komatsu.
• When installing optional parts or attachments, contact your Komatsu distributor for advice to any potential
problems or safety and legal requirements.
• When installing and using optional attachments, always read the instruction manual for the attachment, and
the general information related to attachments in this manual.

Precautions When You Operate Engine Inside Building

The engine exhaust gas contains substances that may damage
your health or even cause death. Start or operate the engine in
a place where there is good ventilation. If the engine or ma-
chine must be operated inside a building or underground,
where the ventilation is poor, take steps to ensure that the en-
gine exhaust gas is removed and that ample fresh air is
brought in.

,&

2-15
Precautions for Operation Safety

Precautions for Operation

Precautions for Jobsite
Examine Jobsite Conditions
On the jobsite, there are various hidden dangers that may lead to serious personal injury or death. Before start-
ing operations, always check the following to confirm that there is no danger on the jobsite.
• Always be careful when performing operations near materials such as thatched houses, dry leaves or dry
grass, because they are easily combustible and may cause fire.
• Check the terrain and condition of the ground at the jobsite, and determine the safest method of operation.
Do not operate in a dangerous area where landslides or rockfall may occur.
• If water lines, gas lines, or high-voltage electrical lines may
be buried under the jobsite, contact the management com-
pany to identify their locations, and be careful not to dam-
age any of these lines.
• Take necessary measures to prohibit other personnel from
coming close to the machine during operation.
• In particular, if you need to operate on a road, protect pe-
destrian and cars by designating a person for jobsite traffic
duty or by installing fences around the jobsite.
• When traveling or operating in shallow water or on soft
ground, check the water depth, speed of the current, con-
dition of bedrock, and shape of the ground beforehand. Always avoid any place that will obstruct travel.

Precautions When You Work on Loose Ground

• Avoid driving or operating the machine near the edge of cliffs, road edges, and deep ditches. The ground
may be weak in such areas. If the ground should collapse under the weight or vibration of the machine,
there is a hazard that the machine may fall or tip over. Remember that the soil is weak in these areas, after
heavy rain or blasting or after earthquakes.
• When working on embankments or near excavated ditches, there is a hazard that the weight and vibration
of the machine will cause the soil to collapse. Before starting operations, take steps to ensure that the
ground is safe and to prevent the machine from rolling over or falling.

2-16
Safety Precautions for Operation

Do Not Go Close to High-Voltage Cables

Do not travel or operate the machine near electric cables. There is a hazard of electric shock, which may cause
serious personal injury or death. On jobsites where the machine may go close to electric cables, always observe
the following.
• Before starting work near electric cables, inform the local
power company of the work to be performed, and ask
them to take the necessary action.
• Even going close to high-voltage cables can cause electric
shock. Always maintain a safe distance (see the table) be-
tween the machine and the electric cable. Check with the
local power company about the voltage of cables and safe
operating procedure before starting operations.
VOLTAGE MIN. DISTANCE
50 kV or Less 3.1 m {10 ft}
50 kV to 200 kV 4.6 m {15 ft}
200 kV to 350 kV 6.1 m {20 ft}
350 kV to 500 kV 7.7 m {25 ft}
500 kV to 750 kV 10.7 m {35 ft}
750 kV to 1000 kV 13.8 m {45 ft}
• To prepare for any possible emergencies, wear rubber shoes and gloves. Lay a rubber sheet on the opera-
tor's seat, and be careful not to touch the chassis with any exposed part of your body.
• Use a signalman to give warning if the machine approaches too close to the electric cables.
• When performing operations near high voltage cables, prohibit anyone other than related persons to come
close to the machine during operation.
• If the machine should come too close or touch the electric cable, to prevent electric shock, the operator
should not leave the operator's compartment until it has been confirmed that the electricity has been shut
off. Also, prohibit any other persons to come close to the machine.

Make Sure of Good Visibility

Although this machine is equipped with mirrors and cameras to ensure good visibility, there are places that can-
not be seen from the operator's seat. Be careful when performing operation.
When driving the machine or performing operations in places with poor visibility, it is dangerous and may cause
serious personal injury or death because it is difficult to check for obstacles and condition of the jobsite. When
driving the machine or performing operations in places with poor visibility, always observe the following.
• Allocate a signalman for jobsite duty if there are areas where the visibility is poor.
• Only one signalman should give signals.
• When working in dark places, turn on the working lamp and headlamps installed to the machine, and set up
additional lighting in the work area if necessary.
• Stop operations if the visibility is poor because of mist, snow, rain, or dust.
• When checking the mirrors installed to the machine, remove all dirt and adjust the angle of the mirror to
ensure good visibility.
• When cleaning the camera, wipe off any dirt with soft cloth. Make sure that a clear view is displayed on the
monitor.
When cleaning camera, if you stand on an unstable place, or take an unstable posture, you may fall and be
injured. Put proper stepladder or step on the level and firm ground, and clean the camera in secure posture.

2-17
Precautions for Operation Safety

See Signs and Signalman's Signals

If signals and labels are not clear, serious personal injury can result from downward slip, overturn or accidental
contact with nearby people or obstacles. Always observe the following.
• Set up labels to inform of road edges and soft ground. If the visibility is not good, position a conductor if
necessary. Operator should pay careful attention to the labels and follow the instructions from the conduc-
tor.
• Only one signalman should give signals.
• Make sure that all workers understand the meaning of all signals, signs, and labels before starting work.

Be careful of Asbestos Dust

Asbestos dust in the air can cause lung cancer if it is inhaled.
There is danger of inhaling asbestos when working on jobsite
where demolition work is performed or industrial waste is han-
dled. Always observe the following.
• Spray water to keep down the dust.
• Do not use compressed air.
• If there is danger that there may be asbestos dust in the
air, always operate the machine from an upwind position,
and make sure that all workers operate on the upwind ,&
side.
• All workers should use anti-dust masks.
• Prohibit other personnel from coming close to the machine during operation.
• Always observe the regulations for jobsite and environmental standards.
This machine does not contain asbestos, but any part which is not the genuine part, it has risk of containing
asbestos. Always use Komatsu genuine parts.

2-18
Safety Precautions for Operation

Start Engine
Use Warning Tags
If there is a “DANGER! Do NOT operate!” warning tag dis-
played, it means that someone is performing inspection and
maintenance of the machine. If the warning tag is ignored and
the machine is operated, the person performing inspection or
maintenance may be caught in the rotating parts or moving
parts. It is dangerous and may cause serious personal injury or
death. Do not start the engine or touch the levers.

Checks and Adjustment Before You Start Engine

Perform the following checks before starting the engine at the beginning of the day's work to ensure that there is
no problem with the operation of the machine. If these checks are not performed properly, problems may occur
with the operation of the machine, and there is a danger which may lead to serious personal injury or death.
• Remove all dirt from the surface of the window glass to ensure a good view.
• Perform the walk-around check.
• Remove all dirt from the surface of the lens of the headlamps and working lamps, and check that they light
up correctly.
• Check the coolant level, fuel level, DEF level, and oil level in engine oil pan, check for clogging of the air
cleaner, and check for damage to the electric wiring.
• Check the battery terminals for looseness or corrosion.
• Check that there is no mud or dust accumulated around the movable parts of any pedals, and check that
the pedals work properly.
• Adjust the operator's seat to a position for easier operation. Check that there is no damage or wear to the
seat belt or mounting clamps.
• Check that the gauges work properly, check the angle of the mirror, and check that the control levers are all
at NEUTRAL position.
• Before starting the engine, check that work equipment lock
lever (1) and parking brake lever (2) are in LOCK positions
(L).
• Adjust the mirrors to have a good rear view from the oper-
ator's seat.
• Check that there is no person or obstacle above, below, or
in the area around the machine.

2-19
Precautions for Operation Safety

Precautions When You Start Engine

The machine may suddenly move off and this may lead to serious personal injury or death. Always observe the
following.
• Start the engine only while sitting down in the operator's seat.
• When starting the engine, sound the horn as a warning.
• Prohibit other personnel to get on the machine.
• Do not attempt to start the engine by short-circuiting the engine starting circuit. This may cause fire, serious
personal injury or death.

In Cold Weather
• If the warm-up operation is not performed thoroughly, and the work equipment is operated, the reaction of
the work equipment to the operation of the control levers and pedals will be slow and the movement of it
may not be what the operator intended. Be sure to perform the warm-up operation. Particularly in a cold
weather, be sure the warming-up operation is completed.
• If the battery electrolyte is frozen, do not charge the battery or start the engine with a different power
source. There is a hazard that this will ignite the battery and cause the battery to explode.
Before charging or starting the engine with a different power source, melt the battery electrolyte and check
that there is no leakage of electrolyte before starting.

Start Engine with Jumper Cables

If any mistake is made in the method of connecting the jumper cables, it may cause the battery to explode, so
always observe the following.
• Always wear protective eyeglasses and rubber gloves
when starting the engine by using the jumper cables.
• When connecting a normal machine to a failed machine
with the jumper cables, always use the normal machine
with the same battery voltage as the failed machine.
• When starting the engine with the jumper cables, perform
the starting operation with 2 workers (one worker sitting in
the operator's seat and the other working with the battery).
• When starting from another machine, be careful that the
normal machine does not contact with the failed machine.
• When connecting the jumper cables, turn the starting
switch to OFF position for both the failed machine and the normal machine. If the failed machine has a bat-
tery disconnect switch, turn it to OFF position, and turn it ON again after connecting the cables.
It is dangerous that the machine may move when the power is connected.
• Be sure to connect the positive (+) cable first when installing the jumper cables. Disconnect the negative (-)
cable (ground side) first when removing them.
• When disconnecting the jumper cables, take care not to bring the clips in contact with each other or with the
machine.

2-20
Safety Precautions for Operation

Precautions for Operation

Checks Before Operation
If the checks before starting are not performed properly, the machine will be unable to display its full perform-
ance. It is dangerous and may cause serious personal injury or death.
When performing the checks, move the machine to a wide area with no obstructions, and pay careful attention
to the surroundings. Prohibit other personnel from coming close to the machine during checks.
• Fasten the seatbelt. When the brakes are applied sudden-
ly, the operator may be thrown out of the operator's seat. It
is dangerous and may cause personal injury.
• Check the operating condition of the machine, work equip-
ment, and travel and brake systems.
• Check for any problem in the sound, vibration, heat and
smell of the machine, or abnormalities of instruments. Also
check that there is no leakage of oil or fuel.
• If any problem is found, repair it immediately.

Precautions When You Travel in FORWARD and REVERSE

• All the windows on the operator's cab must be fixed securely whether they are opened or closed.
In the jobsite where there is danger of objects that fly on or go in the operator's cab, close all the windows.
• Prohibit other personnel to get on the machine.
• If there are any persons in the area around the machine,
there is danger that they may be hit or caught by the ma-
chine, and this may lead to serious personal injury or
death. Always observe the following before traveling.
• Always operate the machine only when seated on the
operator's seat.
• Before starting to move, check again that there is no
people or obstacle in the surrounding area.
• Before moving, sound the horn to warn people in the
surrounding area.
• Check that the backup alarm (alarm buzzer when machine travels in reverse) works properly.
• If there is an area in the rear of the machine which cannot be seen, position a signalman. Travel slowly
and be extremely careful not to hit any person or object.
Always be sure to perform the above precautions even when the machine is equipped with mirrors and cam-
eras.

2-21
Precautions for Operation Safety

Precautions When You Travel

Serious personal injury or death can result from tipping over of the traveling machine or its accidental contact.
Always observe the following.
• When driving the machine or performing operations, always keep a safe distance from people, structures,
or other machines to avoid coming into contact with them.
• Never turn the key in the starting switch to OFF position when the machine is traveling. If the engine stops
when the machine is traveling, it may become impossible to operate the steering, and this may cause seri-
ous personal injury or death. If the engine stops, depress the decelerator/brake pedal immediately to stop
the machine.
• When driving the machine on a level ground, keep the
work equipment at height (A) of 40 to 50 cm {16 to 20 in}
above the ground. If that height is not maintained between
the work equipment and the ground, the work equipment
may get stuck in the ground and the machine may tip over.

• Try to avoid traveling over obstacles. If the machine has to

travel over an obstacle, keep the work equipment close to
the ground and travel at low speed. The machine tips over
easily to the right or left. Do not drive it over obstacles
which make the machine tilt largely to the right or left.
• When driving the machine on the rough ground, drive it at
low speed and do not operate the steering suddenly. There
is a danger that the machine may tip over. The work equip-
ment may hit the ground, and the machine may lose its
balance, or it may damage the machine or structures in the
area.
• When using the machine, to prevent serious personal injury or death caused by the work equipment or by
the machine tipping over due to overloading, do not use the machine beyond the permitted performance of
the machine such as the maximum permitted load for the structure of the machine.
• When passing over bridges or structures, check first that the structure is strong enough to support the
weight of the machine.
• When operating in tunnels, under bridges, under electric wires, or other places where the height is limited,
operate slowly and be extremely careful not to let the machine body or work equipment hit anything.

2-22
Safety Precautions for Operation

Precautions When You Travel on Slopes

To prevent the machine from tipping over or slipping to the side, always observe the following.
• Never turn the key in the starting switch to OFF position
when the machine is traveling downhill. If the engine stops
when the machine is traveling, it may become impossible
to operate the steering, and this may cause serious per-
sonal injury or death. If the engine stops, depress the de-
celerator/brake pedal immediately to stop the machine.
• Keep the work equipment approximately 20 to 30 cm {8 to
12 in} above the ground. In case of emergency, lower the
work equipment to the ground immediately to help stop the
machine.
• Always drive the machine straight up or down a slope.
Driving the machine at an angle or across the slope is extremely dangerous.
• Do not turn on slopes or drive across slopes. Always go down to a flat place to change the position of the
machine, then drive it on to the slope again.
• Do not drive the machine on a slope covered with the steel plates. Even with slight slopes there is a hazard
that the machine may slip.
• Drive the machine at low speed on the grass or fallen leaves. Even with slight slopes, there is a hazard that
the machine may slip.
• Depress the brake pedal or use the engine brake as necessary.

Precautions When You Operate Machine

• Be careful not to approach too close to the edge of cliffs. When making embankments or landfills, or when
dropping soil over a cliff, dump one pile, then use the next pile of soil to push the first pile.
• The load suddenly becomes lighter when the soil is pushed over a cliff or when the machine reaches the
top of a slope. When this happens, there is danger that the travel speed will suddenly increase, so be sure
to reduce the speed.
• If the machine moves with only either side of the blade loaded, its tail may swing. Take care.

Prohibited Operations
When using the machine, to prevent serious personal injury or death caused by the work equipment or by the
machine tipping over due to overloading, do not use the machine beyond the permitted performance of the ma-
chine such as the maximum permitted load for the structure of the machine.

How to Use Brakes

When driving the machine downhill, use the decelerator/brake pedal to reduce the travel speed.

2-23
Precautions for Operation Safety

Precautions When You Operate on Snow or Frozen Surfaces

• Snow-covered or frozen surfaces are slippery, so be extremely careful when traveling or operating the ma-
chine, and do not perform abrupt lever operation. Machine may slip even on a slight slope. Be particularly
careful when working on slopes.
• Frozen road becomes soft when the temperature rises, and the machine may tip over or be not able to es-
cape. Be particularly careful when working on frozen road.
• It is dangerous that the machine enters deep snow. The machine may tip over or become buried in the
snow. Be careful not to go off the road or to get trapped in a drift of snow.
• When performing snow removal, the road and objects placed beside the road are buried in the snow and
cannot be seen. Be careful.
• When traveling on snow-covered slopes, never apply the foot brake suddenly. Reduce the speed and use
the engine brake while applying the foot brake intermittently (depress the brake intermittently several
times). If necessary, lower the work equipment to the ground to stop the machine.

Precautions When You Park Machine

Unexpected move of the parked machine can cause serious personal injury or death. Always observe the fol-
lowing.
• Park the machine on a firm, level ground.
• Select a place where there is no hazard of landslides, falling rocks, or flooding.
• Lower the work equipment to the ground.
• When leaving the machine, always lower the work equip-
ment to the ground, operate the work equipment lock lever
(1) and parking brake lever (2) by holding the operating
portions on the top to set the levers in LOCK position (L),
and stop the engine.
• Always close the operator's cab door, and use the key to
lock all the equipment in order to prevent any unauthorized
person from operating the machine. Always remove the
key, take it with you, and keep it in the specified place.

• If it is necessary to park the machine on a slope, always

observe the following.
• Set the work equipment on the downhill side and dig it
into the ground.
• In addition, block the tracks from movement.

2-24
Safety Precautions for Operation

Precautions for Transportation

When the machine is transported on a trailer, serious personal injury or death may result because of the acci-
dent during transportation. Always observe the following.
• Always check the machine dimensions carefully. Depending on the work equipment and optional devices
installed, the machine weight, transportation height, and overall length differ.
• Check beforehand that all bridges and other structures on the transportation route are strong enough to
withstand the combined weight of the transporter and the machine being transported.
• This machine may need to be divided into components for transportation depending on the regulation.
When transporting the machine, consult your Komatsu distributor.

Precautions When You Load and Unload

If handling is wrong when loading or unloading the machine, it is dangerous that the machine may tip over or
fall. It requires particular attention. Always observe the following.
• Perform loading and unloading on a firm, level ground only. Avoid road edge or place near the cliff.
• Always use ramps of adequate strength. Be sure that the
ramps are wide, long, and thick enough to provide a safe
loading slope. Take suitable steps to prevent the ramps
from moving out of position or coming off.
(1) Chocks
(2) Ramp
(3) Center of ramp
(4) Angle of ramp: Max. 15 °.
• Be sure the ramp surface and the platform of trailer are
clean and free of grease, oil, ice, water and other loose
materials. If any, remove them. Remove dirt around the undercarriage of the machine. On a rainy day, in
particular, be extremely careful since the ramp surface is slippery.
• Run the engine at low idle and drive the machine slowly at low speed.
• When on the ramps, do not operate any lever except for the travel lever (travel forward and reverse).
• Never correct your steering on the ramps. If necessary, drive off the ramps onto the ground, correct the di-
rection, then enter the ramps again.
• The center of gravity of the machine will change suddenly at the joint between the ramps and the loading
platform, and there is danger of the machine losing its balance. Drive slowly over this point.
• When loading or unloading to an embankment or platform, make sure that it has suitable width, strength,
and grade.
• For machines equipped with a cab, always lock the door after loading the machine. The door may open
during transportation.
• When it is necessary to remove handrails and steps, take care not to lose removed handrails and steps.
Install the removed handrails and steps securely.

2-25
Precautions for Operation Safety

Towing and being Towed

Precautions When You Tow and are Towed
Always use the correct towing equipment and towing method. Any mistake in the selection of the wire rope or
drawbar or the method of towing a disabled machine and being towed may lead to serious personal injury or
death.
• Make sure that the towing wire rope and towing bar have the strength at least 1.5 times the working weight
of the machine to be towed.
• Never use the wire rope which has cut strands (A), re-
duced diameter (B), or kinks (C). There is a danger that
the rope may break during the towing operation.
• Always wear leather gloves when handling the wire rope.
• Never tow a machine on a slope.
• During the towing operation, never stand between the tow-
ing machine and the machine being towed.

2-26
Safety Precautions for Maintenance

Precautions for Maintenance

Precautions Before Inspection and Maintenance
Show Warning Tag During Inspection and Maintenance
During inspection and maintenance, always display the “DAN-
GER! Do NOT operate!” warning tag.
If there is a “DANGER! Do NOT operate!” warning tag dis-
played, it means that someone is performing inspection and
maintenance of the machine. If the warning tag is ignored and
the machine is operated, the person performing inspection or
maintenance may be caught in the rotating parts or moving
parts. It is dangerous and may cause serious personal injury or
death. Do not start the engine or touch the levers.
If necessary, put up signs around the machine as well.
Warning tag part No. 09963-03001
When not using this warning tag, keep it in the toolbox. If there
is no toolbox, keep it in the pocket for Operation and Mainte-
nance Manual.

Keep Work Place Clean

Do not leave hammers or other tools lying around in the work place. Wipe up all grease, oil, or other substances
that will cause you to slip. Always keep the work place clean the tidy to enable you to perform operations safely.
If the work place is not kept clean and tidy, there is the danger that you will trip, slip, or fall over and injure your-
self.

Select Correct Area for Inspection and Maintenance

• Stop the machine on a firm, level ground.
• Select a place where there is no hazard of landslides, falling rocks, or flooding.

Only Authorized Personnel

As long as maintenance of the machine is continued, do not allow unauthorized person to come near the work-
place. They might get unexpected personal injury from, for instance, touching machine. Do not allow anyone
except the workers concerned to enter the workplace. If necessary, employ a guard.

Assign Leader When You Work with Others

When repairing the machine or when removing and installing the work equipment, appoint a leader and follow
his/hers instructions during the operation in order to prevent personal injuries caused by being caught or
pinched.

2-27
Precautions for Maintenance Safety

Stop Engine Before You Inspect or Do Maintenance

If you are caught or pinched between the work equipment during operation, or exposed to high-temperature or
high-pressure liquids, it is dangerous and may cause serious personal injury or death. Always observe the fol-
lowing.
• Lower the work equipment to the ground and stop the en-
gine before performing any inspection and maintenance.

• Turn the starting switch to ON position, operate the work

equipment lock lever (2) by holding the operating portion
on the top to set the lever in FREE position (F), operate
the blade control lever and the ripper control lever to
RAISE and LOWER position 2 to 3 times repeatedly to re-
lease the remaining pressure in the hydraulic circuit, then
operate the parking brake lever (1) and work equipment
lock lever (2) by holding the operating portions on the top
to set the levers in LOCK position (L).
• Check that the battery relay is off and main power is not
conducted. (After turning the starting switch to OFF posi-
tion, wait for approximately 1 minute and press the horn switch. If the horn does not sound, power is not
conducted.)
• Block the tracks from movement.

2-28
Safety Precautions for Maintenance

Two Workers are Required for the Maintenance When the Engine is in Opera-
tion
To prevent accident, do not perform maintenance with the engine running. When it is necessary to perform the
maintenance with the engine running, always observe the following.
• One worker must always sit in the operator's seat and be ready to stop the engine at any time. All workers
must maintain contact with the other workers.
• Rotating parts such as the fan, fan belt are dangerous that
they may easily catch a body part or an object someone
wears. Be careful not to come close to the rotating part.
• Never drop or insert tools or other objects into the fan, fan
belt, or other rotating parts. They may contact the rotating
parts and break, and be scattered. It is dangerous.
• Stop the regeneration of the aftertreatment devices during
the maintenance.
,&

• Operate the work equipment lock lever (1) and parking

brake lever (2) by holding the operating portions on the
top, and set the levers in LOCK position (L) to prevent the
work equipment from moving.
• Do not touch the control levers. When it is necessary to
operate the control levers, always give a signal to your fel-
low workers to evacuate them to a safe place.

Precautions When You Install, Remove, or Store Attachments

• Appoint a leader before starting removal or installation operations for attachments.
• Place attachments that have been removed from the ma-
chine in a stable condition so that they do not fall. And take
steps to prevent unauthorized persons from entering the
storage area.

,&

Precautions When You Work at High Places

When working at high places, use a step ladder or other stand to ensure that the work can be performed safely.
There is a danger falling from high place that can lead to serious personal injury or death.

2-29
Precautions for Maintenance Safety

Precautions When You Work on Machine

• When performing maintenance work on the machine,
maintain the foothold clean and orderly to prevent falling.
Always observe the followings.
• Avoid spilling of oil and grease.
• Do not litter the tools.
• Watch your step when walking around on the ma-
chine.
• Remove mud and greases stuck to the shoe sole.
• Never jump down from the machine. When getting on and
off the machine, always face the machine and maintain at least three-point contact (both feet and one hand,
or both hands and one foot) with the handrails and steps to ensure that you support yourself.
• You must walk along the access aisle for checking being paved with non-slip pads. Never climb on the en-
gine hood and cover to prevent personal injuries from falling or failing over due to losing your footing.

Precautions When You Work Under Machine or Work Equipment

Machine or work equipment may fall, and it is dangerous that serious personal injury or death may occur. Al-
ways observe the following.
• Make sure the hoists or hydraulic jacks you use are in good condition and strong enough to handle the
weight of the component. Never use hydraulic jacks at places where the machine is damaged, bent, or twis-
ted. Never use if the element wire of wire rope is frayed, twisted or pinched. Never use bent or distorted
hooks.
• It is extremely dangerous to work under the machine if the
track shoes are lifted off the ground and the machine is
supported only with the work equipment. If any of the con-
trol levers is touched by accident, or there is damage oc-
curring to the hydraulic piping, the work equipment or the
machine will suddenly fall. Never work under the work
equipment or the machine.
• If it is necessary to raise the work equipment or the ma-
chine and then go under it to perform inspection or mainte-
nance, support the work equipment and machine securely ,&
with blocks and stands strong enough to support the
weight of the work equipment and machine.
If the work equipment and machine are not supported, they may come down and it may cause serious per-
sonal injury or death.
• Never use concrete blocks for supports. Concrete blocks may break under even light loads.

Use Applicable Tools

Use the tools suited to the task and use them correctly. Using
damaged, deformed, or low quality tools, or making improper
use of the tools may cause serious personal injury or death.

,&

2-30
Safety Precautions for Maintenance

Precautions for Check and Maintenance

Turn Battery Disconnect Switch to OFF Position
In the following cases, turn the starting switch to OFF position and check that the system operating lamp is off.
Then set the battery disconnect switch to OFF position and remove the switch key.
If you check and handle battery without turning battery disconnect switch to OFF position, serious personal in-
jury or death by such as an electric shock may occur.
• When storing the machine for a long time (more than 1 month)
• When repairing the electrical system
• When performing electric welding
• When handling the battery
• When replacing the fuse, etc.

Precautions for Welding

Welding operations must always be performed by a qualified welder and in a place equipped with proper equip-
ment. There is a hazard of gas, fire, or electric shock when performing welding, so never allow any unqualified
person to perform welding.

Handle Battery
Before inspecting or handling the battery, turn the key in the starting switch to OFF position and check that the
system operating lamp is off. Then set the battery disconnect switch to OFF position and remove the switch key.
Danger of Battery Exploding
When the battery is being charged, flammable hydrogen gas is generated and may explode. In addition, the bat-
tery electrolyte includes dilute sulphuric acid. Any mistake in handling may cause serious personal injury, explo-
sion, or fire, so always observe the following.
• Do not use or charge the battery if the battery electrolyte is below LOWER LEVEL mark. This may cause
an explosion. Always perform periodic inspection of the battery electrolyte level, and add purified water
(such as a commercial battery fluid) to UPPER LEVEL mark.
• Do not use a direct air blow or dry cloth to clean the battery. A wet cloth will prevent fire or explosion from
static electricity.
• Do not smoke or bring any open flame close to the battery.
• Hydrogen gas is generated when the battery is being
charged, so remove the battery from the machine, take it
to a well-ventilated place, remove the battery caps, then
perform the charging.
• After charging, tighten the battery caps securely.

2-31
Precautions for Maintenance Safety

Risk Caused by Dilute Sulfate

When the battery is being charged, flammable hydrogen gas is
generated and may explode. In addition, the battery electrolyte
includes dilute sulphuric acid. Any mistake in handling may
cause serious personal injury, explosion, or fire. Always ob-
serve the following.
• When handling the battery, always wear protective eye-
glasses and rubber gloves.
• If battery electrolyte gets into your eyes, immediately wash
your eyes with large amounts of fresh water. After that, get
,&
medical attention immediately.
• If battery electrolyte gets on your clothes or skin, wash it
off immediately with large amounts of water.
Danger of Sparks
Sparks may be generated and they can cause a fire. Always observe the following.
• Do not let tools or other metal objects make any contact between the battery cables. Do not leave tools
lying around near the battery.
• When removing the battery cables, turn the starting switch to OFF position and, after checking that the sys-
tem operating lamp goes out, set the battery disconnect switch key to OFF position and pull it out.
When removing the battery cables, remove the ground cable (negative (-) cable) first. When installing, con-
nect the positive (+) cable first, then connect the ground.
• Tighten the battery cable terminals securely.
• Secure the battery firmly in the specified position.

Precautions When You Use Hammer

When using a hammer, pins may come out or metal particles may be scattered. It is dangerous and may cause
serious personal injury or death. Always observe the following.
• When hitting pins or bucket teeth, broken pieces may be scattered, and it may cause personal injury to the
people in the surrounding area. Always check that there is no one in the surrounding area.
• If hard metal parts such as pins, bucket teeth, cutting
edges, or bearings are hit with a hammer, pieces might be
scattered, and it may cause serious personal injury or
death. Always wear protective eyeglasses and gloves.
• If the pin is hit with strong force, it may come out, and in-
jure people in the surrounding area. Do not allow anyone
to enter the surrounding area.

,&

Precautions for High-Temperature Coolant

To prevent burns from boiling water or steam spurting out when
checking or draining the coolant, wait for the coolant to cool
down to a temperature where the radiator cap can be touched
by hand. Then loosen the cap slowly to release the pressure in-
side the radiator, and remove the cap.

2-32
Safety Precautions for Maintenance

Precautions for High-Temperature Oil

To prevent burns from hot oil spurting out or from touching
high-temperature parts when checking or draining the oil, wait
for the oil to cool down to a temperature where the cap or plug
can be touched by hand. Then, loosen the cap or plug slowly to
release the internal pressure and remove the cap or plug.

Precautions for High-Temperature Areas

To prevent burns from touching high-temperature parts, when checking or performing maintenance after stop-
ping engine, check the parts have been cooled down to touch with bare hand before checking or maintenance.

Precautions for High-Pressure Oil

The hydraulic system is always under internal pressure. In addition, the fuel piping is also under internal pres-
sure when the engine is running and immediately after the engine is stopped. When performing inspection or
replacement of the piping or hoses, check that the internal pressure in the circuit has been released. If this is not
done, serious personal injury or death may result. Always observe the following.
• Do not perform inspection or replacement work with the circuit under pressure.
• If there is any leakage from the piping or hoses, the surrounding area may be wet, so check for cracks in
the piping and hoses and for swelling in the hoses.
When performing inspection, wear protective equipment such as protective eyeglasses and leather gloves.
• High-pressure oil leaking from small holes is dangerous
that may penetrate your skin and cause loss of sight if it
contacts your skin or eyes directly. If a jet of high-pressure
oil hit your skin or eyes, and suffer injury, wash the place
with clean water, and consult a doctor immediately for
medical attention.

Precautions for High-Pressure Fuel

While the engine is running, high-pressure is generated in the engine fuel piping. If you try to disassemble the
piping before the internal pressure is released, serious personal injury or death can result. When performing in-
spection or maintenance of the fuel piping system, stop the engine and wait for at least 30 seconds to allow the
internal pressure to go down before starting the work.

Handle High-Pressure Hoses and Piping

If oil or fuel leaks from high-pressure hoses or piping, it may cause fire or defective operation. It is dangerous
and may cause serious personal injury or death. If the hose or piping mounts are loose or oil or fuel is found to
be leaking from the mount, stop operations and tighten to the specified torque.
If any damaged or deformed hoses or piping are found, consult your Komatsu distributor.
Replace the hose if any of the following problems are found.
• Damaged hose or deformed hydraulic fitting.
• Frayed or cut covering or exposed reinforcement wire layer.
• Covering swollen in places.

2-33
Precautions for Maintenance Safety

• Twisted or crushed movable portion.

• Foreign material embedded in covering.

2-34
Safety Precautions for Maintenance

Precautions for High Voltage

When the engine is running and immediately after it is stopped,
high voltage is generated inside the engine controller and the
engine injector, and there is danger of electric shock. Never
touch the inside of the engine controller or the injector part of
the engine. If it is necessary to touch the inside of the engine
controller or the injector part of the engine, consult your Komat-
su distributor.

Precautions for Noise

When performing maintenance of the engine and you are exposed to noise for long periods of time, wear ear
covers or ear plugs while working.
If the noise is too loud, it may cause temporary or permanent hearing problems.

Precautions for High-Pressure Grease During Track Tension Adjustment

• Grease is pumped into the track tension adjustment sys-
tem under high pressure. If the specified procedure for
maintenance is not followed when making adjustment,
grease drain plug (1) may fly out and cause serious injury
or death or property damage.
• When loosening grease drain plug (1) to loosen the track
tension, never loosen it more than 1 turn. Loosen the
grease drain plug slowly.
• Never put your face, hands, feet, or any other part of your
body close to grease drain plug (1).

Do Not Disassemble Recoil Spring

Never disassemble the recoil spring assembly.
The recoil spring assembly has a powerful spring that acts to
reduce the impact on the idler. If it is disassembled by mistake,
the spring may shoot out and cause serious personal injury or
death. If it is necessary to disassemble it, ask your Komatsu
distributor to perform the work.

2-35
Precautions for Maintenance Safety

Handle Accumulator
This machine is equipped with an accumulator. Even after the engine stops, if the work equipment control lever
is operated after stop of the engine in the direction to lower the work equipment, the work equipment goes down
with its own weight.
After stopping the engine, set the parking brake lever and work equipment lock lever to LOCK positions.
The accumulator is charged with high-pressure nitrogen gas, so mistaken operation may cause an explosion,
which will lead to serious injury or death. Always observe the following.
• Do not disassemble it.
• Do not bring it near flame or dispose of it in fire.
• Do not make holes in it, weld it, nor use a cutting torch.
• Do not hit or roll it, or subject it to any impact.
• When disposing of the accumulator, the gas must be re-
leased. Ask your Komatsu distributor to perform this work.

Precautions for Compressed Air

• When performing cleaning with compressed air, there is a hazard of serious personal injury or death
caused by flying dust or particles.
• When using compressed air to clean the filter element or radiator, wear protective eyeglasses, anti-dust
mask, gloves, and other protective equipment.

Maintenance of Air Conditioner

If air conditioner refrigerant gets into your eyes, it may cause loss of sight; if it contacts your skin, it may cause
frostbite. Never loosen any parts of the cooling circuit.

Precautions When You Discard Waste Materials

To prevent pollution, pay full attention to the way to dispose of waste materials.
• Always drain the oil from your machine in containers. Nev-
er drain the oil and coolant directly onto the ground or
dump into the sewage system, rivers, seas, or lakes.
• Obey appropriate laws and regulations when disposing of
harmful objects such as oil, fuel, coolant, solvent, filters,
batteries, and DEF.

Avoid exposure to burning rubber or plastics which produce a toxic gas that is harmful to people.
• When disposing of parts made of rubber or plastics (hoses, cables, and harnesses), always comply with the
local regulations for disposing industrial waste products.

2-36
Safety Precautions for Maintenance

How to Select Window Washer Fluid

Use an ethyl alcohol base washer liquid.
Methyl alcohol base washer liquid may irritate your eyes, so do not use it.

Periodic Replacement of Defined Life Parts

• For using the machine safely for a long period, always perform periodic replacement of the defined life parts
that have a particularly close relation to safety, such as hoses and the seat belt.
Replacement of the defined life parts: See “Periodic Replacement of Defined Life Parts”.
• The material of these components naturally changes over time, and repeated use causes deterioration,
wear, and fatigue. As a result, there is a hazard that these components may fail and cause serious personal
injury or death. It is difficult to judge the remaining life of these components from external inspection or the
feeling when operating, so always replace them at the specified interval.
• Replace or repair the defined life parts if any defect is found, even when they have not reached the speci-
fied replacement time.

2-37
Precautions for DEF Safety

Precautions for DEF

General Character and Precautions for Handling
DEF is a colorless transparent 32.5% aqueous urea solution. Urea as main constituent is a material which is
used for cosmetics, medical and pharmaceutical products, and fertilizer, etc. The following situations require im-
mediate action:
• If it gets on your skin, it may cause inflammation. Immediately take the contaminated clothes or shoes off
and wash it off with water. In addition, use a soap to wash it off thoroughly. If your skin becomes irritated or
begins to hurt, immediately consult a doctor for treatment.
• Do not induce vomiting if swallowed. If swallowed, thoroughly rinse mouth with water and consult a doctor
for treatment.
• Avoid contact with the eyes. If there is contact, flush with clean water for several minutes and consult a doc-
tor for treatment.
• Wear protective eyeglasses when exposed to DEF to protect from solution splashing in your eyes. Wear
rubber gloves when you perform work handling DEF to avoid skin contact.

Precautions When You Add

Do not put fluid other than DEF into DEF tank. If diesel fuel or gasoline is added into the tank, it can cause a
fire. Some fluids or agents added can create and emit a toxic gas.
When opening the cap of DEF tank of the machine, the ammonia vapor may escape. Keep your face away from
the filler port during opening or refilling.

Precautions for Storage

If the temperature of DEF becomes high, a harmful ammonia gas may be emitted. Completely seal up its con-
tainer for storage. Only open containers in a well-ventilated area.
When storing DEF, avoid direct sunlight. Always use the original container it came in. Do not exchange the con-
tainer of DEF with another one. If DEF is stored in an iron or aluminum container, toxic gas may develop and a
chemical reaction may corrode the container.

Precautions for Fire Hazard and Leakage

DEF is non-flammable; however, in the case of a fire it may generate an ammonia gas.
If DEF is spilled, immediately wash and clean the area with water. If spilled DEF is left unattended and the area
is not washed and cleaned, it can cause corrosion to the contaminated area and emit toxic gas.

Other Precautions
When disposing of DEF, treat it as an industrial waste. The container for DEF is an industrial waste as well. It
should be treated in the same way.
Never use an iron or aluminum container when disposing DEF, because toxic gas may develop and a chemical
reaction may corrode the container. Use a container made of resin (PP, PE) or stainless steel when handling the
fluid waste of DEF.
Do not touch any fluid discharged from urea SCR. This fluid becomes acid by the influence of sulphur in the fuel
or built-in oxidation catalyzer. If it gets on your skin, thoroughly wash it off with water.
White powder (crystallized urea) may cover the exhaust pipe outlet of aftertreatment devices. When you wipe off
the covered materials, discard the crystallized urea and the used cloth as industrial waste.
Never relocate or modify the exhaust gas aftertreatment devices. The harmful gas may be exhausted and it can
cause serious damage to the environment as well as violation of laws.

2-38
 Operation

Please read and make sure that you understand the SAFETY section before
reading this section.

3-1
General View Operation

General View
Names of Machine Equipment

(1) Blade (7) Work equipment frame

(2) Front cover (8) Angle cylinder
(3) ROPS cab (9) Track frame
(4) Sprocket (10) Track
(5) Lift cylinder (11) Radiator grille
(6) Idler (12) Tilt cylinder

(13) DEF pump (15) Battery disconnect switch

(14) DEF tank (16) System operating lamp

3-2
Operation General View

(17) Komatsu Closed Crankcase Ventilation (hereafter (19) SCR

KCCV) ventilator
(18) DEF injector

Control Levers and Pedals

(1) Air conditioner switch (10) Starting switch

(2) Cigarette lighter (11) Decelerator/brake pedal
(3) Fuel control dial (12) Blade control lever
(4) Joystick (steering, directional and gear shift lever) (13) Horn switch
(5) Rear lamp switch (14) Room lamp switch
(6) Headlamp switch (15) Wiper switch
(7) Machine monitor (16) Parking brake lever
(8) Foot heater switch (17) Work equipment lock lever
(9) Engine shutdown secondary switch

3-3
General View Operation

Names of Machine Monitor Equipment

AA: Standard screen, BB: Check before starting screen, CC: Maintenance time warning screen
(1) Pedal mode selector switch (17) Steering mode display
(2) Buzzer cancel switch (18) Preheating pilot lamp
(3) Operating mode selector switch (19) Fan reverse rotation pilot lamp
(4) Reverse travel speed setting switch (20) FLOAT mode pilot lamp
(5) Gear shift mode selector switch (21) Blade mode display
(6) Service meter / clock (22) Multi-gauge
(7) Hydraulic oil temperature gauge (23) Fuel gauge
(8) ECO gauge or drawbar pull gauge (24) DEF level gauge
(9) Engine coolant temperature gauge (25) DEF level caution lamp
(10) Seat belt caution lamp (26) Fuel consumption gauge
(11) Engine stop pilot lamp (27) Engine oil pressure caution lamp
(12) Parking brake pilot lamp (28) Charge level caution lamp
(13) Work equipment lock pilot lamp (29) Speed range display
(14) Aftertreatment devices regeneration display (30) Function switches (F1 to F6)
(15) Message display (31) Maintenance time caution lamp
(16) Operating mode display
REMARK
The above figure does not show all of the caution lamp symbols.

3-4
Operation Explanation of Components

Explanation of Components
The following is an explanation of devices necessary to operate the machine.
To perform suitable operations correctly and safely, it is important to completely understand methods of operat-
ing the equipment, and the meanings of the displays.

Machine Monitor Equipment

AA: Standard screen, EE: Warning or Error screen, DD: Guidance screen
(1) Warning display (4) Speed range display
(2) Pilot display (5) Monitor switch area
(3) Meter display (6) Guidance icon display
REMARK
• If environmental temperature of the machine monitor is high, brightness may be automatically reduced to
protect the liquid crystal.
• Intensity or color of the objects may change because of the automatic adjustment function of the camera.

3-5
Explanation of Components Operation

Basic Operation of Machine Monitor

Basic Operation of Machine Monitor When You Start Engine in Normal Situation

• When the starting switch is turned to ON position, opening screen GG is displayed.

• After opening screen GG is displayed for 2 seconds, the screen switches to camera image FF.
• After camera image FF is displayed for 2 seconds, the screen switches to Check before starting screen BB.
• After Check before starting screen BB is displayed for 2 seconds, the screen switches to gear shift mode
display screen HH.
• After gear shift mode display screen HH is displayed for 2 seconds, the screen switches to standard screen
AA.
REMARK
When the engine is started, the battery voltage may suddenly drop depending on the temperature and the bat-
tery condition. If this happens, the machine monitor may restart, but this does not indicate any abnormality.

3-6
Operation Explanation of Components

Basic Operation of Machine Monitor When You Start Engine While Engine Shut-
down Secondary Switch is on
While engine shutdown secondary switch (1) is turned on (en-
gine is stopped), when the starting switch is turned to ON posi-
tion, the screen shown in the figure is displayed and engine
does not start.

If engine shutdown secondary switch (1) is turned off (normal),

the machine monitor switches to the standard screen, and you
can start the engine with usual starting switch key operation.

Basic Operation of Machine Monitor When You Stop Engine in Normal Situation

When the starting switch is turned to OFF position, end screen JJ or KK is displayed for 5 seconds, then the
display goes out.
End Screen When a Message is Received
If there is any message from your Komatsu distributor, it is dis-
played on the end screen.
In this case, turn the starting switch to ON position to re-check
the message, and if the message is requesting a response,
make a reply to it.

3-7
Explanation of Components Operation

Basic Operation of Machine Monitor When Starting Switch is ON While Operator

ID Input is Set

• If inputting ID number for operator identification function (with SKIP) is set, the opening screen GG switches
to ID number input screen LL (with SKIP) when the starting switch is turned to ON position.
• If inputting ID number for operator identification function (without SKIP) is set, the opening screen GG
switches to ID number input screen MM (without SKIP) when the starting switch is turned to ON position.
• On the ID number input screen LL (with SKIP) or MM
(without SKIP), input the already registered ID number,
and press switch F6. The screen changes to the Check
Before Starting screen BB. If you input an incorrect ID
number, press switch F5, and clear an input character at a
time.

On the ID number input screen LL (with SKIP), press

switch F1, and the screen changes to the Check Before
Starting screen BB without inputting ID number.
REMARK
• Contact your Komatsu distributor for details of the method
of setting, changing, or canceling the operator identifica-
tion function.
• Depending on the set value of ID holding time, even if in-
putting ID number for operator identification function is set,
the ID number input screen LL (with SKIP) or MM (without
SKIP) may not be displayed while the starting switch is
turned to ON position.
If inputting incorrect ID number for 3 times continuously, you cannot input ID number for 5 minutes. Wait for
more than 5 minutes, try inputting ID number again.
As long as ID number input screen is displayed, the engine cannot be started. If you forget the ID number and
cannot start the engine, confirm the person in charge of the machine.

3-8
Operation Explanation of Components

NOTICE
Since the purpose of the operator identification function is neither security enhancement nor a protec-
tion against theft, it has no antitheft effect. Be careful not to use it for the purpose of security enhance-
ment.
Komatsu cannot accept any responsibility for any loss or damage resulting from the wrong use of ID or
unauthorized use of ID by a third person.

Basic Operation of Machine Monitor When You Start Engine in Abnormal Situa-
tion

• If there is any abnormality when starting the engine, the check before starting screen BB changes to the
maintenance time warning screen CC, warning screen FF-1, or error screen EE.
• After displaying the checks before starting screen BB for 2 seconds, the screen changes to the mainte-
nance time warning screen CC.
• After displaying the maintenance time warning screen CC for 30 seconds, the screen returns to the stand-
ard screen AA.
• After displaying the check before starting screen BB for 2 seconds, the screen changes to the warning
screen FF-1 or error screen EE.
• After displaying warning screen FF-1 for 2 seconds, the screen changes to warning screen FF-2.

3-9
Explanation of Components Operation

If there is any abnormality currently generated, “!” is displayed

on top of switch F5.

Press switch F5 to check the detail of the current abnormality.

The “Current Abnormality” screen is displayed.

3-10
Operation Explanation of Components

Basic Operation of Machine Monitor When Trouble Occurs While You Operate
Machine

If any abnormality occurs during operation, the standard screen AA changes to the abnormality screen EE.
If there is any error existing, “!” is displayed on top of switch F5.

Press switch F5 to check the detail of the current abnormality.

The “Current Abnormality” screen is displayed.

3-11
Explanation of Components Operation

Warning Display
NOTICE
Appearance of any of action levels “L01” to “L04” on the machine monitor indicates presence of an ab-
normality of the machine.
Take appropriate actions following the list of action level displays and required actions.
The caution lamp that lights up in red when an action level is displayed warns operator to stop the ma-
chine urgently, stop or pause the current operation.
If no action is taken, the machine can be seriously affected. Take necessary actions immediately.

(1) Action level display (6) Engine speed caution lamp (*)
(2) Caution lamp (7) DEF level caution lamp
(3) Caution lamp (8) Fuel level caution lamp
(4) Hydraulic oil temperature caution lamp (9) Caution lamp
(5) Engine coolant temperature caution lamp
(*): Displayed items change according to setting of the multi-gauge. For details of the multi-gauge, see “Multi
Gauge”.
Standard screen
When 1 type of caution is generated, it is displayed on caution lamp (2).
When 2 types of cautions are generated, they are displayed on caution lamps (2) and (3).
When 3 types or more of caution are generated, they are displayed on caution lamps (2) and (3) alternately at
intervals of 2 seconds.
Camera image display screen
The current cautions are indicated by flashing of caution lamp (9).
When 2 or more cautions are generated, they are sequentially displayed starting from the leftmost side of the
screen.

3-12
Operation Explanation of Components

Action Level Display

Action level display indicates the degree of urgency of the ab-
normality currently generated on the machine by “L01” to “L04”.
The larger the number in the table is, the more serious effects
the abnormality may have on the machine if it is left with no ac-
tion.
If the machine monitor indicates an action level, check the
message of the action level display.
By pressing switch F5 on the standard screen while the action
level is displayed, the list of the Current Abnormality is dis-
played.
When the machine monitor displays an action level, take ap-
propriate actions according to “List of action level displays and
required actions”.

List of Procedure Level Display and Required Procedures

Degree
Action lev-
of ur- Buzzer Caution lamp Required action
el
gency
Sounds contin- Lights up in Stop the machine immediately and ask your Komatsu distrib-
L04
uously red utor for inspection and maintenance.
High Stop the operation and move the machine to a safe place,
Sounds inter- Lights up in
↑ L03 then ask your Komatsu distributor for inspection and mainte-
mittently red
nance.
│
│ Stop the operation and run the engine at medium speed with
Sounds inter- Lights up in no load or stop it.
│ L02
mittently red If the condition is not improved, ask your Komatsu distributor
│
for inspection and maintenance.
│
Some functions may be restricted from use, but the machine
↓ can operate. When you finish the operation, always perform
Low Does not Lights up in the inspection and maintenance.
L01
sound yellow
Ask your Komatsu distributor for inspection and maintenance
as needed.

3-13
Explanation of Components Operation

Caution Lamp List

NOTICE
• These caution lamps do not guarantee the condition of the machine.
Do not simply rely on the caution lamp when performing checks before starting (start-up inspec-
tion). Always get off the machine and check each item directly.
• When the caution lamp is displayed in red, if no action is taken, the machine can be seriously affec-
ted.
Take the action immediately.
• The engine output or engine speed is limited and the machine operation speed may become slow,
depending on the contents of the warning.
• When the engine output or engine speed is limited by the warning of action level “L03” or higher,
the limit may not be canceled even if the warning is canceled.
In this case, stop the machine and lower the engine speed to low idle with the fuel control dial or the
decelerator/brake pedal. The engine output or engine speed limitation is reset.

Caution Lamps and Display Colors

Display color/ Machine condition (Action level)
Symbol Type of caution lamp
Red Yellow Blue White

High temper-
Engine coolant temperature cau- ature - Normal -
tion lamp
(L02)

High temper-
Hydraulic oil temperature caution ature - Normal -
lamp
(L02)

Fuel level caution lamp Low level - Normal -

Abnormal Abnormal
System caution lamp - -
(L04, L03) (L01)

Work equipment system caution Abnormal Abnormal

- -
lamp (L03) (L01)

Abnormal Abnormal
Steering system caution lamp - -
(L04, L03) (L01)

Abnormal Abnormal
Brake system caution lamp - -
(L03) (L01)

Abnormal Abnormal
HST system caution lamp - -
(L04, L03) (L01)

Aftertreatment devices system Abnormal Abnormal

- -
caution lamp (L04, L03) (L01)

3-14
Operation Explanation of Components

Display color/ Machine condition (Action level)

Symbol Type of caution lamp
Red Yellow Blue White

Regeneration performance caution Abnormal Abnormal

- -
lamp (L03) (L01)

Abnormal Sensing is
DEF level caution lamp - Normal
(L04, L03) disabled

Abnormal Abnormal
DEF system caution lamp - -
(L04, L03) (L01)

Engine stop-
DEF system high temperature stop ped at high
- temperature - -
caution lamp
(L01)

Abnormal Abnormal
Engine system caution lamp - -
(L04, L03) (L01)

Parking brake system caution Abnormal Abnormal

- -
lamp (L04, L03) (L01)

Abnormal Abnormal
Fan control system caution lamp - -
(L04, L03) (L01)

Low oil pres-

Engine oil pressure caution lamp sure - - -
(L03)

Overspeed
Engine overrun caution lamp - - -
(L02)

Abnormal
Charge level caution lamp - - -
(L03)

Abnormal
HST oil filter clogging caution lamp - - -
(L02)

Abnormal
HST oil pressure caution lamp - - -
(L02)

Water separator caution lamp Abnormal - - -

3-15
Explanation of Components Operation

Display color/ Machine condition (Action level)

Symbol Type of caution lamp
Red Yellow Blue White

Clogged
Air cleaner clogging caution lamp - - -
(L01)

Due time is
Maintenance time caution lamp Notice - -
over

Seat belt is
Seat belt caution lamp - - -
not fastened

For the meaning of each caution lamp and the action to take for it, see the section of each caution lamp.

3-16
Operation Explanation of Components

Current Abnormality Display Switch

If there is any abnormality currently generated, “!” is displayed
on top of switch F5.
While “!” is displayed, press switch F5 to shift the monitor dis-
play screen to the “Current Abnormality” screen.
Take appropriate actions according to the displayed message.

Operation on “Current Abnormality” Screen

On the “Current Abnormality” screen, you can perform the fol-
lowing operations with switches F1, F2 and F5.

F1: Displays the next page. When on the last page, it displays
the first page.
F2: Displays the previous page. When on the first page, it dis-
plays the last page.

F5: Returns the screen to the standard screen.

3-17
Explanation of Components Operation

Engine Coolant Temperature Caution Lamp

Engine coolant temperature caution lamp warns about states
caused by engine coolant temperature.
When abnormal
The caution lamp lights up in red and indicates action level
“L02”.
The engine coolant temperature is abnormally high.
While this lamp is lit, the overheat prevention system is auto-
matically actuated and the engine speed drops.
Stop operations and run the engine at low idle until the caution
lamp changes to the normal display color (blue) at a proper
temperature.
When temperature is proper
The caution lamp lights up in blue.

Hydraulic Oil Temperature Caution Lamp

The hydraulic oil temperature caution lamp warns about states
of hydraulic oil temperature.
When abnormal
The caution lamp lights up in red and indicates action level
“L02”.
The hydraulic oil temperature is abnormally high.
Stop operations and stop the engine or run it at low idle until
the caution lamp changes to the normal display color (blue) at
an appropriate temperature.
When temperature is proper
The caution lamp lights up in blue.

Fuel Level Caution Lamp

The fuel level caution lamp warns about low level of remaining
fuel.
When fuel level is low
The caution lamp lights up in red.
The remaining fuel amount is approximately 39 ℓ
{10.3 U.S.Gal} or less.
Add fuel as soon as possible.
When normal
The caution lamp lights up in blue.
REMARK
• It does not indicate correct fuel level on the slopes. Place the machine on a level ground and check the fuel
level.
• Check the fuel level on a level ground before operating on the slopes.
• When operating the machine on the slopes for a long time, move the machine to a level ground to check
the fuel level, and continue the operation.

3-18
Operation Explanation of Components

System Caution Lamp

The system caution lamp warns about abnormality in the ma-
chine system, including the sensors.
When action level “L04” is displayed
The caution lamp lights up in red and the alarm buzzer sounds
continuously.
Stop the machine immediately and ask your Komatsu distribu-
tor for inspection and maintenance.
When action level “L03” is displayed
The caution lamp lights up in red and the alarm buzzer sounds
intermittently.
Stop the operation and move the machine to a safe place, then ask your Komatsu distributor for inspection and
maintenance.
When action level “L01” is displayed
The caution lamp lights up in yellow.
Some functions may be restricted for use, but the machine can operate.
When you finish the operation, always perform the inspection and maintenance.
Ask your Komatsu distributor for inspection and maintenance as needed.

Work Equipment System Caution Lamp

The work equipment system caution lamp warns about abnor-
mality in the work equipment system.
When action level “L03” is displayed
The caution lamp lights up in red and the alarm buzzer sounds
intermittently.
Stop the operation, move the machine to a safe place, and
then ask your Komatsu distributor for the inspection and main-
tenance.
When action level “L01” is displayed
The caution lamp lights up in yellow.
Some functions may be restricted from use, but the machine can operate.
When you finish the operation, always perform the inspection and maintenance.
Ask your Komatsu distributor for the inspection and maintenance as needed.

Steering System Caution Lamp

The steering system caution lamp warns about abnormality in
the steering system.
When action level “L04” is displayed
The caution lamp lights up in red and the alarm buzzer sounds
continuously.
Stop the machine immediately and ask your Komatsu distribu-
tor for inspection and maintenance.
When action level “L03” is displayed
The caution lamp lights up in red and the alarm buzzer sounds
intermittently.
Stop the operation, move the machine to a safe place, and then ask your Komatsu distributor for the inspection
and maintenance.

3-19
Explanation of Components Operation

When action level “L01” is displayed

The caution lamp lights up in yellow.
Some functions may be restricted for use, but the machine can operate.
When you finish the operation, always have the inspection and maintenance performed.
As needed, ask your Komatsu distributor for inspection and maintenance.

Brake System Caution Lamp

The brake system caution lamp warns about abnormality in the
brake system.
When action level “L03” is displayed
The caution lamp lights up in red and the buzzer sounds inter-
mittently.
Stop the operation, move the machine to a safe place, and
then ask your Komatsu distributor for the inspection and main-
tenance.
When action level “L01” is displayed
The caution lamp lights up in yellow.
Some functions may be restricted from use, but the machine can operate.
When you finish the operation, always perform the inspection and maintenance.
Ask your Komatsu distributor for the inspection and maintenance as needed.

HST System Caution Lamp

HST system caution lamp warns about abnormality in the HST
system.
When action level “L04” is displayed
The caution lamp lights up in red and the alarm buzzer sounds
continuously.
Stop the machine immediately and ask your Komatsu distribu-
tor for inspection and maintenance.
When action level “L03” is displayed
The caution lamp lights up in red and the alarm buzzer sounds
intermittently.
Stop the operation, move the machine to a safe place, and then ask your Komatsu distributor for the inspection
and maintenance.
When action level “L01” is displayed
The caution lamp lights up in yellow.
Some functions may be restricted from use, but the machine can operate.
When you finish the operation, always perform the inspection and maintenance.
Ask your Komatsu distributor for the inspection and maintenance as needed.

3-20
Operation Explanation of Components

HST Oil Pressure Caution Lamp

HST caution lamp warns about abnormality of HST oil pres-
sure.
When oil pressure is low
The caution lamp lights up in red, and action level “L02” is dis-
played.
The alarm buzzer sounds intermittently.
Stop operations, and run the engine at low idle or stop the en-
gine until the caution lamp goes out.
If the caution lamp does not go out, ask your Komatsu distribu-
tor for inspection and maintenance.

HST Oil Filter Clogging Caution Lamp

HST oil filter clogging caution lamp warns about clogging of the
HST oil filter.
When clogged
The caution lamp lights up in red, and action level “L02” is dis-
played.
The alarm buzzer sounds intermittently.
HST filter is clogged.
Stop the engine, and replace the HST oil filter cartridge with a
new one.
For replacement of the filter element, see “Change Oil in Hy-
draulic Tank, Replace Hydraulic Oil Filter Cartridge, Replace HST Oil Filter Cartridge, and Clean Hydraulic Tank
Strainer”.
If the caution lamp does not go out, ask your Komatsu distributor for inspection and maintenance.

Aftertreatment Device System Caution Lamp

This warns about defects of the aftertreatment devices system.
When action level “L04” appears on screen.
The caution lamp comes on in red and the alarm buzzer oper-
ates continuously.
Stop the machine immediately and ask your Komatsu distribu-
tor for inspection and maintenance.
When action level “L03” appears on screen.
The caution lamp comes on in red and the alarm buzzer oper-
ates intermittently.
Stop the work and move the machine to a safe area. Ask your Komatsu distributor for inspection and mainte-
nance.
When action level “L01” appears on screen.
The caution lamp comes on in yellow.
It is not necessary to stop the machine immediately.
However, it is recommended to inspect the machine for maintenance after you finish operations.
Ask your Komatsu distributor for inspection and maintenance as necessary.

3-21
Explanation of Components Operation

Regeneration Performance Caution Lamp

This warns about the deterioration of regeneration performance
of aftertreatment devices.
When action level “L03” appears on screen.
The caution lamp comes on in red and the alarm buzzer oper-
ates continuously.
Move the machine to a safe area and activate manual station-
ary regeneration.
When action level “L01” appears on screen.
The caution lamp comes on in yellow.
Move the machine to a safe area and activate manual stationary regeneration after the end of work.

DEF Level Caution Lamp

DEF level caution lamp alerts when DEF tank level becomes
low.
Whenever the caution lamp lights up in red, immediately add
DEF.
Fault conditions that result in activation of the Inducement strat-
egy for engine derates to prompt to maintain or repair the emis-
sion control system.
When Lightning in red,
With Action level “L04”, DEF tank level is too low. Inducement
status is “Final Inducement”. Engine speed is fixed at low idle.
With Action level “L04”, DEF tank level is too low. Inducement status is “Severe Inducement”. Engine power is
under heavy deration.
With Action level “L03”, DEF tank level is low. Inducement status is “Mild Inducement”. Engine power is under
deration.
With No Action level display. DEF tank level is lower. Inducement status is “Escalated Warning”. Need to add
DEF immediately to avoid advancing to the next Inducement status.
With No Action level display. Warning starts. Inducement status is “Warning”. Need to add DEF immediately.
When Lightning in white
When fluctuation of DEF tank level is large, frozen, or not limited to, tank level sensing is not performed correct-
ly.
When DEF is added after engine starting switch turn to OFF.
When DEF tank level sensor is defective.

DEF System Caution Lamp

DEF system caution lamp alerts when abnormality in the sys-
tem are detected.
Whenever the caution lamp lights up in yellow or in red, take
necessary actions by instructions.
Fault conditions that result in activation of the Inducement strat-
egy for engine derates to prompt to maintain or repair the emis-
sion control system.
Lighting in red
With Action level “L04”, Inducement status is “Final Induce-
ment”. Engine speed is fixed at low idle.
With Action level “L04”, Inducement status is “Severe Inducement”. Engine power is under heavy deration.
With Action level “L03”, Inducement status is “Mild Inducement”. Engine power is under deration.

3-22
Operation Explanation of Components

Lighting in yellow
With Action level “L01”, Inducement status is “ Warning” or “Escalated Warning”.
When “Escalated Warning”, If no maintenance, advancing to the next Inducement status. Engine power will be
derated.

DEF System High Temperature Stop Caution Lamp

DEF system high temperature stop caution lamp alerts when
the times of engine is shut down under the condition of high de-
gree temperature of DEF system exceeds the defined number
of times.
Whenever the caution lamp lights up in yellow, it is necessary
to ask your Komatsu distributor to go off this caution lamp.

Parking Brake System Caution Lamp

The parking brake system caution lamp warns about abnormal-
ity in the parking brake system.
When action level “L04” is displayed
The caution lamp lights up in red and the alarm buzzer sounds
continuously.
Stop the machine immediately and ask your Komatsu distribu-
tor for inspection and maintenance.
When action level “L03” is displayed
The caution lamp lights up in red and the alarm buzzer sounds
intermittently.
Stop the work, move the machine to a safe place, and then ask your Komatsu distributor for inspection and
maintenance.
When action level “L01” is displayed
The caution lamp lights up in yellow.
Some functions may be restricted for use, but the machine can operate.
When you finish the operation, always perform the inspection and maintenance.
Ask your Komatsu distributor for inspection and maintenance as needed.

Engine System Caution Lamp

The engine system caution lamp warns about defect in the en-
gine system.
When action level “L04” appears on screen
The caution lamp comes on in red and the alarm buzzer oper-
ates continuously.
Stop the machine immediately and ask your Komatsu distribu-
tor for inspection and maintenance.
When action level “L03” appears on screen.
The caution lamp comes on in red and the alarm buzzer oper-
ates intermittently.
Move the machine to a safe area and stop the machine, then ask your Komatsu distributor for inspection and
maintenance.

3-23
Explanation of Components Operation

When action level “L01” appears on screen.

The caution lamp comes on in yellow.
It is not necessary to stop the machine immediately.
However, it is recommended for maintenance after the end of ongoing work.
Ask your Komatsu distributor for inspection and maintenance as necessary.

Fan Control System Caution Lamp

The fan control system caution lamp warns about abnormality
in the fan control system.
When action level “L04” is displayed
The caution lamp lights up in red and the alarm buzzer sounds
continuously.
Stop the machine immediately and ask your Komatsu distribu-
tor for inspection and maintenance.
When action level “L03” is displayed
The caution lamp lights up in red and the alarm buzzer sounds
intermittently.
Stop the work, move the machine to a safe place, and then ask your Komatsu distributor for inspection and
maintenance.
When action level “L01” is displayed
The caution lamp lights up in yellow.
Some functions may be restricted for use, but the machine can operate.
When you finish the operation, always have the inspection and maintenance performed.
Ask your Komatsu distributor for inspection and maintenance as needed.

Engine Oil Pressure Caution Lamp

Engine oil pressure caution lamp warns about abnormality of
engine lubricating oil pressure.
When oil pressure is low
The caution lamp lights up in red and indicates action level
“L03”.
The alarm buzzer sounds intermittently.
Stop the operation and move the machine to a safe place, then
ask your Komatsu distributor for inspection and maintenance.

Engine Overrun Caution Lamp

The engine overrun caution lamp warns about the overspeed of
engine.
When engine overspeeds
The caution lamp lights up in red, and action level “L02” is dis-
played.
The alarm buzzer sounds intermittently.
Since overspeed can damage the engine and hydraulic compo-
nents, stop the work immediately and operate the machine at
low travel speed until the engine overrun caution lamp goes
out.

3-24
Operation Explanation of Components

Charge Level Caution Lamp

Charge level caution lamp warns about abnormality in the
charging system while the engine is running.
When abnormal
The caution lamp lights up in red, and action level “L03” is dis-
played.
The alarm buzzer sounds intermittently.
Charging is not performed normally while the engine is running.
Stop the engine and check the alternator drive belt for damage,
and then ask your Komatsu distributor for inspection and main-
tenance.

Water Separator Caution Lamp

The water separator caution lamp warns that water is accumu-
lated in the water separator.
When abnormal
The caution lamp lights up in red.
Water is accumulated in the water separator.
Stop the engine and drain water from the water separator.
For detail, see “METHOD FOR CHECKING WATER SEPARA-
TOR, DRAINING WATER AND SEDIMENT”.
REMARK
The water separator forms one unit with the fuel prefilter.
The water separator is installed at the bottom of the fuel prefil-
ter as detachable condition.

Air Cleaner Clogging Caution Lamp

Air cleaner clogging caution lamp warns about clogging of the
air cleaner.
When clogged
The caution lamp lights up in yellow and indicates action level
“L01”.
The air cleaner is clogged.
Stop the engine and check and clean the air cleaner.
For detail, see “How to Examine, Clean and Replace Air Clean-
er”.

3-25
Explanation of Components Operation

Maintenance Time Caution Lamp

Maintenance time caution lamp displays notices and alarms
concerning maintenance time.
This lamp lights up when the starting switch is turned to ON po-
sition. It goes out after 30 seconds and the display changes to
the standard screen.
When the due time is over
The caution lamp lights up in red.
The maintenance due time is over.
If no action is taken, the machine performance will become
worse and the machine life will be shortened.
Perform necessary maintenance as soon as possible.
When giving the notice of the due time
The caution lamp lights up in yellow.
The maintenance due time is approaching.
Prepare necessary parts for the maintenance.
REMARK
• Check maintenance items on the “Maintenance” screen by
pressing switch F6 on the maintenance time warning
screen shown in the drawing or on the standard screen.
• The lighting time of maintenance due time notice (yellow)
has been initially set to 30 hours, but it can be changed.
To change the setting, ask your Komatsu distributor.
• For operations on the “Maintenance” screen, see “Mainte-
nance Screen Setting”.

Seatbelt Caution Lamp

The seat belt caution lamp lights up in red when the seat belt is
not fastened. It goes out when the seat belt is fastened.
For fastening the seat belt, see “How to Fasten and Unfasten
Seat Belt”.

3-26
Operation Explanation of Components

Pilot Display and Meter Display

Pilot display
(1) Engine stop pilot lamp (8) Preheating pilot lamp
(2) Parking brake pilot lamp (9) Fan reverse pilot lamp
(3) Work equipment lock pilot lamp (10) FLOAT mode pilot lamp
(4) Aftertreatment devices regeneration display (11) Blade mode display
(5) Message display (12) Guidance display
(6) Operating mode display (13) Speed range display
(7) Steering mode display
Meter display
(14) Service meter / clock (18) Multi-gauge
(15) Hydraulic oil temperature gauge (19) Fuel gauge
(16) ECO gauge or drawbar pull gauge (20) DEF level gauge
(17) Engine coolant temperature gauge (21) Fuel consumption gauge

Pilot Display
The pilot display at the top of the screen consists of the pilot lamps to check the actuation of each function.
When the starting switch is turned on and the display items are functioning, the pilot lamps light up.

Preheating Pilot Lamp

The preheating pilot lamp is displayed while the engine is pre-
heated before starting at temperature below 0 °C {32.0 °F} .
When the temperature is low (in cold weather) and the auto-
matic preheating function operates, the preheating pilot lamp
lights up. When the preheating is completed, it goes out.
Automatic preheating is for a maximum of approximately 30
seconds.

3-27
Explanation of Components Operation

Fan Reverse Rotation Pilot Lamp

The fan reverse rotation pilot lamp lights up while the fan is ro-
tating in reverse.
For canceling the fan reverse rotation, turn the starting switch
to OFF position and wait for 15 seconds or more, and turn the
starting switch to ON position.

Message Display
The User Message is displayed when there is a message from
Komatsu.
To read the message, see “Message Display”.
Lights up in green (A): There is unread message.
Lights up in blue (B): There is any read message to which no
reply has been made.
OFF: No messages

Operating Mode Display

The currently set operating mode is displayed on the operating
mode display.
The display of the operating mode is as follows.
(P): For heavy-duty operations
Lights up when the mode is set to power mode.
(E): For operations with emphasis on fuel consumption
Lights up when the mode is set to economy mode.
The operating mode changes each time the operating mode
selector switch is pressed.

Engine Stop Pilot Lamp

The engine stop pilot lamp is displayed while the engine is
stopped. It goes out when the engine is started.

3-28
Operation Explanation of Components

Aftertreatment Device Regeneration Display

This displays the regeneration status and automatic regenera-
tion setting status of the aftertreatment devices.
(A): Comes on during regeneration.
(B): Comes on when setting automatic regeneration disable.

Work Equipment Lock Pilot Lamp

The work equipment lock pilot lamp lights up when the work
equipment lock lever is in LOCK position.
It goes out when the work equipment lock lever is set in FREE
position.
If it is required to set the work equipment lock lever in LOCK
position, the work equipment lock pilot lamp flashes.

Parking Brake Pilot Lamp

The parking brake pilot lamp lights up when the parking brake
lever is in LOCK position.
It goes out when the parking brake lever is set to FREE posi-
tion.
When the parking brake lever needs to be set to LOCK posi-
tion, the parking brake pilot lamp flashes.

Float Mode Pilot Lamp

The float mode pilot lamp lights up when the machine is in the
float mode.
How to set FLOAT mode
Operate the blade control lever to LOWER stroke end while
pressing FLOAT button on top of the blade control lever.
How to cancel FLOAT mode
Operate the blade control lever from HOLD position to RAISE
or LOWER position.
REMARK
When FLOAT mode is set or canceled, electronic sound of
beep is heard.

3-29
Explanation of Components Operation

Blade Mode Display

The currently set blade mode is displayed on the blade mode
display.
The display of the blade mode is as follows.
(A): For fast operation
Lights up when it is set to FAST mode.
(B): For general operation
Lights up when it is set to NORMAL mode.
(C): For last leveling operation
Lights up when it is set to FINE mode.
Press customize switch to set the blade mode.
For details of the setting method, see “Customize Switch”.

Steering Mode Display

The currently set steering mode is displayed on the steering
mode display.
The display of the steering mode is as follows.
(A): Lights up when the mode is set to NORMAL mode.
(B): Lights up when the mode is set to FINE mode.
Steering mode is set by depressing the customize switch.
For details of the setting method, see“Customize Switch”.

3-30
Operation Explanation of Components

Guidance Display
The guidance for energy saving operation to reduce the fuel
consumption may be displayed during operation.
The details of the guidance are as follows:

Idling Stop Guidance

If no operation is performed for more than 5 minutes, and the
engine is idling, the idling stop message is displayed on the
machine monitor. When waiting for work or taking short break,
stop the engine to reduce unnecessary fuel consumption.
The idling stop guidance goes out if any lever is operated again
or switch F5 is pressed.

Guidance to Avoid Hydraulic Relief

If the hydraulic oil is kept relieved for more than 10 seconds
during operation, the hydraulic relief deterrence message is
displayed on the machine monitor.
The hydraulic relief deterrence message goes out 5 seconds
later or when switch F5 is pressed.

E Mode Recommendation Guidance

If light-load work is continued for more than 10 minutes in P
mode, E mode recommendation message is displayed on the
machine monitor. When working on light load, set the operating
mode to E to reduce unnecessary fuel consumption.
E mode recommendation guidance goes out more than 5 sec-
onds after or when switch F5 is pressed.

3-31
Explanation of Components Operation

Overload Prevention Guidance

If the machine is overloaded during work, overload prevention
message is displayed on the machine monitor.
Fuel consumption can be reduced by avoiding shoe slip or op-
erating the machine in the green zone of ECO gauge.
Overload prevention guidance goes out more than 5 seconds
later or when switch F5 is pressed.

DEF Low Level Guidance

At 15 seconds after the starting switch is turned to ON position and the standard screen is displayed, if the oper-
able time estimated from current DEF level and the latest average DEF consumption is shorter than 8 hours,
DEF low level message is displayed.
When the time until engine power deration starts is 1 to 8 hours
“Approx. * hours remaining to DEF refill caution.” is displayed.

When the time until engine power deration starts is less than 1 hour
“DEF refill caution will appear soon.” is displayed.

DEF low level guidance goes out in more than 15 seconds or when switch F5 is pressed.
Add DEF to the DEF tank before engine power is to be derated.
Guidance of Engine Stop Operation During Aftertreatment Device Regeneration
Immediately after starting aftertreatment devices regeneration,
the information about engine stop operation during the after-
treatment devices regeneration is displayed on the machine
monitor.
The guidance for engine stop operation during regeneration of
the aftertreatment devices goes out 10 seconds later or when
switch F5 is pressed.

3-32
Operation Explanation of Components

Speed Range Display

The speed range display section indicates the following infor-
mation.
Bar graph (A): Lights up in accordance with the set speed in
forward.
Bar graph (B): Lights up in accordance with the set speed in re-
verse.
(C): The travel speed range of the machine (“F1” for FOR-
WARD 1st, “R2” for REVERSE 2nd) is displayed.
In variable shift mode, the speed range is not displayed.
(D): The gear shift mode is displayed.
(E): Pedal mode is displayed.
In gear shift mode, quick shift mode and variable shift mode
are available.
(F): Quick shift mode
(G): Variable shift mode

In pedal mode, decelerator mode and brake mode are availa-

ble.
(H): Decelerator mode
(I): Brake mode

3-33
Explanation of Components Operation

Meter Display
Multi Gauge
The multi gauge can display various items. As an example, dis-
play of the engine tachometer is explained below.
If the indicator is in green range during operations, it is normal.
When the indicator goes beyond (A) of red range during opera-
tions, the engine speed is too high. Decrease the travel speed
in this case.
(A) to (B): Red range
(A) to (C): Green range
For other items displayed by the multi gauge, see “Use Multi
Gauge”.

Engine Coolant Temperature Gauge

Engine coolant temperature gauge shows the engine coolant
temperature.
If the indicator is in green range during operations, it is normal.
If the indicator goes beyond (A) of red range during operations,
the overheat prevention system operates.
(A) to (B): Red range
(A) to (C): Green range
(C) to (D): White range
The overheat prevention system is actuated as follows.
Red range (A) position: Engine coolant temperature caution lamp (E) shows abnormality display.
Red range (B) position: Engine speed changes to a medium speed, engine coolant temperature caution lamp
(E) shows abnormality display, and alarm buzzer sounds at the same time.
The overheat prevention system continues to operate until the indicator enters the green range.
When the engine is started, if the indicator is within white range (D), perform the warm-up operation.
Display (H) when temperature is correct: Back ground (K) of
engine coolant temperature caution lamp lights up in blue.
Display (J) when temperature is abnormal: Back ground (K) of
engine coolant temperature caution lamp lights up in red.

3-34
Operation Explanation of Components

Hydraulic Oil Temperature Gauge

Hydraulic oil temperature gauge shows the hydraulic oil tem-
perature.
If the indicator is in green range during operations, it is normal.
If the indicator goes beyond red range (A) during operations,
the overheat prevention system operates.
(A) to (B): Red range
(A) to (C): Green range
(C) to (D): White range
The overheat prevention system is actuated as follows.
Red range (A) position: Hydraulic oil temperature caution lamp (E) shows abnormality display.
Red range (B) position: Engine speed changes to a middle level, hydraulic oil temperature caution lamp (E)
shows abnormality display, and alarm buzzer sounds at the same time.
The overheat prevention system continues to operate until the indicator enters the green range.
When the engine is started, if the indicator is within white range (C) to (D), perform the warm-up operation.
NOTICE
When the indicator comes close to red range (A) during operation, run the engine at low idle or stop it,
and wait for the hydraulic oil temperature to drop.
Display (H) when temperature is correct: Background (K) of hy-
draulic oil temperature caution lamp lights up in blue.
Display (J) when abnormal: Background (K) of hydraulic oil
temperature caution lamp lights up in red.

Fuel Gauge
Fuel gauge shows the amount of fuel in the fuel tank.
The indicator should be in the green range during operations.
When the indicator comes close to red range (A) during opera-
tion, check and add fuel.
(A) to (B): Red range
(A) to (C): Green range

3-35
Explanation of Components Operation

REMARK
• When the indicator is in red ranges (A) to (B), fuel level caution lamp (D) lights up in red.
• The correct fuel level may not be displayed for a short time after the starting switch is turned to ON position,
but this is not abnormal.
• It does not indicate correct fuel level on the slopes. Place the machine on a level ground and check the fuel
level.
• Check the fuel level on a level ground before operating on the slopes.
• When operating the machine on the slopes for a long time, move the machine to a level ground to check
the fuel level, and continue the operation.

3-36
Operation Explanation of Components

Service Meter/Clock
The service meter / clock shows the total hours of operation of
the machine or the present time.
When the engine is running, the service meter advances even
when the machine is not moving. The service meter advances
0.1 every 6 operation minutes, regardless of the engine speed.
By pressing switch F4 on the standard screen, you can switch
the clock display and service meter display.
REMARK
• If the battery is disconnected for a long period for storage
etc., the time information may be lost.
• 12-hour or 24-hour system is available for clock display.
• For details of setting and correction of time, see “Clock Ad-
justment”.
Service meter display

Clock display (12-hour display)

Clock display (24-hour display)

3-37
Explanation of Components Operation

ECO Gauge/Drawbar Pull Gauge

The ECO gauge/ drawbar pull gauge displays ECO gauge (in-
stantaneous fuel consumption) (C) or drawbar pull gauge (work
load) (D).
The instantaneous fuel consumption means the fuel consump-
tion rate at each moment, which varies with the work load and
engine speed.
When the gauge is in green range (A), the instantaneous fuel
consumption is at a good to medium level.
When the gauge is in yellow range (B), the instantaneous fuel
consumption is at a bad level.
REMARK
Although there is no abnormality on the machine when the gauge enters the yellow range, for the conservation
of global environment reduce the engine output to a point where there is no adverse effect on the operation.
Perform energy saving operations within the green range. Travel less frequently. It also helps energy saving op-
erations. Consider the best way of operation for energy saving.

Fuel Consumption Gauge

Fuel consumption gauge shows the average fuel consumption
of the machine.
(A): Shows the average fuel consumption of a day (from 0:00
a.m. of the day to 0:00 a.m. of the next day).
(B): Shows the split fuel consumption under measurement.
(C): Shows the split fuel consumption while measurement is
stopped.
REMARK
Display on the fuel consumption gauge can be switched be-
tween the average fuel consumption per day and the average
fuel consumption during a selected period (split fuel consump-
tion).

3-38
Operation Explanation of Components

DEF Level Gauge

DEF level gauge indicates the remaining level of DEF.
If the indicator is in green range during operations, it is normal.
If the indicator comes close to (A) of red range during opera-
tion, check and add DEF.
(A) to (B): Red range
(A) to (C): Green range
When the indicator is in red range from (A) to (B), DEF level
caution lamp (1) lights up in red.
If DEF level further decreases after the lamp lights up in red,
the engine power is derated.
When remaining level of DEF cannot be detected, DEF level caution lamp (1) lights up in white.
REMARK
• Immediately after turning the starting switch to ON position and while the engine is running, DEF level cau-
tion lamp (1) lights up in white. However, this does not indicate abnormality.
• In cold weather, DEF level cannot be detected and DEF level caution lamp (1) lights up in white for approxi-
mately 1 hour. However, this does not indicate abnormality.
• Even if DEF level caution lamp (1) does not light up in white, it may take a long time for DEF level gauge to
display the correct position.
Note that the following cases are not abnormal:
• When DEF is added while the starting switch is kept at ON position.
• When the starting switch is turned to ON position immediately after adding DEF (within approximately
30 seconds).
Before adding DEF, turn the starting switch to OFF position. Wait for a while after adding, then turn the
starting switch to ON position.

3-39
Explanation of Components Operation

Monitor Switch

(1) Function switch (4) Pedal mode selector switch

(2) Buzzer cancel switch (5) Gear shift mode selector switch
(3) Operating mode selector switch (6) Reverse travel speed setting switch

Function Switches and Guidance Icons

• Function switches (1) at the bottom of the monitor display
consist of 6 switches (F1 to F6). The function of each
switch differs according to the content of each screen.
• On each screen, you can confirm the function of switches
(1) by guidance icons (2) displayed on top of the switch.
• While guidance icon (2) is not displayed, switch (1) does
not function even if it is pressed.
• Even if guidance icon (2) is pressed, it does not function.
Press function switch (1) directly under guidance icon (2)
to operate the function.
When the monitor display shows the standard screen, the types of guidance icons and functions of function
switches are as follows:
For the details of each function, see the detailed explanation of each item.
(O) Switch F1: Customize switch
(A) Switch F2: Multi-gauge selector switch

3-40
Operation Explanation of Components

(B) Switch F3: Camera image selector switch.

(C) Switch F4: Service meter / clock display selector switch

(D) Switch F5: Current Abnormality display switch

(Only while caution lamp is lit)
(E) Switch F5: Energy saving (ECO) guidance erase switch
(While ECO guidance is displayed)
(F) Switch F6: User menu display switch

Guidance icons and their functions differ with the contents of the displayed screen, but representative guidance
icons frequently used and their functions are as follows:
(G) Switch F1 or F3: Moves to the left item. (When on the left
end, it moves to the right end.)
(H) Switch F2 or F4: Moves to the right item. (When on the
right end, it moves to the left end.)

(I) Switch F3: Moves to the item below (forward). (When on the
last line, it moves to the first line.)
(J) Switch F4: Moves to the item above (backward). (When on
the first line, it moves to the last line.)

3-41
Explanation of Components Operation

(K) Switch F5: Cancels any change and returns to the previous
screen.
(L) Switch F6: Decides any selection and changes contents
and advances to the next screen.

REMARK
• Even if some guidance icons look the same, their display positions and corresponding function switches
may differ in accordance with the screens to be displayed.
• For the guidance icons and their functions not explained above, see the pages where the control methods
of respective screens are explained.

Buzzer Cancel Switch

Buzzer cancel switch is used to stop the alarm buzzer for the warning item where there is an abnormality.
The buzzer cannot be stopped according to the content of the
warning.

3-42
Operation Explanation of Components

Operating Mode Selector Switch

The operating mode selector switch is used for switching the
operating mode of the engine.
Normally, it is possible to perform all operations in E mode, and
this mode reduces fuel consumption.
Compared with E mode, P mode has more power, but the fuel
consumption increases.
When the starting switch is turned to ON position, the mode
used for the previous operation is selected.
The selected mode is displayed at the top of the screen.

Pedal Mode Selector Switch

The pedal mode selector switch is used to switch the pedal
mode between decelerator mode and brake mode.
If the decelerator/brake pedal is depressed in decelerator
mode, the travel speed and engine speed lower.
If the decelerator/brake pedal is depressed in brake mode, the
travel speed lowers but the engine speed does not lower.
Normally, select the decelerator mode. If you want to operate
the machine with reduced travel speed without sacrificing the
speed of work equipment, select the brake mode.
When the starting switch is turned to ON position, the decelera-
tor mode is selected.
The selected mode is displayed at the top of the screen.

Gear Shift Mode Selector Switch

The gear shift mode selector switch is used to switch the gear
shift mode between quick shift mode and variable shift mode.
When the starting switch is turned to ON position, the mode
used for the previous operation is selected.
The selected mode is displayed at the top of the screen.

REVERSE Travel Speed Control Switch

Reverse travel speed setting switch is used to set the reverse
travel speed.

3-43
Explanation of Components Operation

Function Switches
The operation of the function switches in the standard screen

Customize Switch
k CAUTION
To ensure safety, always stop the machine before operating the customize switch.

Press switch F1, and “Mode Select” screen is displayed.

On “Mode Select” screen, you can set and save the following
items as desired.
Item Contents of setting
Operating Mode Power/ Economy
Gear Shift Mode Quick shift/ Variable shift
Pedal Mode Decelerator mode/ Brake mode
Reverse Travel -1/0/+1/+2/+3 (5 levels)
Speed Setting
Load Graph Dis- ON/OFF
play
Blade Mode FAST/ NORMAL/ FINE
Steering Mode NORMAL/ FINE
1st Speed Setting -2/-1/0/+1/+2 (5 levels)
2nd Speed Set- -2/-1/0/+1/+2 (5 levels)
ting
3rd Speed Set- -2/-1/0 (3 levels)
ting

Operating Mode
Select “Operating Mode” on “Mode Select” screen, and press
switch F6.
Operating mode of engine can be switched in accordance with
the operation.
Operating mode can also be switched with the operating mode
selector switch.

3-44
Operation Explanation of Components

Gear Shift Mode

Select “Gear Shift Mode” on “Mode Select” screen, and press
switch F6.
Gear shift mode can be changed according to the work.
Gear shift mode can also be changed by the gear shift mode
selector switch.

Pedal Mode
Select “Pedal Mode” on “Mode Select” screen, and press
switch F6.
Pedal mode can be switched in accordance with the operation.
Pedal mode can also be switched with the pedal mode selector
switch.

REVERSE Travel Speed Settings

Select “Reverse Travel Speed Setting” on “Mode Select”
screen, and press switch F6.
Reverse travel speed can be selected out of 5 levels according
to the operation.
Reverse travel speed can also be set with the reverse travel
speed setting switch.

3-45
Explanation of Components Operation

Load Display
Select “Load Display” on “Mode Select” screen, and press
switch F6.
Display/Non-display of load graph can be switched.

Horizontal axis (X) indicates the time, and vertical axis (Y) indi-
cates the drawbar pull in the load graph.
Similarly to the ECO gauge, it is recommended to use in green
range (G).
The graphs on the screen are updated and scrolled to the left
at intervals of several seconds. (The latest information is dis-
played at the right end.)

3-46
Operation Explanation of Components

Blade Mode
Select “Blade Mode” on “Mode Select” screen, and press
switch F6.
Blade mode can be changed according to the operation.
By setting to “FAST” mode, starting of operation for RAISE and
LOWER becomes quick.
By setting to “FINE” mode, starting of operation for RAISE and
LOWER becomes smooth.
When the starting switch is turned to ON position, the mode
used for the previous operation is selected.
The selected mode is displayed at the top of the screen.

Steering Mode
Select “Steering Mode” on “Mode Select” screen, and press
switch F6.
Steering mode can be changed according to the work.
In NORMAL mode, tilt the joystick (steering, directional and
gear shift lever) to right or left until the operating effort be-
comes large, and the machine makes pivot turn.
Tilt the joystick (steering, directional and gear shift lever) further
from that position, and the machine will make counter-rotation
turn.
In FINE mode, tilt the joystick (steering, directional and gear
shift lever) to right or left further from the position where the operating effort becomes large, and the machine
makes pivot turn.
When the starting switch is turned to ON position, the normal mode is selected.
The selected mode is displayed at the top of the screen.

1st Travel Speed Setting

Select “1st Travel Speed Setting” on “Mode Select” screen, and
press switch F6.
1st travel speed in quick shift mode can be selected out of 5
levels according to the operation.
By setting the travel speed according to the operation in ad-
vance, gear shifting is not necessary when operating the joy-
stick (steering, directional and gear shift lever).
When the starting switch is turned to ON position, “0” is set. (It
returns to the preset 1st travel speed.)

When you want to set the travel speed to faster or slower than
preset 1st travel speed, press switch F3 or switch F4 to set the
travel speed.
You can increase or decrease the speed in 2 levels each.
(A) +2: Increases 2 levels from preset 1st travel speed
(B) +1: Increases 1 level from preset 1st travel speed
(C) 0: Preset 1st travel speed
(D) -1: Decreases 1 level from preset 1st travel speed
(E) -2: Decreases 2 levels from preset 1st travel speed

3-47
Explanation of Components Operation

2nd Travel Speed Setting

Select “2nd Travel Speed Setting” on “Mode Select” screen,
and press switch F6.
2nd travel speed in quick shift mode can be selected out of 5
levels according to the operation.
You can increase or decrease the speed in 2 levels each.
+2: Increases 2 levels from preset 2nd travel speed
+1: Increases 1 level from preset 2nd travel speed
0: Preset 2nd travel speed
-1: Decreases 1 level from preset 2nd travel speed
-2: Decreases 2 levels from preset 2nd travel speed
For details of the travel speed setting method, see “1st Travel Speed Setting”.

3-48
Operation Explanation of Components

3rd Travel Speed Setting

Select “3rd Travel Speed Setting” on “Mode Select” screen,
and press switch F6.
3rd travel speed in quick shift mode can be selected out of 3
levels according to the operation.
You can increase or decrease the speed in 1 level each.
0: Increases 1 level from preset 3rd travel speed
-1: Preset 3rd travel speed
-2: Decreases 1 level from preset 3rd travel speed
For details of the travel speed setting method, see “1st Travel
Speed Setting”.

3-49
Explanation of Components Operation

How to Set Each Item and Save Memory

1. Press the switch F3 or F4 on “Mode Select” screen to set
the yellow cursor to the target item of setting change, and
then press the switch F6.
The setting change screen for the selected item is dis-
played.

2. Press the switch F3 or F4 to move the yellow cursor to a

setting to change, and press the switch F6.
(The figure shows an example of the setting change
screen when “Operating Mode” is selected.)

3. After the setting change of each item is completed, press

the switch F2.
The memory saving screen is displayed.

4. Check the setting of each item (on the left of the screen).
5. Press the switch F3 or F4 to move the yellow cursor to a
memory number (“M1” to “M5”) to save, and press the
switch F6.
The setting is saved by the above operation.

3-50
Operation Explanation of Components

How to Call Memory

1. Press switch F1 on “Mode Select” screen.
The mode memory call screen is displayed.

2. Press switch F3 or F4 to move the yellow cursor to a mem-

ory number (“M1” to “M5”) to call out.
As the cursor is set to the number, the setting stored in the
memory is displayed in the right side of the screen.
3. Call out the selected setting by pressing switch F6.

3-51
Explanation of Components Operation

Camera Image Selector Switch

On the standard screen, press switch F3 to switch to the cam-
era image display.

Press switch F3 while camera image is displayed, and the

screen returns to the standard screen.
The screen cannot be returned to the standard screen, howev-
er, while the camera image is being displayed by the reverse
synchronization.

Other Mode Operations While Camera Image is Shown

Even when the camera image is displayed, it is possible to operate following modes.
• It is possible to change the operating mode by pressing
the operating mode selector switch.
When the operating mode is changed, the screen returns
automatically to the standard screen.

• It is possible to change the gear shift mode by pressing the

gear shift mode selector switch.

3-52
Operation Explanation of Components

• Press the reverse travel speed setting switch to set the re-
verse travel speed.

• It is possible to stop the alarm buzzer for the warning item

where there is an abnormality, by pressing the buzzer can-
cel switch.
Even if the buzzer cancel switch is pressed, the camera
image display screen neither switches to another screen
nor returns to the standard screen.
Depending on the warning, alarm buzzer does not stop
sounding by pressing the buzzer cancel switch.

• Press the pedal mode selector switch to change the pedal

mode.

Procedures Against Warning While Camera Image is Shown

If any error or warning occurs on the machine while the camera
image is displayed, the caution lamp flashes at the top left of
the screen.

3-53
Explanation of Components Operation

• If the caution lamp is displayed, press switch F3 to return

to the standard screen, and check the content of the error
or warning display.
While the caution lamp is flashing, if no lever is operated
for 10 seconds or more, the screen automatically returns
to the standard screen.
When the screen returns to the standard screen, the cau-
tion lamp at the top left of the screen goes out and an error
or a warning is displayed at the center of the screen.
The screen cannot be returned to the standard screen,
however, while the camera image is being displayed by the
reverse synchronization. Stop the machine to return the screen to the standard screen.
• If an error is displayed, move the machine, set it in a safe posture, then have inspection performed immedi-
ately.

3-54
Operation Explanation of Components

Service Meter/Clock Display Selector Switch

By pressing switch F4, you can switch the service meter and
clock display on the standard screen.

If you press switch F4 while the clock is displayed, the service

meter is displayed instead of the clock.
If you press switch F4 while the service meter is displayed, the
clock is displayed instead of the service meter.

3-55
Explanation of Components Operation

Multi Gauge Selector Switch

Multi-gauge display items can be switched by pressing the
function switch F2.

3-56
Operation Explanation of Components

Use Multi Gauge

The multi-gauge can display the following items.

Multi-gauge selection item Remarks

Engine speed There is a caution
Machine speed -
Work equipment pump pressure -
Battery voltage There is a caution
Drawbar pull -
Clock display -

An approximate value indicated by the multi-gauge is as fol-

lows.
Engine speed
(1) 500 rpm
(2) 1000 rpm
(3) 1500 rpm
(4) 2000 rpm
(5) 2750 rpm
(6) 3000 rpm
• (1) to (5): Green range
• (5) to (6): Red range
During operation, try to keep the pointer in green range.
Machine speed
(1) 0 km/h {0 MPH}
(2) 5 km/h {3.1 MPH}
(3) 10 km/h {6.2 MPH}
(4) 15 km/h {9.3 MPH}

Work equipment pump pressure

(1) 0 MPa {0 kgf/cm2, 0 PSI}
(2) 10 MPa {102 kgf/cm2, 1450 PSI}
(3) 20 MPa {204 kgf/cm2, 2900 PSI}
(4) 30 MPa {306 kgf/cm2, 4350 PSI}
(5) 40 MPa {408 kgf/cm2, 5800 PSI}
(6) 50 MPa {510 kgf/cm2, 7250 PSI}

3-57
Explanation of Components Operation

Battery voltage
(1) 0 V
(2) 15 V
(3) 20 V
(4) 25 V
(5) 30 V
(6) 31 V
• (1) to (2): Red range
• (2) to (5): Green range
• (5) to (6): Red range
When the pointer is in green range during operation, it is normal. If the pointer is in red range, charge during
engine running is not performed normally.
Stop the operation, move the machine to a safe place, and then ask your Komatsu distributor for the inspection
and maintenance.
Drawbar pull
(1) 0 W
(2) 0.2 W
(3) 0.4 W
(4) 0.6 W
(5) 0.8 W
(6) 1.0 W

Clock display
REMARK
12-hour or 24-hour system is available for clock display.

3-58
Operation Explanation of Components

User Menu Display Switch

On the standard screen, press switch F6 to display the user
menu screen on which you can make various settings for the
machine in the monitor display.

3-59
Explanation of Components Operation

User Menu
The user menu consists of the following kinds. Press switches
F1 and F2 to move to right and left for selecting menu screens.
(a) “Energy Saving Guidance”
(b) “Machine Setting”
(c) “Aftertreatment Devices Regeneration”
(d) “SCR Information”
(e) “Maintenance”
(f) “Monitor Setting”
(g) Mail Check
These menus (a) to (g) are for setting and confirming the fol-
lowing items:
For operations in each menu, see the detailed explanation pa-
ges of respective items.

(a) “Energy Saving Guidance”

• Check of operating record
• Check of ECO guidance record
• Check and reset of fuel consumption record
• Display setting

(b) “Machine Setting”

• Fan reverse mode
• Auto idle stop timer setting

(c) “Aftertreatment Devices Regeneration”

• Setting for regeneration disable
• Operation of manual stationary regeneration

3-60
Operation Explanation of Components

(d) “SCR Information”

• Check of DEF level
• Information on DEF system

(e) “Maintenance”
• Check and reset of various maintenance times

(f) “Monitor Setting”

• Screen Adjustment
• Screen Adjustment (camera)
• Clock adjustment
• Language selection
• ID key information
• Operator ID

(g) Mail Check

• Check of mail contents and reply to mail

Operation on User Menu Screen

On the user menu screen, it is possible to perform the following
operations with switches F1 to F6.

3-61
Explanation of Components Operation

F1: Moves to the left menu. When on the left end menu, it
moves to the right end menu.
F2: Moves to the right menu. When on the right end menu, it
moves to the left end menu.

F3: Moves to the next item (1 line below). When on the last
line, it moves to the first line on the next page.
F4: Moves to the previous item (1 line above). When on the
first line, it moves to the last line on the previous page.

F5: Returns the screen to the standard screen.

F6: Displays the setting screen for selected item.
• If no switch is operated for 30 seconds on the user menu
screen, the screen automatically returns to the previous
screen.

ECO Guidance
Each item of “Energy Saving Guidance” menu (a) is used for
displaying and setting the notification relevant to energy saving.

3-62
Operation Explanation of Components

See Operation Records

Select “Operation Records” (1) from “Energy Saving Guidance”
menu screen, then press switch F6.
On “Operation Records” menu, the working hours, Average
Fuel Consumption, Actual working hours, Ave. Fuel Consump-
tion (Actual Working), Fuel Consumption, Idling Hours and E
mode time ratio on daily basis or on a split measurement peri-
od basis are displayed.

Operation on the Operation Records Screen

On “Operation Records” screen, you can perform the following
operations by pressing switch F3 to F5.
F3: Displays the next page. When on the last page, it displays
the first page.
F4: Displays the previous page. When on the first page, it dis-
plays the last page.
F5: Returns the screen to “Energy Saving Guidance” menu
screen.

Examine ECO Guidance Record

Select “ECO Guidance Records” (2) from “Energy Saving Guid-
ance” screen, then press switch F6.
On the “ECO Guidance Records” menu, display the frequency
of display of the ECO guidance on a daily basis or during the
split measurement period.

3-63
Explanation of Components Operation

Operations on “ECO Guidance Records” Screen

Press switch F5 to perform the following operation on the “ECO
Guidance Records” screen.
F5: Returns the screen to the “Energy Saving Guidance”
screen.

REMARK
ECO guidance denotes displaying the guidance for energy sav-
ing operation. This display may appear on the standard screen
while the machine is in operation.

See Fuel Consumption Record

Select “Average Fuel Consumption Record” (3) on “Energy
Saving Guidance” screen, and then press switch F6.
On “Average Fuel Consumption Record” screen, the graph of
hourly average fuel consumption during Last 12 hours or the
graph of daily fuel consumption Last 7 days is displayed.

3-64
Operation Explanation of Components

Operation on “Average Fuel Consumption Record” Screen

On “Average Fuel Consumption Record” screen, it is possible
to perform the following operations with switches F1, F2, and
F5.
F1: Clears the graph data.
F2: Switches graphical displays of the average fuel consump-
tion.
F5: Returns the screen to “Energy Saving Guidance” screen.
REMARK
The displayed value of fuel consumption and fuel consumption
rate may differ from the actual value due to the operating con-
ditions of the customers (fuel used, weather or work contents,
etc.).

Changes of the Graph Shown

Press F2 on “Average Fuel Consumption Record” screen to
change the currently displayed graph to another.
REMARK
There are 2 types of graphs. One shows hourly average fuel
consumption during last 12 hours and the other is daily aver-
age fuel consumption during last 7 days. Switching between
them is available.

3-65
Explanation of Components Operation

Delete “Average Fuel Consumption Record”

1. When switch F1 (CLEAR) is pressed, the reconfirmation
screen shown in the figure is displayed.
2. When the switch F6 is pressed on the reconfirmation
screen, graphs of data during last 12 hours and last 7 days
are both deleted, and the screen returns to “Average Fuel
Consumption Record” screen.
REMARK
Press switch F5 to cancel the data deletion (clear) opera-
tion.

Change Display Setting

Select “Configurations” (4) on “Energy Saving Guidance”
screen, and then press switch F6.
On “Configurations” screen, following operations are available.
• Setting of the Average Fuel Consumption Display
• Switching of the Display/Non-display of ECO gauge and
drawbar pull gauge
• Setting of the ECO Gauge Display Fuel Target Value
• Switching of the Display/Non-display of the ECO Guidance
Display
• Switching of the Display/Non-display of the ECO Guidance
Display at Key OFF
Operations on “Configurations” Screen
On “Configurations” screen, it is possible to perform the follow-
ing operations with switches F3 to F6.
F3: Moves to the next item (1 line below). When on the last
line, it moves to the first line.
F4: Moves to the previous item (1 line above). When on the
first line, it moves to the last line.
F5: Returns the screen to “Energy Saving Guidance” screen.
F6: Displays the setting screen for selected item.

3-66
Operation Explanation of Components

Set Display of Fuel Consumption Gauge

It is possible to change the display of fuel consumption gauge
(5) and the setting of Display/Non-display.

1. Select “Average Fuel Consumption Display” (6) from “Con-

figurations” screen, then press switch F6.
On this screen, it is possible to perform the following oper-
ations with switches F3 to F6.
F3: Moves to the next item (1 line below). When on the last
line, it moves to the first line on the next page.
F4: Moves to the previous item (1 line above). When on
the first line, it moves to the last line on the previous
page.
F5: Cancels the setting and returns to “Configurations”
screen.
F6: Changes the setting and returns to “Configurations”
screen.
2. The “Average Fuel Consumption Display” screen appears.
• “1 Day”
Displays the average fuel consumption from 0:00 a.m.
of the day to 0:00 a.m. of the next day.
• “Split Time”
Displays the average fuel consumption during the split
measurement period.
Select “Split Time” to start the automatic measurement of fuel consumption.
• “Not Use”
Does not display the fuel consumption gauge.

3-67
Explanation of Components Operation

REMARK
When you select the split measurement, measurement stop
switch F1 (“STOP”) is displayed on the “Operation Records”
screen and the “ECO Guidance Records” screen.
When you stop the measurement, select “Operation Records”
(1) screen or “ECO Guidance Records” (2) screen on “Energy
Saving Guidance” menu (a).
Move to each screen, press measurement stop switch F1
(“STOP”).

3-68
Operation Explanation of Components

Change Display/Non-Display of ECO Gauge and Drawbar Pull Gauge

You can specify the item to be displayed on display (7) of the
standard screen.

1. Select “ECO Gauge display” (8) from “Configurations”

screen, then press switch F6.
2. The “ECO Gauge Display” screen appears.
“Traction”: Displays drawbar pull gauge (A) on the stand-
ard screen.
“Fuel Consump”: Displays ECO gauge (B) on the standard
screen.
“OFF”: Displays nothing on display (7).

On this screen, it is possible to perform the following operations

with switches F3 to F6.
F3: Moves to the next item (1 line below). When on the last
line, it moves to the first line on the next page.
F4: Moves to the previous item (1 line above). When on the
first line, it moves to the last line on the previous page.
F5: Cancels the setting and returns to “Configurations” screen.
F6: Changes the setting and returns to “Configurations” screen.

3-69
Explanation of Components Operation

Target Fuel Consumption Value in ECO Gauge Setting

It is possible to change the target fuel consumption value (the
upper limit value of the green range) of the ECO gauge (7).

1. Select “ECO Gauge Display Fuel Target Value” (9) on

“Configurations” screen, and press switch F6.

2. “ECO Gauge Display Fuel Target Value” appears.

On this screen, it is possible to perform the following oper-
ations with switches F3 to F6.
F3: Decreases the target fuel consumption value by 1 ℓ/h.
F4: Increases the target fuel consumption value by 1 ℓ/h.
F5: Cancels the setting change and returns to Configura-
tions screen.
F6: Changes the setting and returns the screen to Configu-
rations screen.

3-70
Operation Explanation of Components

Change Display/Non-Display of ECO Guidance

It is possible to change the setting of Display/Non-display of
ECO guidance (10).

1. Select “ECO Guidance display” (11) from “Configurations”

screen, then press switch F6.
2. “ECO Guidance Display” setting screen appears.
ON: Displays ECO Guidance (10) on the standard screen.
OFF: Does not display ECO Guidance (10) on the stand-
ard screen.

On this screen, it is possible to perform the following operations

with switches F3 to F6.
F3: Moves to the next item (1 line below). When on the last
line, it moves to the first line on the next page.
F4: Moves to the previous item (1 line above). When on the
first line, it moves to the last line on the previous page.
F5: Cancels the setting and returns to “Configurations” screen.
F6: Changes the setting and returns to “Configurations” screen.

3-71
Explanation of Components Operation

Change Display/Non-Display of Guidance When Key is Off

It is possible to change the setting of Display/Non-display of
guidance (12) when the starting key is turned off.

1. Select “ECO Guidance Display at Key OFF” (13) from

“Configurations” screen, then press switch F6.

2. The setting screen for “ECO Guidance Display at Key

OFF” appears.
ON: Displays ECO Guidance (12) on the end screen.
OFF: Does not display ECO Guidance (12) on the end
screen.
On this screen, it is possible to perform the following oper-
ations with switches F3 to F6.
F3: Moves to the next item (1 line below). When on the last
line, it moves to the first line.
F4: Moves to the previous item (1 line above). When on
the first line, it moves to the last line.
F5: Cancels the setting change and returns to Configurations screen.
F6: Changes the setting and returns the screen to Configurations screen.

3-72
Operation Explanation of Components

Machine Settings
Each item of this menu (b) is used for setting items of machine.

Reverse Hydraulic Fan

k WARNING
After stopping the engine, check around the engine for sticking dry leaves or dirt.
In particular, carefully check around the exhaust manifold, turbocharger, aftertreatment devices for
sticking dirt which can cause a fire.

The hydraulic fan reverse mode (fan reverse rotation) can be used to remove insects and dirt sticking to the
radiator core by blowing air inward the machine with the fan.
Before starting the hydraulic fan reverse, check that there is no combustible substance in the periphery which
may be sucked in the fan.
In a cold circumstance, perform the cleaning by fan reverse rotation within less than 5 minutes. If the fan re-
verse rotation is performed for a long time, DEF hose may freeze.
If the fan reverse operation is performed while the aftertreat-
ment devices regeneration display (A) displays that the regen-
eration is in operation, the engine speed may not increase
even if the fuel control dial is set to High idle (MAX) position,
but this is not a failure.
1. Place the parking brake lever and work equipment lock
lever in LOCK position.
2. Perform the engine warm-up operation.
If the warm-up operation is not performed, the air flow may
be insufficient.
3. After finishing the warm-up operation, set the fuel control
dial to Low idle (MIN) position.
4. Stop the engine.
5. Open the hydraulic tank inspection cover and fuel tank inspection cover.
6. Remove the undercover.
7. Turn the starting switch to ON position.
8. Select “Fan Reverse Mode” (1) on “Machine Setting” menu
(b) screen.

3-73
Explanation of Components Operation

9. Press switch F6.

If the parking brake lever or work equipment lock lever is in
FREE position or the engine is running, the screen shown
in the figure is displayed and the fan rotation is not re-
versed.

10. Press switch F6 when the fan reversing confirmation

screen is displayed.
When canceling the fan reversing operation, press switch
F5.

11. Since fan reverse rotation is set, start the engine.

After the engine is started, the fan rotates in reverse, and

the machine monitor screen displays as shown in the fig-
ure.

If the aftertreatment devices regeneration display (A) dis-

plays that the regeneration is in operation while the fan is
rotated in reverse, the engine speed may decrease to
1100 rpm, regardless of the position of the fuel control dial.
In this case, the fan speed decreases and sufficient air
flow for cleaning the radiator cannot be obtained. Accord-
ingly, wait under the current condition until aftertreatment
devices regeneration display (A) goes out.
After the lamp goes out, the fan can rotate in reverse by in-
creasing the engine speed.

3-74
Operation Explanation of Components

If the parking brake lever or work equipment lock lever is

set to FREE position while the fan is rotated in reverse, the
screen shown in the figure is displayed.
In this case, stop the fan reverse rotation by returning the
parking brake lock lever and work equipment lock lever to
LOCK positions or by pressing switch F5.

If fan rotates in reverse with high speed for 10 minutes or

more, engine speed lowers automatically in order to pro-
tect the hydraulic component, and the screen shown in the
figure may be displayed, but this is not a failure.

12. After finishing the work, press switch F5 and stop the fan
reverse rotation.
13. Set the fuel control dial to Low idle (MIN) position.

14. Turn the starting switch to OFF position to stop the engine.

3-75
Explanation of Components Operation

Auto Idle Stop Timer Setting

The auto idle stop function stops the engine automatically when the engine is operated continuously at idle with
the lock lever in LOCK position for a set time.
The auto idle stop function operates when the following conditions are satisfied.
• The engine is running normally.
• The parking brake lever and work equipment lock lever are in LOCK positions.
• The engine coolant temperature and hydraulic oil temperature are high, and there is no need of idling to
cool them.
• The engine is not in automatic warm-up operation.
• The exhaust gas aftertreatment devices are not being regenerated.
• The parts of DEF system are not in thawing control.
• The Fan Reverse Mode is not being operated.
You can change the set time to operate the auto idle stop function on “Auto Idle Stop Timer Setting” screen.
1. Select “Auto Idle Stop Timer Setting” (2) on “Machine Set-
ting” menu (b) screen, and then press switch F6.

2. Select the set time on the “Auto Idle Stop Timer Setting”
screen shown, and then press switch F6.
On “Auto Idle Stop Timer Setting screen”, it is possible to
perform the following operations with switches F3 to F6.
F3: Moves to the next item (1 line below). When on the last
line, it moves to the first line.
F4: Moves to the previous item (1 line above). When on
the first line, it moves to the last line.
F5: Cancels the selection and returns the screen to the
Machine Setting menu screen.
F6: Allocates the selected setting to that of the auto idle stop timer setting.
REMARK
• If you select “OFF”, auto idle stop function does not operate.
• You cannot select a time longer than that specified in the service menu.
3. When the idling time reaches 30 seconds before the set
time, the monitor returns to the standard screen and
changes to the countdown screen.
At this time, the engine speed is fixed to Low idle (MIN)
position.
If you set the parking brake lever or work equipment lock
lever to FREE positions, countdown stops and the screen
returns to the standard screen.

3-76
Operation Explanation of Components

4. When countdown reaches 0, the engine stops and the

screen changes to the “Auto Idle Stop in Operation”
screen.
5. To prevent battery discharging, turn off unnecessary
switches.
REMARK
While the auto idle stop is activated, only the engine is
stopped and the machine monitor, inverter, etc., as well as
the electrical components including the air conditioner, ra-
dio, lamps, and windshield wipers keep their states before
the engine is stopped.
To prevent battery discharging, turn the starting switch to
OFF position.
6. When restarting the engine, turn the starting switch as usual.

Aftertreatment Devices Regeneration

Each item of “Aftertreatment Devices Regeneration” menu (c)
is to make settings for the aftertreatment devices regeneration.

SCR Information
Each item in “SCR Information” menu (d) is for displaying the
information related to SCR and DEF.

3-77
Explanation of Components Operation

Maintenance Screen Setting

Each item of setting menu (e) on “Maintenance” screen is used
for displaying and setting the notification relevant to mainte-
nance.
The items on the “maintenance” display are as follows.
A B
Air Cleaner Cleaning or Change -
Coolant Change -
Fuel Prefilter Change 500
Engine Oil Change 500
Engine Oil Filter Change 500
Fuel Main Filter Change 1000
Final Drive Case Oil Change 1000
Hyd Oil Tank Breather Change 1000
Fuel Tank Breather Change 1000
DEF Tank Breather Change 1000
Hydraulic Oil Filter Change 2000
Hydraulic Oil Change 2000
HST Oil Filter Change 2000
KCCV Filter Change 2000
DEF Filter Change 2000
DEF Tank Washing 4500

A: Maintenance item
B: Default maintenance interval settings (h)
C: Time remaining until maintenance (h)
On “Maintenance” screen, it is possible to perform the following operations with switches F1 to F6.
F1, F2: Moves to the right and left menus.
F3: Moves to the next item (1 line below). When on the last line, it moves to the first line.
F4: Moves to the previous item (1 line above). When on the first line, it moves to the last line.
F5: Returns the screen to the standard screen.
F6: If this switch is kept pressed, the screen changes to the screen for resetting the remaining time to the main-
tenance for the selected item.
REMARK
When resetting the remaining time to the maintenance, keep switch F6 pressed for at least 1.5 seconds. If this
time is short, the switch operating sound can be heard, but the screen does not switch to the screen for reset-
ting the remaining time to the maintenance.
• If no switch is operated for 30 seconds on “Maintenance” screen, the screen automatically returns to the
standard screen.
• When the maintenance time caution lamp is lit on the standard screen, press switch F6 on the standard
screen and the screen automatically displays “Maintenance” screen.
• On “Maintenance” screen, if the time remaining to the maintenance for any item is less than 30 hours (initial
setting value), the remaining time display (c) is highlighted in yellow. If the time remaining to the mainte-
nance is less than 0 hours, display (c) is highlighted in red.

3-78
Operation Explanation of Components

• If you want to change the setting for the maintenance time or maintenance notice time (initial setting: 30
hours), consult your Komatsu distributor.
Operation on “Maintenance Due Time Reset” Screen
On “Maintenance” screen, if switch F6 is kept pressed for 1.5 seconds or more, the screen changes to “Mainte-
nance Due Time Reset” screen.
Reset the remaining time to the maintenance on this screen.
1. Press switch F6 on “Maintenance Due Time Reset”
screen.
The screen switches to the reconfirmation screen.
REMARK
• When canceling the reset, press switch F5. The
screen returns to “Maintenance” screen.
• On “Maintenance Due Time Reset” screen, if no
switch is operated for more than 30 seconds, the
screen automatically changes to “Maintenance”
screen.
2. The reconfirmation screen is displayed.
If switch F6 is pressed again, the remaining time is reset
and the screen switches to “Maintenance” screen.
REMARK
• When canceling the reset, press switch F5. The
screen returns to “Maintenance” screen.
• On the reconfirmation screen, if no switch is operated
for more than 30 seconds, the screen automatically
returns to “Maintenance” screen.

3-79
Explanation of Components Operation

Monitor Setting
Each item of “Monitor Setting”menu (f) is to make settings for
the monitor.

Screen Adjustment
Use the “Screen Adjustment” menu to adjust brightness of the monitor screen.
1. Select “Screen Adjustment” (1) on the “Monitor Setting”
menu screen, then press switch F6.

2. Use switches F2 to F6 to adjust brightness of the screen.

F2: Resets an adjusted value to default value.
F3: Moves the indicator to the left by one notch.
F4: Moves the indicator to the right by one notch.
F5: Cancels the change and returns to the “Monitor Set-
ting” menu screen.
F6: Accepts the change and returns to the “Monitor Set-
ting” menu screen.
REMARK
• If the light switch is at night mode ON, and the screen
is adjusted, it is possible to adjust the brightness of
the monitor screen (night mode).
• If the light switch is at day mode ON, and the screen is
adjusted, it is possible to adjust the brightness of the
monitor screen (day mode).
• As long as “*” mark is displayed in the upper right cor-
ner of the screen, brightness is automatically restric-
ted by the machine monitor to protect the liquid crys-
tal. Screen adjustment may not change the screen
brightness as long as “*” mark is displayed. However,
it is not an error.

3-80
Operation Explanation of Components

Camera Screen Adjustment

k CAUTION
Never drive the machine (in reverse) while watching only the camera screen. Be sure to visually check
the safety around the machine.
The guide lines indicate blade width lines and a line 5 m {16 ft 5 in} away from the rear of the machine.
When changing the blade, ask your Komatsu distributor for adjustment of the camera screen.

1. Select “Screen Adjustment (Camera)” on the “Monitor Set-

ting” menu screen.
2. Press switch F6.

On “Screen Adjustment (Camera)” screen, the following items

related to the camera screen can be set.
• Camera image screen brightness adjustment
• Camera view mode setting (Setting of Reverse Synchroni-
zation)
• Guide line display mode setting
On this screen, it is possible to perform the following operations
with switches F3 to F6.
F3: Moves to the next item (1 line below). When on the last
line, it moves to the first line.
F4: Moves to the previous item (1 line above). When on the first line, it moves to the last line.
F5: Cancels the change of setting and returns to the “Monitor Setting” menu screen.
F6: Changes the setting and returns to the “Monitor Setting” menu screen.

3-81
Explanation of Components Operation

Adjust Camera Image Brightness

1. Select “Brightness Adjustment” on “Screen Adjustment
(Camera)” menu.
2. Press switch F6.

3. Use switches F2 to F6 to adjust brightness of the screen.

F2: Resets an adjusted value to default value.
F3: Moves the indicator to the left by one notch.
F4: Moves the indicator to the right by one notch.
F5: Cancels the change and returns the screen to “Screen
Adjustment (Camera)” menu.
F6: Accepts change and returns to the “Screen Adjustment
(Camera)” menu.
REMARK
• If the light switch is at night mode ON, and the screen is
adjusted, it is possible to adjust the brightness of the moni-
tor screen (night mode).
• If the light switch is at day mode ON, and the screen is ad-
justed, it is possible to adjust the brightness of the monitor
screen (day mode).
• As long as “*” mark is displayed in the upper right corner of
the screen, brightness is automatically restricted by the
machine monitor to protect the liquid crystal. Screen ad-
justment may not change the screen brightness as long as
“*” mark is displayed. However, it is not an error.

3-82
Operation Explanation of Components

Set Display Mode

(Reverse Synchronization setting)
1. Select “Camera View Mode” on “Screen Adjustment (Cam-
era)” menu.
2. Press switch F6.

3. The “Camera View Mode” setting screen is displayed.

• “Normal”: Switch F2 of the function key is used to
change the screen to the camera screen.
• “Reverse Synchronization”: Camera screen is auto-
matically displayed when the gear shift lever is set to
reverse.
On this screen, it is possible to perform the following operations
with switches F3 to F6.
F3: Moves to the next item (1 line below). When on the last
line, it moves to the first line on the next page.
F4: Moves to the previous item (1 line above). When on the first line, it moves to the last line on the previous
page.
F5: Cancels the setting and returns to the “Screen Adjustment (Camera)” screen.
F6: Change the setting and returns to the “Screen Adjustment (Camera)” screen.

3-83
Explanation of Components Operation

Set Guide Line Display Mode

1. Select “Guide Line Display Mode” on “Screen Adjustment
(Camera)” menu.
2. Press switch F6.

3. “Guide Line Display Mode” setting screen is displayed.

• “OFF”: Guide lines (Outline (A), Center Line (B)) are
not displayed.
• “Outline”: Only outlines (A) that indicate the machine
width and the distance from the rear end of the ma-
chine are displayed.
• “Center Line”: Only machine center line (B) is dis-
played.
• “All”: Both of Outline (A) and Center Line (B) are dis-
played.
On this screen, it is possible to perform the following operations
with switches F3 to F6.
F3: Moves to the next item (1 line below). When on the last
line, it moves to the first line.
F4: Moves to the previous item (1 line above). When on the
first line, it moves to the last line.
F5: Cancels the setting and returns to the “Screen Adjustment
(Camera)” screen.
F6: Change the setting and returns to the “Screen Adjustment
(Camera)” screen.

3-84
Operation Explanation of Components

Clock Adjustment
“Clock Adjustment” menu is used to change the setting of the clock displayed on the standard screen of the
monitor.
1. Select “Clock Adjustment” (3) on “Monitor Setting” menu
screen.
2. Press switch F6.

3. The screen changes to “Clock Adjustment” screen.

The following 5 items can be changed.
(a): “GPS Synchronization”
(b): “Calendar”
(c): “Time”
(d): “12h/24h Mode”
(e): “Daylight Saving Time”
REMARK
• 2 items of “Calendar” (b) and “Time” (c) need to be
readjusted since they are reset after a long-term stor-
age.
• When the “GPS Synchronization” is set to ON, they
are automatically readjusted.
4. Perform the following setup procedure by operating switches F3 to F6 on “Clock Adjustment” screen.

GPS Synchronization Setting

On machines equipped with KOMTRAX, turning on “GPS Syn-
chronization” menu enables automatic setting of the monitor's
date and time in accordance with the clock of GPS.
F3: Moves to the next item (1 line below). Moves to the top line
when on the bottom line.
F4: Moves to the previous item (1 line above). Moves to the
bottom line when on the top line.
F5: Cancels change and returns to “Clock Adjustment” screen.
F6: Displays the setting screen for selected item.
REMARK
• When the machine is in the environment where the radio
waves from GPS cannot be received, such as inside of a
building, the automatic setting function may not work.
• While“GPS synchronization” menu is turned on, the menu
for “Calendar” (b) and “Time” (c) cannot be selected.

3-85
Explanation of Components Operation

Calendar Setting
Adjust the date of the monitor.
REMARK
As long as “GPS Synchronization” menu is turned on, “Calendar” menu is not selectable.
1. Select “Calendar” (b) on “Clock Adjustment” screen, then
press switch F6.

2. The “Calendar” screen is displayed.

When year display (A) is highlighted in yellow, operate the
switches as follows to change year display (A). If it is not
necessary to change the year setting, press switch F6.
F3: Calendar goes back 1 year.
F4: Calendar advances 1 year.
F5: Cancels change and returns the screen to “Clock Ad-
justment” screen.
F6: Proceeds to setting for month
3. When month display (B) is highlighted in yellow, operate
the switches as follows to change month display (B). If it is
not necessary to change the month, press switch F6.
F3: Calendar goes back 1 month.
F4: Calendar advances 1 month.
F5: Cancels change and returns to the year setting screen.
F6: Proceeds to setting for date.

4. When date display (C) is highlighted in yellow, operate the

switches as follows to change day display (C). If it is not
necessary to change the day, press switch F6.
F3: Calendar goes back 1 day.
F4: Calendar advances 1 day.
F5: Cancels change and returns to the month setting
screen.
F6: Accepts change and returns the screen to “Clock Ad-
justment” screen.

3-86
Operation Explanation of Components

Time Setting
Adjust the time of the monitor clock.
REMARK
As long as “GPS Synchronization” is turned on, “Time” menu is not selectable.
1. Select “Time” (c) on “Clock Adjustment” screen, then press
switch F6.

2. The “Time” screen is displayed.

When the hour display (D) is highlighted in yellow, operate
the switches as follows to change hour display (D). If it is
not necessary to change the hour setting, press switch F6.
F3: The time goes back 1 hour.
F4: The time advances 1 hour.
F5: Cancels change and returns the screen to “Clock Ad-
justment” screen.
F6: Proceeds to setting for the minute.
3. When minute display (E) is highlighted in yellow, operate
the switches as follows to change minute display (E). If it is
not necessary to change the minute, press switch F6.
F3: The time goes back 1 minute.
F4: The time advances 1 minute.
F5: Cancels change and returns to the time setting screen.
F6: Accepts change and returns the screen to “Clock Ad-
justment” screen.

3-87
Explanation of Components Operation

Change 12H/24H Display Mode

Choose either a 12-hour display (AM/PM) or a 24-hour display.
• 24-hour system display
• 12-hour system display (AM/PM)
1. Select “12h/24h Mode” (d) on “Clock Adjustment” screen,
then press switch F6.

2. “12h/24h Mode” screen appears.

F3: Moves to the next item (1 line below). Moves to the top
line when it is on the bottom line.
F4: Moves to the previous item (1 line above). Moves to
the bottom line when it is on the top line.
F5: Cancels the change and returns the screen to “Clock
Adjustment” screen.
F6: Accepts change and returns to “Clock Adjustment”
screen.

Daylight Saving Time (Summer Time) Setting

If “Daylight Saving Time” is turned on, the clock display becomes 1 hour forward. If “Daylight Saving Time” is
turned off, the clock display returns to the set time.
1. Select “Daylight Saving Time” (e) on “Clock Adjustment”
screen, then press switch F6.

2. The “Daylight Saving Time” screen is displayed.

F3: Moves to the next item (1 line below). Moves to the top
line when on the bottom line.
F4: Moves to the previous item (1 line above). Moves to
the bottom line when on the top line.
F5: Cancels change and returns to “Clock Adjustment”
screen.
F6: Accepts change and returns the screen to “Clock Ad-
justment” screen.
REMARK
Daylight saving time or summer time means moving the
clock forward an hour to take advantage of the fact that the
sun rises early in summer in our daily life.

3-88
Operation Explanation of Components

Language Settings
On “Language Setting” menu, it is possible to select the language used on the monitor display.
The languages that can be selected are as follows.
English, Japanese, French, Spanish, Portuguese, Italian, German, Swedish, Dutch, Danish, Norwegian, Fin-
nish, Icelandic, Czech, Hungarian, Polish, Slovak, Slovene, Romanian, Croatian, Estonian, Latvian, Lithuanian,
Bulgarian, Greek, Turkish, Serbian
1. Select “Language” (4) on the “Monitor Setting” menu, then
press switch F6.

2. Select the language to use for the display, then press

switch F6. The screen display changes to the selected lan-
guage.
On “Language” screen, it is possible to perform the follow-
ing operations with switches F3 to F6.
F3: Moves to the item below.
F4: Moves to the item above.
F5: Cancels change and returns to the “Monitor Setting”
screen.
F6: Accepts change and returns the screen to the “Monitor
Setting” screen.

3-89
Explanation of Components Operation

ID Key Information
ID number (A) of ID key inserted into the starting switch can be
checked with “ID key information” menu (5).

Operator ID
You can check and change the “Operator ID” which is under identification on the “Operator ID” menu.
The “Operator ID” menu is not displayed when the operator identification function is disabled.
REMARK
Contact your Komatsu distributor for details of the method of setting, changing, or canceling the operator identi-
fication function.

When Operator Identification Function is Available with SKIP

When the starting switch is ON and ID is inputted, the identified
ID is displayed in the column of “Operator ID” on the “Monitor
Setting” menu screen.

When the starting switch is ON and “SKIP” is selected, “****” is

displayed in the column of “Operator ID” on the “Monitor Set-
ting” menu screen.

1. Select “Operator ID” (5) on the “Monitor Setting” menu

screen, then press switch F6 for 1 second.

3-90
Operation Explanation of Components

2. The “Operator ID Change” screen is displayed.

• Input the already registered ID on the “Operator ID

Change” screen and press F6. Then, the identified ID
can be changed.
A message is displayed below and the screen returns
to the “Monitor Setting” menu screen.
On the “Monitor Setting” menu screen, the inputted ID
is displayed in the column of “Operator ID”.

• When you press switch F1 on the “Operator ID

Change” screen, a message is displayed below and
the screen returns to the “Monitor Setting” menu
screen.
On the “Monitor Setting” menu screen, as the same
way when the starting switch is ON and “SKIP” is se-
lected, “****” is displayed in the column of “Operator
ID”.
In this case, the operator ID is not identified.

• When you press switch F6 after inputting the ID which

is not registered to the “Operator ID Change” screen,
a message is displayed below and the screen returns
to the “Monitor Setting” menu screen.
In this case, the identified ID is not changed.
• On the “Operator ID Change” screen, if no switch is
operated for more than 30 seconds, the screen auto-
matically changes to the “Monitor Setting” menu
screen.
In this case, the identified ID is not changed.

3-91
Explanation of Components Operation

When Operator Identification Function is Available Without SKIP

When the operator identification function is available without
SKIP, the identified ID number is not displayed in the “Operator
ID” column of “Monitor Setting” screen.

1. Select “Operator ID” (5) on the “Monitor Setting” menu

screen, then press switch F6 for 1 second.

2. The “Operator ID Change” screen is displayed.

• Input the already registered ID on the “Operator ID

Change” screen and press F6. Then, the identified ID
can be changed.
A message is displayed below and the screen returns
to the “Monitor Setting” menu screen.

• When you press switch F6 after inputting the ID which

is not registered to the “Operator ID Change” screen,
a message is displayed below and the screen returns
to the “Monitor Setting” menu screen.
In this case, the identified ID is not changed.
• On the “Operator ID Change” screen, if no switch is
operated for more than 30 seconds, the screen auto-
matically changes to the “Monitor Setting” menu
screen.
In this case, the identified ID is not changed.

3-92
Operation Explanation of Components

Message Display
On machines equipped with KOMTRAX, you can see the mes-
sages from your Komatsu distributor on this User Message
menu (g).

When there is any message, the User Message (1) at the top
of the standard screen lights up.

Message is distinguished as follows according to the lighting

states of User Message (1).
Lights up in green (A): There is unread message.
Lights up in blue (B): There is any read message to which no
reply is made.
OFF: No messages
REMARK
• When the message display lights up in blue (B), it means
that no reply has been made yet to any read message to
your Komatsu distributor. Reply to the message in accord-
ance with the replying method mentioned below:
• If the starting switch is turned to OFF position when there
is any unread message, the message will be displayed on
the end screen, and when the monitor is started next time,
the message will change to a read message (the message
display: lights up in blue (B)).
• The message will be deleted when it becomes out of date
or when a new message arrives.

3-93
Explanation of Components Operation

See Message
1. On the standard screen, press switch F6.
When there is any message, message display (1) lights
up.
While message display (1) is lit, press switch F6, and the
mail confirmation menu (g) directly opens.
Select the mail confirmation menu (g), and you can read
the received message.

2. If a message requests reply, the “Numeric Input: []” box (2)

is displayed. Make any reply to the message.
REMARK
• (3) is the subject of the received message. When no
message is received, “No message.” is displayed in
place (3).
• (4) is the serial number of received messages.

Reply Message
1. Input the selected item number in the “Numeric Input: []” box (2) on the screen of mail confirmation menu
(g).
The selected item number is written in place (5) of the
message text.
• Input the number by using the monitor panel switch.
Each switch corresponds to the value shown on the
right side below the switch.
• If you input an incorrect number, press switch F5, and
you can clear an input character at a time.
• If switch F5 is pressed when the input column is blank,
the screen returns to the standard screen.
2. After inputting a selected item number, press switch F6.
3. When the message “Do you send Numeric Input?” is dis-
played in the column (2) of the mail confirmation menu (g)
screen, press switch F6 again. The input value will be sent
out.
If switch F5 is pressed when the message “Do you send
Numeric Input?” is displayed, the message reply screen
will appear. At this time, the previous input value will be
cleared.

3-94
Operation Explanation of Components

Switches

(1) Air conditioner switch (7) Engine shutdown secondary switch

(2) Cigarette lighter (24 V) (8) Starting switch
(3) Fuel control dial (9) Horn switch
(4) Rear lamp switch (10) Room lamp switch
(5) Headlamp switch (11) Wiper switch
(6) Foot heater switch

Starting Switch
Starting switch is used to start or stop the engine.
(A): OFF position
The key can be inserted or withdrawn. Switches for the electri-
cal system (except room lamp) are all turned off, and the en-
gine is stopped.
(B): ON position
Electric current flows through the charging and lamp circuits.
Keep the switch at this position while the engine is running.
(C): START position
This is the position to start the engine. Keep the key at this position during cranking and release it immediately
after the engine starts.
When the switch is released, it automatically returns to ON position (B).
(D): HEAT (preheating) position
This is the position to start preheating manually.
When the key is turned to HEAT (preheating) position (D), the HEAT pilot lamp lights up and preheating starts.
When the preheat pilot lamp changes from lighting to flashing, release the key immediately.
When the switch is released, it automatically returns to OFF position (A).
Turn the starting switch key to START position (C) and start the engine immediately.

3-95
Explanation of Components Operation

Fuel Control Dial

k WARNING
• When turning the fuel control dial to High idle (MAX) side while machine is stopped, check that the
joystick (steering, directional and gear shift lever) is in NEUTRAL position. If the fuel control dial is
turned to High idle (MAX) side while the joystick (steering, directional and gear shift lever) is in
FORWARD or REVERSE position, the machine moves off suddenly and this may lead to serious per-
sonal injury or death.
• When turning the fuel control dial to High idle (MAX) side while the joystick (steering, directional
and gear shift lever) is in FORWARD or REVERSE position, be careful of safety for the area around
the machine, and turn the dial slowly.

Fuel control dial is used to control the engine speed and out-
put.
(a) Low idle (MIN)
The position where the dial is turned fully to the left.
(b) High idle (MAX)
The position where the dial is turned fully to the right.
REMARK
• If the work is relatively low load operation and also does
not require the high speed travel, turn back the fuel control
dial a little to Low idle (MIN) direction from High idle (MAX)
position so that the fuel efficiency improves and the noise
is reduced.
• For last leveling operation or gravel spreading operation as
well, turn back the fuel control dial a little to Low idle (MIN)
direction from High idle (MAX) position so that the shoe
slip is reduced and the undercarriage life improves.

Cigarette Lighter
The cigarette lighter is used to light cigarettes.
When the cigarette lighter is pushed in, it will return to its origi-
nal position after a few seconds, so pull it out to use it.
If the cigarette lighter is removed, the socket can be used as an
120 W (24 V x 5 A) power source.
NOTICE
This cigarette lighter is for 24 V. Do not use it as a power
supply for 12 V equipment.
REMARK
Use the cigarette lighter while engine is running.

3-96
Operation Explanation of Components

Wiper Switch
The wiper switch operates the windshield wiper.
The wiper switches are as follows.
(A) LH: Left door
(B) FF: Front window
(C) RH: Right door
(D) RR: Rear window
(E) INT: Intermittent operation switch (for right and front doors)
REMARK
If the wiper blade is locked for some reason, the wiper stops
automatically.
The wiper starts again automatically after a certain period of
stop. Be sure to remove the cause of stop, however.
Examples of causes of stop
• Long operation while glass is half dry
• Foreign material caught in arm or blade
• Snow or ice sticking to arm or blade
This switch is also used as the window washer switch.
The switch is operated as follows.
Switches (LH), (FF), (RH), and (RR)
(a) ON position
The wiper operates.
(b) Washer operating position
While the switch is depressed, the washing water is sprayed
and wiper operates at the same time.
When the switch is released, it returns to (a) position, washing
water stops, and only wiper operates.
(c) OFF position
The wiper stops.
Switch (INT)
(a) ON position
The wipers on right and left door operate intermittently.
(b) OFF position
The wipers on right and left door operate continuously.

3-97
Explanation of Components Operation

Horn Switch
If you press the horn switch, the horn sounds.
The horn switch is installed at the rear of the blade control lever
on the right of the operator's seat.

Head Lamp Switch

The headlamp switch is used to light up the head lamp and
monitor illumination.
(A) Night position
Lamps light up and monitor illumination is set to night mode.
(B) Day position
Lamps light up and monitor illumination is set to day mode.
(C) OFF position
Lamps go out.
(The monitor illumination is set to day mode.)

Rear Lamp Switch

Use the rear lamp switch to light up the rear lamp.
(A) ON position
Rear lamp lights up.
(B) OFF position
Rear lamp goes out.

Room Lamp Switch

NOTICE
If the room lamp is left to be turned on, the batteries may be exhausted. Always turn the switch to OFF
position after using room lamp.
Use room lamp switch to light up the room lamp.
ON position
Lights up
OFF position
OFF
The room lamp lights up even when the starting switch is at
OFF position.

3-98
Operation Explanation of Components

Engine Shutdown Secondary Switch

NOTICE
The engine shutdown secondary switch is used to stop the engine when the starting switch is turned to
OFF position but the engine does not stop.
• Use the engine shutdown secondary switch only in an emergency.
Immediately ask your Komatsu distributor for repair of the problem.
• If this switch is set to the “STOP ENGINE” position by mistake while the machine is operating nor-
mally, “Engine Shutdown Secondary SW In Operation” is displayed on the machine monitor.
If “Engine Shutdown Secondary SW In Operation” is displayed on the machine monitor, check that
the switch cover is closed and the switch is in the “NORMAL” position. If not, set it to the “NOR-
MAL” position.
1. Raise cover (C) and open it.

2. Turn the engine shutdown secondary switch to upper posi-

tion (a) and the engine stops.
(a) STOP ENGINE
When abnormal (switch is set to upper position)
(b) NORMAL
When normal (switch is set to lower position)

• When cover (C) is closed, the engine shutdown secondary switch automatically returns to the NOR-
MAL position (b).
• When the starting switch is turned to ON position
while the engine shutdown secondary switch is in the
STOP ENGINE position (a), “Engine Shutdown Sec-
ondary SW In Operation” is displayed on the machine
monitor.
If this screen is displayed, return the engine shutdown
secondary switch to the NORMAL position (b).

3-99
Explanation of Components Operation

Foot Heater Switch

Foot heater (a) is operated by foot heater switch.

(A) LO position
Low
(B) Center position
OFF
(C) HI position
High
The lamp inside the switch lights up by operating the switch.

Air Conditioner Switch

Air conditioner switch is used to control the air conditioner.
(A) Air-conditioning mode selector switch
(B) Blower selector switch
(C) Temperature control switch
For details, see “Handle Air Conditioner”.

3-100
Operation Explanation of Components

Control Levers and Pedals

(1) Work equipment lock lever (4) Decelerator/brake pedal

(2) Parking brake lever (5) Blade control lever
(3) Joystick (steering, directional and gear shift lever)

Blade Control Lever

NOTICE
If you feel the play of blade control lever is large, consult your Komatsu distributor for inspection.
The blade control lever is used for lifting, tilting and angling of the blade.
Lifting Operation
(A) RAISE
Blade rises.
(B) HOLD
Blade is stopped and held in this position.
(C) LOWER
Blade lowers.
(D) FLOAT button
The blade moves freely under external force.

3-101
Explanation of Components Operation

REMARK
• The blade is not set in FLOAT mode until the lever is moved to LOWER stroke end.
To set the blade in FLOAT mode, move the lever to LOWER stroke end while pressing FLOAT button (D).
• When FLOAT mode is set, the electronic sound of beep notifies that FLOAT mode is set.
After that, if you release the blade control lever, it returns to HOLD position (B), but FLOAT mode is kept.
• FLOAT mode is canceled when the blade control lever is moved to RAISE or LOWER side from HOLD po-
sition (B).
When FLOAT mode is canceled, electronic sound of beep is heard.
Tilt Operation
(E) LEFT tilt
Blade tilts leftward.
(B) HOLD
Blade is stopped and held in this position.
(F) RIGHT tilt
Blade tilts rightward.
Machine Tilting amount (mm {in})
model
Narrow blade Width blade High capacity
blade
D51EX 425 {16.7} 470 {18.5} –
D51PX – 470 {18.5} 470 {18.5}

Angle Operation
Operate angle switch (L) forward and backward to angle the
blade.
(G) LEFT angle
Blade is angled leftward.
(B) HOLD
Blade is stopped and held in this position.
(H) RIGHT angle
Blade is angled rightward.
REMARK
• If the angling operation is performed while the blade con-
trol lever is not in HOLD position (while either or both of
lifting and tilting operations are performed), all of those op-
erations can be continued, but the moving speed of the
blade is lowered.
Select the operations according to the type of operation.
• If the lifting or tilting operation is performed while angling
operation is performed, the machine moves similarly to the
above.

3-102
Operation Explanation of Components

Decelerator/Brake Pedal
k WARNING
• When passing over the top of a hill or when dumping soil from a cliff, the load on the machine will
suddenly be reduced and the travel speed will increase. This situation is dangerous.
Depress the decelerator/brake pedal to lower the travel speed.
• On a flat ground, you can stop the machine by using the decelerator/brake pedal. However, this
does not mean that brake is applied.
On a downhill, even if you depress the decelerator/brake pedal and lower the engine speed, ma-
chine may travel.
Be extremely careful of this on a downhill.
• When driving down the slope, select the speed range at which engine brake is effective, and de-
press the decelerator/brake pedal as needed.

The decelerator/brake pedal is used to lower the engine speed

or lower the travel speed to stop the machine.
Depress this pedal to lower the travel speed before changing
the travel direction.
When you depress the decelerator/brake pedal, it stops at the
point where the depressing effort increases. If you depress it
further, the mechanical brake is applied.

3-103
Explanation of Components Operation

Parking Brake Lever

k WARNING
• When leaving the operator's seat, set the parking brake lever securely to LOCK position (L)
When the parking brake lever is not in LOCK position (L), if the joystick (steering, directional and
gear shift lever) is touched by accident, it may lead to serious personal injury or death.
• If the parking brake lever is not in LOCK position (L) securely, the parking brake may not be locked.
Check that the parking brake lever is under the state in the figure.
• When parking the machine, always set the parking brake lever to LOCK position (L).
• When pulling up or pushing down the parking brake lever, be careful not to touch the joystick
(steering, directional and gear shift lever).
• Check that your clothes do not get caught by the joystick (steering, directional and gear shift lever).
• When the parking brake lever is operated, the brake is applied even in traveling.
Do not operate the parking brake lever in traveling except in emergency, otherwise, machine stops
abruptly and it is dangerous.

The parking brake lever is the lever to control the parking

brake.
Be sure to operate the parking brake lever by holding the oper-
ating portion on the top.
Push down the parking brake lever and it will be set in LOCK
position (L).
(L) LOCK position:
The parking brake is applied.
(F) FREE position:
The parking brake is released.
REMARK
• When setting the parking brake lever to LOCK position, (L) return the joystick (steering, directional and gear
shift lever) to N (NEUTRAL) position.
• When starting the engine, set the parking brake lever to LOCK position (L).
When the parking brake lever is not in LOCK position (L), the limit switch is actuated, and the engine does
not start.

3-104
Operation Explanation of Components

Work Equipment Lock Lever

k WARNING
• When standing up from the operator's seat, set the work equipment lock lever securely to LOCK po-
sition (L).
If the work equipment lock lever is not at LOCK position (L) and the blade control lever is touched
by mistake, it may lead to serious accident.
• If the work equipment lock lever is not set securely to LOCK position (L), the lock may not be ap-
plied.
Check that the work equipment lock lever is under the state in the figure.
• When parking the machine or performing the maintenance, always lower the work equipment to the
ground, and then set the work equipment lock lever to LOCK position (L).
• When pulling up or pushing down the work equipment lock lever, be careful not to touch the blade
control lever.
• Check that your clothes do not get caught by the blade control lever.

The work equipment lock lever is a locking device of the blade.

Be sure to operate the work equipment lock lever by holding
the operating portion on the top.
Push down the work equipment lock lever and it will be set in
LOCK position (L).
(L) LOCK position:
You cannot operate the work equipment control lever
(F) FREE position:
The work equipment can move by operating the work equip-
ment control lever.
REMARK
When starting the engine, always set the work equipment lock lever to LOCK position (L) in order to secure the
safety.
If the work equipment lock lever is not in LOCK position (L), the limit switch is actuated and the engine will not
start.

3-105
Explanation of Components Operation

Joystick (Steering, Directional and Gear Shift Lever) (PCCS Lever)

Perform forward/reverse switching operation, steering opera-
tion, and counter-rotation turn operation by using the joystick
(steering, directional and gear shift lever).
REMARK
PCCS: Palm command control system
(Electronic steering system)

Forward/reverse switching operation

(A) FORWARD
(N) NEUTRAL
(B) REVERSE
Move to the front to travel forward; move to the rear to travel in
reverse.

Steering operation
(L) Turn LEFT
(N) NEUTRAL
(R) Turn RIGHT
When the lever is tilted halfway in the direction you are turning
while it is tilted in FORWARD or REVERSE, the machine turns.
If the lever is tilted rightward or leftward until operating effort
becomes large, turning radius decreases from the one at loose
turn.

REMARK
• When steering mode is NORMAL mode, if lever is tilted to
the position where the operating effort to right or left be-
comes large, the machine makes pivot turn. When steering
mode is FINE mode, even if lever is tilted to the position
where the operating effort to right or left becomes large,
the machine does not make pivot turn.
Tilt the lever further, and the machine makes pivot turn.
• If the lever is released during steering operation, it returns
to (A) or (B), and the machine travels straight.
• If you perform steering operation by supporting your hand
with lever guide (G), performance of steering operation im-
proves.
Counter-rotation turn operation
During steering operation, if lever is tilted further from the position where the operating effort becomes large,
right and left tracks turn contrary direction to each other, and the machine makes counter-rotation turn.

3-106
Operation Explanation of Components

Gear shift operation

The speed range is shifted by pressing switches (U) or (D)
while the joystick (steering, directional and gear shift lever) is in
FORWARD or REVERSE position.
(U) UP switch: The speed range is shifted up by 1 step each
time this switch is pressed.
(D) DOWN switch: The speed range is shifted down by 1 step
each time this switch is pressed.
When the starting switch is turned to ON position, the speed
range is automatically set to 1st.
As the work load increases, the travel speed gradually decrea-
ses, and the gear is shifted down. When the work load becomes light again, the gear is shifted up to the set
travel speed.
Even if gear is shifted down by automatic shifting, speed range display does not change.
REMARK
When the gear is shifted, the current speed range is displayed
in the speed range display section of the machine monitor.
(Example)
Neutral: “N” is displayed in the display section.
Forward 2nd: “F2” is displayed in the display section.
Reverse 3rd: “R3” is displayed in the display section.
When the parking brake lever is locked, “P” is displayed.

3-107
Explanation of Components Operation

Other Equipment
Door Open Lock
Use the door lock to fix the door in position after opening it.
1. Push the door against the door catch (1).
The door is fixed to the catch.

2. To release the door, move lever (2) inside the cab to the front of the cab.
The catch releases.
NOTICE
• When keeping the door open, fix it securely to the
catch.
• Always close the door when traveling or performing
operations. If doors are left open, they may be broken.
• Keep the door locked open securely. The doors may
be closed by vibration.

Sash Glass Intermediate Lock

When working with the cab sash glass open, use this lock to
prevent the glass from chattering.
• When the lever is in FREE position (F), the glass can be
opened or closed.
• When the lever is in LOCK position (L), the glass is held in
position.

3-108
Operation Explanation of Components

Cap and Cover with Lock

Use the starting switch key to open and close the locks on the caps and covers.
Insert the key as far as it will go to the shoulder (A) and turn it.
If the key is turned when it is not inserted all the way to the
end, it may break.

Cup Holder
This is for keeping a beverage can, cup, etc.
If you put them on the other place than cup holder, they will fall
down and remaining liquid inside may get around part or ma-
chine dirty.
Use it for keeping a beverage can, cup, etc. with liquid inside.

Ashtray
NOTICE
While removing the ashtray, if it is stuck in the console cover and hard to be removed, open the lid of
ashtray, and then hold the ashtray body and twist it right and left to remove.
If you hold the lid of ashtray and twist it, the ashtray may break.
This is on the left side of the operator's seat.
Always extinguish your cigarette before putting it in the ashtray,
and be sure to close the lid.

3-109
Explanation of Components Operation

Lunch Box Fixing Belt

This is the place for lunch box.
Fix the lunch box with belt.
This can be used for other things than lunch box. Make efficient
use of this.

3-110
Operation Explanation of Components

Power Supply Outlet

Power Supply Inside the Cab
24 V power supply
NOTICE
Do not use this as a power supply for 12 V equipment.
This will cause failure of the equipment.
If cigarette lighter (1) is removed, its socket can be used as a
power source.
The capacity of the cigarette lighter is 120 W (24 V x 5 A).
REMARK
Use this power source while engine is running.
12 V power supply
(2 places)
The capacity of this accessory socket (2) is 144 W (12 V x 12 A).
• When it is used at one place: 144 W (12 V x 12 A)
• When it is used at 2 places: 144 W in total
REMARK
Use this power source while engine is running.
Power Supply on the External Side of the Cab
24 V power supply
NOTICE
• Do not use this as a power supply for 12 V equipment.
This will cause failure of the equipment.
• Do not install equipment which exceeds 120 W (24 V x
5 A).
Open the hydraulic tank inspection cover on the left side of the
machine, and the connector (3) for taking out auxiliary power
supply is seen.
(Connector AUX1 can be used.)

3-111
Explanation of Components Operation

Fuse
NOTICE
When replacing the fuse, be sure to turn the starting switch to OFF position and, after confirming that
the system operating lamp is not lit, set the battery disconnect switch key to OFF position.
• The fuses protect the electrical component and wiring from burning out.
• If the fuse becomes corroded, or looks white powdery, or the fuse is loose in the fuse holder, replace the
fuse.
• Replace the fuse with the one of the same capacity.
Remove fuse box cover (1) under the left side of the operator's
seat, and fuse boxes (A) and (B) are seen.

Fuse box (C) is installed to the overhead panel.

3-112
Operation Explanation of Components

Fuse Capacities and Circuit Names

Fuse Box (A)

No. Fuse ca- Name of circuit

pacity
(1) 30 A Front lamp and rear lamp
(2) 10 A Horn and preheater
(3) 15 A Foot heater
(4) 30 A Air conditioner
(5) 10 A Machine controller 1
(6) 15 A Air suspension seat and winch
(7) 30 A Cab power supply 1
(8) 30 A Cab power supply 2
(9) 15 A Starting switch
(10) 30 A Engine controller
(11) 20 A Spare power supply
(12) 20 A Spare
(13) 5A Key accessory (engine)
(14) - -
(15) 10 A Machine controller 2
(16) 10 A Monitor panel
(17) 5A System operating lamp
(18) 10 A Service connector
(19) 10 A Continuous power supply for cab
(20) 10 A Key accessory

Fuse Box (B)

No. Fuse ca- Name of circuit

pacity
(1) 10 A Smart sensor relay 1
(2) 20 A Smart sensor relay 2
(3) 20 A DEF heater relay 1
(4) 10 A DEF heater relay 2
(5) - -
(6) - -

3-113
Explanation of Components Operation

Fuse Box (C)

No. Fuse ca- Name of circuit

pacity
(1) 10 A Radio
(2) 20 A Additional working lamp
(3) 20 A Cigarette lighter and 12 V socket
(4) 10 A Radio and lamp
(5) 10 A Front windshield wiper and rear windshield
wiper
(6) 10 A R.H. and L.H. door windshield wipers

3-114
Operation Explanation of Components

Fusible Link
NOTICE
When replacing the fusible link, be sure to turn the starting switch to OFF position and, after confirming
that the system operating lamp is not lit, set the battery disconnect switch key to OFF position.
When the starting switch is turned to START position, if the starting motor does not operate, any of the electrical
component in the operator's cab does not work, or the preheater does not work, a fusible link built in the wiring
harness is suspected to be disconnected. Check and replace the fusible link.
Open the hydraulic tank inspection cover on the left side of the
machine and then open the fusible link case cover, and you
see the fusible links (1) and (2).
Remove the engine side cover on the right bottom side of the
machine, open the fusible link case cover, and you see the fusi-
ble links (3) and (4).
No. Fuse ca- Name of circuit
pacity
(1) 120 A Main power supply
(2) 120 A Continuous power supply
(3) 120 A Ribbon heater
(4) 120 A Alternator

REMARK
A fusible link refers to the large-sized fuse installed in the high
current flow part of the circuit.
It protects the electrical components and wiring from burning, in
the same way as an ordinary fuse.

3-115
Explanation of Components Operation

Tool Box
It is provided inside the hydraulic oil tank inspection cover on
the left side of the machine.
Store the tools in it.

Grease Pump Holder

It is provided inside the hydraulic oil tank inspection cover on
the left side of the machine.
Install the grease pump to the grease pump fixing holder and
fix it securely with the rubber band.
After using the pump, wipe off the grease from its outside.

Fire Extinguisher
(if equipped)
It can be installed at the rear part of the operator's seat.
Mounting bracket (optional) is necessary for installation.
For details of the parts necessary for installation, consult your
Komatsu distributor.
The directions are described on the nameplate affixed to the
fire extinguisher. Just in case, carefully read and understand
them beforehand.

Shovel Holder
(Machine with shovel holder)
This can be used for storing a shovel with a rounded blade.
1. When storing a shovel, fix it with stopper (1) and holder
(2).
2. Tighten the adjustment nut (3) so the shovel does not
move.

3-116
Operation Explanation of Components

First Aid Kit

(if equipped)
It can be installed at the rear part of the operator's seat.
For details of the parts necessary for installation, consult your
Komatsu distributor.

3-117
Explanation of Components Operation

Battery Disconnect Switch

k CAUTION
• Do not operate the battery disconnect switch while the engine is running.
The large current generated by the alternator may burn the electric parts and cause a fire.
Operate the battery disconnect switch only when the engine is stopped.
• If the battery disconnect switch is turned to OFF position, always remove the switch key.
If someone turns the key to ON position carelessly, this is extremely dangerous.

NOTICE
• Keep the battery disconnect switch in ON position except the following cases.
• When the machine is stored for a long time (more than a month)
• When repairing the electrical system
• When performing electric welding
• When handling the battery
• When replacing the fuse, etc.
• Do not turn the battery disconnect switch to OFF position while the system operating lamp is lit. If
the battery disconnect switch is turned to OFF position while the system operating lamp is lit, the
data in the controller will be lost and system abnormality may occur.
• If this switch is turned to OFF position, all the electrical system is cut out and the functions of KOM-
TRAX stop. In addition, the time information of the clock and the radio tuning information may be
lost. In this case, set the information again by referring to “Clock Adjustment” and “HANDLE RA-
DIO”.
Battery disconnect switch (1) is used to cut out the electricity
from the battery.
It is provided inside the hydraulic oil tank inspection cover on
the left side of the machine.
Open the rubber cover (2), and the battery disconnect switch
(1) is seen.
REMARK
Operate this switch while the system operating lamp (3) is not
lit.

3-118
Operation Explanation of Components

(O): OFF position

Battery disconnect switch key (1) can be pulled out (and inser-
ted) and the current from the battery is cut out.
(I): ON position
The current from the battery flows into the circuit.
Before starting the machine, be sure to set the switch to this
position.

System Operating Lamp

System operating lamp (1) indicates that the controller moun-
ted on the machine is turned on.
System operating lamp (1) lights up when the controller is
turned on.
Usually, it goes out in 5 to 6 minutes after the starting switch is
turned to OFF position.
Before operating the battery disconnect switch, check that sys-
tem operating lamp (1) is not lit.
NOTICE
If the battery disconnect switch is turned to OFF position
while the system operating lamp is lit, the data in the con-
troller will be lost and system abnormality may occur.
REMARK
• Even if the starting switch is in OFF position, the controller may operate. The system operating lamp lights
up in this case, but it is not abnormal.
• After the starting switch has been turned off, the system operating lamp may stay lit for a long time.
In such case, consult your Komatsu distributor.
• While DEF system devices are operating, the system operating lamp lights up to return DEF to the tank.
Do not turn the battery disconnect switch to OFF position while the system operating lamp is lit.
• The system operating lamp may look slightly luminous in the dark even when it is not lit. It is due to the
minute leakage of current and this is not an abnormal phenomenon.

3-119
Explanation of Components Operation

Radiator Grille
Open and close the radiator grille as needed in check and maintenance.

How to Open and Close Radiator Grille

k WARNING
• Before opening and closing the radiator grille, stop the engine and check that the fan is stopped.
If you touch the rotating fan, it will cause serious personal injury or death.
• Be careful not to get your finger caught in the gap between the radiator grille and tank while open-
ing and closing the radiator grille.
• When opening the radiator grille, check that it is locked securely. Check the lock and link part as
well for abnormality.
• Be careful not to hit your head, etc. against radiator grille when opening it.
• Check the hose and piping which moves with radiator grille for crack and other damage.

Procedure to Open Radiator Grille

1. Remove bolts (1) (2 pieces) under the radiator grille.

2. Pull the radiator grille backward and push it upward.

3. Open the radiator grille to the maximum opening position,
check that it is locked, and then release it.

3-120
Operation Explanation of Components

Procedure to Close Radiator Grille

NOTICE
Radiator grille cannot be closed unless it is unlocked. If you try to close the radiator grille without un-
locking, it may break.
1. Lift up the radiator grille, and push the lock releasing bar
(2) to the direction of arrow.
The lock is released.

2. Tighten the bolts (1) (2 pieces) on the lower part of the ra-
diator grille.

Dust Indicator
This device notifies the operator of clogging of air cleaner ele-
ment.

3-121
Explanation of Components Operation

Handle ID Key
(if equipped)
The starting switch keys are ID keys which have built-in IC chips, and you can start the engine only with the
usual keys (black) registered in the machine.

ID Key Types
Usual key
ID key used usually to start the engine
(Black) (1)
ID key used to register or delete usual keys
Registration key
(black) (1) in or from the machine
(Gray) (2)
(You cannot start the engine with this key)

NOTICE
• If you lose the registration key (gray), you cannot reg-
ister or delete the usual keys (black). Keep the regis-
tration key (gray) carefully.
• If a registered key (black) is stolen or you lose it, de-
lete it immediately. You cannot start the engine with a
usual key (black) if it is deleted from the machine.

3-122
Operation Explanation of Components

REMARK
• Do not use 2 or more ID keys overlapped each other. The
machine may not be able to start the engine since it may
not be able to recognize the ID correctly. (In this case, the
“ID Key Not Registered” screen is displayed on the ma-
chine monitor.)
When using a ID key, keep it apart from the other ID keys.
• You cannot start the engine with a key having no built-in IC
chip, registration key (gray), or usual key (black) which is
not registered in the machine.
• If the ID key system has any abnormality, the “ID Key Sys-
tem Abnormality” screen is displayed. If this screen is dis-
played, call your Komatsu distributor.

3-123
Explanation of Components Operation

Procedures to See ID Number of Registered Normal Key (Black)

1. Insert the usual key (black) in the starting switch and turn it
to ON position.
When the standard screen is displayed, press switch F6.

2. Operate switches F1 and F2 to display “Monitor Setting”

menu (A).
You can confirm the ID No. of the usual key currently inser-
ted in the starting switch on the ID No. display portion (C)
in “ID Key Information” item (B).

Procedures to Show ID Numbers of All the Registered Normal Keys (Black)

1. Insert registration key (gray) in the starting switch and turn
it to ON position, and the “ID Key Setting” screen is dis-
played on the machine monitor.

2. Press switch F6, and the ID No. list of the registered ID

keys (normal keys) is displayed.
(It may take time a little to display the list.)

3-124
Operation Explanation of Components

Procedures to Delete ID Number of Registered Normal Key (Black)

1. After the “ID Key List” screen is displayed, select the ID
No. of a usual key which you want to delete and hold down
switch F6 for 2 seconds or more. The “Deletion of Regis-
tered Key” screen is displayed.

2. Press switch F6 “Yes” on the “Deletion of Registered Key”

screen, and the confirmation screen for deletion of the reg-
istered key is displayed.

3. Press switch F6 “Yes” again on the confirmation screen for

deletion of the registered key, and the registration is de-
leted.
4. When the registration is deleted, the screen returns auto-
matically to the “ID Key List” screen. Check that the ID No.
you selected is deleted.

3-125
Explanation of Components Operation

Procedures to Delete ID Numbers of All the Registered Normal Keys (Black)

You can delete the keys registered in the machine all together.
1. Insert registration key (gray) in the starting switch and turn
it to ON position (B) to display the “ID Key Setting” screen
on the machine monitor.

2. Turn the registration key (gray) to OFF position (A) and

then to ON position (B) 5 times within 10 seconds, accord-
ing to the direction shown on the screen.

REMARK
If the operation of the starting switch is not finished within 10
seconds or the registration is not deleted normally, the mes-
sage of “Deletion of all the keys failed.” is displayed on the ma-
chine monitor.
If this screen is displayed, repeat the operation from step 1.

3-126
Operation Explanation of Components

Procedures to Register ID Number of New Normal Key (Black)

1. Insert registration key (gray) in the starting switch and turn
it to ON position (B) to display the “ID Key Setting” screen
on the machine monitor.

2. Replace the registration key within 10 seconds with the

normal key (black) to be registered and turn it to ON posi-
tion (B).

3. The ID No. of the normal key (black) currently inserted is

displayed on the machine monitor, and registration is com-
pleted.
When registering another normal key (black) at this time,
repeat the operation of step 2.

REMARK
You can register up to 255 normal keys (black) in the machine.
If normal keys are to the maximum, the screen in the figure is
displayed.

3-127
Explanation of Components Operation

REMARK
If you again register a normal key (black) which is registered al-
ready, the screen in the figure is displayed.

REMARK
If registration fails, the screen in the figure is displayed. If this
screen is displayed, repeat the registration procedure from the
first.

3-128
Operation Explanation of Components

Komatsu Closed Crankcase Ventilation (KCCV)

KCCV is a device to clean the gas discharged from the engine
crankcase with the filter element and return it to the engine air
intake system.
NOTICE
• The KCCV filter element needs to be replaced every
2000 hours.
• If the engine is operated without KCCV filter element
or if a filter element other than the Komatsu genuine
element is used, the engine sucks oil and foreign ma-
terial which can cause a failure. Always install Komat-
su genuine KCCV filter element.
• The filter element cannot be flushed. Never reuse the
filter element since it can cause a performance decre-
ment of engine, and it result in a failure even if it is
cleaned.

3-129
Explanation of Components Operation

Handle Urea SCR System

k WARNING
• Exhaust gas temperature may increase during regeneration and remain very hot after the end of re-
generation.
Do not come near the exhaust pipe outlet nor the aftertreatment devices.
Do not put any combustibles near the outlet of the exhaust pipe nor the aftertreatment devices.
• Disable the regeneration system while the machine operates in an environment containing flamma-
ble materials.

The Urea SCR system device sprays DEF into the exhaust gas to convert toxic nitrogen oxides (NOx) from ex-
haust gas into harmless nitrogen and water. DEF decomposes and hydrolyzes to produce ammonia (NH3),
which selectively reacts with nitrogen oxides to convert nitrogen and water.
The Komatsu Urea SCR System continuously monitors machine operation conditions and gathers information
on defective operations such as malfunctions. The information is used for system diagnostics and also for In-
ducement, required on engine systems that use Urea SCR systems. Inducement is intended for the operators to
take prompt procedures to maintain and correct inappropriate behaviors of Urea SCR systems. Alerts in Induce-
ment of the Komatsu Urea SCR System progress step by step. It starts with visual indications on the machine
monitor with audible sounds to engine power deration to avoid dangerous conditions.
The Komatsu Urea System also monitors recurrences of defective operations of the system. Inducement is acti-
vated when another defective operation occurs less than 40 hours after the first defect is repaired.
When the purification function of the Komatsu Urea System is deteriorated from the machine operating condi-
tions, regeneration may activate.
NOTICE
• Do not put anything other than DEF into the DEF tank. Foreign materials in DEF, such as dried urea
when you disconnect the hose and change the filter, may cause a malfunction of the equipment.
• Do not paint the DEF injector or pump. Cover the pump and injector whenever you paint around
them.
• Use only DEF which complies with the quality standards. If you add any additive agents, water, etc.
to DEF, the equipment will not operate correctly, and will not comply with the exhaust gas regula-
tions. It may also cause a failure in the engine system. If you supply a solution other than DEF, con-
tact Komatsu distributor.
To prevent deterioration of the aftertreatment devices, the ex-
haust gas temperature rises automatically, which is regenera-
tion. During regeneration, the aftertreatment devices regenara-
tion display (1) comes on in the indicator lamp.

When the engine is idled for long periods of time, regeneration

will occur more frequently. This is not an error in regeneration.
When regeneration performance caution lamp (2) comes on,
stop the machine in a safe area and start manual stationary re-
generation.
Depending on the urgency, two steps to request manual sta-
tionary regeneration are started.
When you press F6 on the main menu screen, the machine
monitor shows “Aftertreatment Devices Regeneration” screen
in the user menu.

3-130
Operation Explanation of Components

To stop the engine during regeneration, run the engine for more than 5 minutes at low idle.
When the Degree of Urgency is Low
• When caution lamp (2) comes on in yellow (action level
(3): “L01”, screen (A) is displayed first.
• The action level goes out after 2 seconds and the screen
changes to standard screen (B).
• When you set the parking brake lever and work equipment
lock lever to LOCK position or the joystick (steering, direc-
tional and gear shift lever) and blade control lever in NEU-
TRAL, the “Aftertreatment Devices Regeneration” screen
(C) will appear after 3 seconds. If you do not activate man-
ual stationary regeneration, normal screen(B) will appear
after 30 seconds.
The “Aftertreatment Devices Regeneration” screen (C) is
shown for 30 seconds every 2 hours until regeneration is
performed.
• When caution lamp (2) comes on in yellow, after the end of
ongoing work stops the machine in a safe area and acti-
vate manual stationary regeneration.

3-131
Explanation of Components Operation

When the Degree of Urgency is High

• When caution lamp (2) and action level: “L03” comes on in
red (3).
• When you set the parking brake lever and work equipment
lock lever to LOCK position or the joystick (steering, direc-
tional and gear shift lever) and blade control lever in NEU-
TRAL, “Aftertreatment Devices Regeneration” screen (C)
shows after 3 seconds. Then, the “Aftertreatment Devices
Regeneration” screen (C) and standard screen (D) alter-
nate automatically until manual stationary regeneration is
activated.
• When caution lamp (2) comes on in red, stop the machine
immediately in a safe area and activate the manual sta-
tionary regeneration.

3-132
Operation Explanation of Components

Manual Stationary Regeneration

When the manual stationary regeneration is required, check
whether the caution lamp (1) is lit.
During manual stationary regeneration, there are times when
engine low idle speed increases automatically.

1. Move the machine to a safe area and stop it with the en-
gine running.
2. Make sure there are no persons or combustible materials
around the exhaust pipe outlet and aftertreatment devices.
3. Operate the parking brake lever and work equipment lock
lever by holding the operating portions on the top to set the
levers in LOCK position (L).

4. Set the fuel control dial to the Low idle (MIN) position.

5. Push F6 to show the “Aftertreatment Devices Regenera-

tion” screen.
6. Select manual stationary regeneration, and push F6.

If the screen shown in the figure does not change after you
push F6 in Procedure 6, recheck procedures 1 through 5, and
then push switch F6 again.

3-133
Explanation of Components Operation

When manual stationary regeneration is not activated even af-

ter you push the switch F6, return to the normal screen. Then
push the switch F5, and follow the instructions shown on the
screen.
Manual stationary regeneration may continue for over 40 mi-
nutes. Do not operate any screen switches, fuel control dial, etc
before until regeneration is completed.

3-134
Operation Explanation of Components

Procedure to Set Aftertreatment Device Regeneration Disable

If necessary, it is possible to disable automatic regeneration. Also, it is possible to stop regeneration in progress.
When the Aftertreatment Devices Regeneration Must be Started
1. When the aftertreatment devices regeneration display is
not lighting on the standard screen, push F6 on the stand-
ard screen.

2. Use F1 and F2 to select the “Aftertreatment Devices Re-

generation” menu (C) and display the “Aftertreatment Devi-
ces Regeneration” screen.
3. With regeneration disable highlighted, push function switch
F6 to disable regeneration.

Even if regeneration is disabled, the aftertreatment device re-

generation display (1) may come on under certain condition. In
this case, it is impossible to disable regeneration.

3-135
Explanation of Components Operation

Procedures to Stop the Regeneration

1. When aftertreatment device regeneration display (1) is lit
on the standard screen, push F6 on the standard screen to
open the “Aftertreatment Devices Regeneration” screen.

2. With regeneration disable highlighted, push function switch

F6 to disable regeneration.
It may be impossible to disable regeneration during regenera-
tion.

3-136
Operation Explanation of Components

Procedure to Cancel Aftertreatment Device Regeneration Disable

k CAUTION
Before you start regeneration again, move the machine to a safe area first.

1. Set the parking brake lever and the work equipment lock lever to the lock position and the fuel control dial
to the low idle position.
2. Push F6 on the normal screen, to open the “Aftertreatment
Devices Regeneration” screen.
If this screen does not show, push F1 and F2 to toggle to
this screen.

3. Select Yes to cancel regeneration disable and push F6.

3-137
Explanation of Components Operation

Operation of Urea SCR System

The Urea SCR System automatically starts operating as soon as the engine is started.
Even after the engine starting switch key is turned to OFF position, the devices will still be in operation up to 7
minutes to purge any DEF in the lines, the injector and the supply pump back to the DEF tank. It does not indi-
cate any abnormality. When DEF has been returned to the tank, the devices stop.
Do not turn OFF the battery disconnect switch while the devices are still in operation. When the devices com-
plete their shutdown process, the system operating lamp will go out, and the battery disconnect switch may be
disconnected.

In Cold Weather
DEF freezes at –11 °C {12 °F} .
Urea SCR system is equipped with a heating system to thaw frozen DEF once it is frozen, for example, during
parking and to prevent DEF from freezing during operation.
In case DEF freezes during parking, once the engine starts running the heating system automatically starts pro-
viding heat to thaw frozen DEF. The pump and the injector start working only after a proper amount of DEF is
thawed. This may be noticed as a delay in the start of functioning of the pump and the injector.
The heating system is also activated automatically during operation to prevent DEF from freezing whenever the
ambient temperature drops below a certain threshold where DEF in the system may freeze. In the event that the
ambient temperature drops further than a temperature where the heating system is capable of maintaining fluidi-
ty of DEF, the DEF system automatically starts purging the remaining DEF back to the tank and stops pumping
and injection while heating continues. Once the ambient temperature rises above a temperature where DEF
system becomes functional, it resumes operation automatically.
Short duration of white plume given off from the tail pipe may be visible at and shortly after engine start-up in
cold weather, but this is not malfunction.

3-138
Operation Explanation of Components

Inducement Strategy When the DEF Tank Level Becomes Low

When the amount of DEF in the tank goes low, the Inducement strategy will be activated.
If Inducement starts, add DEF to the DEF tank immediately.
The DEF level caution lamp (1) on the monitor lights up, the audible alert starts, and the Action level is dis-
played, and Inducement strategy is activated. Inducement strategy includes engine output deration, speed limi-
tation, or other warning actions intend to prompt the operator to maintain or repair SCR system.
The Inducement strategy progressed in 5 levels from Warning, Escalated Warning, Mild inducement, Severe In-
ducement and Final Inducement.
The DEF level caution lamp (1) on the machine monitor will
light up, audible alert will start, then Action level will be dis-
played on the machine monitor, and engine power will be derat-
ed in steps.
In Action Level “L03 (Mild Inducement)” and “L04 (Severe In-
ducement and Final Inducement)” engine power will be derat-
ed. When Action Level “L03” or “L04” is displayed, move the
machine to a safe place and add DEF.
If operation is continued further without adding DEF at Severe
Inducement, engine speed will be fixed at low idle. (Final In-
ducement)
The content of the warning can be checked on the “SCR Information” screen of the user menu.
Perform the following procedure.
Press F6 on the standard screen to display the “SCR Informa-
tion” screen of the user menu.
If either the parking brake lever and work equipment lock lever
is set to LOCK position or the joystick (steering, directional and
gear shift lever) and blade control lever are in NEUTRAL posi-
tion for over 3 seconds, “SCR Information” screen of the user
menu will pop up automatically while the Urea SCR system is
in Inducement.

“SCR Information” screen displays the DEF level caution lamp

(1), the DEF level gauge (2), information on the Urea SCR Sys-
tem condition (3), and the current status of Inducement (4).
If Inducement starts, stop the machine in a safe place and add
DEF.
Once the audible alert starts, “The buzzer cancel switch” does
not work unless DEF is added.

• Warning:
2 gradations of the DEF level gauge light up in the red
range.
The DEF level caution lamp (1) lights up in red.
No audible alert.
No Action level is displayed.
Press F6 to display the “SCR Information” screen.

3-139
Explanation of Components Operation

Inducement status (4): “1 DEF low level warning appears.”

Add DEF to the DEF tank immediately.

• Escalated Warning:
The audible alert sounds in repetition of “three beeps and
a pause”.
2 gradations of the DEF level gauge light up in the red
range.
DEF level caution lamp (1) lights up in red.
No Action level is displayed.
Press F6 to display the “SCR Information” screen.

Inducement status (4): “2 Without treatment, engine power

will be derated.”
Add DEF to the DEF tank immediately.

• Mild Inducement:
The audible alert sounds in short and sharp beeps.
1 gradation of the DEF level gauge light up in red.
The DEF level caution lamp (1) lights up in red.
Action Level “L03” is displayed in red (5).
Press F6 to display the “SCR Information” screen.

Inducement status (4): “3 Engine power is under deration.”

Add DEF to the DEF tank immediately.

3-140
Operation Explanation of Components

• Severe Inducement:
The audible alert sounds in continuous beep.
No gradation of the DEF level gauge lights up.
The DEF level caution lamp (1) lights up in red.
The Action level “L04” is displayed in red (5).
Press F6 to display the “SCR Information” screen.
When all gradations of the DEF level gauge go off, DEF re-
filling amount is approximately 20 ℓ {5.28 U.S.Gal} to fill up
the DEF tank.

Inducement status (4): “4 Engine power is under heavy de-

ration.”
The remaining time (Hour and minute) to the Final Induce-
ment is displayed in the column (6) of the “SCR Informa-
tion” screen. If no DEF is added during the “Severe In-
ducement”, Inducement advances to “Final Inducement”
within 1 hour. At “Final Inducement”, engine speed is fixed
at low idle.

Engine power can be restored temporarily from power derate. This engine power restoration works only
when the Inducement status is “Severe Inducement” and relieves back temporarily to the power deration of
the “Mild Inducement”. The operator can restore engine power through the machine monitor. For the engine
power restoration procedure, refer to the section of “Temporary Restoration from Inducement” in this man-
ual. Once in “Severe Inducement” and it becomes necessary to restore engine power, use the engine pow-
er restoration function to move the machine to a safe place and add DEF.
• Final Inducement:
1 hour after “Severe Inducement” starts, advancing to “Fi-
nal Inducement”.
The audible alert sounds in continuous beep.
No gradation of the DEF level gauge light up.
The DEF level caution lamp (1) lights up in red.
Action level “L04” is displayed in red (5).
Press F6 to display the “SCR Information” screen.

Inducement status (4): “5 Engine is running at low idle.”

Engine speed is fixed at low idle to disable practical ma-
chine operation.
Add DEF to the DEF tank immediately.
In case the system does not come out of Inducement even
if DEF is added in the tank, contact your Komatsu Distribu-
tor.

3-141
Explanation of Components Operation

Inducement Strategy When Abnormality is Found in Urea SCR System Devices

If any abnormality is detected in the DEF quality or in the Urea SCR system, the Inducement strategy is activa-
ted.
The inducement strategy progresses in 5 levels, “Warning”,
“Escalated Warning”, “Mild Inducement”, “Severe Inducement”
and “Final Inducement”. The Inducement strategy includes vis-
ual alert by the DEF caution lamp (1), and Action Level dis-
played on the machine monitor (2), and the audible alert by a
buzzer and stepwise engine power deration that advances to
speed limitation to low idle. Engine power deration starts with
Action Level “L03 (Mild Inducement)” and advances to further
deration when “L04 (Severe Inducement and Final Induce-
ment)” is displayed. Once the system advances to “Final In-
ducement”, the engine speed is fixed to low idle. If “L03” is dis-
played, move the machine to a safe place and contact your Ko-
matsu distributor.
The content of the warning can be checked on the “SCR Information” screen of the user menu.
Perform the following procedure.
Press F6 on the standard screen to display the “SCR Informa-
tion” screen of the user menu.
If either the parking brake lever and work equipment lock lever
to LOCK position or the joystick (steering, directional and gear
shift lever) and blade control lever are in NEUTRAL position for
over 3 seconds, “SCR Information” screen of the user menu
will pop up automatically while the Urea SCR system is in In-
ducement.

“SCR Information” screen displays remaining time to the next

Inducement status in the column (5), and information on the
Urea SCR System condition (3), and the current status of In-
ducement (4).

• Warning:
No audible alert.
The DEF system caution lamp (1) lights up in yellow.
Note: Action Level “L01” once shows up in yellow on the
machine monitor (2) for 2 seconds and goes out.
Press F6 to display the “SCR Information” screen.

3-142
Operation Explanation of Components

“SCR Information” screen message (4): “1 Please inspect

and maintain SCR system.”
Move the machine to the safe place and contact your Ko-
matsu Distributor.
If operation continues for 1 hour after “Warning” started
without taking any actions instructed by the Action Level
table, Inducement advances to “Escalated Warning”.

• Escalated Warning:
The audible alert sounds in repetition of “three beeps and
a pause”.
The DEF system caution lamp (1) lights up in yellow.
If operation continues for 1 hour after “Warning” started
without taking any actions instructed by the Action Level
table, Inducement advances to “Escalated Warning”.
Press F6 to display the “SCR Information” screen.

“SCR Information” screen message (4): “2 Without treat-

ment, engine power will be derated.”
Move the machine to the safe place and contact your Ko-
matsu Distributor.
The duration of “Escalated Warning” is 1 hour. The remain-
ing time (Minutes) to “Mild Inducement” is displayed in the
column (5) of the “SCR Information” screen.
In “Mild Inducement”, engine performance will be derated.

• Mild Inducement:
The audible alert sounds in short and sharp beeps.
The DEF system caution lamp (1) lights up in red.
Action level “L03” lights up in red at action level display (2)
and stays on.
Press F6 to display the “SCR Information” screen.

“SCR Information” screen message (4): “3 Engine power is

under deration.”
Due to the engine power deration, capability of the ma-
chine will be limited.
Move the machine to the safe place and contact your Ko-
matsu Distributor.
The duration of “Mild Inducement” is 1 hour. The remaining
time (Minutes) to “Severe Inducement” is displayed in the
column (5) of the “SCR Information” screen.
In “Severe Inducement”, engine power will be derated fur-
ther.

3-143
Explanation of Components Operation

• Severe Inducement:
The audible alert sounds in continuous beep.
The DEF system caution lamp (1) lights up in red.
Action level “L04” lights up in red (2).
Press F6 to display the “SCR Information” screen.

“SCR Information” screen message (4): “4 Engine power is

under heavy deration.”
Due to the further deration of engine power, capability the
machine will be limited further.
Move the machine to the safe place and contact your Ko-
matsu Distributor.
The duration of “Severe Inducement” is 1 hour. The re-
maining time (Minutes) to “Final Inducement” is displayed
in the column (5) of the “SCR Information” screen.
In “Final Inducement”, engine speed will be fixed at low
idle.
Engine power can be restored temporarily from power derate. If Inducement advances to “Severe Induce-
ment” and it becomes necessary to restore engine power, use the engine power restoration function to
move the machine to a safe place and contact your Komatsu distributor. This engine power restoration
works only when the Inducement status is “Severe Inducement” and relieves back temporarily to the power
deration of “Mild Inducement”. The operator can restore engine power through the machine monitor. For the
engine power restoration procedure, refer to the section of “Temporary Restoration from Inducement” in this
manual.
• Final Inducement:
The audible alert sounds in continuous beep.
The DEF system caution lamp (1) lights up in red.
Action level “L04” lights up in red (2) and stays on.
Press F6 to display the “SCR Information” screen.

“SCR Information” screen message (4): “5 Engine is run-

ning at low idle.”
Engine speed is fixed at low idle to disable practical ma-
chine operation.
Move the machine to a safe place and contact your Ko-
matsu Distributor.

3-144
Operation Explanation of Components

Temporary Restoration from Inducement

Temporary Restoration from Inducement is one of the Inducement strategies allowed to be included in Urea
SCR systems.
In case the Urea SCR system advances to “Severe Inducement”, engine power is derated heavily. This may
cause difficulties of moving the machine to a safe place for adding DEF or troubleshooting and correcting abnor-
malities of the Urea SCR system. For temporary remedies from these difficulties the operator can restore engine
power for a short time to the deration of “Mild Inducement” through the machine monitor. Note that “Temporary
Restoration from Inducement” does not regain full engine power.
“Temporary Restoration from Inducement” can be activated only when the Urea SCR system is in “Severe In-
ducement”. The maximum duration is limited to 30 minutes in each restoration operation, and 3 operations are
allowed, but “Temporary Restoration from Inducement” is turned off whenever the system advances to “Final In-
ducement” even if either 30 minutes or 3 operations are not used up.
All the abnormalities of the Urea SCR system need to be corrected to regain another restoration capability.
If all the abnormalities of the Urea SCR system are not corrected when the system is in “Severe Inducement”,
the system advances to “Final Inducement” in 1 hour after “Severe Inducement” started and engine speed will
be fixed to low idle to disable practical machine operation. If the system advances to “Severe Inducement”, uti-
lize “Temporary Restoration from Inducement” immediately.
Procedure to activate “Temporary Restoration from Inducement”.
1. Press F6 to display the “SCR Information” screen when
the Standard screen is on, only when the Urea SCR sys-
tem is in “Severe Inducement”.

2. Press F6 to display the menu windows popping up in the

bottom half of the “SCR Information”.
The menu windows popping up in the bottom half of the
“SCR Information” screen alternate every 15 seconds as
shown in the graphics A and B.

3-145
Explanation of Components Operation

3. Press F6 while the pop-up menu screen B is displayed.

The “Engine power Recovery” window will be displayed.
If F6 is not pressed for 30 seconds, “ Standard Screen” will
be displayed, and start again by pressing F6.
The remaining number of operations of Temporary Resto-
ration from inducement is displayed in the column (1) of
the pop-up menu window B.

4. Press F6 while the “Engine power Recovery” window is

displayed.
Temporary Restoration from Inducement is activated and
engine power deration is relieved to the deration of “Mild
Inducement” for the maximum of 30 minutes as long as
there is sufficient remaining time to “Final Inducement”.
Note that whenever Inducement advances to “Final In-
ducement” Temporary Restoration from Inducement will be
turned off.

The remaining time (minutes/seconds) of “Temporary Re-

storation from Inducement” is displayed in the column (2)
on the “SCR Information” screen.

If it is decided NOT to activate “Temporary Restoration from Inducement” after having progressed to the “Engine
Power Recovery” window, follow the steps explained in this section.
To deactivate “Temporary Restoration from Inducement” function.

3-146
Operation Explanation of Components

1. Press F5 while the “Engine Power Recovery” window is

displayed.
This procedure is split from procedure 4 in “Temporary Re-
storation from Inducement”.

“SCR Information” screen is displayed.

2. Move any operating lever to display “Standard Screen” is

displayed.
“Temporary Restoration from Inducement” is deactivated.

Inducement Strategy for Abnormalities Recurrences in 40 Hours

The Urea SCR system continuously monitors its operation conditions and stores information on inappropriate
operations including malfunctions. The stored information is utilized to monitor recurrences of abnormalities,
“Abnormality Recurrence Counter”. “Abnormality Recurrence Counter” is required by the U.S. Environmental
Protection Agency. The recurrence monitoring spans 40 hours and it monitors the abnormalities that trigger In-
ducement other than the amount of DEF in the tank.
If another abnormality/abnormalities is detected within 40 hours after the previous abnormalities were corrected,
regardless of the level of the previous Inducement and whether the new abnormality/abnormalities is the same
as the previous ones or not, it is judged as a recurrence.
If a recurrence occurs, “Severe Inducement” will be activated. If this occurs, utilize “Temporary Restoration from
Inducement” and move the machine to a safe place, and contact your Komatsu distributor.
The duration of “Severe Inducement” in the recurrence is limited to 30 minutes. If the abnormalities are not cor-
rected while Inducement is in “Severe Inducement (30 minutes)”, Inducement will advance to “Final Inducement”
and engine speed will be fixed to low idle to disable practical machine operation.
Note that although maximum duration of the power restoration is 30 minutes and 3 operations are possible,
whenever Inducement advances to “Final Inducement”, “Temporary Restoration from Inducement” will be turned
off and its function will be held off till all the abnormalities are corrected.
To activate “Temporary Restoration from Inducement”, refer to the “Temporary Restoration from Inducement”
section in this manual.

3-147
Explanation of Components Operation

DEF Filter
DEF filter is an filter element to clean DEF sucked from the
DEF tank by DEF pump, and to supply it to DEF injector.
NOTICE
• The DEF filter element needs to be replaced every
2000 hours.
• If the machine is operated without DEF filter attached,
or with the filter other than Komatsu genuine parts,
foreign materials may enter into DEF pump and DEF
injector which will cause failure of the machine. Never
operate the machine without DEF filter attached, nor
use the filter other than Komatsu genuine parts.
• DEF filter cannot be flushed. Flushing or regenerating
of it will degrade the performance of DEF filter, and will
contaminate DEF pump and DEF injector which will
cause the failure of the machine. Never reuse the DEF
filter.

3-148
Operation Explanation of Components

KOMTRAX
k WARNING
• Never disassemble, repair, modify, or move the wireless communication terminal, antenna, or ca-
bles. This may cause failure or fire on the wireless equipment or the machine itself.
• Near the blasting jobsite, there may be a danger of unexpected explosion due to use of the wireless
equipment and resulting serious personal injury or death.
If you have to operate the machine within 12 m {within 39 ft 4 in} from the remote-controlled blasting
device, the power supply cable of the wireless communication device must be disconnected in ad-
vance.

KOMTRAX is a vehicle management system that remotely manages the machines equipped with the KOM-
TRAX device by using satellite communication or portable radio communication.
The GPS (Global Positioning System), receiver, and communication system are equipped in the vehicle man-
agement system.
The machine information such as the machine maintenance, maintenance management, operating situation
management, and machine location management is gathered from the inside network of the machine. It can be
useful for you to perform the machine management by yourself. Your Komatsu distributor uses the above ma-
chine information for supply of service to the customers, improvement of our products and service, etc.
The type of information which is sent from the machine may vary depending on the machine. For the radio sta-
tion establishment of KOMTRAX, consult your Komatsu distributor.

Power Supply for KOMTRAX

• Even when the key in the starting switch of the KOMTRAX system is at OFF position, a small amount of
electric power is consumed.
It is recommended to run the engine periodically to charge the battery.
• When using the battery disconnect switch, turn the starting switch to OFF position and, after checking that
the system operating lamp is not lit, set the battery disconnect switch key to OFF position and pull it out.
When the battery disconnect switch is turned to OFF position, it is possible to prevent power consumption
of the battery, but the functions of KOMTRAX stop at the same time.
• If the power supply cable of KOMTRAX system device has to be disconnected, contact your Komatsu dis-
tributor.

3-149
Machine Operations and Controls Operation

Machine Operations and Controls

Checks and Adjustment Before You Start Engine
How to Do Walk-Around Check
Before starting the engine, walk around the machine and look at the underside of chassis for anything unusual
like loose bolts and nuts, leakage of fuel, oil and coolant. Also check the condition of the work equipment and
the hydraulic system.
Check also for loose wiring, play, and accumulation of dust in places that get very hot and are exposed to ex-
tremely high temperatures.

k WARNING
• Any combustible materials accumulated around the exhaust pipe, aftertreatment devices, turbo-
charger, or other high temperature engine parts or the battery, and leakage of fuel or oil will cause
the machine to catch fire.
Check carefully, and if any abnormality is found, repair it or contact your Komatsu distributor.
• Do not get on or off the machine from the rear. Since the floor is slippery and not seen from the
operator seat, it is dangerous to get on or off there. Always use the handrail and step at the side
when getting on or off the machine.

If the machine is inclining, make it level before checking.

Always perform the following inspections and cleaning every day before starting engine for the day's work.
1. Check for damage, wear, play in work equipment, cylinders, linkage, and hoses.
Check for cracks, excessive wear, play in work equipment, cylinders, linkage, and hoses. If any problem is
found, repair it.
2. Remove dirt from around the engine and radiator.
Check for dirt accumulated around the engine and radiator. Also check for flammable materials (dry leaves,
twigs, etc.) around the exhaust pipe, aftertreatment devices, turbocharger, or other high temperature engine
parts. If dirt or flammable materials are found, remove them.
3. Check around the engine for leakage of coolant, oil, and air.
Check for oil leakage from the engine, coolant leakage from the cooling system, and air leakage from the
air intake system. If any problem is found, repair it.
4. Make sure that there is no dirt, especially electrolyte such as snow melting agent or salt on the battery, and
no deposits around the battery.
Do the cleaning around the battery. For how to handle the battery such as cleaning precautions, see “Han-
dle Battery”. Also, do not use a direct air blow or dry cloth to clean the battery. A wet cloth will prevent fire or
explosion from static electricity.
5. Check the fuel line for leakage.
Check for leakage of fuel or damage to the hoses and tubes. If any problem is found, repair it.
6. Clean DEF line and check it for leakage.
Check around DEF tank for dirt, and clean the blue DEF filler cap and the area around. Check DEF tank,
pump, injector, hoses, and joints for leakage. If any problem is found, ask your Komatsu distributor for re-
pair.
7. Check the lower part of chassis, final drive case, hydraulic tank, hoses, and joints for oil leakage.
Check for oil leakage. If any problem is found, repair the place where the oil is leaking.
Check for oil leakage from the undercover. Check the ground for traces of oil leakage.
8. Check the undercarriage (track, sprocket, idler, guard) for damage, wear, loose bolts, or leakage of oil from
rollers.
If any problem is found, repair it.

3-150
Operation Machine Operations and Controls

9. Check the handrails and steps for problems and check the bolts for looseness.
If any problem is found, repair it. Tighten any loose bolts.
10. Check the gauges and monitor for problem.
Check for problem in the gauges and monitor in the operator's cab. If any problem is found, replace the
part. Clean off any dirt on the surface.
REMARK
When cleaning the stains deposited on the monitor surface such as dusts, brush them off with a clean, soft
and dry cloth.
For sticky dirt such as oil, remove it with glass cleaner for family use on the market (weakly acid to weakly
alkaline, containing no abrasive), and then finish-wipe with a clean, soft, and dry cloth.
11. Check the panels, gauges, and lamps for breakage, and check the bolt for loosening.
Check the panels, gauges, and lamps for abnormality, and replace the failed parts, if any. Clean off any dirt
on the surface.
12. Check the seat belt and mounting hardware.
Check the seat belt and mounting hardware for any abnormality. If any damage is found, ask your Komatsu
distributor to replace it with new one.
13. Check and clean the camera.
When cleaning the camera, wipe off any dirt with soft cloth.
When cleaning camera, if you stand on an unstable place, or take an unstable posture, you may fall and be
injured. Put proper stepladder or step on the level and firm ground, and clean the camera in secure posture.
Check the camera for any abnormality. If any problem is found, ask your Komatsu distributor for repair.
14. Remove dirt from around the aftertreatment devices.
Check the space around the aftertreatment devices for accumulated dirt and combustible materials (dry
leaves and twigs). If any dirt or combustible materials are found, remove them.
15. Check around the aftertreatment devices for exhaust gas leakage.
Check the pipe connecting the turbocharger to the aftertreatment devices for leakage of exhaust gas. If any
problem is found, ask your Komatsu distributor for repair.
16. Check around SCR for exhaust gas leakage.
Check the SCR connections and the pipe for leakage of exhaust gas (and urea deposit). If any problem is
found, ask your Komatsu distributor for repair.
17. Check KCCV piping for oil leakage.
Check the pipes (3 pieces) which are connecting the KCCV filter to the turbocharger, oil pan, and cylinder
head for ooze of oil. If any problem is found, ask your Komatsu distributor for repair.

3-151
Machine Operations and Controls Operation

How to Examine Before You Start Operation

Always check the items in this section before starting the engine each day.

How to Drain Water and Sediment from Fuel Tank

Perform this procedure before operating the machine.
Prepare a container to catch drained fuel.
1. Open the fuel tank inspection cover on the right side of the
machine.
2. Pass the hose through the hole at the bottom of the tank.
3. Prepare a container to catch the drained fuel.
4. Turn lower drain valve (1) in the cover to OPEN position
(O).
The sediment and water accumulated in the bottom are
drained together.
Be careful not to get fuel on yourself.
5. When clean fuel flows out, turn drain valve (1) to CLOSE
position (C).

3-152
Operation Machine Operations and Controls

How to Examine Water Separator, Drain Water and Sediment

The water separator serves to separate water mixed in the fuel.
Prepare a container to catch the water and sediment.
1. Open the fuel tank inspection cover on the right side of the
machine.
The water separator is integrated with fuel prefilter (1) and
located in the lower part.
2. Check the water level and sediment through transparent
cup (2).
NOTICE
If the water in transparent cup (2) freezes, wait until
the frozen water has melted completely, then follow
the procedure to drain the water.
3. If water and sediment are accumulated, drain the water and remove the sediment.
1) Pass the drain hose (3) through the hole of the tank
bottom plate.
2) Prepare a container to catch the water and sediment
at the end of the drain hose (3).

3) Loosen the drain valve (4) and drain the water.

4) When fuel starts draining from the drain hose (3),
tighten the drain valve (4) immediately.

5) Return the drain hose (3) to its original position.

REMARK
• If the transparent cup (2) is so dirty that the inside
cannot be seen, clean it when replacing the filter.
• If the drain valve (4) has been removed during the
cleaning operation, coat the O-ring (5) with
grease and tighten it by hand until it contacts the
bottom.
• When applying to the valve, be careful not to al-
low the grease to adhere to the drain port (6) and
the threaded portion (7) of the drain valve.
4. Close the fuel tank inspection cover.

3-153
Machine Operations and Controls Operation

How to Examine Oil Level in Hydraulic Tank, Add Oil

k WARNING
• Immediately after the engine is stopped, its parts and oil are still very hot and may cause burn in-
jury. Wait for the temperature to go down, and then start the work.
• When the oil filler cap is removed, oil may spout out. After stopping the engine, wait for the oil tem-
perature to go down, turn the cap slowly to release the internal pressure, then remove the cap with
care.

NOTICE
Do not add oil above H line. It may damage the oil circuit and cause the oil to spurt out.
Set the work equipment to the posture shown in the figure be-
fore checking hydraulic oil level or adding oil.

1. Place the machine on a level ground and lower the work equipment to the ground.
If the machine is inclining, make it level.
2. Stop the engine.
3. Wait for approximately 5 minutes, and then open the hydraulic tank inspection cover at the rear left of the
machine.
4. Check the oil level with sight gauge (G).

3-154
Operation Machine Operations and Controls

• When the oil level is between H and L marks on sight

gauge (G)
The oil level is proper. Close the hydraulic tank in-
spection cover.
• When the oil level is below L mark
The oil is insufficient. Add hydraulic oil through oil filler
port (F) on top of the hydraulic tank.
REMARK
The oil level changes depending on the oil tempera-
ture. Use the following as guide line.
Before starting operation: Between H and L marks (oil
temperature 10 to 30 °C {50 to 86 °F} )
During normal operation: Around H mark (oil tempera-
ture 50 to 80 °C {122 to 176 °F} )
After adding oil, close the cap securely and always
lock with key.

3-155
Machine Operations and Controls Operation

How to Examine Coolant Level, Add Coolant

k WARNING
• Do not open the radiator cap unless necessary. When checking the coolant level, check the reser-
voir tank when the engine is cold.
• Do not remove the reservoir tank cap while the radiator coolant temperature is high. Boiling coolant
may spurt out. After the coolant temperature goes down, turn the cap slowly to release the pres-
sure, then remove it.

1. Open the hydraulic tank inspection cover on the left side of the machine.
2. Check that the coolant level is between FULL and LOW
marks of reservoir tank (1).
• When the coolant level is between FULL and LOW
marks
The coolant level is proper.
• When the coolant level is below LOW mark
The coolant is insufficient. Add coolant to FULL level
through the filler port of reservoir tank (1).
REMARK
The coolant may overflow from the reservoir tank
drain hose. This is no problem. It occurs because too
much coolant has been added.
After adding, tighten the cap securely.
3. Check reservoir tank (1) for abnormality.
If reservoir tank (1) is empty, leakage of coolant should be
suspected.
4. If reservoir tank (1) has abnormality, repair it immediately.
5. Check the coolant level in the radiator.
6. If the coolant level is low, add Non-Amine Engine Coolant
(AF-NAC) of the same density in radiator according to the
Non-Amine Engine Coolant (AF-NAC) density table in “METHOD FOR USING FUEL, COOLANT AND LU-
BRICANTS ACCORDING TO AMBIENT TEMPERATURE” then add Non-Amine Engine Coolant (AF-NAC)
to the reservoir tank (1).
7. After adding, close the hydraulic tank inspection cover.
NOTICE
Before the engine is started (coolant temperature is low), if
the state that the coolant level in the reservoir tank is
clearly above the FULL level continues, refilling and drain-
ing function of the radiator cap (2) can be faulty. See “How
to Replace Radiator Cap”, and replace the radiator cap (2).

3-156
Operation Machine Operations and Controls

How to Examine Oil Level in Engine Oil Pan, Add Oil

k WARNING
Immediately after the engine is stopped, its parts and oil are still very hot, and may cause burn injury.
Wait for the temperature to go down, and then start the work.

Check the oil level either before engine starts or at least 15 minutes after the engine stops.
If the machine is inclining, make it level before checking the oil level.
When the ambient temperature is low, water or emulsified matter may stick to the dipstick, oil filler cap, etc. or
the drained oil may be milky white because of water vapor in the blowby gas. However, if the coolant level is
normal, it is not a problem.
Prepare a container to catch the drained oil.
1. Open the engine side covers (1) and (2) on the left side of
the machine.

2. Open the cap of oil filler port (F).

3. Pull out the dipstick (G) and wipe off the oil with a cloth.
4. Insert the dipstick (G) fully into the dipstick pipe and pull it
out.

5. Check if the oil is sticking up to between marks H and L on

dipstick (G).
• When the oil level is between marks H and L
The oil level is proper.
• When the oil level is below the mark L
The oil is insufficient. Add oil through the oil filler port
(F).
• When the oil level is above mark H
The oil is excessive. Adjust the oil to a proper level ac-
cording to the following procedure.

3-157
Machine Operations and Controls Operation

1) Remove the cover (3).

2) Pull out the hose (4).

3) Loosen the drain plug (P) to drain the excessive oil.
When draining the oil, put a container to catch the oil
under hose (4).
4) Check the oil level again.
6. After the oil is adjusted to a proper level, insert the dipstick
(G) fully into the dipstick pipe again.
7. Tighten the cap of oil filler port (F) securely.
8. Install the cover (3).
9. Close the engine side covers (1) and (2).

3-158
Operation Machine Operations and Controls

How to Examine Dust Indicator

1. Open the engine side cover on the left side of the machine.
2. Check if the inside yellow piston of dust indicator (1) is lap-
ped over the peripheral red zone.
3. If the yellow piston is lapped over the red zone, clean or
replace the element immediately.
For the cleaning method of the element, see “How to Ex-
amine, Clean and Replace Air Cleaner”.
REMARK
Also, clean or replace the air cleaner element when the air
cleaner clogging caution lamp lights up.
4. After checking, cleaning, and replacing, push the button of
dust indicator (1).
The yellow piston returns.
5. Close the engine side cover.

How to Examine Electric Wiring

k CAUTION
• If fuses are frequently blown or if there are traces of short-circuiting on the electrical wiring,
promptly ask your Komatsu distributor to locate the cause of it and to perform the repair.
• Keep the top surface of the battery clean and check the vent hole in the battery cap. If it is clogged
with dirt or dust, wash the battery cap with water to clear the vent hole.

NOTICE
In particular, inspect the wiring of “battery”, “starting motor”, and “alternator” with care.
Perform the following inspection.
• Perform inspection to confirm that the fuses have no defect and their capacity is proper.
• Perform inspection to confirm that there is no disconnection or trace of short-circuiting in the electric wiring
and no damage to the coating.
• Perform inspection to confirm that there is no loose terminals, and tighten any loose parts if found.
• Always check if there is any accumulation of combustible material around the battery, and remove such
combustible material.

3-159
Machine Operations and Controls Operation

How to Examine Fuel Level, Add Fuel

k WARNING
When adding fuel, never spill the fuel or let it overflow. This may cause fire.
If any fuel has spilled, wipe it up completely. If fuel has spilled over soil or sand, remove that soil or
sand.
Fuel is highly flammable and dangerous. Do not bring any open flame close.

When performing operations on slopes, to prevent the engine from sucking in air, pay careful attention to the
amount of fuel remaining in the tank.
1. Turn the starting switch to ON position (B).

2. Check the remaining level by the fuel gauge on the ma-

chine monitor.

• When the pointer is in green range (a) to (c)

The fuel level is proper.
• When the pointer is in red range (a) to (b)
The fuel is insufficient. Turn the starting switch back to
OFF position (A), and add fuel through fuel filler port
(F).
Fuel tank capacity: 273 ℓ {72.1 U.S.Gal}
After adding, tighten the cap securely.
3. After checking, turn the starting switch back to OFF posi-
tion (A).

3-160
Operation Machine Operations and Controls

How to Examine DEF Level and Add DEF

k WARNING
• Do not put any fluid other than DEF into DEF tank. In particular, if diesel fuel or gasoline is added
into the tank, it can cause a fire. Some fluids or agents added can create and emit a toxic gas.
• When opening the cap of DEF tank of the machine, the ammonia vapor may escape. Keep your face
away from the filler port during opening or refilling.
• Foreign material in DEF can shorten the service life of DEF injector and DEF pump. Before removing
the filler port cap, wipe off the dirt from around the filler port. Before inserting the filler nozzle into
the filler port, wipe off dirt from it.
• If DEF is spilled, immediately wash and clean the area with water. If spilled DEF is left unattended
and the area is not washed and cleaned, it can cause corrosion to the contaminated area and emit
toxic gas.

NOTICE
• Do not add the DEF more than the line F of the sight gauge (3). DEF may leak through the breather.
When the ambient temperature is low, if DEF freezes, it expands and may leak or break devices.
When DEF may freeze, do not add it more than line (7) of sight gauge (3).
Be careful of the DEF line when performing operations on a slope or traveling on a rough ground.
When the remaining DEF level is low, DEF pump may suck the air, or the warning may appear due to
the sudden drop of DEF level, or inducement may be actuated.
• If DEF is stored in another container, foreign material may be mixed in it and toxic gas or corrosive
substance may be produced by chemical reactions. When adding DEF, do not transfer it to another
container.
• If you use a funnel to add DEF, the strainer which is set at the filler port may be broken. Do not use a
funnel.
• When using a portable refill container, use it up each time. If any of it is left, completely seal it up.
Remove foreign material, if there is any.
• Do not wash the supply nozzle in city water. Minerals may clog the devices.
• Do not dilute DEF with water.
• If you add fluid other than DEF (diesel fuel, low concentration DEF, etc.) by mistake, the caution
lamp lights up and the alarm buzzer sounds to warn the abnormality. In this case, ask your Komatsu
distributor for draining of the wrong fluid and inspection. DEF injector and/or DEF pump may need
to be replaced.
1. Turn the starting switch to ON position (B).

3-161
Machine Operations and Controls Operation

2. Check the DEF level gauge on the machine monitor.

3. After checking, turn the starting switch back to OFF posi-

tion (A).
4. Check that the engine is stopped.
5. If DEF is insufficient, add it.

1) Open the DEF tank filler port cover (1).

For opening and closing of the cover, see “How to
Open and Close DEF Tank Filler Port Cover”.

2) Turn the DEF tank filler port cap (2) counterclockwise

(O) and open it.
Direction of (O): Open
Direction of (C): Close

3) While watching the sight gauge (3), add the DEF

through the filler port (2) until float (4) reaches the line
F (5).
Line (6) in the sight gauge indicates approximately 5 ℓ
{1.32 U.S.Gal} below the line F, and the line (7) indi-
cates approximately 10 ℓ {2.64 U.S.Gal} below the line
F.
The line (7) is the adding line when DEF may freeze in
cold weather.

4) Close the DEF tank filler port cap (2) by turning it clockwise (C).

3-162
Operation Machine Operations and Controls

Align the claw (8) of the cap with groove (9) of the filler
port and close the cap securely by turning it clockwise
by 90 °.

REMARK
• It is recommended to use a nozzle having a diameter and a length specified by ISO 22241-4 and an auto
stop function to add DEF. When the specified nozzle is used, the magnet installed inside the filler port of the
tank cancels the wrong fluid addition prevention device, and you can add DEF. This mechanism prevents
addition of DEF into the fuel tank, addition of fuel into DEF tank, and spill of DEF from the filler port.
• When using a nozzle which is not conformed to ISO 22241-4, hold it in your hand and add DEF carefully
while checking the sight gauge.
• The nozzle which does not comply with ISO 22241-4 feeds the DEF faster than the nozzle which conforms
to it. Accordingly, the DEF may overflow.
• The filter installed at filler port may be clogged if the DEF frequently overflows during refilling of the DEF.
Ask your Komatsu distributor for replacement of the DEF tank filler port filter.
• If it is difficult to see the sight gauge due to dirt, etc., re-
move the mounting bolts (B) (5 pieces), remove the cover
(A), and wipe off dirt on the surface of the sight gauge.

3-163
Machine Operations and Controls Operation

How to Add DEF from BIB Container

k CAUTION
• When opening or closing the DEF tank filler port cover, place the machine on a level ground, lower
the work equipment to the ground, stop the engine, and then perform the operation.
• When opening the DEF tank filler port cover, do not release the cover until the cover opens to be
horizontal.
• Do not put anything other than the BIB container on the opened DEF tank filler port cover.
• Do not put the BIB container on the opened DEF tank filler port cover if it is larger than 10 ℓ {approx-
imately 2.5 U.S.Gal} .
• Do not put the BIB container to the place other than specified.
• Do not put your foot and hand on or lean on the opened DEF tank filler port cover.
• Weight of the BIB container (10 ℓ {approximately 2.5 U.S.Gal} ) is 11 kg {24.255 lb} .
Before putting the BIB container on the DEF tank filler port cover, put it on the track first. Then,
climb on the top of the track from the front of the machine, and move the BIB container to the top of
the DEF tank filler port cover.

Prepare a BIB container (10 ℓ {approximately 2.5 U.S.Gal} ).

1. Place the machine on a level ground and lower the work equipment to the ground.
If the machine is inclining, make it level.
2. Stop the engine.
3. Put the BIB container on the track first.
4. Climb on the top of the track from the front of the machine.

5. Open the DEF tank filler port cover (1).

For opening and closing of the cover, “METHOD FOR
OPENING AND CLOSING DEF TANK FILLER PORT
COVER”.

3-164
Operation Machine Operations and Controls

6. Check the positions of (a) to (d) shown in the figure.

7. Put the BIB container gently on it.

8. Turn the DEF tank filler port cap (2) counterclockwise (O)
and open it.
Direction of (O): Open
Direction of (C): Close

9. Insert the bellows hose of the BIB container into the filler
port (2).
If it is difficult to insert the bellows hose into filler port (2),
make the end of the BIB container and (a) and (b) as ful-
crum, and lift up the other end of BIB container to perform
the work.

3-165
Machine Operations and Controls Operation

10. While watching the sight gauge (3), add the DEF through
the filler port (2) until float (4) reaches the line F (5).
Line (6) in the sight gauge indicates that it is approximately
5 ℓ {1.32 U.S.Gal} below the line F, and the line (7) indi-
cates that it is approximately 10 ℓ {2.64 U.S.Gal} below the
line F.
The line (7) is the adding line when DEF may freeze in
cold weather.

11. Close the DEF tank filler port cap (2) by turning it clockwise (C).
Align the claw (8) of the cap with groove (9) of the filler
port and close the cap securely by turning it clockwise by
90 °.

3-166
Operation Machine Operations and Controls

How to Examine Operation of Lamps

1. Turn the starting switch to ON position (B).

2. Set the headlamp switch to night mode (a) and daytime

mode (b), and check that the head lamp lights up in both
mode.

3. Turn the rear lamp switch to ON position (d), and check

that the rear lamp lights up.
If the lamps do not light up, a broken bulb or disconnected
wire are the possible causes. Ask your Komatsu distributor
for repairs.
4. After finishing the check, turn the head lamp to OFF posi-
tion (c) and turn the rear lamp to OFF position (e).

5. Turn the starting switch to OFF position (A).

3-167
Machine Operations and Controls Operation

How to Examine Machine Monitor

NOTICE
Do not perform the check before starting only on the monitor. Always perform other checks before start-
ing.
1. Turn starting switch (1) to ON position (B).
2. Check that KOMATSU mark is displayed first and then the
camera screen and the basic monitor screen is displayed
in order, and the buzzer sounds for approximately 2 sec-
onds.

If they do not light up, the machine monitor may be defective or may have an open circuit. Ask your Komatsu
distributor for the inspection.

How to Remove Sediment in Engine Room

Check that there is no deposit inside the engine compartment, particularly around the turbocharger, exhaust
manifold, and aftertreatment devices.
If there is any deposit, remove it.

3-168
Operation Machine Operations and Controls

How to Examine Operation State of Horn

1. Turn the starting switch to ON position (B).

2. Check that the horn sounds when the horn switch is press-
ed.
If the horn does not sound or its volume is extremely low, it
may be broken or may have an open circuit. Ask you Ko-
matsu distributor for repair.

3. Return the starting switch back to OFF position (A).

3-169
Machine Operations and Controls Operation

How to Examine Operation State of Backup Alarm

1. Turn the starting switch to ON position (B).

2. Operate the parking brake lever by holding the operating

portion on the top, and place the lever in LOCK position (L)

3. Set the joystick (steering, directional and gear shift lever)

in REVERSE position (R).
The alarm must sound immediately at this time.
The alarm keeps sounding until the joystick (steering, di-
rectional and gear shift lever) is set to NEUTRAL position
(N) or FORWARD position (F).
4. After checking the alarm operation, return the joystick
(steering, directional and gear shift lever) to NEUTRAL po-
sition (N) immediately.

5. Return the starting switch back to OFF position (A).

3-170
Operation Machine Operations and Controls

How to Examine Decelerator/Brake Pedal Stroke

k WARNING
If the brake pedal stroke is not between 50 to 60 mm {2 to 2.4 in} (below 50 mm {2 in} or over 60 mm
{2.4 in} ), the brake and steering force is too strong or insufficient. If the stroke is 60 mm {2.4 in} or
more, adjust it.

1. Depress the decelerator/brake pedal fully.

2. Check that the distance of stroke (A) at the center of the
pedal is 50 to 60 mm {2 to 2.4 in} .
When it exceeds 60 mm {2.4 in} or the brake force is in-
sufficient, ask your Komatsu distributor for adjustment.

3-171
Machine Operations and Controls Operation

Adjustment
Adjust Operator's Seat
k WARNING
• When adjusting the position of the operator's seat, always set the work equipment lock lever and
parking brake lever to LOCK positions to prevent any accidental contact with the control levers.
• When adjusting the operator's seat, stop the machine at a safe place.

NOTICE
If you adjust the operator's seat while parts, tools, empty cans, etc. are left around, the peripheral parts
and operator's seat may be damaged.
Before adjusting the operator's seat, check that there is no part, etc. around it.
• Always adjust the operator's seat before starting each operation or when the operators change shift.
• When adjusting the seat, put your back against the backrest and adjust to a position where the decelerator/
brake pedal can be fully depressed.

Air Suspension Seat (Low-Back Seat)

Adjust Seat Fore-and-Aft Direction
1. Pull up the fore-aft adjustment lever, and set the seat to
the desired position.
Fore-and-aft adjustment range: 180 mm {7.1 in} (18 steps)
2. After adjusting, release the lever.

How to Recline Seat

The reclining of the seat becomes large when the seat is moved forward, and it becomes smaller as the seat is
moved backward. When moving the seat backward, return the reclined seat back to the original position.
1. Pull up the reclining adjustment lever and set the seat
back to a position which is comfortable for operation.
Foremost reclining: Approx. 66 ° (Approx. 1.9 ° x 35 steps)
Rearmost reclining: Approx. 72 ° (Approx. 1.9 ° x 38 steps)
Sit with your back against the backrest when adjusting. If
your back is not touching the backrest, it may suddenly
move forward.
2. After adjusting, release the lever.

3-172
Operation Machine Operations and Controls

How to Tilt Seat

1. Pull up the tilt adjustment lever and adjust the front angle of the seat.
• To raise the front of the seat, apply your weight to the
rear of the seat, while pulling up lever.
• To lower the front of the seat, apply your weight to the
front of the seat, while pulling up lever.
Tilt adjustment: Up 5 °, down 5 °
2. After adjusting, release the lever.

Adjust Weight and Height of Seat

When adjusting the cushion and height of the seat, turn the starting switch to ON position since the air compres-
sor built in the seat is used for the adjustment.
NOTICE
Avoid using lever (1) continuously for 1 minute or longer since such practice can damage the air com-
pressor.
The seat height is adjusted pneumatically and in stepless.
1. Pull up lever (1) fully or push it down fully to adjust the seat
height.
For adjusting the seat height, pull up lever (1) to make the
seat higher and push it down to make the seat lower.
Adjust it so that the weight adjustment indicator (2) enters
the green range.
You can adjust the height by operating lever (1) in the
green range.
Vertical adjustment range: 75 mm {3 in}
Weight adjustment range: 60 to 150 kg {132 to 330 lb}
The suspension should be adjusted in proportion to the operator's weight to protect the operator. Operate
the lever in the normal operating posture to ensure the correct weight-based adjustment at this time.
2. After adjusting to the desired position, release lever (1).

3-173
Machine Operations and Controls Operation

Adjust Lumbar Support

Turn the adjustment knob to the right or left, and give proper
tension to the waist part.
The back cushion tension is increased by turning the adjust-
ment knob to the right.
The tension of the back cushion can be adjusted to 5 steps. If
the adjustment knob is turned to right further after the 5th step,
the tension returns to the 1st step.

How to Heat the Seat

k CAUTION
• Do not use it in the following cases to prevent low temperature burn or excessive cooling.
• When a person's ability to perceive the temperature is decreased
• When a person's ability to feel pain is decreased
• When a person has a delicate skin
• Do not put a heavy object on the seat cushion. Do not stick the seat cushion with needles or nails.
• When you use it, do not put objects which retain heat such as blankets or floor cushions on the
seat. The seat heater will overheat and it can cause burn injury or failure.
• Do not use it while the seat is wet. If water or beverage is spilled, immediately wipe it off with a dry
cloth and dry it well. Do not use the seat heater to dry the seat.

Turn on the seat heater switch.

(a): OFF position
(b): ON position
The backrest and seat surface are heated.

When the seat heater switch is turned on, the heater in the seat operates. When the seat surface temperature
exceeds approximately 20 °C {68 °F} , the heater is turned off automatically. When the temperature decreases
below approximately 10 °C {50 °F} , the heater is turned on automatically.
REMARK
When the seat surface temperature is above approximately 20 °C {68 °F} , the heater does not operate even if
the switch is turned on.

3-174
Operation Machine Operations and Controls

Mechanical Suspension Seat

(if equipped)

Adjust Seat Fore-and-Aft Direction

1. Pull up the fore-aft adjustment lever, and set the seat to
the desired position.
Fore-and-aft adjustment range: 180 mm {7.1 in} (18 steps)
2. After adjusting, release the lever.

How to Recline Seat

The reclining of the seat becomes large when the seat is moved forward, and it becomes smaller as the seat is
moved backward. When moving the seat backward, return the reclined seat back to the original position.
1. Pull up the reclining adjustment lever and set the seat
back to a position which is comfortable for operation.
Foremost reclining: Approx. 66 ° (Approx. 1.9 ° x 35 steps)
Rearmost reclining: Approx. 72 ° (Approx. 1.9 ° x 38 steps)
Sit with your back against the backrest when adjusting. If
your back is not touching the backrest, it may suddenly
move forward.
2. After adjusting, release the lever.

How to Tilt Seat

Pull up the tilt adjustment lever and adjust the front angle of the seat.
• To raise the front of the seat, apply your weight to the rear
of the seat, while pulling up lever.
• To lower the front of the seat, apply your weight to the front
of the seat, while pulling up lever.
Tilt adjustment: Up 5 °, down 5 ° (3 levels)

3-175
Machine Operations and Controls Operation

Adjust Weight and Height of Seat

Pull out the crank of knob (1) under the seat and turn it so that
weight indicator (2) reads the green range. You can adjust the
height by turning knob (1) in the green range.
X: When crank is stored
Y: When crank is pulled out (for adjusting weight)

1. Adjust the weight according to the following procedure.

1) While the seat is moved backward, turn knob (1) to adjust.
Weight adjustment range: 60 to 150 kg {132 to 330 lb}
2) After adjusting the weight, return the crank of knob (1).
2. Adjust the height by turning knob (1) in the green range.
The seat height is increased by turning the knob clockwise (R), seeing from the seated position, and de-
creased by turning the knob counterclockwise (L).
Vertical adjustment range: Stepless 75 mm {3 in}
3. After adjusting the weight and height, readjust the seat to the best position in the forward and backward
directions.

3-176
Operation Machine Operations and Controls

Adjust Lumbar Support

Turn the adjustment knob to the right or left, and give proper
tension to the waist part.
The back cushion tension is increased by turning the adjust-
ment knob to the right.
The tension of the back cushion can be adjusted to 5 steps. If
the adjustment knob is turned to right further after the 5th step,
the tension returns to the 1st step.

How to Heat the Seat

Turn on the seat heater switch.
(a): OFF position
(b): ON position
The backrest and seat surface are heated.

When the seat heater switch is turned on, the heater in the seat operates. When the seat surface temperature
exceeds approximately 20 °C {68 °F} , the heater is turned off automatically. When the temperature decreases
below approximately 10 °C {50 °F} , the heater is turned on automatically.
REMARK
When the seat surface temperature is above approximately 20 °C {68 °F} , the heater does not operate even if
the switch is turned on.

3-177
Machine Operations and Controls Operation

Air Suspension Seat (High-Back Seat)

(if equipped)

Adjust Seat Fore-and-Aft Direction

1. Pull up the fore-aft adjustment lever, and set the seat to
the desired position.
Fore-and-aft adjustment range: 210 mm {8.3 in} (21 steps)
2. After adjusting, release the lever.

How to Recline Seat

The reclining of the seat becomes large when the seat is moved forward, and it becomes smaller as the seat is
moved backward. When moving the seat backward, return the reclined seat back to the original position.
1. Pull up the reclining adjustment lever and set the seat
back to a position which is comfortable for operation.
Forward reclining: Approximately 20 ° (Backrest becomes
free at 20 ° and above.)
Backward reclining: Approximately 60 °
Sit with your back against the backrest when adjusting. If
your back is not touching the backrest, it may suddenly
move forward.
2. After adjusting, release the lever.

How to Tilt Seat

1. Pull up the tilt adjustment lever and adjust the front angle of the seat.
• To raise the front of the seat, apply your weight to the
rear of the seat, while pulling up lever.
• To lower the front of the seat, apply your weight to the
front of the seat, while pulling up lever.
Tilt adjustment: Up 11 °, down 3 °
2. After adjusting, release the lever.

3-178
Operation Machine Operations and Controls

How to Adjust Weight on Seat

When adjusting the seat cushion, turn the starting switch to ON position since the air compressor built in the
seat is used for the adjustment.
NOTICE
Avoid using the height adjustment lever continuously for 1 minute or longer since such practice can
damage the air compressor.
The suspension should be adjusted in proportion to the operator's weight to protect the operator.
After a change of the operator, bleed the air and perform following operations.
Pull up the height adjustment lever fully, and then release it.
The seat cushion is adjusted automatically.
• The weight-based adjustment starts as soon as the height
adjustment lever is pulled lightly. Pull it up fully until it
clicks, and then release it.
• Operate the lever in the normal operating posture to en-
sure the correct weight-based adjustment at this time.
If you stand up from the seat or try to change the load ap-
plied to the seat during adjustment, the air in the suspen-
sion may be released.
After the automatic weight-based adjustment, the seat is the lowest position in the adjustment range.
Adjust the height of the seat.

How to Adjust Seat Height

Turn the engine starting switch to ON position when performing adjustments of seat height since the air com-
pressor built in the seat is used for this adjustment.
NOTICE
Avoid using the height adjustment lever continuously for 1 minute or longer since such practice can
damage the air compressor.
The seat height is adjusted pneumatically and in stepless.
1. When adjusting the seat height, pull up the height adjust-
ment lever fully or push it down fully.
Vertical adjustment range: 80 mm {3.1 in}
When raising it, pull up the height adjustment lever until it
clicks.
When the seat stops while you are pulling up the height
adjustment lever, it is at the maximum position.
If the seat is raised to the maximum height, the suspension
lowers a little automatically to secure some stroke.
Do not set the seat height below the adjustment range,
otherwise, suspension touches to the bottom.
2. After adjusting, release the height adjustment lever.

3-179
Machine Operations and Controls Operation

How to Adjust Seat Cushion in Fore-After Direction

1. Pull up the seat cushion fore-aft adjustment lever, and set
the seat cushion to the desired position.
Fore-aft adjustment range: 60 mm {2.4 in}
2. After adjusting, release the lever.

Adjust Lumbar Support

Adjust the lumber support while keeping the staring switch in ON position.
Press the adjustment switch to give proper tension to the waist
part.
Press (+) side: Tension of backrest increases.
Press (-) side: Tension of backrest decreases.
Adjust the curve of backrest to your desired shape.

How to Adjust Damper

Turn the adjustment knob to adjust the hardness of damper to
the desired level.
Turn to direction (L): Damper is hardened.
Turn to direction (R): Damper is softened.

3-180
Operation Machine Operations and Controls

How to Adjust Mirrors

k WARNING
Be sure to adjust the mirrors before starting work.
If they are not adjusted properly, you cannot secure the visibility and may be injured or may lead to a
serious personal injury or death.

Adjust the mirror by moving it.

Adjust the mirror to a position which gives the best view of the
blind spot from the operator's seat.
In particular, be sure to adjust the mirror so that people at the
rear left or right of the machine can be seen clearly.

How to Adjust Armrest

The R.H. and L.H. armrests of the operator's seat can be adjusted in height in 3 levels. After adjusting the oper-
ator's seat, adjust them to proper height.
1. Loosen bolts (1) on the R.H. and L.H. of the operator's
seat. (2 places each)
2. Adjust the R.H. and L.H. armrests of the operator's seat to
proper height.
3. Tighten bolts (1) securely.
The armrests are fixed.

3-181
Machine Operations and Controls Operation

How to Fasten and Unfasten Seat Belt

k WARNING
• Before fastening the seat belt, check that there is no problem in the belt mounting bracket or belt. If
it is worn or damaged, replace it.
• Even if no problem can be seen in the belt, replace the seat belt every 3 years from starting usage
or 5 years after manufacture whichever comes sooner. The date of manufacture of the belt is shown
on the back of the belt.
• Be sure to use the seat belt during operation.
• Do not twist the seat belt when fastening.

REMARK
The date indicated on the seat belt is the manufactured date. It is the start of the 5-year period. It is not the start
of the 3-year period of actual usage.

Examine Seatbelt
Check for looseness of the mounting bolts of the metal fittings which are installing the seatbelt to the machine.
If they are loosened, retighten them.
Tightening torque: 25 ± 5 Nm {2.5 ± 0.5 kgfm, 18.1 ± 3.6 lbft}
NOTICE
If the seatbelt has flaw, fuzz, breakage, or deformation after long-time use, replace it.

How to Fasten Seat Belt

Sit on the seat, depress the decelerator/brake pedal fully, and adjust the seat so that your back is pressed
against the backrest.
1. Hold grip (2) and pull out the belt from retractable device
(1).
2. Check that the belt is not twisted, and then inset tongue (3)
into buckle (4) securely.
Fit the belt along your body without twisting.

3. Pull the belt lightly to check that it is properly locked.

If the tongue is not inserted in the buckle, the seat belt
caution lamp is displayed at the top left of the machine
monitor.

3-182
Operation Machine Operations and Controls

How to Unfasten Seat Belt

1. Press button (2) in buckle (1) and remove tongue (3) from
buckle (1).
2. Hold grip (4) and slowly return the belt into retractable de-
vice (5).
The belt retracts automatically.

3-183
Machine Operations and Controls Operation

Operations and Checks Before You Start Engine

k WARNING
• When starting the engine, check and make sure park-
ing brake lever (1) and work equipment lock lever (4)
are secured in LOCK position.
If the blade control lever is touched by accident when
starting the engine, the blade may move unexpectedly,
and this may lead to a serious injury or death.
• When standing up from the operator's seat, always set
parking brake lever (1) and work equipment lock lever
(4) to LOCK position, regardless of whether the engine
is running or stopped.

1. Check that battery disconnect switch (S) is in ON position

(I).

2. Check that parking brake lever (1) is in LOCK position (L).

If parking brake lever (1) is not in LOCK position (L), the
engine cannot be started.

3. Check that joystick (steering, directional and gear shift lev-

er) (2) is in NEUTRAL position (N).
The engine cannot be started if joystick (steering, direc-
tional and gear shift lever) (2) is not in NEUTRAL position
(N).

3-184
Operation Machine Operations and Controls

If joystick (steering, directional and gear shift lever) (2) is in

F or R, the letter “P” on speed range display will flash.

4. Lower the blade to the ground.

5. Check that blade control lever (3) is in HOLD position (b).

6. Check that work equipment lock lever (4) is in LOCK posi-

tion (L).
If work equipment lock lever (4) is not in LOCK position
(L), the engine cannot be started.

7. Turn fuel control dial to Low idle (MIN) position.

When the dial is in High idle (MAX) position, be sure to set
it to Low idle (MIN) position.
REMARK
Even if the engine is started with the fuel control dial in a
position other than Low idle (MIN) position, the engine
speed is set to low idle speed.
You can change the engine speed by turning the fuel con-
trol dial to Low idle (MIN) position and then turning it to-
ward High idle (MAX) position.
8. Insert the key into the starting switch and turn it to ON po-
sition (B).

3-185
Machine Operations and Controls Operation

9. On the input display screen displayed on the machine

monitor, input the password and press switch F6.
If a password is set, the input display screen will be indica-
ted on the machine monitor.
REMARK
Contact your Komatsu distributor for details of the method
of setting, changing, or canceling the password.
10. Perform the following inspection on the machine monitor.

1) Check that the buzzer sounds for approximately 2

seconds and the camera image is displayed.

2) Check that the following caution lamp and gauge

lights up for approximately 2 seconds.
• Hydraulic oil temperature gauge (5)
• Engine coolant temperature gauge (6)
• Engine oil pressure caution lamp (7)
• Charge level caution lamp (8)
• Multi-gauge (9)
• Fuel gauge (10)
• Speed range display (11)
If any caution lamp does not light up or the buzzer does not sound, there is probably a failure in the
machine monitor, so ask your Komatsu distributor for repair.
3) Check that the screen changes to the gear shift mode
display screen in approximately 2 seconds, and then it
changes to the standard screen.
• Hydraulic oil temperature gauge (5)
• Engine coolant temperature gauge (6)
• Multi-gauge (9)
• Fuel gauge (10)
• Speed range display (11)
• DEF level gauge (12)
• DEF level caution lamp (13)

3-186
Operation Machine Operations and Controls

4) If the caution lamp stays lit at the position (14), imme-

diately check the lit item.
For details of contents and check methods for caution
lamp, see “Warning Display”.

11. When the maintenance time caution lamp (15) is lit, press
switch F6 to check the item, and perform the maintenance
immediately.
If the maintenance time has passed for certain items,
maintenance time caution lamp (15) is lit for 30 seconds.
For details of the method of checking the maintenance in-
terval, see “Maintenance Screen Setting”

3-187
Machine Operations and Controls Operation

How to Start Engine

How to Start Engine in Normal Weather
k WARNING
• Start the engine only while sitting on the operator's seat.
• Do not attempt to start the engine by short-circuiting the engine starting circuit. This may cause
fire, serious personal injury or death.
• Check that there is no person or obstacle in the area around the machine, then sound the horn and
start the engine.
• Exhaust gas is toxic. When starting the engine in confined spaces, be particularly careful to ensure
good ventilation.
• Do not approach the exhaust pipe outlet of the engine while the engine is running or just after it is
stopped.
Also, keep the combustible materials away from the exhaust pipe outlet.

NOTICE
• Do not turn the starting motor continuously for more
than 60 seconds in any case. If the engine does not
start, wait for approximately 2 minutes, then repeat the
procedure from step 2.
• When starting the engine, if the fuel control dial is at
High idle (MAX) position, the engine will accelerate
suddenly and cause damage to the engine parts.
Before starting the engine, check that the fuel control
dial (1) is at Low idle (MIN) position.
• This machine is equipped with the automatic warm-up
function to heat the coolant more quickly and the tur-
bo protect function to protect the turbocharger. In a
cold weather startup, the engine revolution may not
change for several seconds immediately after the
startup even if the fuel control dial (1) is operated.
• Even if the engine is started with fuel control dial (1) in
a position other than Low idle (MIN) position, the en-
gine speed is set to low idle.
You can change the engine speed by turning the fuel
control dial (1) to Low idle (MIN) position and then
turning it toward High idle (MAX) position.
1. Turn the fuel control dial (1) to Low idle (MIN) position.
When the dial is in High idle (MAX) position, be sure to set
it to Low idle (MIN) position.

3-188
Operation Machine Operations and Controls

2. Turn the key in starting switch (2) to START position (C).

The engine starts.

3. When the engine starts, release the starting switch key (2).
The key will return automatically to ON position (B).

REMARK
• White smoke may be discharged for a short time immediately after the engine is started or during the after-
treatment devices regeneration in cold season, but this is not a failure.
• The smell of the exhaust gas is different from that of the conventional diesel engine because of the exhaust
gas filtering function.

3-189
Machine Operations and Controls Operation

How to Start Engine in Cold Weather

k WARNING
• Start the engine only while sitting on the operator's seat.
• Do not attempt to start the engine by short-circuiting the engine starting circuit. This may cause
fire, serious personal injury or death.
• Check that there is no person or obstacle in the area around the machine, then sound the horn and
start the engine.
• Never use the starting aid fluids to start the engine as they may cause explosions.
• Exhaust gas is toxic. When starting the engine in confined spaces, be particularly careful to ensure
good ventilation.
• Do not approach the exhaust pipe outlet of the engine while the engine is running or just after it is
stopped.
Also, keep the combustible materials away from the exhaust pipe outlet.

NOTICE
• Do not turn the starting motor continuously for more
than 60 seconds in any case. If the engine does not
start, wait for approximately 2 minutes, then repeat the
procedure from step 2.
• When starting the engine, if the fuel control dial is at
High idle (MAX) position, the engine will accelerate
suddenly and cause damage to the engine parts.
Before starting the engine, check that the fuel control
dial (1) is at Low idle (MIN) position.
• This machine is equipped with the automatic warm-up
function to heat the coolant more quickly and the tur-
bo protect function to protect the turbocharger. In a
cold weather startup, the engine revolution may not
change for several seconds immediately after the
startup even if the fuel control dial (1) is operated.
• Even if the engine is started with fuel control dial (1) in
a position other than Low idle (MIN) position, the en-
gine speed is set to low idle.
You can change the engine speed by turning the fuel
control dial (1) to Low idle (MIN) position and then
turning it toward High idle (MAX) position.
1. Turn the fuel control dial (1) to Low idle (MIN) position.
When the dial is in High idle (MAX) position, be sure to set
it to Low idle (MIN) position.

3-190
Operation Machine Operations and Controls

2. Turn the key in starting switch (2) to ON position (B).

3. Check if the preheating pilot lamp on the machine monitor

(3) is lit.
4. Leave this condition until the preheating pilot lamp goes
out.
The time that the preheating pilot lamp stays lit depends
on the ambient temperature as shown in the table.
Ambient temperature
Lighting time (sec.)
(°C)
-4 to -15 {25 to 5} 5 to 30
Max. −15 °C {5 °F} 30

5. After the preheating pilot lamp goes out, turn the key of
starting switch (2) to START position (C), and start the en-
gine.

6. When the engine starts, release the starting switch key (2).
The key will return automatically to ON position (B).
REMARK
Just after starting the engine, run it at low idle. During this
period, release the decelerator/brake pedal and perform
no operation of the work equipment.
7. When the engine speed is stabilized, set the fuel control
dial back to Low idle (MIN) position, and perform the
warm-up operation.

3-191
Machine Operations and Controls Operation

REMARK
• Regardless of the ambient temperature, if the key in starting switch (2) is turned counterclockwise from
OFF position, the preheating pilot lamp lights up and preheating starts. (Preheating continues while the
starting switch (2) is held at the left.)
For the preheating time, see the table in step 5.
• While preheating is being performed, the preheating pilot lamp lights up to indicate that the preheating is
being performed.
• If the engine does not start with the preceding operation, wait for approximately 2 minutes, and repeat the
steps 3 and 4.
• Urea SCR system has the function of heating system and keeping it warm to prevent freezing of DEF.
If DEF is frozen, the DEF system is automatically heated to thaw DEF after the engine is started. The devi-
ces do not operate until DEF is thawed and supplied, but this does not indicate any abnormality.
When the ambient temperature decreases to a level where DEF may freeze while the machine is in opera-
tion, the DEF system is warmed automatically to prevent freezing. When the ambient temperature decrea-
ses to a level where freezing of DEF is not preventable, the devices stop automatically, but this does not
indicate any abnormality.
• If DEF freezes, thawing operation is performed automatically. Never heat the DEF.
Harmful ammonia gas may be generated.
Turbo protect function
The turbo protect function protects the turbocharger by keeping the engine speed at approximately 1075 rpm
immediately after the engine is started.
• When the turbo protect function is actuated, the engine speed is held at 1075 rpm, regardless of the posi-
tion of the fuel control dial.
• When the turbo protect function is actuated, the engine speed is held at 1075 rpm, even if the fuel control
dial is operated.
• When the turbo protect function is canceled, the engine speed is set to the speed for the position of the fuel
control dial.
• The actuation time of the turbo protect function is limited to 20 seconds.
Automatic warm-up function
The automatic warm-up function increases the idle speed to 1200 rpm or more to increase the engine coolant
temperature quickly during operation at low temperature.
When the turbo protect function and automatic warm-up function operate at the same time, the turbo protect
function is given priority.
• When the automatic warm-up function is actuated, the engine speed is held at 1200 rpm, even if the fuel
control dial is turned to a position of 1200 rpm or less.
However, if the fuel control dial is held at High idle (MAX) position for more than 3 seconds, the auto warm-
up function is canceled and then the engine speed can be lowered to 1200 rpm or less.
• The automatic warm-up function continues operation until the engine coolant temperature reaches 30 °C
{86 °F} or up to 10 minutes.
• If the decelerator/brake pedal is depressed while the automatic warm-up function is in operation, the auto-
matic warm-up function is canceled and the engine speed decreases to 1200 rpm or less.

3-192
Operation Machine Operations and Controls

Operations and Checks After You Start Engine

k WARNING
• If there has been any emergency stop, abnormal actuation or trouble, turn the starting switch key to
OFF position.
• If the work equipment is operated without sufficient warming-up operation of the machine, response
of the work equipment to movement of the control lever will be slow, and the work equipment may
not respond as the operator desires, so always perform the warming-up operation. Particularly in a
cold weather, be sure the warm-up operation is completed.
• If the machine is operated without sufficient warming-up operation, sensors may break because of
frozen DEF tank.

How to Examine Starting Condition and Unusual Noise of Engine

• When starting the engine, check that the engine causes no abnormal noise and that it starts up easily and
smoothly.
• Check that there is no abnormal noise when the engine is idling or when the engine speed rises slightly.
When there is an abnormal noise at the engine startup and if that condition continues, the engine may be dam-
aged. In that case, ask your Komatsu distributor to check the engine as soon as possible.

How to Examine Low-Speed Run and Acceleration of Engine

• When stopping the machine during the normal traveling operation, check that the engine does not hunt or
stop suddenly.
• Check that the engine speed rises smoothly when the fuel control dial is turned to High idle (MAX) position.
• Perform these checks in a safe place, watching out for danger in the surroundings.
• When the engine performs very badly at low idle and in the acceleration and if that condition continues,
it may damage the engine or confuse the operator's sense of driving or lower the braking efficiency,
and as a result lead to an unexpected accident. In that case, ask your Komatsu distributor to check the
engine as soon as possible.
REMARK
• The smell of the exhaust gas is different from that of the conventional diesel engine because of the
exhaust gas filtering function.
• Black or white smoke may be discharged for a short time just after the engine is started in the cold
season, but this is not trouble.

3-193
Machine Operations and Controls Operation

Operate Engine in Break-in Period

NOTICE
Your Komatsu machine has been thoroughly adjusted and tested before shipment from the factory.
However, operating the machine under full load before breaking the machine in can adversely affect the
performance and shorten the machine life.
Be sure to break in the machine for the initial 100 hours (as indicated on the service meter).
Make sure that you fully understand the descriptions in this manual, then run in the machine while paying atten-
tion to the following points.
• Run the engine at idle for 15 seconds immediately after starting it up.
Do not operate the control levers or fuel control dial during this time.
• Perform warm-up operation for 5 minutes after the engine is started.
• Avoid operation with heavy loads or at high speeds.
• Immediately after starting the engine, avoid sudden starts, sudden acceleration, unnecessary sudden
stops, and sudden changes in direction of the machine.

Engine Warm-up Operation

NOTICE
• Do not perform operations or operate the levers sharp-
ly while the hydraulic oil is at low temperature. Always
perform the warm-up operation until the hydraulic oil
temperature caution lamp shows the green display.
This will extend the service life of the machine.
Do not accelerate the engine abruptly until it is
warmed up.
• Do not run the engine at low idle or full throttle with no
load for 20 minutes and more. This will have an ad-
verse effect on the environment and also on the inter-
nal structure of the turbocharger and engine. If it is
necessary to run the engine at idling, apply a load
from time to time or run at a medium speed.
• If the engine oil pressure caution lamp on machine
monitor (2) lights up or the alarm buzzer sounds inter-
mittently, stop the engine and perform inspection.

1. Turn fuel control dial (1) to a position midway between Low

idle (MIN) and High idle (MAX).
The engine runs at a medium speed.
2. Run it with no load (perform warm-up operation) for ap-
proximately 5 minutes.
3. After the warm-up operation, check that each gauge and
caution lamp indicate the normal values.
If any problem is found, perform maintenance or repair.

3-194
Operation Machine Operations and Controls

4. Operate the machine under light load until the engine cool-
ant temperature gauge and hydraulic oil temperature
gauge on machine monitor (2) indicates green range (A) to
(C).
• (A) to (B): Red range
• (A) to (C): Green range
• (C) to (D): White range
5. Check for abnormal exhaust gas color, noise, or vibration.
If any abnormality is found, contact your Komatsu distribu-
tor.

Engine Warm-up Operation in Cold Season

This machine is warmed up automatically by the automatic
warm-up operation system.
When the engine coolant temperature is 30 °C {86 °F} or less
after the engine is started, the warm-up operation starts auto-
matically.
The automatic warm-up operation stops when the engine cool-
ant temperature increases the specified temperature (30 °C
{86 °F} ) or after warm-up operation of 10 minutes even if the
coolant temperature does not increase to 30 °C {86 °F} .
After the automatic warm-up operation, if the engine coolant
temperature or hydraulic oil temperature is low, perform addi-
tional warm-up operation according to the following procedure.
1. Turn fuel control dial (1) to a position midway between Low
idle (MIN) and High idle (MAX).
The engine runs at a medium speed.
2. Run it with no load (perform warm-up operation) for ap-
proximately 10 minutes.

3-195
Machine Operations and Controls Operation

3. Raise the blade to the highest position by operating blade

control lever (2).
4. Repeat the following relief operations for 5 minutes with
the blade raised to the highest position.
1) Operate slowly LEFT TILT relief.
2) Operate slowly RIGHT TILT relief.
5. Next, repeat the following relief operations for 5 minutes.
1) Operate blade control lever (2) to RAISE position (a)
(at lever stroke end) and hold it in that position, then
perform RIGHT and LEFT TILT relief operations inter-
mittently.
2) Lower the blade to the ground.
3) While pressing FLOAT button, tilt blade control lever (2) to the stroke end to set it in FLOAT position,
and then perform RIGHT and LEFT TILT relief operations intermittently.
4) Raise the blade to the highest position.
6. After completing relief operations, lower the blade to the ground.
7. While pressing FLOAT button, tilt blade control lever (2) to the stroke end, and hold it with your hand for 1
minute.
8. After 3 minutes of releasing your hand, set the blade control lever (2) to RAISE position (a) once, and re-
lease FLOAT.
9. After the warm-up operation, check that each gauge and caution lamp indicate the normal values.
If any problem is found, perform maintenance or repair.
10. Operate the machine under light load until the engine cool-
ant temperature gauge and hydraulic oil temperature
gauge on machine monitor (3) indicate green range (A) to
(C).
(A) to (B): Red range
(A) to (C): Green range
(C) to (D): White range
NOTICE
If the hydraulic oil temperature is low, the machine
may deviate a little at moving off or stopping. If it is
necessary to operate the machine when the hydraulic
oil temperature gauge is at white range (C) to (D), be
extremely careful.
11. Check for abnormal exhaust gas color, noise, or vibration.
If any abnormality is found, contact your Komatsu distribu-
tor.

After warm-up operation, run he engine at medium speed and slowly drive forward and reverse so that the
whole equipment becomes uniform temperature.

3-196
Operation Machine Operations and Controls

How to Stop Engine

k WARNING
Keep away from the exhaust pipe immediately after stopping the engine.

NOTICE
• If the engine is abruptly stopped before it has cooled
down, service life of the engine parts may be reduced.
Do not stop the engine abruptly except in an emergen-
cy.
If the engine overheats, do not stop it suddenly. Run it
at low speed to allow it to cool down gradually, then
stop it.
• If the engine is stopped during the aftertreatment devi-
ces regeneration, the components may be damaged.
Stop the regeneration first, then stop the engine as fol-
lows.
• When the engine is stopped during or just after the af-
tertreatment devices regeneration is finished, the parts
around the aftertreatment devices may become high
temperature. Take care.
1. Lower the work equipment to the ground.
2. Turn the fuel control dial (1) to Low idle (MIN) position.
3. Run the engine at low idle for approximately 5 minutes to
cool down gradually.

4. Turn the key in starting switch (2) to OFF position (A).

The engine will stop.
5. Remove the key from the starting switch (2).
When you stop the engine, the regeneration disable set-
ting is canceled. If necessary, disable the regeneration
again after you start the engine.

3-197
Machine Operations and Controls Operation

REMARK
• When the key in starting switch (2) is turned to OFF
position, the engine stops, but the machine's main
power supply is not turned off immediately.
During this period, the power is supplied to the con-
troller to save the operating condition and then finish
the system. The time to keep supplying the power de-
pends on the operating condition.
• Also when the cooling fan is turned in reverse, the ma-
chine's main power supply is not turned off immediate-
ly, even if the key in engine starting switch (2) is
turned to OFF position.
This is for protection of the hydraulic circuit, and the
power is kept supplied for 7 seconds.
• If the starting switch (2) key is turned to OFF position
(A) while the engine is still hot, guidance (3) may be
displayed on the machine monitor. This may cause
damage to the devices. To cool down the engine be-
fore stopping, run it at low idle from the next time and
after.
• After the engine is stopped, DEF in DEF injector and
pump is automatically purged and returned to the tank
to prevent malfunction of the devices caused by freez-
ing of DEF or deposition of urea.
For this purpose, the devices keep operating up to 7
minutes after the key in starting switch (2) is turned to
OFF position, and this does not indicate abnormality.
In addition, the system operating lamp lights up while
devices are operating to purge the DEF to the tank.
Do not turn the battery disconnect switch to OFF posi-
tion while the system operating lamp is lit. After DEF
has been purged completely, the devices stop auto-
matically.

3-198
Operation Machine Operations and Controls

How to Start Machine (Travel FORWARD and REVERSE) and Stop Ma-
chine
Move Machine
k WARNING
• Before moving the machine off, check that the area
around the machine is safe, then sound the horn be-
fore starting.
• Keep people away from the machine.
• The area behind the machine is a blind spot. Pay atten-
tion particularly when traveling in reverse.
• When moving off the machine on a slope, always keep
decelerator/brake pedal (2) depressed, even after re-
leasing parking brake lever (1).
• When moving off the machine on a steep uphill, turn
fuel control dial (3) to High idle (MAX) position and run
the engine at full speed.
Depress decelerator/brake pedal (2) fully, select 1st
speed, and set joystick (steering, directional and gear
shift lever) (4) to the direction to move off.
Begin to release decelerator/brake pedal (2) gently,
and when the machine moves off slowly (or shoe slip),
release decelerator/brake pedal (2) fully.
• When decelerator/brake pedal (2) is depressed or fuel
control dial (3) is set in Low idle (MIN) position on a
flat ground, the machine is stopped but it does not
mean that brake is applied.
• On slopes, the machine moves even at low idle, so be
extremely careful.

1. Operate the parking brake lever (1) by holding the operat-

ing portion on the top, and place the lever in FREE posi-
tion (F)

2. Operate joystick (steering, directional and gear shift lever)

(4), and check that desired speed range is set on the
speed range display of machine monitor (5).

3-199
Machine Operations and Controls Operation

3. Be sure to operate the lock lever (6) by the red portion on

the top, then set it to FREE position (F).

4. Set blade control lever (7) to RAISE position (R) and raise
the blade to 40 to 50 above the ground.

5. Depress the decelerator/brake pedal (2).

6. Set the joystick (steering, directional and gear shift lever)

(4) to FORWARD position (F) or REVERSE position (R).
REMARK
Check that the backup alarm sounds when the joystick
(steering, directional and gear shift lever) is set to RE-
VERSE position. If the alarm does not sound, ask your Ko-
matsu distributor for repair.

7. Turn the fuel control dial (3) to High idle (MAX) position.

3-200
Operation Machine Operations and Controls

8. Make the machine move off by releasing decelerator/brake

pedal (2) gradually.
REMARK
When moving off, the machine sometimes deviates a little,
but this is due to actuation of straight-travel correction
mechanism and it is not a failure.

3-201
Machine Operations and Controls Operation

Stop Machine
k WARNING
• Avoid a sudden stop. Stop the machine gradually.
• Do not park the machine on a slope.
If it is unavoidably necessary to park the machine on a
slope, place parking brake lever (1) in LOCK position
and insert blocks underneath the track shoes to pre-
vent the machine from moving. As an additional safety
measure, thrust the work equipment into the ground.
• If the blade control lever is touched by accident, the
blade may suddenly move, and this may lead to a seri-
ous accident. Set the work equipment lock lever (2) to
LOCK position always before leaving the operator's
seat.

1. Depress the decelerator/brake pedal (3).

2. Return the joystick (steering, directional and gear shift lev-

er) (4) back to NEUTRAL position (N).
The machine stops.

To keep the machine stopped, depress decelerator/brake

pedal (3) further until depressing effort becomes large.

3-202
Operation Machine Operations and Controls

How to Shift Gears

Speed range can be changed while traveling, it is not necessary to stop the machine for gear shifting.
Select a desired speed range by depressing UP switch or
DOWN switch of joystick (steering, directional and gear shift
lever) (1).

How to Shift Gears

Shift the speed range by pressing UP switch (U) or DOWN
switch (D).
UP switch (U): The speed range is shifted up by 1 step each
time this switch is pressed.
DOWN switch (D): The speed range is shifted down by 1 step
each time this switch is pressed.
When the starting switch is turned to ON position, speed range
is automatically set to 1st speed.

Change Gear Shift Mode

In the gear shift mode, quick shift mode and variable shift mode are available.
Select the mode to match the use. For the use, see “Features of Modes”.
Press the gear shift mode selector switch when in NEUTRAL.
Quick shift mode and variable shift mode are switched.

3-203
Machine Operations and Controls Operation

Quick Shift Mode

• Press UP switch (U) of the joystick (steering, directional
and gear shift lever) once, and speed range changes 1st
→ 2nd and 2nd → 3rd.
• Press DOWN switch (D) of the joystick (steering, direction-
al and gear shift lever) once, and speed range changes
3rd → 2nd and 2nd → 1st.

• The directional condition is displayed on column (E) of the

speed range display and the speed range condition is dis-
played on column (F).
Directional display (E)
“F”: FORWARD
“R”: REVERSE
Speed range display (F)
“1”: 1st
“2”: 2nd
“3”: 3rd
(Example) In case of FORWARD 2nd: F2
When the directional condition is NEUTRAL, “N” is displayed between the directional display (E) and speed
range display (F).
When the parking brake is being applied, “P” is displayed between the directional display (E) and speed
range display (F).
• Upper bar graph (G) lights up in accordance with the set travel speed in forward.
• Lower bar graph (H) lights up in accordance with the set travel speed in reverse.
• When the starting switch is turned from OFF to ON position, the speed range is set to 1st speed.

3-204
Operation Machine Operations and Controls

Variable Shift Mode

• Each time UP switch (U) on the joystick (steering, direc-
tional and gear shift lever) is pressed, upper bar graph
lights up by 2 segments and travel speed is increased by
approximately 0.4 km/h {0.2 MPH} .
• If UP switch (U) on the joystick (steering, directional and
gear shift lever) is kept pressed, upper bar graph segment
lights up continuously, and you can set the speed range
when you release the switch.
• To lower the travel speed, operate DOWN switch (D) on
the joystick (steering, directional and gear shift lever) in the
same manner.
• FORWARD/REVERSE (E) is displayed in the speed range
display section.
FORWARD/REVERSE (E)
“F”: FORWARD
“R”: REVERSE
“N”: NEUTRAL
“P”: Parking brake is being applied
• Upper bar graph (G) lights up in accordance with set travel
speed in forward.
• Lower bar graph (H) lights up in accordance with set travel speed in reverse.
• When the starting switch is turned from OFF to ON position, the speed range is set to 1st speed.
• When switching from variable shift mode to quick shift mode, the speed range becomes nearest one among
1st, 2nd, and 3rd.
• For the lighting up of bar graph (G) and (H) and set travel speed, see the following table.

Bar Speed Set travel speed Bar Speed Set travel speed Bar Speed Set travel speed
graph range (km/h {MPH} ) graph range (km/h {MPH} ) graph range (km/h {MPH} )
1 15 27
- 0.8 {0.5} - 3.8 {2.4} - 6.1 {3.8}
2 16 28
3 17 29
- 1.0 {0.6} - 4.1 {2.5} - 6.6 {4.1}
4 18 30
5 19 31
- 1.5 {0.9} - 4.5 {2.8} - 7.1 {4.4}
6 20 32
7 21 33
- 2.0 {1.2} - 4.9 {3.0} - 7.5 {4.7}
8 22 34
9 23 35
- 2.4 {1.5} - 5.2 {3.2} - 8.0 {5.0}
10 24 36
11 25 37
- 2.9 {1.8} 2nd 5.6 {3.5} - 8.5 {5.3}
12 26 38
13 39
1st 3.4 {2.1} - - - 3rd 9.0 {5.6}
14 40

3-205
Machine Operations and Controls Operation

REVERSE Travel Speed Settings

Reverse travel speed can be set by selecting the ratio of reverse travel speed against forward travel speed out
of the following 5 levels.
“-1”: Approximately 20 % slower than forward travel speed.
“0”: Same as forward travel speed.
“+1”: Approximately 20 % faster than forward travel speed.
“+2”: Approximately 40 % faster than forward travel speed.
“+3”: Approximately 60 % faster than forward travel speed.
By setting the travel speed according to the operation in advance, gear shifting is not necessary when operating
the joystick (steering, directional and gear shift lever).
To improve efficiency in dozing operation, increase the reverse travel speed.
When traveling in reverse on the rough ground or dozing uphill, decrease the reverse travel speed.
• Reverse travel speed can be set with reverse travel speed
setting switch (A) and (B).
• Each time switch (A) is pressed, the set travel speed in-
creases.
• Each time switch (B) is pressed, the set travel speed de-
creases.
• Lower bar graph (H) indicates the reverse travel speed.
• Turn the starting switch in ON position and start the en-
gine, reverse travel speed is set approximately 20 % faster
than the forward travel speed.
• Depress switch (B) once, and the reverse travel speed be-
comes the same as the forward travel speed.
• 3rd speed is the maximum, so reverse travel speed cannot
be set faster than that.

3-206
Operation Machine Operations and Controls

How to Switch Between FORWARD and REVERSE

k WARNING
When switching the travel direction between FORWARD
and REVERSE, check the safety in new direction in which
the machine moves.

k CAUTION
There is no need to stop the machine even when switching
between FORWARD and REVERSE. To increase safety, op-
erator comfort, and the life of the power train system, do
not leave the engine running at full speed while switching
the direction, and always depress the decelerator/brake
pedal to lower the engine speed.

1. Depress decelerator/brake pedal (1) to reduce the engine

speed.

2. Set joystick (steering, directional and gear shift lever) (2) to

a desired position.
Position (F): FORWARD
Position (N): NEUTRAL
Position (R): REVERSE
Check that the backup alarm sounds when the joystick
(steering, directional and gear shift lever) is set to RE-
VERSE.
If the alarm does not sound, ask your Komatsu distributor
for repair.
3. Release decelerator/brake pedal (1) and raise the engine
speed.
REMARK
When moving off, the machine sometimes deviates a little,
but this is due to actuation of straight-travel correction
mechanism and it is not a failure.

3-207
Machine Operations and Controls Operation

Steer Machine
k WARNING
• Avoid turning on a slope whenever possible, since sideways slip occurs easily.
Take care particularly on soft ground or clay land.
• Do not make a pivot turn at a high speed.

Method for Normal Turning Operation

During travel, tilt joystick (steering, directional and gear shift
lever) (1) in a direction you want to turn.
The machine turns in a direction in which joystick (steering, di-
rectional and gear shift lever) (1) is tilted.

Turn Machine During FORWARD Travel

When gradually turning to the left, tilt the joystick (steering, di-
rectional and gear shift lever) forward and tilt it to left (L) half-
way.
Any turning radius can be set until the operating effort of joy-
stick (steering, directional and gear shift lever) becomes large.
REMARK
When gradually turning to the right, tilt the joystick (steering, di-
rectional and gear shift lever) forward and tilt it to right halfway.
Operate similarly during reverse travel.

3-208
Operation Machine Operations and Controls

Operate Counter-Rotation Turn

NOTICE
• Before performing a counter-rotation turn, check the safety around the machine.
• When performing a counter-rotation turn, if the load is not equal on the left and right sides, the ma-
chine may perform a pivot turn, so check the ground conditions and be careful not to hit any obsta-
cles.
REMARK
When the steering mode is set to the fine mode, the machine cannot make counter-rotation turn.
1. Check that the steering mode is set to the normal mode.
When the steering mode is not set to the normal mode, set
it to the normal mode according to the following procedure.
1) Press the switch F1 on the standard screen to display
“Mode Select” screen.

2) On “Mode Select” screen, select “Steering Mode” and

press the switch F6.

3) On “Steering Mode” screen, press the switch F3 or F4

to move the yellow cursor to “Normal”, then press the
switch F6.

3-209
Machine Operations and Controls Operation

2. To make counter-rotation turn to the left, tilt the joystick

(steering, directional and gear shift lever) forward and tilt it
to left (L), and tilt it fully further from the point where the
joystick operating effort becomes large.
The R.H. and L.H. tracks rotate in the opposite directions
to each other to make counter-rotation turn on that place.
REMARK
To make counter-rotation turn to the right, operate the joy-
stick (steering, directional and gear shift lever) to the right
in the same manner.

3-210
Operation Machine Operations and Controls

How to Turn Machine During Downhill Travel

Turn Machine Gradually During FORWARD Downhill Travel
When gradually turning to the left, tilt the joystick (steering, di-
rectional and gear shift lever) forward and tilt it to left (L) half-
way.
Any turning radius can be set until the operating effort of joy-
stick (steering, directional and gear shift lever) becomes large.
Cross steering does not occur.
REMARK
When gradually turning to the right, tilt the joystick (steering, di-
rectional and gear shift lever) forward and tilt it to right halfway.

3-211
Machine Operations and Controls Operation

Recommended Working Modes for Works

Features of Modes
Gear Shift Mode
Gear shift mode can be changed with gear shift mode selector switch (1).
Gear shift mode Features
Travel speed is set to suit the general work load and gear shifting is easy. This is ef-
Quick shift fective for the operator who is accustomed to 3 speeds gear shifting pattern or for the
work which requires frequent gear shifting.
Travel speed can be set in 20 levels between 0.8 and 9.0 km/h {0.5 and 5.6 MPH} .
Variable shift In particular, minimum travel speed is set low and it ensures the safe work for loading
to the trailer or riding over unevenness of the road.

Operating Mode
Operating mode can be changed with operating mode selector switch (2).
Operating mode Features
P Full power is generated, so use this mode for operations on uphill slopes or when
(Power mode) handling large volumes of soil.

Use this mode when it is desired to reduce fuel consumption.

E Use this mode for soil or operations where the shoes tend to slip and where decelera-
tion operations are needed.
(Economy mode)
Use this mode for pushing-down operations and grading operations where power is
not needed.

Pedal Mode
Pedal mode can be changed with pedal mode selector switch (3).
Pedal mode Features
Depress the decelerator/brake pedal, and travel speed and engine speed lowers.
Decelerator mode
Use this mode for general operations.
Depress the decelerator/brake pedal, and the travel speed lowers, but the engine
speed does not lower.
Brake mode
Use this mode when you want to lower the travel speed but keep the work equipment
speed.

Blade Mode
Blade response can be changed on the mode selector screen.
Blade mode Features
Starting of operation for blade RAISE and LOWER becomes quick, and movement of
FAST
the work equipment corresponding to the lever stroke also becomes quick.
NORMAL Blade response of RAISE and LOWER is optimized for general operations.
Starting of operation for RAISE and LOWER becomes smooth, and the operating
FINE range on the lever stroke corresponding to the movement of the work equipment be-
comes wider.

Steering Mode
Steering mode can be changed on the Mode Select screen.

3-212
Operation Machine Operations and Controls

Steering mode Features

When lever is tilted to the point where the lever operating effort becomes heavy, the
inside track of turning machine stops and the machine starts pivot turn. When lever is
NORMAL
tilted further, stopped track starts rotating in reverse and the machine starts counter-
rotation turn.
Even if lever is tilted to the point where the lever operating effort becomes heavy, the
inside track of turning machine continues rotating. When the lever is tilted further to
FINE
the stroke end, the inside track stops rotating, and the machine starts making pivot
turn.

AA: Standard screen, MM: “Mode Select” screen

(1) Gear shift mode selector switch (3) Pedal mode selector switch
(2) Operating mode selector switch

3-213
Machine Operations and Controls Operation

Recommended Working Modes

Operating mode
Type of operation Soil quality Operating conditions
P E
Normal soil Heavy-duty operations, high productivity desired ○ -
Sand, soft soil Light-duty operations, easily slips - ○
Digging, hauling
Uneven ground, soft
Load changes easily - ○
rock
Pushing up Uphill ○ -
Pushing down Downhill - ○
Grading, leveling Light-duty operations - ○
Uneven ground, soft
Ripping Shoes slip easily - ○
rock
Removing stumps, side cutting - ○ -

3-214
Operation Machine Operations and Controls

Precautions for Operation

Watch Gauges
If the hydraulic oil temperature caution lamp lights up during operation, reduce the load and wait for the temper-
ature to go down.

Allowable Water Depth

When operating in water, always keep the bottom of carrier roll-
ers (1) above the surface of the water. Also, be careful that the
hydraulically driven cooling fan will not come in contact with
water in order to prevent the breakage of the fan.
After using the machine in the water for a long time, grease the
work equipment and equalizer bar through each grease fitting.

Precautions for Long-Time Travel

Avoid operating the machine at high speed for a long time, oth-
erwise the temperature of lubricating oil sharply rises, and that
can cause oil leakage from the track rollers or final drive and
lower durability.
If there is no way to avoid operating the machine at high speed
for a long time, stop the machine every one hour for 30 minutes
and let the track rollers and final drive cool off before starting
up the machine again.

Precautions for Downhill Travel

Use Engine Brake
When driving downhill, move the joystick (steering, directional and gear shift lever) into low speed range to run
the engine at low speed and drive down slope by using the engine brake.
Do not move the joystick (steering, directional and gear shift lever) to N (NEUTRAL) position.
When driving downhills of 15 ° or more, use R1 or F1.
REMARK
When the machine travels downhill in straight, you may feel a little sway laterally. This is due to control of
straight-travel correction and it is not a trouble.

Brake on Downhill
When traveling downhill with the engine brake applied, use the brake as necessary to prevent overrun. Overrun
can cause a failure.

3-215
Machine Operations and Controls Operation

Precautions When You Work on Slope

Be Careful of Fuel Level
If the fuel level in the fuel tank becomes low when working on slopes, the engine may suck in air because of the
angle of the machine or the swaying of the machine. This makes the engine stop, so be careful not to let the fuel
level in the fuel tank become too low.
When working on slopes with an angle of more than 20 °, if the
fuel level on the fuel gauge enters the red range, add fuel im-
mediately.
(A): Red range
(B): Green range

Be Careful of Oil Level

When operating machine on a slope of 20 ° or more, fill all components with oil to H level.
Be Careful of DEF Level
Before working on a slope or traveling on a rough ground, check DEF tank and add sufficient amount of DEF as
necessary. If the remaining DEF level becomes low, sudden drop of its level or abnormality in urea SCR system
may be detected. If DEF level caution lamp or DEF system caution lamp lights up in red, move the machine to a
level place immediately and add DEF.
Be Careful of Stall Engine on Slopes
If the engine stops while working or traveling on a slope, immediately depress the decelerator/brake pedal to
stop the machine completely.

Do Not Open Door While You Operate Machine

Always keep the door closed when traveling or performing operations.
If the door is open, it may be damaged by obstacles or strong vibration.

Do Not Change CAB Glass in Any Way that Will Block the View
Never install anything which obstructs the view and affects the safety to the glass.
Keep the glass clean and secure the safety for the work.

Precautions for Floating Operation

If the blade is operated to FLOAT when the engine is running at low speed or when it is idling, hunting may
occur.
Raise the engine speed when performing FLOAT operation.

3-216
Operation Machine Operations and Controls

Precautions for Blind Areas Caused by CAB and ROPS Structures

k WARNING
The cab stays create blind spots.
When operating, check carefully that there is no person or
obstacle in the surrounding area.

Recommended Applications
In addition to the following, it is possible to further increase the range of applications by using various attach-
ments.

Dozing Work
Cut soil and sand and move them forward. When cutting a
slope surface, it is more efficient to always cut from top toward
bottom.

When dozing toward one side only, operate with angled blade.

REMARK
If the blade is hard to be raised during digging, adjustment of the blade edge angle will improve the condition.
For the adjustment method, see “Adjust Blade Edge Angle”.

3-217
Machine Operations and Controls Operation

Leveling Work
NOTICE
Avoid leveling work on rocky or stony ground. It can damage the blade.
To finish the ground to a flat surface after digging or piling soil,
put a full load of soil on the front face of the blade and operate
the blade up and down in small movements while traveling for-
ward.
Finally, float the blade travel at low speed in reverse while pull-
ing the blade over the ground surface.
At this time, tilt the blade control lever to the stroke end secure-
ly while pressing FLOAT button.
Avoid running over stones or rocks to protect the blade.

3-218
Operation Machine Operations and Controls

Works to Cut and Ditch Hard or Frozen Ground

For digging and ditch excavation of hard or frozen ground, tilt
the blade. Even hard ground can be dug effectively by a tilted
or angled blade.

Works of Felling Trees and Removing Stumps

NOTICE
Do not perform stump removal or other hard work by angling tilting the blade.
For trees with a diameter of 10 to 30 cm {3.9 to 11.8 in} , raise
the blade high and push a few times to fell the tree.
Next, travel in reverse, and dig the corner of the blade into the
ground to cut and dig up the roots.
When doing this, never hit the tree at high speed or apply
shock to fell the tree.

Side-Cut Operation
In side cutting operation with unbalanced load on the blade,
use the counter-rotation turn to change the travel direction. As
a result, the operation becomes efficient.

3-219
Machine Operations and Controls Operation

How to Adjust Work Equipment

For adjusting the play of center ball, see “Adjust Shim of Center Ball”.

Adjust Blade Edge Angle

Mechanical type pitching rod (variable type)

k WARNING
It is dangerous if the work equipment moves by mistake when the blade edge angle is adjusted.
Set the work equipment in a stable condition, then stop the engine. Set the work equipment lock lever to
LOCK position securely.

NOTICE
• The rod has 2 lines of (a) and (b) which show the ad-
justment position of pitch angle adjustment. Do not
extend it more than 60 ° line (a) on the blade edge an-
gle.
The blade edge angle can be adjusted to meet the soil
conditions.
• When operation is performed at stroke end while the
pitch angle exceeds the forward pitch limitation (rod
length 510 mm {20.1 in} or more), the piston nut may
become loose due to the external load applied to it.
When the bracket tip (1) does not contact to the rod,
the pitch angle exceeds the forward pitch limitation.
When the operation requires the pitch angle to extend
beyond the forward pitch limitation, do not perform the
full-angling operation of the blade.
1. Lower the blade to the ground.
2. Loosen the bolt (2).
3. Turn the rod (3) to adjust the pitch angle forward or rear-
ward.
Wide/ High ca-
Length be- narrow pacity
No. Adjustment tween rods blade blade
(L) Blade edge Blade edge
angle (A) angle (A)
Forward 530 mm
(a) 60 ° 58 °
(Maximum) {20.9 in}

510 mm
(b) Standard 57 ° 55 °
{20.1 in}
Rearward 485 mm
(c) 53 ° 51 °
(Minimum) {19.1 in}

REMARK
When the maximum cutting angle (blade tilted fully forward) is changed to the minimum cutting angle (blade
tilted fully rearward), there is resistance from the pressure stored in the angle cylinder, so the operating ef-
fort may gradually become heavier.
In this case, turn the starting switch to ON position (you do not need to start the engine), and then cancel
the work equipment lock lever, set the blade control lever in the angling direction, and release the pressure
in the angle cylinder.

3-220
Operation Machine Operations and Controls

4. Install the bolts (2).

Tightening torque: 490 to 608 Nm {50 to 62 kgfm, 362 to 448 lbft}

3-221
Machine Operations and Controls Operation

Tips for Longer Undercarriage Life

Undercarriage life greatly varies depending on operation method, inspection and maintenance.
For most efficient operation, keep the following points in mind.

Operate
• Use a track shoe suitable for soil condition.
For selection of the shoe, consult your Komatsu distributor.
• Do not let the shoe slip during operation.
If the shoe starts slipping, decrease the load to prevent slipping.
• Avoid rapid start, acceleration, stop, or unnecessary high-speed operation or sharp turn.
• Drive the machine as straight as possible. Do not turn only in either direction but turn in both directions
evenly. Also, secure turning radius as large as possible.
• Clear the travel ground and remove obstacles so that the machine does not ride over large boulders or ob-
stacles.
• On slopes, do not work across the slope surface but work
upward or downward. When stopping the machine on a
slope, direct it up or down.
• If the ground slants to the right or left while the machine is
digging, do not stay there but move back to a level place,
then start digging again.
• If the idler or sprocket floats because of a hard obstacle
during dozing or ripping work, avoid that obstacle, since it
is “difficult to move it”.

How to Examine and Adjust

• Adjust the track tension to a proper level.
Check the tension by measuring clearance (a) between
the idler and carrier roller shown in the figure. This clear-
ance should be 20 to 30 mm (0.8 to 1.2 in) usually. Howev-
er, tense a little higher for rocky terrain and a little lower for
clay land.
Extremely low track tension can cause abnormal vibration
or abnormal wear of sprocket teeth.
For the testing and adjusting method, see “How to Exam-
ine and Adjust Track Tension”.
• Check the idler and rollers for oil leakage and loose bolts
and nuts.
Repair any abnormality immediately.
• Check a clearance (B) between front idler guide plate (1)
and track frame (2).
As clearance (B) becomes larger, it can cause the front id-
ler to sway sideways and cause the track shoe to jump off
rollers.
For the testing and adjusting method, see “How to Adjust
Idler Clearance”.

3-222
Operation Machine Operations and Controls

How to Examine and Repair

Frequent inspection and prompt repair will reduce repair costs.
The following items for inspection will serve as a guide to maintenance service of each undercarriage part. Per-
form periodical inspection and contact the Komatsu distributor in your area when machine has approached re-
pairable limits and reversing limits.

Method for Measure Link Pitch

1. Put a wooden block, etc. between the track shoe and
sprocket to eliminate the sag of the track.

2. Measure length (L) of 4 link pitches in a straight portion at

least 2 links apart from master link (A).
1/4 of the measured value is the link pitch.
Standard link pitch (P): 175.3 mm {6.9 in}
Turning limit link pitch of bushing: 178 mm {7 in}
The master link has no link window.
REMARK
The decimal portion of the measured value of link pitch
may be different from standard link pitch (P), depending on
the measurement accuracy and machining tolerance, even
if the track is not worn. Do not judge the track is worn by
only the value measured now, but judge by the trend of the
later measured values.

Measure Grouser Height

Eliminate the sag of the track, and measure at the center of the
track.
Standard dimension (h): 55 mm {2.2 in}
Repairable limit: 25 mm {1 in}

3-223
Machine Operations and Controls Operation

Measure Track Roller Diameter

1. Measure the link tread (dimension C) as shown in the fig-
ure.
2. Stop the machine at a position where the link tread, at
which dimension C was measured, is perfectly in contact
with the roller tread.
3. Measure dimension B.
4. Calculate outside diameter of the tread (dimension A).
A = (B - C) x 2
Standard dimension (A): 185 mm {7.3 in}
Repairable limit: 160 mm {6.3 in}

3-224
Operation Machine Operations and Controls

How to Park Machine

k WARNING
• Avoid a sudden stop. Stop the machine gradually.
• Place the machine on a firm, level ground.
Do not park the machine on a slope.
If it is unavoidably necessary to park the machine on a
slope, place parking brake lever (3) in LOCK position
and insert blocks underneath the track shoes to pre-
vent the machine from moving. As an additional safety
measure, thrust the work equipment into the ground.
• If joystick (steering, directional and gear shift lever) (2)
or blade control lever (4) is touched by accident, the
work equipment may move suddenly causing a seri-
ous accident. Before leaving the operator's seat, al-
ways set parking brake lever (3) and work equipment
lock lever (5) securely in LOCK position.

1. Depress the decelerator/brake pedal (1).

2. Set joystick (steering, directional and gear shift lever) (2) to
N (NEUTRAL) position.
Position (A): FORWARD
Position (B): REVERSE
To keep the machine stopped further, depress decelerator/
brake pedal (1) until depressing effort becomes large.

3. Operate the parking brake lever (3) by holding the operat-

ing portion on the top, and place the lever in LOCK posi-
tion (L)

4. Set blade control lever (4) to LOWER position (C) and low-
er the blade to the ground.
5. Return blade control lever (4) to HOLD position (B).

3-225
Machine Operations and Controls Operation

6. Be sure to operate the work equipment lock lever (5) by

holding the operating portion on the top, then set it to
LOCK position (L).

3-226
Operation Machine Operations and Controls

How to Examine After You Complete Work

Checks Before You Stop Engine
On the machine monitor, check the engine coolant tempera-
ture, hydraulic oil temperature, engine oil pressure, remaining
fuel level, and remaining DEF level.

Checks After You Stop Engine

1. Perform walk-around check for oil or coolant leakage and for abnormality in work equipment, exterior parts,
and undercarriage.
If oil or coolant leakage or any abnormality is detected, repair it.
2. Check DEF tank, pump, injector, hose, and joint for leakage.
If any abnormality is found, ask your Komatsu distributor for repair.
3. Fill the fuel tank.
4. Check the engine compartment for paper and debris. Clean out any paper and debris to avoid a fire hazard.
5. Remove any mud affixed to the undercarriage.

3-227
Machine Operations and Controls Operation

Lock
The following sections are lockable to prevent vandalism.
Places where can be locked with the starting switch key
• Cab door opener (1) (right and left)
• Engine side cover (2) (upper left)
• Engine side cover (3) (lower left)
• Hydraulic tank inspection cover (4)
• DEF tank filler port cover (5)
• Fuel tank inspection cover (6)
• Radiator filler port inspection cover (7)
• Hydraulic tank oil filler cap (8)

Places locked with special key

• Fuel filler port cap (9)

REMARK
If padlock (A) is to be used, it is recommended to use the type
that has the cover to protect the key hole.

3-228
Operation Machine Operations and Controls

Open and Close Cap with Lock

Procedure to Open Cap with Lock
1. Insert the key into the key slot.
Make sure that you have inserted the key fully (1) before
turning it.
If the key is turned when only partially inserted, it may
break.
Position (L) : LOCK
Position (F) : OPEN
(A) : Working angle of key 180 °
(B): 45 °

2. Turn the key counterclockwise.

3. Align the rotor groove with match mark (2) of the cap.
4. Turn the cap slowly.
If a “click” is heard, the cap is unlocked and can be re-
moved.

Procedure to Lock Cap with Lock

1. Screw in the cap until it becomes tight, then insert the key into the key slot.
2. Turn the starting switch key to “LOCK” position, then remove the key.

3-229
Machine Operations and Controls Operation

How to Open and Close Fuel Filler Port Cap

Procedure to Open Fuel Tank Filler Port Cap
1. Raise lever (1) in the direction (a).
2. Turn lever (1) in direction (c) (counterclockwise) approxi-
mately 35 °.
The cap stops at the stopper, and you can open it.

Procedure to Close Fuel Tank Filler Port Cap

1. After turning lever (1) in the (c) direction (counterclock-
wise), keep it in that position and fit the cap.
2. Turn lever (1) in the (d) direction (clockwise) until it stops
at the stopper, and then tilt it in the (b) direction.

3-230
Operation Machine Operations and Controls

How to Open and Close Cover with Lock

Procedure to Open Cover with Lock
1. Insert the key into the key slot.
2. Turn the key counterclockwise and open the cover by pulling the cover handle.
• Cab door opener
Position (A): OPEN
Position (B): CLOSE (LOCK)

• Cover other than cab door opener

Position (A): OPEN
Position (B): CLOSE (LOCK)

Procedure to Lock Cover with Lock

1. Close the cover and insert the key into the key slot.
2. Turn the starting switch key to CLOSE position (B), then remove the key.

3-231
Machine Operations and Controls Operation

How to Open and Close DEF Tank Filler Port Cover

k CAUTION
• When opening or closing the DEF tank filler port cover, place the machine on a level ground, lower
the work equipment to the ground, stop the engine, and then perform the operation.
• When opening the cover, do not release the cover until it opens horizontally.
• When closing the DEF tank filler port cover, do not release the cover since it may move down by its
own weight.

Procedure to Open DEF Tank Filler Port Cover

1. Lower the work equipment to the ground on a level place, then stop the engine.
2. Insert the key into key slot (1).

3. Turn the key counterclockwise and remove it.

Position (A): OPEN
Position (B): CLOSE (LOCK)
4. Press the button (2).
Knob (3) rises and the lock is released.
5. Pull the handle (4) and open the DEF tank filler port cover.

Procedure to Lock DEF Tank Filler Port Cover

1. Close the DEF tank filler port cover.
2. Lower knob (3) to lock the cover.
3. Insert the key into key slot (1).
4. Turn the starting switch key to “CLOSE” position (B), then remove the key.
Position (A): OPEN
Position (B): CLOSE (LOCK)

3-232
Operation Handle Air Conditioner

Handle Air Conditioner

Refresh Air During Cooling
• When running the air conditioner for a long time, turn the lever to FRESH position once an hour to perform
ventilation and cooling.
• If you smoke when the air conditioner is on, the smoke may hurt your eyes. In such case, open the window
and turn the lever to FRESH for a while for ventilation and driving smoke out.
Be Careful Not to Cool Too Much
• For reasons of health, the optimum setting for cooling is considered to be that you feel slightly cool when
you enter the cab (5 to 6 °C {9 to 10.8 °F} lower than the ambient temperature).
Be careful to select the appropriate temperature.
• When outside air temperature and humidity are high, if machine is used for a long time with the grille at vent
of the front window defroster open, water drops stick to the outside surface of the glass and visibility gets
worse. In this case, close the grille or change its direction.
• If the cold air form the air conditioner blows directly against the machine monitor, water may condense on
the machine monitor screen. In that case, change the angle of the vent.

Explanation of Air Conditioner Components

(1) Air-conditioning mode selector switch (3) Temperature control switch

(2) Blower selector switch

Air Conditioner Mode Selector Switch

Air conditioner mode selector switch is used for switching the
mode of the air conditioner.
(A) Cooler
It can provide cooling. (It cannot provide heating.)
(B) Heater
It can provide heating. (It cannot provide cooling.)
(C) Dehumidification/Defrost (Air conditioner)
It can provide cooling and heating.

3-233
Handle Air Conditioner Operation

Blower Changeover Switch

Blower selector switch is used to control the air flow at cooling
and heating, and also used as a main switch.
• It changes the air flow in 4 levels of 1 (low) → 2 → 3 → 4
(high).
• If this switch is turned to OFF position, power supply is
turned off and air conditioner function stops.

Temperature Control Switch

Temperature control switch is used to adjust the temperature of
cooling and heating.
• When turning the dial counterclockwise (direction to C),
the vent temperature lowers.
• When turning the dial clockwise (direction to H), the vent
temperature rises.

How to Operate to Prevent Dust from Entering Into CAB

Raise the pressure inside of cab to a little higher than the ambient pressure in order to prevent dust from enter-
ing.
Use this method at dusty jobsite or when you want to prevent the entry of dust into the cab.
1. Close the windows and doors.
2. Set the blower selector switch to any position of 1 to 4.
Set the air conditioner mode selector switch and tempera-
ture control switch to your desired position.

3-234
Operation Handle Air Conditioner

How to Examine During Off Season

Even during the off-season, operate the air conditioner for 3 to 5 minutes once a month to maintain the oil film at
all parts of the compressor.
(Perform it in the condition that the engine is running at low idle and the temperature control switch is at center
position.)
REMARK
When the outside air temperature is low, if compressor runs at high speed suddenly, it may lead the failure of
compressor, so be careful. When the outside air temperature is 4.2 °C {39.5 °F} and below, even if the air condi-
tioner is turned on, compressor does not turn.

How to Replace Receiver

NOTICE
If the receiver is used with desiccating agent of which absorbing limit is over, the refrigerant circuit gets
clogged and may cause the failure of compressor.
Replace it every 2 years.
REMARK
The exchange interval may be shortened depending on the usage condition of receiver.
Ask your Komatsu distributor for replacement of the receiver.

3-235
Handle Radio Operation

Handle Radio
• To ensure safety, always keep the volume to a level where you can hear the outside sounds during opera-
tion.
• If water gets into the speaker case or radio, it may lead to failure. Take care not to let water get on them.
• Do not wipe the display or buttons with solvent such as benzene or thinner. Wipe with a dry soft cloth.
• When the battery disconnect switch is turned to OFF position or the power for the machine is turned off for
the replacement of the battery, the clock may be initialized. In such a case, set it again.

Explanation of Radio Equipment

(1) Power button (5) Preset button

(2) Band/AUX selector button (6) Display selector button
(3) Volume control button (7) Sound control button
(4) Tuning/time adjustment button (8) Display

Power Button
Press the power button to supply the power to the radio and the frequency is shown on display. As long as AUX
is selected, display indicates AUX on it. Press the button again to turn the power off.

Band/AUX Selector Button

Press band/AUX selector button to select the desired band or AUX.
Each time the button is pressed, the band changes FM → AM → AUX → FM...

Volume Control Button

Use the volume control button to control the volume.
Press the △ button, and the volume increases. Press the ▽ button, and the volume decreases. The range for
the volume is 0 to 32.
Hold down this button, and you can change the volume continuously.

Tuning/Time Adjustment Button

Use the tuning/time adjustment button to select frequency and step for sound adjustment and to adjust time.

3-236
Operation Handle Radio

Preset Button
If you register desired stations to the preset button beforehand, you can select each station by touching this but-
ton once.
It is possible to preset 6 stations each for both AM and FM.

Display Selector Button

Use the display selector button to change frequency and clock shown on the display.
Each time you press this button, frequency, clock and band are shown on the display in this order.
If 1.5 seconds passes while a band is shown, a frequency will be displayed.
As long as AUX is selected, this button alternately switches the display between AUX and the clock.

Sound Control Button

Press the sound control button, and the sound adjustment is ready.
Each time this button is pressed, BAL (Balance), TRE (Treble) and BAS (Bass) will be selected in this order.
If this button is pressed while BAS is displayed, the sound adjustment will be canceled.

Display
(A): Band name, “AUX”, frequency, clock and other character/
numeric information are displayed.
(B): Frequencies are displayed at steps of 50 kHz in certain
areas.
(C): Lights up when a stereo broadcasting is heard while a FM
station is selected.
(D): Lights up at the time of balance adjustment in the sound
adjusting condition.
(E): Lights up at the time of treble adjustment in the sound ad-
justing condition.
(F): Lights up at the time of bass adjustment in the sound adjusting condition.

3-237
Handle Radio Operation

AUX
NOTICE
• A stereo miniature plug can be connected.
Read the instruction manual of the equipment to connect carefully.
• As a power source for the equipment to connect, use the battery attached to that equipment.
If you use an electric power supply installed to the machine, the noise may occur.
• The noise may occur if you pull out the input plug when AUX is selected, or if you push in or pull
out the plugs of the equipment to connect.
You can hear the sound through the speaker of the machine when you connect a commercially available porta-
ble audio equipment to the machine.
1. Open cap (a).
2. Connect a portable audio equipment by using an commer-
cially available audio cable.
3. Press the band/AUX selector button and select AUX.

3-238
Operation Handle Radio

Operate Radio
Adjust Frequency
1. Press band/AUX selector button (1) and select FM or AM.
2. Press tuning/time adjustment button (2) to adjust the fre-
quency.
• Press the △ button, and the frequency increases;
press the ▽ button, and the frequency decreases.
• Hold down the △ button, and the frequency increases
continuously; hold down the ▽ button, and the fre-
quency decreases continuously.
• Hold down the △ button and release it, then the fre-
quency increases continuously. Hold down the ▽ but-
ton and release it, them the frequency decreases continuously as an auto seek.
When a proper frequency is picked up, the tuning automatically stops.

How to Adjust Frequency (Auto Presetting)

1. Press band/AUX selector button (1) and select FM or AM.
2. Hold down sound control button (2).

When a proper frequency is picked up, it is automatically registered to preset memories 1 to 6.

Load Preset
1. Press band/AUX selector button (1) and select FM or AM.
2. Press one of 1 to 6 of preset button (2).

The frequency registered in the preset number of the pressed button is called up and received.
“Example”
While a frequency is displayed, press button 1 of preset button (2), and the preset number “P-1” appears on the
display.
The preset number is shown for 0.5 seconds, and then the frequency is displayed.

3-239
Handle Radio Operation

Preset Station
Hold down one of 1 to 6 of preset button (1) while listening to
the radio.

The currently received frequency is registered to the preset number corresponding to the pressed button.
“Example”
While a frequency is displayed, keep pressing button 1 of preset button (1), and the preset number “P-1” is dis-
played.
After the preset number flashes 3 times, the frequency is displayed and then registered to preset number “P-1”.

How to Adjust Sound Balance

1. Press sound control button (1) to light up “BAL” on the dis-
play.
You can adjust the sound (balance).
2. Press tuning/time adjustment button (2) to adjust the
sound (balance).
• Press the △ button, and the speaker output on the R
side increases by 1. (R1 to R7)
• Press the ▽ button, and the speaker output on the L
side increases by 1. (L1 to L7)

High Register Range (Treble) Setting

1. Press sound control button (1) to light up “TRE” on the dis-
play.
You can adjust the high register range (treble) of the
sound.
2. Press tuning/time adjustment button (2) to adjust the high
register range (treble).
• Press the △ button, and the high register range (tre-
ble) level increases by 1. (Maximum + 7)
• Press the ▽ button, and the high register range (tre-
ble) level decreases by 1. (Minimum - 7)

3-240
Operation Handle Radio

Low Register Range (Bass) Setting

1. Press sound control button (1) to light up “BAS” on the dis-
play.
You can adjust the low register range (bass) of the sound.
2. Press tuning/time adjustment button (2) to adjust the low
register range (bass).
• Press the △ button, and the low register range (bass)
level increases by 1. (Maximum + 7)
• Press the ▽ button, and the low register range (bass)
level decreases by 1. (Minimum - 7)

How to Adjust Clock

1. Press display selector button (1) to display the clock.
2. Hold down display selector button (1) to flash the “HOUR”
display portion.
You can adjust the hour.
3. Press tuning/time adjustment button (2) to adjust the hour.
• If you press △ button, “HOUR” display increases by 1.
• If you press ▽ button, “HOUR” display decreases by
1.
4. Press display selector button (1) to flash the “MINUTE” dis-
play portion.
You can adjust the minute.
5. Press tuning/time adjustment button (2) to adjust the minute.
• If you press △ button, “MINUTE” display increases by 1.
• If you press ▽ button, “MINUTE” display decreases by 1.
6. Press display selector button (1) to cancel time adjustment.
The screen returns to clock display.

Antenna
NOTICE
When transporting the machine or when parking it in a garage, direct the antenna down and make sure
that it does not contact anything.

3-241
Transportation Operation

Transportation
Travel on Road
When traveling on paved roads, use flat shoes to protect their surface.
If the flat track shoes cannot be prepared, always place boards to protect the road surface even when traveling
a short distance.
Note that the asphalt road becomes soft in summer.

Precautions When You Transport Machine

When transporting the machine, observe all related laws and regulations, and be careful to assure safety.

Transportation
When transporting the machine, choose the transportation method in reference to the weight and dimensions of
machine.
Note that the machine “SPECIFICATIONS” (weight and dimensions) vary depending on the kind of track shoes,
blade, or other equipment.

Remove CAB
Operator's seat and control levers are made in one unit with the cab. If cab is removed, machine cannot be op-
erated.
If you have any trouble in transportation, consult your Komatsu distributor.

Remove Work Equipment

Overall width can be shortened by angling the blade fully. Re-
ferring to the figure, decide whether the blade should be re-
moved for transportation.
Normal Angling maximum angle
A (mm {ft B (mm{ft
C (deg.)
{in} }) {in} })
Narrow 3045 {10’0”} 2725 {8’11”}
D51EX
Wide 3350 {11’0”} 2990 {9’10”}
Wide 2990 {9’10”} 29
D51PX High ca- 3350 {11’0”}
2995 {9’10”}
pacity

1. Lower the blade to the ground and set it in parallel with the
ground surface.
2. Remove the work equipment assembly.
When removing the work equipment, ask your Komatsu
distributor to perform the work.

3-242
Operation Transportation

Load onto and Unload from a Trailer

k WARNING
• Since loading and unloading of the machine is dangerous, be extremely careful.
• When loading or unloading the machine, lower the engine speed, set the speed range to the 1st, and
operate slowly.
• Use ramps with ample width, length, thickness, and strength and install them with a maximum slope
of 15°.
If the ramps deflect much, reinforce them with blocks, etc.
• Load the machine on a flat and firm ground.
Secure sufficient distance from the road edge.
• Remove mud, etc. from the undercarriage of the machine so that the machine does not slip side-
ways on the ramps.
In addition, remove water, snow, ice, grease, oil, etc. from the ramps.
• Never correct your steering on the ramps. There is danger that the machine may tip over.
If necessary, drive off the ramps or back on to the trailer and correct the direction.
• The center of gravity of the machine shifts suddenly at the joint between the ramps and the trailer,
and it is dangerous that the machine loses its balance. Pass slowly.

When loading or unloading the machine, be sure to use ramps or platform, and follow the procedure shown be-
low.

Procedures to Load Machine

Load on a firm and level ground.
1. Park a trailer on a firm and level ground.
Maintain a safe distance from the road shoulder
2. Apply the brake of the trailer securely.
3. Set chocks (1) to the tires to secure the trailer.
4. Install ramps (2).
Set gap (3) between ramps (2) to match the distance be-
tween the right and left tracks, and keep angle (4) to a
maximum of 15 °.
If ramps (2) bend appreciably under the weight of the ma-
chine, put wooden block (5) under the ramps to support
them.
5. Start the engine.
6. When transporting the machine with the work equipment installed to it, raise the work equipment.
1) Be sure to operate the lock lever by holding the oper-
ating portion on the top, then set it to FREE position
(F).
2) Operate the blade control lever and raise the work
equipment.

3-243
Transportation Operation

7. Operate the parking brake lever by holding the operating

portion on the top, and place the lever in FREE position (F)
8. Set the speed range to 1st or less in variable mode.
9. Set the travel direction toward the ramps and drive slowly.
The center of gravity of the machine shifts suddenly at the
joint between the ramps and the trailer, and the machine is
unbalanced and becomes unstable. Drive the machine
carefully and slowly.
10. Place the machine at the specified position on the trailer.

How to Secure Machine

k WARNING
If the end of blade is out of the trailer, angle the blade.

NOTICE
Be sure to lower the car radio antenna to the stow position.
After loading the machine onto a trailer, secure the machine as follows.
1. Lower the work equipment slowly.
(When transporting with work equipment installed)
2. Operate the work equipment lock lever by holding the op-
erating portion on the top, and place the lever in LOCK po-
sition (L) securely.

3. Operate the parking brake lever by holding the operating

portion on the top, and place the lever in LOCK position (L)
securely.
4. Stop the engine, and remove the key from the starting
switch.
5. Securely lock the glass window, cab door, engine side cov-
er, hydraulic tank inspection cover, DEF tank filler port cov-
er, and fuel tank inspection cover.
6. Put wooden blocks (1) to the front and rear of the R.H. and
L.H. tracks.
7. Fix the machine securely with chains or wire ropes of appropriate strength with method (A) or (B).
Secure the machine so that it will not move during transportation.
In particular, fix the machine securely to prevent it from slipping sideways.

3-244
Operation Transportation

• (A): Wind chains or wire ropes around the track shoe.

• (B): Pass chains or wire ropes through the holes of

track links.

8. Place wire rope protection pads on the corners of the machine.

Procedures to Unload Machine

Perform unloading of the machine on a firm and level ground.
1. Park a trailer on a firm and level ground.
Maintain a safe distance from the road shoulder
2. Apply the brake of the trailer securely.
3. Set chocks (1) to the tires to secure the trailer.
4. Install ramps (2).
Set gap (3) between ramps (2) to match the distance be-
tween the right and left tracks, and keep angle (4) to a
maximum of 15 °.
If ramps (2) bend appreciably under the weight of the ma-
chine, put wooden block (5) under the ramps to support
them.
5. Remove the chains and wire ropes fastening the machine.
6. Start the engine.
7. When transporting the machine with the work equipment installed to it, raise the work equipment.
1) Be sure to operate the lock lever by holding the oper-
ating portion on the top, then set it to FREE position
(F).
2) Operate the blade control lever and raise the work
equipment.

3-245
Transportation Operation

8. Operate the parking brake lever by holding the operating

portion on the top, and place the lever in FREE position (F)
9. Set the speed range to 1st or less in variable mode.
10. Set the travel direction toward the ramps and drive slowly.
The center of gravity of the machine shifts suddenly at the
joint between the ramps and the trailer, and the machine is
unbalanced and becomes unstable. Drive the machine
carefully and slowly.
Drive down the ramps slowly and carefully until the ma-
chine leaves the ramps perfectly.

How to Lift Machine

k WARNING
• The person using the crane to perform lifting operations must be a qualified crane operator.
• Never perform lifting operation if any person is on the machine being lifted.
• Always use a wire rope that has ample strength for the weight of the machine being lifted.
• Keep the machine horizontal while lifting it.
• When performing lifting operations, place the work equipment lock lever and parking brake lever in
LOCK position to prevent the machine or work equipment from moving unexpectedly.
• Never enter the area under or around a lifted machine.
• There is a danger that the machine loses its balance.
Use the procedure below to set the machine in the proper posture and use the lifting equipment
when lifting the machine.

NOTICE
This lifting method applies to the standard specification machine.
The method of lifting differs depending on the attachments and options installed.
For details of the procedure for machines that are not the standard specification, consult your Komatsu
distributor.
When lifting the machine, stop it on a level place, then lift it as follows.
1. Operate the parking brake lever by holding the operating
portion on the top, and place the lever in LOCK position (L)
securely.

3-246
Operation Transportation

2. Operate the work equipment lock lever by holding the op-

erating portion on the top, and place the lever in LOCK po-
sition (L) securely.
3. Stop the engine, and remove the key from the starting
switch.
4. Securely lock the glass window, cab door, engine side cov-
er, hydraulic tank inspection cover, DEF tank filler port cov-
er, and fuel tank inspection cover.

5. Select the lifting tool such as wire ropes and slings match-
ing to the weight of the machine, and fit the wire ropes to
the slinging position.
(A) Mark indicating slinging position
NOTICE
• Use protectors, etc. so that the wire ropes will not
be broken at sharp edges or narrow places.
• When using a spreader beam, select an ample
width to prevent contact with the machine.
6. Just before slinging the machine, lift it off the ground by
100 to 200 mm {3.9 to 7.9 in} while it is being set.
7. Check that the wire ropes are free of looseness and the
machine is kept on a level state.
8. Sling the machine slowly.

3-247
Cold Weather Operation Operation

Cold Weather Operation

Cold Weather Operation Information
If the ambient temperature becomes low, it becomes difficult to start the engine, and the coolant may freeze.
Follow the instructions described as follows.

Fuel and Lubricants

Change fuel and oil with ones of low viscosity for all components.
For the specified viscosity, see “How to Use Fuel, Coolant and Lubricants by Ambient Temperature”.

Coolant
k WARNING
• Coolant is toxic. Be careful not to get it into your eyes or on your skin.If it should get into your eyes
or on your skin, wash it off with large amounts of fresh water and see a doctor immediately.
• When handling the cooling water containing coolant that has been drained during changing the
coolant or repair of radiator, contact your Komatsu distributor or request a qualified company to
perform the operation. Coolant is toxic, so never pour it into drainage ditches or drain it onto the
ground surface.

NOTICE
Komatsu recommends using Non-Amine Engine Coolant (AF-NAC) for the coolant.
Non-Amine Engine Coolant (AF-NAC) is already diluted with distilled water, so it is not flammable.
For the concentration of Non-Amine Engine Coolant (AF-NAC), see “How to Use Fuel, Coolant and Lubricants
by Ambient Temperature”.

DEF
NOTICE
• DEF freezes at –11 °C {12.2 °F} .
If DEF in DEF tank freezes, it may expand and the devices in the tank may be broken or the parts
may be affected. Add DEF to the specified amount for cold weather (below the level of when DEF
may freeze).
• If DEF or the machine equipped with DEF system cannot be stored at the outside temperature is
lower than –11 °C {12.2 °F} , DEF in the tank may freeze. Ask your Komatsu distributor for discharg-
ing of DEF, and keep it in the condition free from freezing.

3-248
Operation Cold Weather Operation

Battery
k WARNING
• Do not bring any open flame near the battery. Otherwise, it may explode since the battery generates
the flammable gas.
• Battery electrolyte is dangerous object. If it gets in your eyes or on your skin, wash it off with a
large amount of water and consult a doctor.
• Battery electrolyte dissolves paint. If it gets on the bodywork, wash it off immediately with water.
• Do not charge the battery or start the engine with a different power source if the battery electrolyte
is frozen. Battery may explode.
• Battery electrolyte is toxic. Do not let it flow into drainage ditches or spray it on to the ground sur-
face.

When the ambient temperature drops, the capacity of the battery will also drop. Maintain the battery charging
rate as close as possible to 100%. Insulate it against cold temperature to ensure that the machine can be star-
ted easily in the next morning.
REMARK
Measure the gravity of the electrolyte and calculate the charging rate from the following conversion table.
Electrolyte Temperature (℃) {℉}
20 {68} 0 {32} -10 {14} -20 {-4}
Charging Rate (%)
100 1.28 1.29 1.30 1.31
90 1.26 1.27 1.28 1.29
80 1.24 1.25 1.26 1.27
75 1.23 1.24 1.25 1.26

• When the ambient temperature is low, the capacity of the battery considerably drops. Cover it, or remove it
from the machine to place it in the warm place. Restore it again before the operation.
• If the electrolyte level is low, add distilled water in the morning before beginning the work. Do not add water
after the day's work to prevent diluted electrolyte in the battery from freezing during the night.

3-249
Cold Weather Operation Operation

Precautions After Daily Work Ends in Cold Weather

k WARNING
Performing idling of the tracks is dangerous, stay well away from the tracks.

To prevent mud, water, or the undercarriage from freezing and making it impossible for the machine to move on
the following morning, observe the following precautions.
• Remove all the mud and water from the machine body. In particular, wipe the hydraulic cylinder rods clean
to prevent damage to the seal caused by mud, dirt, or drops of water on the rod from getting inside the seal.
• Place the machine on a firm, dry ground.
If this is impossible, park the machine on boards.
The boards prevent the tracks from freezing to the ground, and allow the machine to move the next morn-
ing.
• Open the drain valve and drain any water collected in the fuel system to prevent it from freezing.
• Fill up the fuel tank. This minimizes moisture condensation in the tank when the temperature drops.
• In cold weather condition, add DEF to the defined level strictly. If adding more than the defined level, it may
expand to break the devices in the tank when it freezes.
If DEF tank level is lower than the defined level for the cold weather, DEF may freeze easily to damage the
parts in DEF system. If the filler cap freezes, defreeze and open.
• After operation in water or mud, remove water from undercarriage as described below to extend undercar-
riage service life.
• Do not leave the machine running idle for a long time. The inside of KCCV and blowby piping may freeze
solid and block the piping.
To prevent freeze, stop the engine or, if it is necessary to run the engine at idle, apply the load from time to
time.
• Do not continue low-load operation . If continuous low-load operation is performed, operate the machine
with load (warm-up operation) before stop the engine.

After Cold Weather Season

When the season changes and the weather becomes warmer, do as follows.
Replace the fuel and oil for all equipment with the ones of the specified viscosity. For details, see “How to Use
Fuel, Coolant and Lubricants by Ambient Temperature”.
If the machine is parked for long time in the cold weather condition, quality of DEF may be affected by repeated
freeze, ask your Komatsu distributor to inspect.

3-250
Operation Precautions for Long-Term Storage

Precautions for Long-Term Storage

Prepare for Long-Term Storage
When putting the machine in long-term storage (more than one month), store it as follows.
• Clean and wash all parts of the machine and store it indoors. If the machine has to be stored outdoors,
place it on a level ground and cover it with tarpaulins.
• Fill up the fuel tank. This prevents dew condensation.
• Grease the machine and change the oil before storage.
• Fill up DEF tank (Except cold weather condition). Urea deposits caused by internal drying can be preven-
ted. Urea deposits may cause failures in component operation.
When storing the machine in a place where the temperature is lower than –11 °C (12.2 °F), however, add
DEF to the specified amount for cold weather (below the level of when DEF may freeze).
• Apply thin film of grease to metal surface of the hydraulic piston rods and the idler adjusting rods.
• As for the battery, turn the starting switch to OFF position, check that the system operating lamp goes out,
turn the battery disconnect switch key to OFF position, and pull it out and keep it with covered condition.
• Place all control levers in NEUTRAL position, place the work equipment lock lever and parking brake lever
in LOCK position, and set the fuel control dial to Low idle (MIN) position.
• To prevent rust, fill the cooling circuit with Non-Amine Engine Coolant (AF-NAC) to give a density of at least
30 % for the engine coolant.

Maintenance During Long-Term Storage

k WARNING
If it is necessary to perform the rust-prevention operation while the machine is indoors, open the doors
and windows to improve ventilation and prevent gas poisoning.

• During storage, operate and move the machine for a short distance once a month so that a new film of oil
will coat moving parts. At the same time, charge the battery as well.
• When operating the work equipment, wipe off all the grease from the hydraulic cylinder rods.
• If the machine is equipped with an air conditioner, operate the air conditioner for 3 to 5 minutes once a
month to lubricate all parts of the air conditioner compressor. Always run the engine at low idle when doing
this. In addition, check the refrigerant level twice a year.

3-251
Precautions for Long-Term Storage Operation

Start Machine After Long-Term Storage

NOTICE
If the machine has been stored without performing the monthly rust-prevention operation, consult your
Komatsu distributor before using it.
When using the machine after long-term storage, perform the following items before using it.
• Wipe off the grease from the hydraulic cylinder rods.
• Add oil and grease at all lubrication points.
• When the machine is stored for a long period, moisture in the air will mix with the oil. Check the oil before
and after starting the engine. If there is water in the oil, change all the oil.
• Insert the battery disconnect switch key and turn it to ON position.
• If the machine is stored for a long period with the battery disconnect switch OFF or the battery terminal dis-
connected, the clock information and radio tuning information may be lost. In this case, set the information
again. For detail, see “Clock Adjustment” and “HANDLE RADIO”.
• When starting the engine, perform the engine warm-up operation thoroughly.
If the machine has been stored for more than 2 months, perform the following procedure.
• Before starting the engine, replace DEF filter and fill up DEF tank according to the procedure in “METHOD
FOR REPLACING DEF FILTER”.
• Start the engine and check correctly.
If SCR system has any abnormality, warning is displayed on the monitor screen and the audible alert
sounds. If SCR system has any abnormality, stop the engine, and then start it again.
If SCR system still has abnormality after the engine is restarted, contact your Komatsu distributor.
• If DEF is kept in DEF tank for more than 1 year, ask your Komatsu distributor for replacement.
Dispose of drained DEF according to the local regulations and rules.
Aged DEF may have smell of ammonia. Replace DEF in a well-ventilated place and take care not to inhale
its vapor.

3-252
Operation Troubles and Procedures

Troubles and Procedures

Precautions When You Tow Machine
k WARNING
Always use the correct towing equipment and towing
method. Any mistake in the selection of the wire rope or
drawbar or the method of towing a disabled machine and
being towed may lead to serious personal injury or death.
• If the engine does not start, block the tracks from
movement, then release the brake. If blocks are not
used, there is a danger that the machine may move
suddenly.
• Make sure that the towing wire rope has the strength
at least 1.5 times the working weight of the machine to
be towed.
• Never use the wire rope which has cut strands (A), re-
duced diameter (B), or kinks (C). There is a danger that
the rope may break during the towing operation.
• Always wear leather gloves when handling the wire
rope.
• Never tow a machine on a slope.
• During the towing operation, never stand between the
towing machine and the towed machine.
• Move the machine slowly.
Do not apply a sudden load to the wire rope.

NOTICE
The allowable towing load of this machine is 83300 N {8490 kgf}.
Do not tow any load greater than this.
Connect a wire rope to the part indicated with the arrow in the
drawing.

When you use wire rope, chain, or link for the towing work,
wind it around the equalizer bar.
Do not tow the machine with the force 1.5 times or more of the
working weight in this case.
For details of the method of towing, contact your Komatsu dis-
tributor.
• If the engine stops or the oil pressure in the brake circuit
lowers because of a trouble in the hydraulic system, the
brake works and the machine cannot move. To move the G0159439
machine in this case, the oil pressure in the brake circuit

3-253
Troubles and Procedures Operation

must be heightened to the specified level with a special device. Contact your Komatsu distributor.
• Moving a machine by towing is only used to move it to a place where it is possible to perform inspection
and maintenance.
Do not tow it a long distance.
• If it is impossible to operate the steering and brakes of the machine being towed, do not let anyone ride on
the machine.
• Keep the angle of the towing line to the minimum. Operate the machine so that the angle does not become
greater than 10 ° from the straight travel direction.

3-254
Operation Troubles and Procedures

Precautions for Discharged Battery

k WARNING
• It is dangerous to charge a battery when installed on a
machine. Make sure that it is removed before charg-
ing.
• When checking or handling the battery, stop the en-
gine and turn the starting switch and battery discon-
nect switch keys to OFF positions.
• The battery generates hydrogen gas, and it is danger-
ous that it may explode. Do not bring lighted ciga-
rettes near the battery, or do nothing that will cause
sparks.
• Battery electrolyte is dilute sulfuric acid, and it will at-
tack your clothes and skin. If it gets on your clothes or
on your skin, immediately wash it off with a large
amount of clean water.
If it gets in your eyes, wash the eyes immediately with
clean water, then consult a doctor for medical treat-
ment.
• When handling batteries, always wear protective eye-
glasses and rubber gloves.
• When removing the battery, first disconnect the cable
from the ground (normally the negative (-) terminal).
When installing, first connect the cable to the positive
(+) terminal.
If a tool touches the positive terminal and the chassis,
it is dangerous that it may cause a spark. Be extremely
careful.
• If the terminals are loose, it is dangerous that the de-
fective contact may generate sparks, and it may cause
an explosion.
Install the cable terminals securely.
• When removing or installing the cable terminals,
check which is the positive (+) terminal and which is
the negative (-) terminal.

3-255
Troubles and Procedures Operation

Remove and Install Battery

k WARNING
Stop the engine, and turn the starting switch and the battery disconnect switch keys to OFF positions
when handling the battery.

Prepare the wooden blocks.

1. Open the hydraulic tank inspection cover (1).

2. Turn the battery disconnect switch to OFF position (O).

3. Remove the cap (2) of the reservoir tank.

4. Remove the bolts (3) (3 pieces) and remove the reservoir

tank (4).

3-256
Operation Troubles and Procedures

5. Remove the wing bolts (5) (2 pieces) and remove the vinyl
cover (6).
6. Remove the bolts (7) (2 pieces) and remove the grease
gun holder (8).

7. Remove the bolts (9) (2 pieces) and remove the clip.

8. Loosen the nuts of terminal (10) (2 places) and disconnect
the cable from the battery.
Disconnect the ground cable (normally connected to the
negative (-) terminal) first.
If any tool touches between the positive (+) terminal and
the chassis, there is a hazard of sparks being generated.

9. Remove the nuts (12) and (13) (2 places each) of the bat-
tery mounting fixture (11), and remove the rods (14) (2 pla-
ces).

10. Remove the bolts (15) (2 pieces), and remove the bracket
(16).

11. Take out the battery (17).

When taking out the battery, move it toward the rear of the
machine.

3-257
Troubles and Procedures Operation

12. Remove the bolts (18) (2 pieces), and remove the bracket
(19).
13. Loosen the nuts of terminal (20) (2 places) and disconnect
the cable from the battery.
Disconnect the ground cable (normally connected to the
negative (-) terminal) first.
If any tool touches between the positive (+) terminal and
the chassis, there is a hazard of sparks being generated.
14. Remove the nuts (22) and (23) (2 places each) of the bat-
tery mounting fixture (21), and remove the rods (24).
15. Remove the bolts (25) (3 pieces), and remove the bracket
(26).
16. Put down the wooden blocks (27), and take out the battery
(28) while pulling it out.
When taking out the battery, move it toward the rear of the
machine.
17. Replace the battery.
18. After replacing the battery, secure it according to the fol-
lowing procedure.
1) Restore the battery (28) to the original position, and
install the bracket (26) with bolts (25) (3 pieces).
2) Tighten the nut (22) of the battery mounting fixture (21) evenly into the right and left rods (24) by hand.
3) Tighten the nut (22).
Tightening torque: 1.96 to 2.94 Nm {0.2 to 0.3 kgfm, 1.45 to 2.17 lbft}
4) Tighten the nut (23) by hand until it touches the face of nut (22).
5) Hold the nut (22) with a wrench, and tighten the nut (23).
Tightening torque: 11.8 to 19.6 Nm {1.2 to 2.0 kgfm, 8.68 to 14.5 lbft}
6) Restore the battery (17) to the original position, and install the bracket (16) with bolts (15) (2 pieces).
7) Tighten the nut (12) of the battery mounting fixture (11) evenly into the right and left rods by hand.
8) Tighten the nut (12).
Tightening torque: 1.96 to 2.94 Nm {0.2 to 0.3 kgfm, 1.45 to 2.17 lbft}
9) Tighten the nut (13) by hand until it touches the face of nut (12).
10) Hold the nut (12) with a wrench, and tighten the nut (13).
Tightening torque: 11.8 to 19.6 Nm {1.2 to 2.0 kgfm, 8.68 to 14.5 lbft}
19. Insert the terminal hole into the battery and tighten the nut.
When installing the battery, connect the ground cable last.
Tightening torque: 9.8 to 11.8 Nm {1.0 to 1.2 kgfm, 7.23 to 8.68 lbft}
20. Install the parts which have been removed in steps 3 to 7.
21. Turn the battery disconnect switch to ON position (I).
22. Close the hydraulic tank inspection cover (1).

3-258
Operation Troubles and Procedures

Precautions When You Charge Battery

k WARNING
When charging the battery, if the battery is not handled
correctly, there is a danger that the battery may explode.
Follow the instruction manual accompanying the battery
charger, and observe the following.
• Set the voltage of the charger to match the voltage of
the battery to be charged. If the correct voltage is not
selected, the charger may overheat and cause an ex-
,&
plosion.
• Connect the positive (+) charger clip of the charger to
the positive (+) terminal of the battery, then connect
the negative (-) charger clip of the charger to the nega-
tive (-) terminal of the battery. Be sure to attach the
clips securely.
• Set the charging current to 1/10 of the value of the rat-
ed battery capacity; when performing rapid charging,
set it to less than the rated battery capacity.
If the charger current is too high, the electrolyte will
leak or the battery cells will dry up, and this may cause
the battery to catch fire and explode.
• If the battery electrolyte is frozen, do not charge the
battery or start the engine with a different power
source. It is dangerous that this may ignite the battery
electrolyte and cause the battery to explode.
• Do not use or charge the battery if the battery electro-
lyte level is below LOWER LEVEL line. This may cause
an explosion. Check the battery electrolyte level peri-
odically and add distilled water to bring the electrolyte
level to UPPER LEVEL line.

3-259
Troubles and Procedures Operation

Start Engine with Jumper Cables

k WARNING
• When connecting the cables, never contact the posi-
tive (+) and negative (-) terminals.
• Always wear protective eyeglasses and rubber gloves
when starting the engine by using the jumper cable.
• Be careful not to let the normal machine and failed ma-
chine contact each other.
The sparks caused near the battery could ignite the
hydrogen gas generated from the battery, so be care-
ful not to let it happen.
• Make sure that there is no mistake in the jumper cable
connections. When the final cable is connected to the
engine block of the failed machine, sparks are gener-
ated. Accordingly, connect it to a point as far from the
battery as possible.
• When disconnecting the jumper cable, take care not to
bring the clips in contact with each other or with the
machine.

NOTICE
• The starting system for this machine uses 24 V. Accordingly, the normal machine must be equipped
with a 24 V power supply.
• The sizes of the jumper cables and clips should be suitable for the battery size.
• The battery of the normal machine must be the same capacity as that of the failed machine.
• Check the cables and clips for damage or corrosion.
• Make sure that the cables and clips are firmly connected.
• Check that the work equipment lock levers and parking brake levers of both machines are in LOCK
position.
• Check that each lever is in NEUTRAL position.
• To prevent damage of the electric devices of the failed machine, turn the starting switch of the failed
machine OFF, check that the system operating lamp is not lit, and then turn the battery disconnect
switch key to OFF position before connecting the jumper cable.

3-260
Operation Troubles and Procedures

Procedure to Connect Jumper Cables

Turn the starting switch and battery disconnect switch of the failed machine, and the starting switch of the nor-
mal machine to OFF position.
1. Connect the clip of jumper cable (A) to the positive (+) ter-
minal of battery (C) on the failed machine.
2. Connect the clip at the other end of jumper cable (A) to the
positive (+) terminal of battery (D) on the normal machine.
3. Connect the clip of jumper cable (B) to the negative (-) ter-
minal of battery (D) on the normal machine.
4. Turn the battery disconnect switch (S) of the failed ma-
chine to ON position.
5. Connect the clip at the other end of jumper cable (B) to en-
gine cylinder block (E) of the failed machine.

How to Start Engine

1. Check both of normal machine and failed machine that the lock lever is set to LOCK position.
2. Check both of normal machine and failed machine that the control levers are in NEUTRAL position.
3. Make sure the clips are firmly connected to the battery terminals.
4. Start the engine of the normal machine and run it at high idle (Max. speed).
5. Turn the starting switch of the failed machine to START position and start the engine.
If the engine does not start at first, try again after 2 minutes or more.

Procedure to Disconnect Jumper Cables

After the engine has started, disconnect the jumper cables in the reverse of the order in which they were con-
nected.
1. Remove the clip of jumper cable (B) from engine cylinder
block (E) on the failed machine.
2. Remove the clip of jumper cable (B) from the negative (-)
terminal of battery (D) on the normal machine.
3. Remove the clip of jumper cable (A) from the positive (+)
terminal of battery (D) on the normal machine.
4. Remove the clip of jumper cable (A) from the positive (+)
terminal of battery (C) on the failed machine.

3-261
Troubles and Procedures Operation

Other Trouble
Troubles and Procedures on Electrical System
• Contact your Komatsu distributor for the remedies indicated with (*) in the remedy column.
• Ask your Komatsu distributor for repairs for problems or causes which are not listed below.
Problem Main causes Remedy
Lamp does not glow brightly even Defective wiring Check and repair loose terminals,
when the engine runs at high speeds. open circuit. (*)
Incorrect adjustment of belt tension Adjust alternator drive belt tension.
See EVERY 1000 HOURS MAINTE-
NANCE.
Lamp flickers while engine is running. Defective wiring Check and repair loose terminals,
open circuit. (*)
Incorrect adjustment of belt tension Adjust alternator drive belt tension.
See EVERY 1000 HOURS MAINTE-
NANCE.
Charge level caution lamp does not Defective alternator Replace. (*)
go out even when engine is running.
Defective wiring Check, repair. (*)
Unusual noise is generated from al- Defective alternator Replace. (*)
ternator
Starting motor does not rotate even Defective wiring Check, repair. (*)
when starting switch is turned to
Insufficient battery charge Charge the battery.
START position.
Battery disconnect switch is at OFF Turn it to ON position.
position.
Engine shutdown secondary switch is Set it “NORMAL” position.
at “ENGINE STOP” position
Incorrect adjustment of safety switch Adjust safety switch. (*)
Pinion of starting motor repeats en- Insufficient battery charge Charge the battery.
gaging and disengaging (rattles).
Starting motor incapable of cranking Insufficient battery charge Charge the battery.
engine smoothly.
Defective starting motor Replace. (*)
Starting motor disengages before en- Defective wiring Check, repair. (*)
gine starts.
Insufficient battery charge Charge the battery.
Automatic preheating does not work. Defective wiring Check, repair. (*)
Defective heater relay Replace. (*)
Defective engine controller Check, replace. (*)
Preheating pilot lamp does not light Defective wiring Check, repair. (*)
up.
Defective heater relay Replace. (*)
(When engine coolant temperature is
-3 °C {27 °F} or below.) Defective monitor Replace. (*)

Oil pressure caution lamp does not Defective monitor Replace. (*)
light up even when engine is stop-
Defective caution lamp switch Replace. (*)
ped.
(Starting switch is at ON position.)

3-262
Operation Troubles and Procedures

Problem Main causes Remedy

Charge level caution lamp does not Defective monitor Replace. (*)
light up when engine is stopped.
Defective wiring Check, repair. (*)
(Starting switch is at ON position.)
Outside of electrical heater is not Defective wiring Check, repair. (*)
warm when touched by hand.
Wire breakage in electrical intake air Replace. (*)
heater
Malfunction of heater relay Check, repair heater relay. (*)
Malfunction of air conditioner Blown fuse Check, repair. (*)
Insufficient battery charge Charge the battery.
Defective air conditioner switch Replace air conditioner switch. (*)
Defective blower switch Replace blower switch. (*)
Defective compressor Replace. (*)
Engine does not start. Damaged data in the controller Check, repair. (*)
(L04 lights up on monitor.) Other system troubles Check, repair. (*)

3-263
Troubles and Procedures Operation

Troubles and Procedures on Chassis

• Contact your Komatsu distributor for the remedies indicated with (*) in the remedy column.
• Ask your Komatsu distributor for repairs for problems or causes which are not listed below.
Problem Main causes Remedy
Machine does not stop even if the de- Incorrect adjustment of decelerator/
Adjust, check, repair. (*)
celerator/brake pedal is depressed. brake pedal sensor and switch
Track shoe comes off. Track tension is too loose. Adjust the track tension. See WHEN
REQUIRED.
Abnormal wear of sprocket Track shoe is too low, or too high. Adjust track tension. See WHEN RE-
QUIRED.
Blade rises slowly or do not rise. Lack of hydraulic oil Add oil to the specified level. See
CHECKS BEFORE STARTING.
Work equipment lock lever is in Set to FREE.
LOCK position.
Charge pump is worn or scuffed. Check, replace. (*)
Defective work equipment EPC valve Check, replace. (*)
When machine is steered, it does not Parking lever is in LOCK position. Set to FREE.
turn.
Defective lever wiring Check, repair. (*)
Abnormal noise is heard from idler. Lack of idler oil Adjust track tension. See WHEN RE-
QUIRED.
Add oil to the specified level. (*)
Lack of traction force (Travel speed is Lack of engine power See “Troubles and Procedures on
low.) Engine”
Acceleration of travel speed is low. Hydraulic oil temperature is low. Warm-up.
Even if the joystick (steering, direc- Parking lever is in LOCK position. Set to FREE.
tional and gear shift lever) is operat-
Charge pump is worn or scuffed. Check, replace. (*)
ed, machine does not move off.
Brake release solenoid does not op- Check, repair, replace. (*)
erate.
Defective joystick (steering, direction- Check, replace. (*)
al and gear shift lever)
Fan is set in reverse mode. Set it to normal rotation mode.
Turbo protect function in operation Wait until operation finishes.
Only one side of track shoe moves. HST pump is defective. Check, replace. (*)
Electrical system is defective. Check, repair, replace. (*)
Machine deviates without steering Defective joystick (steering, direction- Adjust, check, repair. (*)
operation. al and gear shift lever)
Defective HST pump and motor Adjust, check, repair, replace. (*)
Defective motor speed sensor Adjust, check, replace. (*)
Hydraulic oil temperature is low. Warm-up.
Air is mixed in hydraulic circuit. Bleed air. (*)

3-264
Operation Troubles and Procedures

Problem Main causes Remedy

Hydraulic oil gets overheat. (Pointer Work load is too large. Lighten the work load to prevent trav-
is in red range.) el relief.
Work equipment is relieved. Avoid operating the blade to the
stroke end of cylinder.
Continuous high-speed travel Drive in lower speed range.
Clogged oil cooler fins or damaged Clean or repair. See WHEN RE-
fin QUIRED.

3-265
Troubles and Procedures Operation

Troubles and Procedures on Engine

• Contact your Komatsu distributor for the remedies indicated with (*) in the remedy column.
• Ask your Komatsu distributor for repairs for problems or causes which are not listed below.
Problem Main causes Remedy
After warming up, when engine Insufficient oil in engine oil pan (suck- Add oil to specified level. See
speed is increased, engine oil pres- ing in air) CHECKS BEFORE STARTING.
sure caution lamp still lights up.
Improper oil is used. (Viscosity is im- Referring to “Recommended Fuel,
proper.) Coolant, and Lubricant”, replace oil
with proper one.
Clogged oil filter cartridge Replace. See EVERY 500 HOURS
MAINTENANCE.
Oil leakage due to defective tighten- Check and repair. (*)
ing or breakage of oil pipe or pipe
joint.
Defective monitor Replace. (*)
Steam spurts out from top of radiator. Lowered coolant level, leakage of Check, add coolant, repair by refer-
(pressure valve) coolant ring to CHECKS BEFORE START-
ING.
Dirt or scale accumulated in cooling Change coolant, flush inside of cool-
system ing system by referring to WHEN RE-
QUIRED.
Clogged radiator fins or damaged fin Clean or repair. See WHEN RE-
QUIRED.
Defective thermostat Replace thermostat. (*)
Loose radiator filler cap (in high alti- Tighten the cap or replace packing.
tude operation)
Defective monitor Replace monitor. (*)
Engine coolant temperature caution Lowered coolant level, leakage of Check, add coolant, repair by refer-
lamp lights up. coolant ring to CHECKS BEFORE START-
ING.
Dirt or scale accumulated in cooling Change coolant, flush inside of cool-
system ing system by referring to WHEN RE-
QUIRED.
Clogged radiator fins or damaged fin Clean or repair. See WHEN RE-
QUIRED.
Defective thermostat Replace thermostat. (*)
Loose radiator filler cap (in high alti- Tighten the cap or replace packing.
tude operation)
Defective monitor Replace monitor. (*)

3-266
Operation Troubles and Procedures

Problem Main causes Remedy

Starting motor operates but engine Lack of fuel Add oil to specified level. See
does not start. CHECKS BEFORE STARTING.
Air is mixed in fuel system. Repair the part where air is sucked in.
Defective fuel injection pump or de- Replace pump or nozzle. (*)
fective nozzle
Starting motor incapable of cranking See “Troubles and Procedures on
engine smoothly. Electrical System”.
Improper compression Adjust valve clearance. (*)
(Incorrect valve clearance)
Exhaust gas color is white or bluish. Excessive oil in oil pan Add oil to specified level. See
CHECKS BEFORE STARTING.
Improper fuel Replace with specified fuel.
Water entry in muffler Check and repair. (*)
Muffler breakage Replace muffler. (*)
Exhaust gas sometimes becomes Muffler breakage Replace muffler. (*)
black.
Combustion sound sometimes fluctu- Defective nozzle Replace nozzle.
ates
Unusual noise is generated. Low grade fuel being used Replace with specified fuel.
(Combustion or mechanical) Overheating Refer to “Engine coolant temperature
caution lamp lights up” shown above.
Damage inside muffler Replace muffler. (*)
Excessive valve clearance Adjust valve clearance. (*)
DEF level caution lamp is displayed
Lowering of DEF level Add DEF.
on monitor.
Action level or caution lamp is dis-
Contact your Komatsu distributor.
played on monitor.
Alarm buzzer sounds. Contact your Komatsu distributor.
Engine suddenly loses power.
Contact your Komatsu distributor.
(Entered derate mode.)

3-267
Troubles and Procedures Operation

If Machine Monitor Shows Warning Display

When the action level display (1) or caution lamp (2) is shown
on the display of the machine monitor, press switch F5 to dis-
play the “Current Abnormality” screen and check the details
and remedy.
Take the actions according to the message shown on the ma-
chine monitor, and check the failure code, and then ask your
Komatsu distributor for repair, as necessary.

The Contact Telephone Number If an Error Occurs

When an error screen is displayed on the monitor, press the
switch F5 to display the “Current Abnormality” screen and tele-
phone number (3) for the point of contact is displayed in the
message column at the bottom of the screen.
REMARK
If no point of contact telephone number is registered, no tele-
phone number is displayed.
Ask your Komatsu distributor for the telephone number regis-
tration if necessary.

3-268
 Maintenance

Please read and make sure that you understand the SAFETY section before
reading this section.

4-1
Precautions for Maintenance Maintenance

Precautions for Maintenance

Do not perform any inspection and maintenance operation that are not found in this manual.

Examine Service Meter Reading

Check the service meter reading every day to see if the maintenance time has come for any necessary mainte-
nance item to be performed.

Komatsu Genuine Replacement Parts

Komatsu recommends using Komatsu genuine parts specified in Parts Book as replacement parts.

Komatsu Genuine Lubricants

For lubrication of the machine, Komatsu recommends using Komatsu genuine lubricants. Moreover use oil of
the specified viscosity according to the ambient temperature.

Always Use Clean Washer Fluid

Use automobile window washer fluid, and be careful not to let any dirt get into it.

Clean Lubricants
Use clean oil and grease. Also, keep the containers of the oil and grease clean. Keep foreign materials away
from oil and grease.

Examine Drained Oil and Used Filter

At the replacement of the filters when oil is changed, check the old oil and filters for metal particles and foreign
materials. If large quantity of metal particles or foreign materials are found, always report to the person in
charge, and perform suitable action.

Precautions When You Refill Oil or Fuel

If your machine is equipped with a strainer, do not remove it while filling oil or fuel.

Precautions When You Add DEF

Do not remove the strainer while adding DEF.
It is recommended to use a nozzle having a diameter and a length specified by ISO 22241-4 and an auto stop
function to add DEF.

Precautions for Welding

• When performing welding, turn the starting switch to OFF position, check that the system operating lamp is
not lit. Turn the battery disconnect switch to OFF position, and remove the key.
• Do not apply a voltage higher than 200 V continuously.
• Connect grounding cable within 1 m {3 ft 3 in} of the area to be welded. If grounding cable is connected
near instruments, connectors, etc., the instruments may malfunction.
• Prevent seals, bearings or bushings from entering the space between the weld zone and grounding point.
Seals and the like can cause damage to the nearby parts by catching fire from sparks.
• Do not use the area around the work equipment pins or the hydraulic cylinders as the grounding point.
Sparks generated there can damage the plated portion.

Do Not Drop Things Inside Machine

• When opening the inspection windows or the oil filler port of the tank to perform inspection, be careful not to
drop nuts, bolts, or tools inside the machine.
If such things are dropped inside the machine, it may cause damage and/or malfunction of the machine,
and will lead to failure. If anything drops, be sure to take it out.

4-2
Maintenance Precautions for Maintenance

• Do not put unnecessary things in your pockets. Carry only things which are necessary for inspection.

Burn Prevention
Do not touch the hot parts, such as the engine, oil or coolant during inspection and maintenance.

4-3
Precautions for Maintenance Maintenance

Dusty Jobsites
When working at dusty jobsites, observe the following.
• Clean the radiator fins and other parts of the heat exchange equipment more frequently, and take care not
to let the fins become clogged.
• Replace the fuel filter more frequently.
• Clean electrical components, especially the starting motor and alternator, to avoid accumulation of dust.
• When checking and replacing the oil or filters, move the machine to a place where there is no dust and take
care to prevent dust from entering the system.

Avoid Mixing Oil

Never mix different brand or grade of oil. If a different brand or grade of oil has to be added, drain the old oil and
replace all the oil with the new brand or grade of oil.

Precautions for Opening and Closing Radiator Grille

• Stop the engine before opening or closing the radiator grille, and open or close it while the fan is stopped. If
you touch the fan when it is rotating, it will cause serious personal injury or death.
• Be careful not to get your fingers caught between the tank, etc. when opening or closing the radiator grille.
• Check that the lock is securely set when opening the radiator grille. Check that there is no abnormality in
the lock or link portion as well.
• When opening the radiator grille, be careful not to hit your head, etc. against it.
• Check the hoses and piping which move together with the radiator grille for cracks and damage.

Precautions When You Open Inspection Cover

Do not move the blade while the front cover and the engine side cover on the left side of the machine are open.
The blade and cover may contact with each other, and the cover may be damaged.

Lock Inspection Covers

Lock inspection cover securely into position with the lock bar, etc. If inspection or maintenance is performed with
inspection cover not locked in position, there is a danger that it may be suddenly shut by the wind and cause
personal injury.

Bleed Air from Hydraulic System

When hydraulic equipment is repaired or replaced, or the hydraulic piping is disconnected, the air must be bled
from the circuit.

Precautions When You Install Hydraulic Hoses

• When removing parts at locations where there are O-rings or gasket seals, clean the mounting surface, and
replace them with new parts.
When doing this, be careful not to forget to assemble O-rings and gaskets.
• When installing the hoses, do not twist them or bend them sharply.
If they are installed so, their service life will be extremely shortened and they may be damaged.

4-4
Maintenance Precautions for Maintenance

Checks After Inspection and Maintenance

If you forget to perform the inspection and maintenance, unexpected problems may occur, and this may lead to
personal injury. Always observe the following.
Checks After Operation (with Engine Stopped)
• Have any inspection and maintenance points been forgotten?
• Have all inspection and maintenance items been performed correctly?
• Have any tools or parts been dropped inside the machine? It is particularly dangerous if parts are dropped
inside the machine and get caught in the lever linkage mechanism.
• Are there any leakage of coolant or oil? Have all nuts and bolts been tightened?
Checks While the Engine Runs
To perform inspection while the engine is running, one worker must always sit on the operator's seat and be
ready to stop the engine at any time. All workers must maintain contact with the other workers.
• Increase the engine speed to check for the leakage of fuel or oil.
• Check if the inspected and serviced area is normally operated.

Select Fuel and Lubricants by Ambient Temperature

It is necessary to select fuel or lubricant according to the ambient temperature.

4-5
Outline of Maintenance Maintenance

Outline of Maintenance
• Komatsu recommends using Komatsu genuine parts for replacement parts, grease or oil.
• When changing the oil or adding oil, do not mix different types of oil. When changing the type of oil, drain all
the old oil and fill completely with the new oil. Always replace the filter at the same time. (There is no prob-
lem if the small amount of oil remaining in the piping mixes with the new oil.)
• Unless otherwise specified, when the machine is shipped from the plant, it is filled with the oil and coolant
listed in the table below.
Item Type
Engine oil pan Engine oil EO15W40-LA (Komatsu genuine)
Final drive case Power train oil TO30 (Komatsu genuine)
Hydraulic tank Engine oil EO10W30-DH (Komatsu genuine)
Non-Amine Engine Coolant (AF-NAC) (Komatsu genuine) (density: 30% or
Radiator
above)

Handle Oil, Fuel, Coolant, and Do Oil Clinic

Oil
• Oil is used in the engine and hydraulic equipment under extremely severe conditions (high temperature,
high pressure), and deteriorates with use.
Always use oil that matches the grade and maximum and minimum ambient temperatures recommended in
Operation and Maintenance Manual.
Even if the oil is not dirty, always change the oil at the specified interval.
• Oil corresponds to blood in the human body, always be careful when handling it to prevent any impurities
(water, metal particles, dirt, etc.) from getting in.
The majority of failures with the machine are caused by the entry of such impurities.
Take particular care not to let any impurities get in when storing or adding oil.
• Never mix oils of different grades or brands.
• Always add the specified amount of oil.
Having too much oil or too little oil are both causes of failures.
• If the oil in the work equipment is not clear, there is probably water or air getting into the circuit. In such
cases, consult your Komatsu distributor.
• When changing the oil, always replace the related filters at the same time.
• We recommend that you have an oil analysis periodically to check the condition of the machine. For those
who wish to use this service, consult your Komatsu distributor.
• When shipped from the plant, Engine oil EO10W30–DH is used.

4-6
Maintenance Outline of Maintenance

Fuel
• To prevent the moisture in the air from condensing and forming water inside the fuel tank, always fill the fuel
tank with fuel after completing the day's work.
• The fuel pump is a precision equipment, and if fuel containing water or dirt is used, it cannot work properly.
• Be extremely careful not to let impurities get in when storing or adding fuel.
• Always use the fuel specified for the temperature that is described in Operation and Maintenance Manual.
• If the fuel is used at the temperatures lower than the specified temperature (particularly at tempera-
tures below -15 °C {5 °F} ), the fuel will solidify.
• If the fuel is used at temperatures higher than the specified temperature, the viscosity will drop, and it
may result in troubles such as a drop of output.
• Before starting the engine, or after 10 minutes of adding fuel, drain the sediment and water from the fuel
tank.
• If the engine runs out of fuel, or if the filters are replaced, it is necessary to bleed the air from the circuit.
• If there is any foreign material in the fuel tank, wash the tank and fuel system.
NOTICE
Always use ultra-low-sulfur diesel fuel.
The ASTM diesel fuel recommended by Komatsu may contain 5 % or less of biofuel. The EN diesel fuel
may contain 7 % or less of it. Use the fuel which is filled into the storage tank or the fuel tank of the
machine as soon as possible.
When the diesel fuel is changed to the one mixed with the bio-fuel, replace the fuel prefilter cartridge
and the fuel main filter cartridge with new ones.

Coolant and Water for Dilution

• The coolant has the important function of preventing corrosion as well as preventing freezing.
Even in the areas where freezing is not an issue, the use of coolant is essential.
Komatsu machines are supplied with Non-Amine Engine Coolant (AF-NAC). Non-Amine Engine Coolant
(AF-NAC) has excellent anti-corrosion, antifreeze and cooling properties and can be used continuously for
2 years or 4000 hours.
Komatsu recommends the use of Non-Amine Engine Coolant (AF-NAC). If you use another coolant, it may
cause serious problems, such as corrosion of the engine and aluminum parts of the cooling system.
• When using antifreeze, always observe the precautions given in Operation and Maintenance Manual.
• Non-Amine Engine Coolant (AF-NAC) is already diluted with distilled water, so it is not flammable.
• The coolant density needs to be changed according to the ambient temperature.
Even in areas where it is not considered necessary to prevent freezing, always use Non-Amine Engine
Coolant (AF-NAC) with a density of over 30 % in order to prevent corrosion of the cooling system.
Non-Amine Engine Coolant (AF-NAC) is diluted with distilled water that does not contain any ions or water-
hardening substances. Never dilute with water.
• If the engine overheats, wait for the engine to cool before adding coolant.
• If the coolant level is low, it will cause overheating, and will also cause problems with corrosion due to air
entering the coolant.

4-7
Outline of Maintenance Maintenance

DEF
• If DEF gets on your skin, it may cause inflammation. Immediately take the contaminated clothes or shoes
off and wash it off with water. In addition, use a soap to wash it off thoroughly. If your skin becomes irritated
or begins to hurt, immediately consult a doctor for treatment.
• Do not induce vomiting if swallowed. If swallowed, thoroughly rinse mouth with water and consult a doctor
for treatment.
• Avoid contact with the eyes. If there is contact, flush with clean water for several minutes and consult a doc-
tor for treatment.
• Wear protective eyeglasses when exposed to DEF to protect from solution splashing in your eyes. Wear
rubber gloves when you perform work handling DEF to avoid skin contact.
• When opening the cap of DEF tank of the machine, the ammonia vapor may escape. Keep your face away
from the filler port.
• Do not put fluid other than DEF into DEF tank. If diesel fuel or gasoline is added into the tank, it can cause
a fire. Some fluids or agents added can create and emit a toxic gas.
• DEF is non-flammable; however, in the case of a fire it may generate an ammonia gas.
• If DEF is spilled, immediately wash and clean the area with water. If spilled DEF is left unattended and the
area is not washed and cleaned, it can cause corrosion to the contaminated area and emit toxic gas.
• When disposing of DEF, treat it as an industrial waste. The container for DEF is an industrial waste as well.
It should be treated in the same way.
• Never use an iron or aluminum container when disposing DEF, because toxic gas may develop and a
chemical reaction may corrode the container. Use a container made of resin (PP, PE) or stainless steel
when handling the fluid waste of DEF.
NOTICE
If you add any additional additive agents or water to DEF, the devices in the Urea SCR system may be
defective, and conformance to the exhaust gas regulations will be lost.

Grease
• Grease is used to prevent seizure and noises at the joints.
• This construction equipment is used under heavy-duty conditions. Komatsu recommends using the recom-
mended grease and follow the replacement intervals and recommended ambient temperatures given in this
Operation and Maintenance Manual.
• Grease fittings not included in the periodic maintenance section are the grease fittings for overhaul, so they
do not need grease.
If any part becomes stiff after being used for long time, add grease.
• Always wipe off all of the old grease that is pushed out when greasing.
Be particularly careful to wipe off the old grease in places where sand or dirt sticking in the grease would
cause wear of the rotating parts.

4-8
Maintenance Outline of Maintenance

Do KOWA (Komatsu Oil Wear Analysis)

KOWA is a maintenance service that makes it possible to prevent machine failures and downtime. With KOWA,
the oil is periodically sampled and analyzed. This enables early detection of wear of the machine drive parts and
other problems.
Thanks to long term experience and ample data accumulated, we can grasp condition of your machine accu-
rately and provide proper recommendation.
We strongly recommend you to use this service. The oil analysis is performed at actual cost, so the cost is low,
and results of the analysis and recommendations are reported promptly.
Analysis Items
Measurement of metallic powder concentration
An ICP (Inductively Coupled Plasma) analyzer is used for
measuring the concentration of iron, copper, and other metal
powder in the oil.

Measurement of quantity of iron particles

A PQI (Particle Quantifier Index) measuring instrument is used
for measuring the quantity of iron particles of 5 μm or more, en-
abling early detection of failures.

Others
Measurements are made of items such as the ratio of water, coolant, and fuel in the oil, and dynamic viscosity, if
necessary, to enable a highly precise diagnosis of the machine and the components' condition.
Oil Collection Interval
500 hours
Precautions When You Collect Oil
• Make sure that the oil is well mixed before sampling.
• Perform sampling at regular fixed intervals.
• Do not perform sampling on rainy or windy days when water or dust can get into the oil.
For further details of KOWA, contact your Komatsu distributor.

4-9
Outline of Maintenance Maintenance

Store Oil and Fuel

• Keep oil and fuel indoors to prevent any water, dirt, or other impurities from getting in.
• When keeping drum cans for a long period, lay the drums so that the filler ports of the drums are located in
the lower part of the side to prevent moisture from being sucked in. If drums have to be stored outside, cov-
er them with a waterproof sheet or take other measures to protect them.
• To prevent any change in quality during long-term storage, be sure to use in the order of first in - first out
(use the oldest oil or fuel first).

Store DEF
• Completely seal up its container for storage. Only open containers in a well-ventilated area.
• When storing DEF, avoid direct sunlight. Always use the original container. Make sure that transfer equip-
ment and tank must meet DEF compatible material specification. If DEF is stored in an iron or aluminum
container, toxic gas may develop and a chemical reaction may corrode the container.
• The relationship between the upper limit of storage temperature and the storage period of DEF is shown in
the table.
Temperature of storage area Storage period
Max.10 °C {50 °F} Up to 36 months
Max.25 °C {77 °F} Up to 18 months
Max.30 °C {86 °F} Up to 12 months
Max.35 °C {95 °F} Up to 6 months

*: Do not store DEF in the temperature of 35 °C {95 °F} or above.

Filter
• Filters are extremely important safety parts. They prevent impurities in the oil, fuel, and air circuits from en-
tering important equipment and causing problems. Replace all filters periodically. For details, see Operation
and Maintenance Manual.
However, when working in severe conditions, replace the filters at shorter intervals according to the oil and
fuel (sulfur content) being used.
• Never try to clean and use again the filters (cartridge type). Always replace them with new filters.
• When replacing oil filters, check if any metal particles are attached to the old filters.
If any metal particles are found, consult your Komatsu distributor.
• Do not open packages of spare filters until just before they are to be used.
• Komatsu recommends using Komatsu genuine filters.

4-10
Maintenance Outline of Maintenance

Handle Electrical Components

k WARNING
• When the battery disconnect switch key is turned to OFF position for the maintenance work, always
pull out the key and keep it with you. If the key is left in the switch, someone may turn ON the power
by mistake. It is dangerous that causes an electric shock.
• It is extremely dangerous if the electrical component becomes wet or the covering of the wiring is
damaged. This will cause an electrical leakage and may lead to malfunction of the machine. Do not
wash the inside of the operator's cab with water. When washing the machine, be careful not to let
water get into the electrical components.

• When removing the connectors of electrical components after washing the machine or in the rain, wipe off
the water drop stuck around connectors before removing the connectors and keep the water drop away
from inside of the connectors.
• Checking and maintenance items are checking fan belt tension, checking damage of the fan belt and
checking battery fluid level.
• Komatsu recommends installing electric components specified by Komatsu.
• External electro-magnetic interference may cause malfunction of the control system controller. Accordingly,
consult your Komatsu distributor before installing a radio receiver or other wireless equipment to the ma-
chine.
• When working at the seashore, keep the electrical component clean to prevent corrosion.
• When installing electrical component, connect it to the special power supply connector.
Do not connect the optional power supply to the fuse or starting switch or battery relay, etc.

Handle Hydraulic Components

• The hydraulic system is at high temperature during and just after operation. In addition, high pressure is
applied to the hydraulic system, thus pay attention to the following matters when performing inspection and
maintenance of it.
• Lower the work equipment to the ground on a level place, and work so that no pressure is applied to
the cylinder circuits.
• Be sure to stop the engine.
• Since the hydraulic oil and lubricating oil are at high temperature and high pressure just after operation,
wait until the oil temperature at each part decreases, and then start maintenance.
Internal pressure may be high even after the temperature decreases.
When loosening a plug, screw, or hose, avoid standing in front of them and loosen gradually and re-
lease the internal pressure, and then remove.
• When performing inspection and maintenance of the hydraulic circuit, be sure to release air from the
hydraulic tank to release the internal pressure.
• The inspection and maintenance include check of the hydraulic oil level, replacement of filters, replacement
of the hydraulic oil.
• When the high-pressure hoses, etc. are disconnected, check the O-rings for damage. If they are damaged,
replace them.
• When the hydraulic oil filter element or strainer is replaced or cleaned, or when a hydraulic component is
repaired, replaced, or its piping is removed, air in the circuit must be bled.
• The accumulator is charged with high-pressure nitrogen gas, and it is extremely dangerous if it is handled
incorrectly.

4-11
Standard Tightening Torque for Bolts and Nuts Maintenance

Standard Tightening Torque for Bolts and Nuts

Tightening Torque List
k CAUTION
If nuts, bolts, or other parts are not tightened to the specified torque, it will cause looseness or damage
to the tightened parts, and this will cause failure of the machine or problems with operation. Always be
careful when tightening parts.

Unless otherwise specified, tighten the metric nuts and bolts to

the torque shown in the table below.
If it is necessary to replace any nut or bolt, Komatsu recom-
mends using Komatsu genuine part of the same size as the
part that is removed.

Thread Tightening torque

Width
diame-
across Target value Allowable range
ter of
flats “b”
bolt “a”
(mm) Nm kgfm lbft Nm kgfm lbft
(mm)
6 10 13.3 1.35 9.8 11.8 to 14.7 1.2 to 1.5 8.7 to 10.8
8 13 31 3.2 22.8 27 to 34 2.8 to 3.5 20.3 to 25.3
10 17 67 6.8 48.8 59 to 74 6 to 7.5 43.4 to 54.2
12 19 111 11.3 81.4 98 to 123 10 to 12.5 72.3 to 90.4
14 22 172 17.5 127 153 to 190 15.5 to 19.5 112 to 141
16 24 260 26.5 192 235 to 285 23.5 to 29.5 170 to 213
18 27 360 37 268 320 to 400 33 to 41 239 to 297
20 30 510 52.3 378 455 to 565 46.5 to 58 336 to 420
22 32 688 70.3 508 610 to 765 62.5 to 78 452 to 564
24 36 883 90 651 785 to 980 80 to 100 579 to 753
27 41 1295 133 957 1150 to 1440 118 to 147 853 to 1060
30 46 1715 175 1265 1520 to 1910 155 to 195 1120 to 1410
33 50 2205 225 1630 1960 to 2450 200 to 250 1450 to 1810
36 55 2745 280 2025 2450 to 3040 250 to 310 1810 to 2240
39 60 3260 333 2405 2890 to 3630 295 to 370 2130 to 2680

Tighten the hoses to the torque shown in the table.

4-12
Maintenance Standard Tightening Torque for Bolts and Nuts

Width Tightening torque

across
Nominal - No. of Target value Allowable range
flats
threads “a”
“b”
Nm kgfm lbft Nm kgfm lbft
(mm)
9/16-18UNF 19 44 4.5 32.5 35 to 54 3.5 to 5.5 25.3 to 39.8
11/16-16UN 22 74 7.5 54.2 54 to 93 5.5 to 9.5 39.8 to 68.7
13/16-16UN 27 103 10.5 75.9 84 to 132 8.5 to 13.5 61.5 to 97.6
1-14UNS 32 157 16.0 115.7 128 to 186 13.0 to 19.0 94.0 to 137.4
1 3/16-12UN 36 216 22.0 159.1 177 to 245 18.0 to 25.0 130.2 to 180.8

4-13
Maintenance Schedule Maintenance

Maintenance Schedule
• When using the engine oil for cold district, the maintenance intervals of the engine oil and filter cartridge are
changed to for every 250 hours.
• If the currently used diesel fuel which does not include the bio-fuel is changed to the one mixed with the
bio-fuel, the replacement interval of the fuel filter is changed as well. See “MAINTENANCE INTERVAL
WHEN DIESEL FUEL MIXED WITH BIO-FUEL IS USED”.
• Ask your Komatsu distributor for changing the maintenance interval of the machine monitor.
Maintenance Schedule Table
When Required .............................................................................................................................................. 4-17
How to Examine, Clean and Replace Air Cleaner ................................................................................... 4-17
How to Clean Inside of Cooling System .................................................................................................. 4-23
How to Clean Inside Machine.................................................................................................................. 4-27
How to Examine and Clean Front Surface of Radiator ............................................................................ 4-28
How to Examine and Adjust Track Tension ............................................................................................. 4-29
How to Examine Looseness and Tighten Track Shoes Bolts................................................................... 4-32
Examine Oil Level in Idler........................................................................................................................ 4-33
How to Adjust Idler Clearance................................................................................................................. 4-34
Invert and Replace Cutting Edge and End Bit ......................................................................................... 4-36
Clean and Examine Radiator Fins and Oil Cooler Fins............................................................................ 4-37
Clean Hydraulic Tank Breather................................................................................................................ 4-41
Clean Fuel Tank Breather ....................................................................................................................... 4-41
Replace Door Damper ............................................................................................................................ 4-42
Lubricate Door Hinge .............................................................................................................................. 4-42
How to Examine Door Latch.................................................................................................................... 4-42
Examine Door Lock Striker...................................................................................................................... 4-42
How to Examine Window Washer Fluid Level, Add Fluid ........................................................................ 4-43
How to Examine Wiper Blade.................................................................................................................. 4-44
Replace Wiper Blade .............................................................................................................................. 4-44
How to Examine and Do Maintenance Air Conditioner ............................................................................ 4-46
How to Bleed Air from Hydraulic Circuit................................................................................................... 4-50
Procedure to Release Internal Pressure in Hydraulic Circuit ................................................................... 4-51
How to Examine Electrical Intake Air Heater ........................................................................................... 4-51
Adjust Shim of Center Ball ...................................................................................................................... 4-52
How to Adjust Shims at Pitch Ball ........................................................................................................... 4-53
Examine Before You Start Operation.............................................................................................................. 4-54
Every 50 Hours Maintenance ......................................................................................................................... 4-55
Lubrication .............................................................................................................................................. 4-55
How to Lubricate Equalizer Bar Center Pin ............................................................................................. 4-55
Every 250 Hours Maintenance ....................................................................................................................... 4-56
Lubrication .............................................................................................................................................. 4-56
How to Lubricate Equalizer Bar Side Pin................................................................................................. 4-56
How to Examine Oil Level in Final Drive Case, Add Oil........................................................................... 4-57
How to Examine Battery Electrolyte Level............................................................................................... 4-58
How to Examine Brake Performance Curve ............................................................................................ 4-61
Every 500 Hours Maintenance ....................................................................................................................... 4-62
Change Oil in Final Drive Case ............................................................................................................... 4-62
How to Change Oil in Engine Oil Pan and Replace Engine Oil Filter Cartridge ....................................... 4-62
How to Replace Fuel Prefilter Cartridge .................................................................................................. 4-65
Replace Air Conditioner Fresh/Recirc Air Filters ..................................................................................... 4-68
How to Examine Electric Wiring Around Starting Motor and Alternator.................................................... 4-69
Every 1000 Hours Maintenance ..................................................................................................................... 4-70
How to Replace Fuel Main Filter Cartridge.............................................................................................. 4-71
Replace Fuel Tank Breather Element ...................................................................................................... 4-74
How to Examine All Tightening Points of Engine Intake Pipe Clamps ..................................................... 4-74
Replace Hydraulic Tank Breather Element .............................................................................................. 4-74
Replace DEF Tank Breather Element...................................................................................................... 4-75

4-14
Maintenance Maintenance Schedule

Examine and Replace Alternator Drive Belt Tension and Replacing Alternator Belt ................................ 4-76
Examine for Looseness of ROPS Mount Bolt .......................................................................................... 4-76
How to Examine and Clean Fan.............................................................................................................. 4-77
Every 2000 Hours Maintenance ..................................................................................................................... 4-79
Change Oil in Hydraulic Tank, Replace Hydraulic Oil Filter Cartridge, Replace HST Oil Filter Cartridge, and
Clean Hydraulic Tank Strainer ............................................................................................................. 4-79
How to Examine Function of Accumulator for Control Circuit and Release Internal Pressure in Hydraulic Cir-
cuit ...................................................................................................................................................... 4-83
How to Examine Alternator...................................................................................................................... 4-85
How to Examine and Adjust Engine Valve Clearance.............................................................................. 4-85
How to Examine Vibration Damper ......................................................................................................... 4-86
Replace KCCV Filter Element ................................................................................................................. 4-86
Replace DEF Filter.................................................................................................................................. 4-90
Every 4000 Hours Maintenance ..................................................................................................................... 4-93
Replace Defined Life Parts...................................................................................................................... 4-93
Examine Water Pump ............................................................................................................................. 4-93
How to Examine Starting Motor............................................................................................................... 4-93
How to Replace Accumulator (For Control Circuit) .................................................................................. 4-94
How to Examine for Looseness of Engine High-Pressure Piping Clamp, Hardening of Rubber............... 4-95
How to Examine for Missing Fuel Spray Prevention Cap, Hardening of Rubber...................................... 4-96
Every 4500 Hours Maintenance ..................................................................................................................... 4-97
How to Clean DEF Tank .......................................................................................................................... 4-97
How to Clean DEF Tank Mounting Part ................................................................................................... 4-97
How to Replace DEF Tank Filler Port Filter ............................................................................................. 4-97
Every 8000 Hours Maintenance ..................................................................................................................... 4-98
How to Replace Fuel Spray Prevention Cap ........................................................................................... 4-98
Every 9000 Hours Maintenance ..................................................................................................................... 4-99
How to Replace DEF Hose ..................................................................................................................... 4-99

4-15
Maintenance Schedule Maintenance

Maintenance Interval When Diesel Fuel Mixed with Bio-Fuel is Used

If the diesel fuel which does not include the bio-fuel is changed to the diesel fuel mixed with bio-fuel, set the
maintenance interval as follows.
Replace the fuel prefilter cartridge
When the machine is operated first 250 hours after the diesel fuel has been changed to the diesel fuel mixed
with bio-fuel, and when the machine is operated further 250 hours.
After that, replace it within 500 hours as a periodic replacement by the service meter reading.
Replace the fuel main filter cartridge
When the machine is operated first 250 hours after the diesel fuel has been changed to the diesel fuel mixed
with bio-fuel, and when the machine is operated further 250 hours.
After that, replace it within 1000 hours as a periodic replacement by the service meter reading.

Maintenance Interval After the Diesel Fuel is Changed to the Diesel Fuel Mixed with Bio-Fuel
Operating hours of the machine Service meter
Every 500 hours Every 1000 hours
250 hours 500 hours Within 500 After 500 op- Within 500 After 500 op-
When
after chang- after chang- operating erating hours operating erating hours
changed
ing ing hours after after chang- hours after after chang-
changing ing changing ing
Fuel prefilter
Replace. Replace. Replace. - Replace. - Replace.
cartridge
Fuel main fil-
Replace. Replace. Replace. - - - Replace.
ter cartridge

4-16
Maintenance Maintenance Procedure

Maintenance Procedure
When Required
How to Examine, Clean and Replace Air Cleaner
k WARNING
• If inspection, cleaning, or maintenance is performed while the engine is running, dust enters into
the engine and damages it. Be sure to stop the engine before performing these works.
• When using compressed air, there is a danger that dirt may scatter and cause personal injury. Al-
ways wear protective equipment such as protective eyeglasses and dust mask.
• When working in high places or where the foothold is poor, be careful not to fall because of the re-
action when pulling out the element.

Check
NOTICE
Do not clean the element before the air cleaner clogging caution lamp lights up or the yellow piston of
the dust indicator laps over the peripheral red zone.
If the element is cleaned before the above, the air cleaner cannot display its normal performance and
the cleaning effect decreases.
In addition, during the cleaning operation, more dirt stuck to the element will fall inside the inner ele-
ment.
In the following cases, clean or replace the air cleaner element.
• When the air cleaner clogging caution lamp lights up

4-17
Maintenance Procedure Maintenance

• When the inside yellow piston of dust indicator (1) laps

over the peripheral red zone (A)

4-18
Maintenance Maintenance Procedure

How to Clean and Replace Outer Element

1. Open the engine side cover on the left side of the machine.
2. Remove the clips (2) (3 places) and remove the cover (3).

NOTICE
• After the outer element has been cleaned 6 times, or if
the air cleaner element has been used for 1 year, re-
place the outer element, inner element, and O-ring.
• When cleaning the cover, do not remove the vacuator
valve (6).
• Before and after cleaning the element, do not leave or
keep it under direct sunlight.
• Never remove the inner element (5). If it is removed,
dirt will enter and can cause an engine trouble.
• Do not use a screwdriver or other tool.
3. Hold the outer element (4), rock it lightly up and down and to the right and left, and pull it out while turning it
to the right or left.
4. Cover the air connector at the bottom of the air cleaner body with a clean cloth or tapes to prevent entry of
dirt.
5. Clean the interior of the air cleaner body, cover (3) and vacuator valve (6) with a clean cloth, a whisk or
others.
6. Blow dry compressed air (0.2 MPa {2.1 kgf/cm2} or less)
from the inside of the outer element along the pleats.
7. Blow dry compressed air from the outside of the outer ele-
ment along the pleats.
8. Blow dry compressed air again from the inside of the outer
element.

NOTICE
If small holes or thinner parts are found on the element
when it is checked with an electric bulb after cleaning and
drying, replace the element.
When cleaning the element, do not hit it or beat it against
something.
Do not use the element with damaged pleats or a damaged
gasket or seal.
9. Remove the cloth or tapes attached in the step 4.
10. Check the seal of the cleaned or new element for adhesion
of dusts and oil.

4-19
Maintenance Procedure Maintenance

Wipe off all of sticking oil, etc., if any.

NOTICE
• Do not clean and reuse the inner element. When replacing the outer element, replace the inner
element with new one at the same time.
• If the outer element and cover are installed while the inner element is not installed properly, the
outer element may be damaged.
• The sealing portion of the improper part lacks precision, and allows the entry of dust, which
leads to damage of the engine. Do not use such improper part.
11. Check that the inner element is fitted securely.
If the inner element is not fitted securely, push it in properly.
12. Install the cleaned outer element.
NOTICE
• When installing the cover (3), check the O-ring (7)
for a scratch, etc. If it has any scratch, etc., re-
place it.
• When installing the cover (3), press it to the case
securely, and check that clips (2) are secured cor-
rectly at 3 places.
13. Set the arrow mark on cover (3) toward the top, install it to
the air cleaner body, then secure it with clips (2).
14. Push the button of dust indicator (1).
The yellow piston returns.
REMARK
• Immediately after a new element has been installed,
the yellow piston of the dust indicator may go to the
position in the range of 3.7 to 5.0 kPa {0.04 to
0.05 kgf/cm2, 0.57 to 0.71 PSI}, but this does not indi-
cate any abnormality.
• For the machines installed with a pre-cleaner of large
intake resistance or a rain cap, immediately after a
new element has been installed, the yellow piston of
the dust indicator may go to the position in the range
of 5.0 to 6.2 kPa {0.05 to 0.06 kgf/cm2, 0.71 to
0.85 PSI}, but this does not indicate any abnormality.
15. Peel off one seal from the recording sheet on the cover (3).
16. Close the engine side cover on the left side of the ma-
chine.

4-20
Maintenance Maintenance Procedure

How to Replace Element

1. Open the engine side cover on the left side of the machine.
2. Remove the clips (2) (3 places) and remove the cover (3).

NOTICE
• When cleaning the cover, do not remove the vacuator
valve (6).
• Before and after cleaning the element, do not leave or
keep it under direct sunlight.
• Never remove the inner element (5). If it is removed,
dirt will enter and can cause an engine trouble.
• Do not use a screwdriver or other tool.
3. Hold the outer element (4), rock it lightly up and down and
to the right and left, and pull it out while turning it to the
right or left.
4. Clean the interior of the air cleaner body, cover (3) and vacuator valve (6) with a clean cloth, a whisk or
others.
NOTICE
• If the outer element and cover are installed while the inner element is not installed properly, the
outer element may be damaged.
• Do not clean and reuse the inner element. When replacing the outer element, replace the inner
element with new one at the same time.
• The sealing portion of the improper part lacks precision, and allows the entry of dust, which
leads to damage of the engine. Do not use such improper part.
5. Remove the inner element (5), then install the new inner element immediately.
Install the inner element securely so that it does not move.
6. Install the new outer element (4).
NOTICE
• When installing the cover (3), check the O-ring (7)
for a scratch, etc. If it has any scratch, etc., re-
place it.
• When installing the cover (3), press it to the case
securely, and check that clips (2) are secured cor-
rectly at 3 places.
7. Replace the O-ring (7) of cover (3) with a new one.
8. Set the arrow mark on cover (3) at the top, install it to the
air cleaner body, then secure it with clip (2).

4-21
Maintenance Procedure Maintenance

9. Push the button of dust indicator (1).

The yellow piston returns.
REMARK
• Immediately after a new element has been installed,
the yellow piston of the dust indicator may go to the
position in the range of 3.7 to 5.0 kPa {0.04 to
0.05 kgf/cm2, 0.57 to 0.71 PSI}, but this does not indi-
cate any abnormality.
• For the machines installed with a pre-cleaner of large
intake resistance or a rain cap, immediately after a
new element has been installed, the yellow piston of
the dust indicator may go to the position in the range
of 5.0 to 6.2 kPa {0.05 to 0.06 kgf/cm2, 0.71 to
0.85 PSI}, but this does not indicate any abnormality.
10. Replace the seal stuck to cover (3) with a new one.
11. Close the engine side cover on the left side of the ma-
chine.

4-22
Maintenance Maintenance Procedure

How to Clean Inside of Cooling System

k WARNING
• Immediately after the engine is stopped, the coolant is still hot and the pressure is accumulated in
the radiator. If the cap is removed under this condition and the coolant is drained, it may cause a
burn. Wait for the temperature to go down, and then turn the cap slowly to release the pressure.
• Start the engine and clean it. When standing up or leaving the operator's seat, lock the parking
brake lever and work equipment lock lever.
• It is very dangerous to go under the machine for cleaning while the engine is running, since the ma-
chine may move unexpectedly. While the engine is running, never go under the machine.

Place the machine on a level ground when cleaning or changing the coolant.
For cleaning the inside of the cooling system and changing the coolant, see the following table.
Coolant Cleaning of inside of cooling system and replacement of coolant
Non-Amine Engine Coolant (AF-NAC) Every 2 years or 4000 hours, whichever comes sooner

The coolant has the important function of preventing corrosion as well as preventing freezing.
Even in the areas where freezing is not an issue, the use of coolant is essential.
Komatsu machines are supplied with Non-Amine Engine Coolant (AF-NAC). Non-Amine Engine Coolant (AF-
NAC) has excellent anti-corrosion, antifreeze and cooling properties and can be used continuously for 2 years
or 4000 hours.
Komatsu recommends the use of Non-Amine Engine Coolant (AF-NAC). If you use another coolant, it may
cause serious problems, such as corrosion of the engine and aluminum parts of the cooling system.
To maintain the anti-corrosion properties of Non-Amine Engine Coolant (AF-NAC), always keep the density of
Non-Amine Engine Coolant between 30 % and 64 %.
Non-Amine Engine Coolant (AF-NAC) is already diluted with distilled water. When using the coolant, investigate
the lowest temperature in the past and decide the density for the coolant from the following coolant density ta-
ble.
When deciding the density for the coolant, set it for a temperature 10 °C below the actual lowest temperature in
the working area.
The coolant density varies according to the ambient temperature, but it must be 30 % or more.

Coolant Density Table

-10 or
°C -15 -20 -25 -30 -35 -40 -45 -50
Min. atmospheric tem- more
perature 14 or
°F 5 -4 -13 -22 -31 -40 -49 -58
more
Density (%) 30 36 41 46 50 54 58 61 64

k WARNING
• Coolant is toxic. When opening the drain valve, be careful not to get coolant on you. If it gets in
your eyes, flush your eyes with large amount of fresh water and see a doctor immediately.
• When handling the cooling water containing coolant that has been drained during changing the
coolant or repairing the radiator, contact your Komatsu distributor or request a qualified company
to perform the operation. Coolant is toxic, so never pour it into drainage ditches or drain it onto the
ground surface.

Non-Amine Engine Coolant (AF-NAC) is already diluted with distilled water, so it is not flammable.
Check the density with a coolant tester.

4-23
Maintenance Procedure Maintenance

Prepare a hose to fill with coolant and water.

Prepare a container whose capacity is larger than the specified coolant volume to catch the drained coolant.
To close the heater valve, set the temperature setting of the air conditioner to the maximum cooling.
1. Place the machine on a level place.
2. Stop the engine.
3. Turn the radiator cap (1) slowly until it hits the stopper and
release the pressure.
4. While pushing the radiator cap (1), turn it until it hits the
stopper, then remove it.

5. Remove the engine side cover (2) on the right side of the
machine.

6. Remove the cover (3).

4-24
Maintenance Maintenance Procedure

7. Pull out the drain hose (4).

8. Remove the cover (5) under the front cover.

9. Place a container to catch the coolant under the drain
hose (4).
10. Open the drain valve (P) to drain the coolant.

REMARK
Keep air bleeding valve (6) open while adding the coolant
or water to the cooling system. The air which is collected
during adding of the coolant or water will be bled. After
adding the coolant or water, close the air bleeding valve
(6).
11. After draining the coolant, close the drain valve (P) and
add city water.
12. After the radiator is filled with water, start the engine.
13. Run the engine at low idle for approximately 10 minutes.
14. Stop the engine.
15. Open the drain valve (P) to drain the coolant.
16. Close the drain valve (P).
17. Add the Non-Amine Engine Coolant (AF-NAC) through the coolant filler port up to the mouth of the port.
For the concentration of Non-Amine Engine Coolant (AF-NAC), see “Coolant density table”.
18. Start the engine.
19. Run the engine at low idle for 5 minutes, and then run at full speed for further 5 minutes. (At this time, keep
the radiator cap removed.)
The air is bled from the coolant.
20. Open the hydraulic tank inspection cover on the left side of
the machine, and drain the coolant from the reservoir tank
(7).
21. Clean the inside of reservoir tank (7).

4-25
Maintenance Procedure Maintenance

22. Add Non-Amine Engine Coolant (AF-NAC) to the middle

between FULL and LOW.
23. Stop the engine.
24. Tighten the radiator cap (1).
25. Check the coolant level in reservoir tank (7).
If necessary, add Non-Amine Engine Coolant (AF-NAC).
26. After cleaning is finished, install all the removed covers
and close all the opened covers.

4-26
Maintenance Maintenance Procedure

How to Clean Inside Machine

k WARNING
If the compressed air, high-pressure water, or steam hits your body directly or dirt is scattered by use of
it, there is a danger of personal injury. Wear the protective equipment such as the protective eyeglasses
and dust mask.

Clean the inside of the machine when any sand, and dust is accumulated.
1. Remove the mounting bolts (1) (12 pieces) on the bottom
of the machine, and remove the covers (2), (3), and (4).
2. Remove the sands and dusts from inside of the machine.
3. After cleaning, install the covers (2), (3) and (4) on the bot-
tom of the machine with the mounting bolts (1) (12 pieces).

4-27
Maintenance Procedure Maintenance

How to Examine and Clean Front Surface of Radiator

k WARNING
If compressed air, high-pressure water, or steam hits your body directly or dirt is scattered by the com-
pressed air, high-pressure water, or steam, there is a danger of personal injury. Always wear protective
equipment such as protective eyeglasses and dust mask.

1. Open hydraulic tank inspection cover (1).

2. Check the front face of radiator for clogging.

If it is heavily clogged, remove cover (2) from the back of
the operator's seat, and clean it with compressed air, etc.

4-28
Maintenance Maintenance Procedure

How to Examine and Adjust Track Tension

The wear of the pins and bushings of the undercarriage depends on the working condition and soil conditions.
Check the track tension occasionally and keep it at the standard level.
Perform check and adjustment on a level and firm ground.

Check
1. Drive the machine forward on a flat place, and stop without
applying the brake.
2. Place a straight bar between the carrier roller and idler as
shown in the figure.
When clearance (a) between the bar and grouser is 20 to
30 mm {0.8 to 1.2 in} at the center, the tension is in the
standard range.
If the track tension is not in the standard range, adjust it.

Adjustment
k WARNING
Never loosen plug (1) more than 1 turn.
If plug (1) is loosened more than 1 turn, there is a danger
of plug (1) flying out under the high internal pressure of
the grease.
Never loosen any part other than plug (1). Never put your
face in the mounting direction of plug (1).
If the track tension cannot be loosened by the above pro-
cedure, ask your Komatsu distributor for repair.

Increase Track Tension

NOTICE
• The safety indicator is stuck to the back of cover (3). Take care not to damage the safety indicator.
• When removing cover (3), be careful not to let any dirt or soil get in.
Prepare a grease pump.
1. Remove cover (3).
2. Pump in grease through grease fitting (2) by using a
grease pump.

4-29
Maintenance Procedure Maintenance

Grease can be pumped in until dimension (S) becomes

zero (0). If the track tension is still loose, the pins and
bushings are excessively worn. The pins and bushings
need to be turned 180 deg. or replaced. Ask your Komatsu
distributor for repair.
3. Move the machine backward and forward.
4. Check the belt tension again.
Check that the track tension is proper.
If the track tension is not proper, adjust it again.

4-30
Maintenance Maintenance Procedure

How to Decrease Track Tension

k WARNING
It is extremely dangerous to release the grease by any method other than the following procedure.
If track tension is not relieved by this procedure, contact your Komatsu distributor for repairs.

NOTICE
• The safety indicator is stuck to the back of cover (3). Take care not to damage the safety indicator.
• When removing cover (3), be careful not to let any dirt or soil get in.
1. Remove cover (3).
2. Loosen plug (1) gradually to release the grease.
When loosening plug (1), turn it a maximum of 1 turn.
If the grease does not come out smoothly, move the ma-
chine forward and backward a short distance.
3. Tighten plug (1).
4. Move the machine backward and forward.
5. Check the belt tension again.
Check that the track tension is proper.
If the track tension is not proper, adjust it again.

4-31
Maintenance Procedure Maintenance

How to Examine Looseness and Tighten Track Shoes Bolts

NOTICE
If the machine is used with track shoe bolts loose, they will break. Tighten any loose bolt immediately.
1. Check for looseness of track shoe bolt (1).
2. If any bolt is loose, retighten it.

How to Retighten Track Shoe Bolt

1. Tighten the track shoe bolts in the order shown in the fig-
ure.
Tightening torque of shoe bolt: 196 ± 20 Nm {20 ± 2 kgfm,
145 ± 14.5 lbft}
2. Check that the nut and track shoe are in close contact with
the link contact surface.
3. After checking, retighten by 120 ± 10 °.

Retighten Master Link Connection Bolt

1. Tighten the master link connecting bolts in the order shown
in the figure.
Tightening torque for master link connecting bolt: 196
± 20 Nm {20 ± 2 kgfm, 145 ± 14.5 lbft}
2. Check that the link contact surfaces are fitted.
3. After checking, tighten by 180±10 °.

4-32
Maintenance Maintenance Procedure

Examine Oil Level in Idler

k WARNING
When the oil level is low and new oil must be added, the machine body needs to be inclined, and that is
dangerous.
Ask your Komatsu distributor for adding.

Low oil level in the idler can cause noise and seizure. Stop the machine on a flat place and check for the oil
level according to the following procedure.
1. Loosen plug (1) gradually and check that oil oozes out
through the thread portion.
• When oil oozes out through thread portion
You do not need to add oil.
• When no oil oozes out through thread portion
The oil is insufficient. Ask your Komatsu distributor for
adding.
2. After checking, tighten plug (1).

4-33
Maintenance Procedure Maintenance

How to Adjust Idler Clearance

Since the idlers are forced to move forward and backward by an external force, guide plates will be worn out.
Wear of guide plates will cause the vibration of idlers from side to side or inclination of the idlers, and running off
of track links from the idlers or unevenly worn idler and links may result.
Adjust as follows.

How to Adjust Idler Clearance Horizontally

1. Drive the machine by 1 to 2 m {3 ft 3 in to 6 ft 7in} on a flat place.
2. Measure the clearance (A) between track frame (1) and
guide plate (2) (4 places on the right and left, and inside
and outside).
• When clearance (A) is less than 4 mm {0.157 in} .
The clearance of the idler does not need to be adjus-
ted.
• When clearance (A) is 4 mm {0.157 in} or more
Adjust the clearance of the idler.

1) Loosen the bolts (3) (4 pieces).

Tightening torque: 245 to 309 Nm {25 to 31.5 kgfm,
181 to 228 lbft}
2) Remove some shims and adjust the clearance on
each side to 0.5 mm to 1 mm {0.02 in to 0.039 in}.
Thickness of 1 shim is 1 mm {0.039 in} .

4-34
Maintenance Maintenance Procedure

How to Adjust Idler Clearance Vertically

1. Measure the clearance (B) to know the adjustment amount, subtract 2 mm {0.08 in} from the value, and re-
cord it.
(Example) When clearance (B) is 5 mm {0.2 in} , the adjustment amount becomes (5 - 2 =) 3 mm {0.12 in} .
2. Loosen the bolts (1) (4 pieces) 3 turns each.
Do not turn the bolt more than 3 turns.
REMARK
Use the bolt with specified length. Do not change the
length.
3. Remove the bolts (2) (2 pieces) and remove the cover (3).
4. Pull out the shims so that the adjustment amount specified
at step 1. is achieved.
5. Put the removed shims (4) onto shim (5).
At this time, check that the total pieces of shim (4) and
shim (5) are the same as those before adjustment.
Thickness of 1 shim is 1 mm {0.04 in} type only.
6. Restore the cover (3) to the original position, and tighten
the bolts (2) (2 pieces).
7. Tighten the bolts (1) (4 pieces).
Tightening torque: 245 to 309 Nm {25 to 31.5 kgfm, 181 to
228 lbft}
8. Check the clearance (B).
When the clearance (B) is 2 mm {0.08 in} , adjustment is completed.

4-35
Maintenance Procedure Maintenance

Invert and Replace Cutting Edge and End Bit

k WARNING
It is dangerous if the work equipment moves by mistake when the cutting edge and end bit are turned
180 deg. or replaced.
Set the work equipment in a stable condition, place the work equipment lock lever to LOCK position,
then stop the engine.

Turn the cutting edges and end bits 180 degrees or replace them before they are worn out to the blade end.
1. Raise the blade to proper height, and place blocks under it to prevent it from lowering.
2. Set the work equipment lock lever to LOCK position.
3. Stop the engine.
4. Judge the wear of the end bit and cutting edge by the following wear standards.
Wear standards
Item Criteria (mm {in} )
Standard
No. Measuring point Repair limit
dimension
1 Height of end bit 102 {4.0} 85 {3.3}
2 Height of cutting edge 102 {4.0} 85 {3.3}

REMARK
• If both sides of the cutting edge are worn out, replace
with new ones.
• If the wear extends to the mounting surface, repair the
mounting surface before installing.
5. Loosen the nut (3) and remove the bolt (4).
6. Remove the cutting edge and end bit.
7. Clean the mounting face.
8. Turn the cutting edge and end bit 180 deg. or replace them
with new ones.
9. Install the cutting edge and end bit, and tighten them light-
ly.
If nut (3) and bolt (4) are damaged, replace them as well.
10. Press the blade against the ground to eliminate of the play
of bolt (4).
11. Tighten the bolt to the specified torque.
Tightening torque: 255±34 Nm {26±3.5 kgfm, 188 ± 25.3 lbft}
12. After operating the machine for several hours, retighten the mounting nuts.

4-36
Maintenance Maintenance Procedure

Clean and Examine Radiator Fins and Oil Cooler Fins

If there is any mud or dirt stuck to the radiator or oil cooler, clean them.
Check the rubber hoses. If they are cracked or fragile, replace them. Also, check the hose clamp for looseness.

Clean Fin by Reverse Rotation of Hydraulic Drive Fan

NOTICE
When the hydraulic drive fan rotates in reverse, take extreme care of scattering of dust.
When stopping the engine during the Fan Reverse Mode, first run the engine at low idle, then stop it.
The dust and dirt stuck to the radiator and cooler can be blown out by rotating the hydraulic drive fan in the
reverse direction.
1. Turn the starting switch (1) to OFF position and stop the
engine.

2. Operate the parking brake lever (2) and work equipment

lock lever (3) by holding the operating portion on the top,
and place the levers in LOCK position (L).

3. Remove the mounting bolts (8 pieces), and remove the

covers (4) and (5).

4-37
Maintenance Procedure Maintenance

4. Open the engine side cover (6).

5. Remove the front cover (7) and engine side covers (8) and
(9).
6. Open the hydraulic tank inspection cover (10).
7. Open the fuel tank inspection cover (11).
8. Turn the starting switch (1) to ON position.

9. With the user menu on the machine monitor, set “Machine

Setting” to the Fan Reverse Mode.
For setting of the Fan Reverse Mode, see “REVERSE HY-
DRAULIC FAN”.

REMARK
Even if Fan Reverse Mode is set while the engine is run-
ning, the fan rotation direction is not reversed.
The screen in the figure is displayed to inform the operator
that the direction of rotation of the fan has not been
changed.
Stop the engine once and perform the steps 3 to 8.
10. Turn the starting switch (1) to START position and start the
engine.
The hydraulic fan rotates in reverse.
11. Turn the fuel control dial at High idle (MAX) position, and run the engine at high idle.
Change the time for running the engine at high idle corresponding to the seriousness of clogging.
Normal clogging: 1 to 2 minutes
Excessive clogging: 2 to 3 minutes
12. After cleaning, turn the fuel control dial to Low idle (MIN) position.
Run the engine at low idle for approximately 10 seconds.
13. Turn the starting switch (1) to OFF position and stop the engine.

4-38
Maintenance Maintenance Procedure

REMARK
• If dirt is caught in the radiator fins, blow with compressed air to clean.
• Check that there is no dirt sticking to the aftertreatment devices, and area around the turbocharger.
• In a cold circumstance, perform the cleaning by the hydraulic fan reverse mode within less than 5 mi-
nutes.
If the fan reverse rotation is performed for a long time, the DEF hose may freeze.
14. Close the engine side cover (6), hydraulic tank inspection cover (10), and fuel tank inspection cover (11).
15. Install the front cover (7) and engine side covers (8) and (9) with mounting bolts.
16. Install the covers (4) and (5) with mounting bolts.

4-39
Maintenance Procedure Maintenance

Clean Radiator Fin

k WARNING
• If compressed air, high-pressure water, or steam hits your body directly or dirt is scattered by use
of them, there is a danger of personal injury. Wear the protective equipment such as the protective
eyeglasses and dust mask.
• When performing cleaning, always stop the engine and check that the fan is not rotating. If you
touch the fan when it is rotating, it will cause serious personal injury or death.

1. Remove the bolts (1) (2 pieces) on the lower part of the ra-
diator grille.

2. Pull the radiator grille backward and raise it upward.

Open the radiator grille to the fully opened position, check
that it is locked, and then release your hand.
3. Remove mud, dirt, leaves, etc. in the radiator fins.
Blow off the heavy clogging with the compressed air.
Steam or water may be used instead of compressed air.
4. Check the rubber hoses. If any hose is cracked or be-
comes brittle, replace it with a new one. Also check all the
hose clamps for looseness.
5. Close the radiator grille according to the following proce-
dure.
1) Lift up the radiator grille, and push lock releasing bar
(2) to the direction of arrow.
The lock is released.
2) Close the radiator grille.
6. Tighten the bolts (1) (2 pieces) on the lower part of the ra-
diator grille.

REMARK
• For opening and closing the radiator grille, see “METHOD FOR OPENING AND CLOSING RADIATOR
GRILLE”.
• For opening and closing the radiator grille of the machine equipped with ripper, see ATTACHMENTS AND
OPTIONS, “METHOD FOR OPENING AND CLOSING RADIATOR GRILLE”.

4-40
Maintenance Maintenance Procedure

Clean Hydraulic Tank Breather

At the check and maintenance, if the breather is dirty, clean it.
1. Remove nut (2) of breather assembly (1) on the top of the
hydraulic tank.
Use a tool when the nuts are so tight to remove.
2. Remove cover (3).
3. Remove dirt sticking to breather element (4).
4. Clean in clean diesel fuel or flushing oil.
5. Install cover (3) and nut (2).
Tightening torque: 10 to 14 Nm {1.0 to 1.4 kgfm, 7.23 to
13.7 lbft}

Clean Fuel Tank Breather

At the check and maintenance, if the breather is dirty, clean it.
1. Remove nut (2) of breather assembly (1) on the top of the
fuel tank.
Use a tool when the nuts are so tight to remove.
2. Remove cover (3).
3. Remove dirt sticking to breather element (4).
4. Clean in clean diesel fuel or flushing oil.
5. Install cover (3) and nut (2).
Tightening torque: 10 to 14 Nm {1.0 to 1.4 kgfm, 7.23 to
13.7 lbft}

4-41
Maintenance Procedure Maintenance

Replace Door Damper

Measure groove depth (A) of door damper rubber (1).
When groove depth (A) decreases to 2 mm {0.079 in} or less,
replace the damper.
The damper is installed at top and bottom, 2 pieces each on
the R.H. and L.H. doors.

Lubricate Door Hinge

Perform this when the door creaks when it opens or closes.
1. Supply spray lubricant through the bushing slit of the
hinge.
2. If the bushing is worn, replace the hinge.

How to Examine Door Latch

1. Keep the door open.
2. Check if the grease in the latch dried out.
If the amount of grease is low or there is no more grease,
coat the inside of the latch with grease from portion (1).

REMARK
If there is no more grease inside the latch, the movement of the door will become poor because of dust inside
the latch, and the handle may become heavy when you open the door.

Examine Door Lock Striker

Measure wear (A) of the door lock striker.
If wear (A) is 0.5 mm {0.02 in} or more, replace the door lock
striker.
If you use it as it is, its play increases and can cause breakage
of the hinge and lock door.

4-42
Maintenance Maintenance Procedure

How to Examine Window Washer Fluid Level, Add Fluid

Perform this check when no window washer fluid comes out.
1. Open the hydraulic tank inspection cover.
2. Check the fluid level in window washer tank (1).
If the fluid level is low, remove cap (2) and add window
washer fluid for automobile through the filler port.
Be careful not to let dirt or dust get in when adding fluid.

(Mixture ratio of pure washer fluid and water)

The proper mixing proportion varies with the ambient temperature. Add washer fluid diluted with water at the
following proportion.
Area, season Mixing proportion Freezing temperature
Normal Washer fluid 1/3: water 2/3 -10 °C {14 °F}
Winter in cold district Washer fluid 1/2: water 1/2 -20 °C {-4 °F}
Winter in extremely cold district Pure washer fluid -30 °C {-22 °F}

There are 2 types depending on the freezing temperature: -10 °C {14 °F} (general use) and -30 °C {-22 °F}
(cold district use), select according to the area and season.

4-43
Maintenance Procedure Maintenance

How to Examine Wiper Blade

(1) Front wiper (4) Wiper arm

(2) Rear wiper (5) Wiper blade
(3) Door wiper
Check each wiper visually, and replace the wiper blade in the following cases.
• When wiping is uneven
• When the wiper blade has cracks or damages
• When the wiped glasses has rubber abrasion of the wiper blade
NOTICE
Be careful not to release the arm by mistake while the blade is being removed from the arm. Otherwise it
may hit the glass and the glass may be broken.
If the glass has rubber abrasion of the wiper blade, remove it with a plastic scraper or by using a cloth, etc. with
a neutral detergent.
Do not use any solvent to remove it, because it has a bad influence upon the wiper blade rubber.

Replace Wiper Blade

If the blade is damaged, it will not wipe the window clean, so
replace the blade.

Replace Front Wiper

1. Loosen screw (1), and remove the blade.
2. Install the new blade, and tighten screw (1).
Tightening torque: 2.5 to 3 Nm {0.26 to 0.31 kgfm, 1.88 to
2.24 lbft}

4-44
Maintenance Maintenance Procedure

Replace Rear Wiper

The rear wiper is hooked at portion (A).
1. Move the blade in the direction of the arrow.
The blade comes off.
2. Install the new blade and hook it securely.

Replace Door Wiper

The front wiper is hooked at portion (A).
1. Move the blade in the direction of the arrow.
The blade comes off.
2. Install the new blade and hook it securely.

4-45
Maintenance Procedure Maintenance

How to Examine and Do Maintenance Air Conditioner

How to Examine Air Conditioner Compressor Belt Tension
1. Open the engine side cover (1) on the left side of the ma-
chine.

2. Remove the bolts (2) (6 pieces) and remove the cover (3).

3. Remove the bolts (4) (2 pieces).

4. Remove the bolts (5) (2 pieces) and remove the cover (6).

4-46
Maintenance Maintenance Procedure

5. Press the middle point between the compressor pulley (7)

and idler pulley (8) with your finger (approximately 98 N
{10 kgf}).
If deflection (A) is 11.5 to 14.5 mm {0.45 to 0.57 in}, the
belt tension is normal.
If the deflection is out of the standard range, adjust it into
the standard range.

4-47
Maintenance Procedure Maintenance

How to Adjust Air Conditioner Compressor Belt Tension

Prepare a bar.
1. Remove the bolts (1) (6 pieces) and remove the cover (2).

2. Loosen the bolts (3) (4 pieces).

3. Loosen the lock nut (4), tighten the adjustment bolt (5),
and adjust the belt tension.
4. After adjustment, tighten the lock nut (4), and tighten the
bolt (3).
5. Check each pulley for breakage and wear of the V-groove
and check the V-belts for wear.
In particular, check carefully that the V-belt is not in contact
with the V-groove bottom.
6. Replace the belt with a new one if the belt is stretched and
has no allowance for adjustment, or has slipping sound or squeak because of cuts or cracks of the belt.
Ask your Komatsu distributor for replacement of the belt.
When it has been replaced with a new part, there will be initial elongation. After 2 or 3 days of operation,
adjust it again.
7. Install the cover (2).

4-48
Maintenance Maintenance Procedure

How to Examine Refrigerant (Gas) Level

k WARNING
• Be sure to handle the refrigerant (gas) according to the local regulations.
• If the refrigerant used in the air conditioner gets into your eyes or is splashed on your hands, it may
cause loss of sight or frostbite. Never touch the refrigerant. Do not loosen any part of the refrigerant
circuit.
• Do not bring any open flame close to any point where the refrigerant gas is leaking.

The sight glass (inspection window) is located on the pillar at

the rear left of the machine.
Check the refrigerant gas (Hydrofluorocarbons HFC -134a)
condition with the sight glass (inspection window) of the receiv-
er while the air conditioner is in operation.

(A) Blue: The air conditioner is operated normally.

(B) Pink: The receiver drier needs to be replaced.
If the sight glass (inspection window) is pink, contact your Ko-
matsu distributor for repair.

REMARK
The bubbles or condensation may be generated in the sight glass (inspection window), however, it does not in-
dicate that the refrigerant level is low. It is normal when Hydrofluorocarbons HFC -134a is used. Do not add the
refrigerant gas.

How to Examine During Off Season

Even during the off-season, operate the air conditioner for 3 to 5 minutes once a month to maintain the oil film at
all parts of the compressor.

4-49
Maintenance Procedure Maintenance

How to Bleed Air from Hydraulic Circuit

Bleed air from the circuit after the filter element or strainer, etc. has been replaced or cleaned.
Since the engine must be started and the blade must be operated, see OPERATION.
1. Bleed air from the pump according to the following procedure.
NOTICE
Abnormal heat will be generated if the pump is operated without filling the pump case with hydraul-
ic oil. It may cause a premature damage to the pump. Be sure to bleed the air.
1) Remove the cap of oil filler port (F) at the top of the
hydraulic tank.
2) Remove the floor mat (1) and floor plate (2).
3) Loosen the air bleeders (3) and (4) installed to the
drain port and check that oil oozes out from them.
4) After bleeding air, tighten the air bleeder (3).
Tightening torque: 11.8 to 14.7 Nm {1.2 to 1.5 kgfm,
8.68 to 10.8 lbft}
5) Close the cap of oil filler port (F) at the top of the hy-
draulic tank.
2. Bleed air from the cylinder according to the following pro-
cedure.
NOTICE
If the engine runs at high speed immediately after the
startup, or if a cylinder is pushed up to its stroke end,
the air mixed into the cylinder may cause damage to
the piston packing, etc.
1) Start the engine.
2) Run the engine at low idle.
Keep the engine running at low idle for 10 minutes af-
ter starting, and then start the following work.
3) Operate each cylinder of the work equipment to ap-
proximately 100 mm {3.9 in} before the stroke end 4
to 5 times.
At this time, take care not to operate the cylinder to
the stroke end.
4) Run the engine at high idle (max. speed).
5) Operate each cylinder of the work equipment to ap-
proximately 100 mm {3.9 in} before the stroke end 4
to 5 times.
At this time, take care not to operate the cylinder to
the stroke end.
6) Run the engine at low idle and operate each cylinder 4
to 5 times to the stroke end to bleed the air complete-
ly.
3. After completing the air bleeding, stop the engine, leave
the machine as it is for at least 5 minutes, and then start
the operation.
The air bubbles in the oil inside the tank are discharged.
4. Check that there is no leakage of oil and wipe off any oil that is spilled.

4-50
Maintenance Maintenance Procedure

Procedure to Release Internal Pressure in Hydraulic Circuit

k WARNING
• The hydraulic system is always under internal pressure. Before checking or replacing the pipes and
hoses, release the pressure from the circuit. If the internal pressure has not been released, the high
pressurized oil may spout out and it may cause serious personal injury or death.
• Immediately after the engine is stopped, its parts and oil are still very hot and may cause burn in-
jury. Wait for the temperature to go down, and then start the work.
• If the oil filler cap is removed without releasing the internal pressure, oil will spurt out, so turn the
oil filler cap slowly to release the internal pressure, then remove it carefully.

NOTICE
Finish the steps of operating the blade control lever fully forward and backward, and to the right and left
within 15 seconds after the engine has stopped.
1. Stop the machine.
Place the machine on a firm, level ground.
2. Lower the work equipment to the ground and stop the engine.
3. Turn the starting switch to ON position.
4. Set the work equipment lock lever to FREE position.
5. Operate the blade control lever fully forward, backward, to the right, and left to release the pressure from
the hydraulic circuit.
6. Set the work equipment lock lever to LOCK position.
7. Loosen oil filler cap (F) slowly on the top of the hydraulic
tank to release the internal pressure in the hydraulic tank.

How to Examine Electrical Intake Air Heater

Check before starting in the cold weather (once a year).
Ask your Komatsu distributor for check of the electrical intake air heater.

4-51
Maintenance Procedure Maintenance

Adjust Shim of Center Ball

k WARNING
Place the work equipment lock lever at LOCK position except when operating the blade for adjustment.

The shim adjustment of the center ball portion is required in the following cases.
• When a play is found at the center ball portion
• When the blade is assembled again after it has been removed for transportation
If it is not adjusted, the blade response to the operation becomes worse, and soil and sand enter and cause
premature wear or damage of the ball.
Adjust as follows.
• Correct value for play at ball joint0.2 to 0.7 mm {0.008 to 0.028 in}
• Standard shim thickness6 to 8 mm {0.236 to 0.315 in}
1. Remove the bolt (1) and loosen the bolts (2) (5 pieces).
2. Remove all the shims (3) and tighten the bolts (1) and (2)
lightly so that the dimension of clearance (A) becomes
even at whole circumference.
3. Measure the clearance (A) and set the shim thickness so
that it is between (A + 0.2) and (A + 1.2) mm {(A + 0.008)
and (A + 0.047) in} .
The shim thickness can be set by removing some shims
from the number of shims to use.
Shim thickness (number of shims to use): 0.5 mm {0.02 in}
(2 pieces), 1.0 mm {0.039 in} (8 pieces)
4. Restore the shims of the thickness which is set in step 3 to
the original position, and tighten the bolts (1) and (2) light-
ly.
5. Angle and tilt the blade to check the play at center ball por-
tion.
• When no creak sound is heard and the blade moves
smoothly, the adjustment is completed.
• If a creak sound is heard or the blade does not move
smoothly, add shims.
• If the play at the ball portion is still large, remove more shims.
6. After adjusting, tighten the bolts (1) and (2).
Tightening torque: 455 to 565 Nm {46.5 to 58 kgfm, 336 to 420 lbft}

4-52
Maintenance Maintenance Procedure

How to Adjust Shims at Pitch Ball

k WARNING
Place the work equipment lock lever at LOCK position except when operating the blade for adjustment.

The shim adjustment of the pitch ball portion is required in the following cases.
• When a play is found at the pitch ball portion
• When the blade is assembled again after it has been removed for transportation
If it is not adjusted, the blade response to the operation becomes worse, and soil and sand enter and cause
premature wear or damage of the ball.
Adjust as follows.
• Correct value for play at ball joint0.2 to 0.7 mm {0.008 to 0.028 in}
• Standard shim thickness3 to 5 mm {0.118 to 0.197 in}
1. Remove the bolt (1) and loosen the bolt (2).
2. Remove all the shims (3) and tighten the bolts (1) and (2)
lightly so that the dimension of clearance (A) becomes
even at whole circumference.
3. Measure the clearance (A) and set the shim thickness so
that it is between (A + 0.2) and (A + 1.2) mm {(A + 0.008)
and (A + 0.047) in} .
The shim thickness can be set by removing some shims
from the number of shims to use.
Shim thickness (number of shims to use): 0.5 mm {0.02 in}
(2 pieces), 1.0 mm {0.039 in} (4 pieces)
4. Restore the shims of the thickness which is set in step 3 to
the original position, and tighten the bolts (1) and (2) light-
ly.
5. Angle and tilt the blade to check the play at pitch ball por-
tion.
• When no creak sound is heard and the blade moves
smoothly, the adjustment is completed.
• If a creak sound is heard or the blade does not move
smoothly, add shims.
• If the play at the ball portion is still large, remove more shims.
6. After adjusting, tighten the bolts (1) and (2).
Tightening torque: 823 to 1029 Nm {84 to 105 kgfm, 608 to 759 lbft}

4-53
Maintenance Procedure Maintenance

Examine Before You Start Operation

For the following items, see OPERATION, “METHOD FOR CHECKING BEFORE STARTING”.
• Method for draining water and sediment from fuel tank
• Method for checking water separator, draining water and sediment
• Method for checking oil level in hydraulic tank, adding oil
• Method for checking coolant level, adding coolant
• Method for checking oil level in engine oil pan, adding oil
• Method for checking dust indicator
• Method for checking electric wiring
• Method for checking fuel level, adding fuel
• Method for checking DEF level, adding DEF
• Method for checking lamps operation
• Method for checking machine monitor
• Method for removing deposit in engine compartment
• Method for checking horn operation
• Method for checking backup alarm operation status
• Method for testing decelerator/brake pedal

4-54
Maintenance Maintenance Procedure

Every 50 Hours Maintenance

Lubrication
NOTICE
Perform the lubrication every 10 hours when the machine is operated on the soft ground, etc., and the
soil and sand are accumulated on the machine.
1. Lower the blade to the ground and stop the engine.
When lubricating the lift cylinder bottom pin (1) and U-frame mounting pin (3), lower the blade to raise the
idler 1 to 2 cm {0.4 to 0.8 in} from the ground, then stop the engine.
2. By using a grease pump, pump in grease through the grease fitting.
3. After greasing, wipe off any old grease that is pushed out.
(1) Lift cylinder bottom pin (1 place each of right and left)
(2) Lift cylinder head pin (1 place each of right and left)
(3) U-frame mounting pin (1 place each of right and left)
(4) Angle cylinder bottom pin (1 place each of right and
left)

(5) Center ball pin (1 place)

(6) Pitch rod pin (1 place)
(7) Pitch rod ball (1 place)

How to Lubricate Equalizer Bar Center Pin

(1 place)
1. Clean the grease fitting shown by arrow.
2. By using a grease pump, pump in grease through the
grease fittings.
If the lever of the grease pump does not move smoothly,
supply grease according to the following procedure.
1) Lower the blade until the idler is raised 1 to 2 cm {0.4
to 0.8 in} above the ground.
2) Tilt the blade from side to side with it lowered, and
move the equalizer bar.
3) Perform the procedure in step 2) several times, and
supply grease again by using the grease pump.
If the greasing still can not be performed, move the machine forward and reverse as much as you can,
and then perform the steps 1) to 3).

4-55
Maintenance Procedure Maintenance

Every 250 Hours Maintenance

Maintenance for every 50 hours service should be performed at the same time.

Lubrication
NOTICE
Perform the lubrication every 10 hours when the machine is operated on the soft ground, etc., and the
soil and sand are accumulated on the machine.
1. Lower the blade to the ground and stop the engine.
2. By using a grease pump, pump in grease through the grease fittings.
3. After greasing, wipe off any old grease that is pushed out.
(1) Angle cylinder head pin (1 place each of right and left)
(2) Tilt cylinder bottom pin (1 place)

(3) Tilt cylinder head pin (1 place)

How to Lubricate Equalizer Bar Side Pin

(1 place each on right and left sides)
1. Remove all soil and sand from the top of the track frame
and top of the cover.
2. Clean the grease fitting shown by arrow.
3. Supply grease by using a grease pump.
REMARK
• Supply 3 shots of grease (Operate the grease pump
lever 3 times) to each grease fitting, and check that
grease is newly discharged through the seal lip.
• If grease is not newly discharged through the lip por-
tion, continue supplying grease until it is discharged.
• If the blade is lowered to raise the idler 1 to 2 cm {0.4
to 0.8 in} from the ground in order when performing
lubrication, the grease will fill the whole circumference
of the pin.

4-56
Maintenance Maintenance Procedure

How to Examine Oil Level in Final Drive Case, Add Oil

k WARNING
• Immediately after the engine is stopped, its parts and oil are still very hot and may cause burn in-
jury. Wait for the temperature to go down, and then start the work.
• If there is remaining pressure inside the case, the oil or plug may jump out. Loosen the plug slowly
to release the pressure.

Prepare a handle for the work.

1. Stop the machine so that the TOP mark comes on the top
while a line between TOP mark and plug (P) becomes per-
pendicular to the ground surface.
2. Remove plug (F) by using a handle, and check the oil lev-
el.
• When the oil level is near the lower edge of plug (F)
hole
The oil level is proper.
• When the oil level is far below the lower edge of plug
(F) hole
The oil is insufficient.
Add oil until it overflows from plug (F) hole.
3. Install plug (F).
Tightening torque: 58.8 to 78.4 Nm {6 to 8 kgfm, 43.4 to
57.8 lbft}

4-57
Maintenance Procedure Maintenance

How to Examine Battery Electrolyte Level

k WARNING
• Do not use the battery if the battery electrolyte level is below LOWER LEVEL line. If you do so, it will
reduce the service life of the battery. In addition, it may cause an explosion.
• Since the battery produces combustible gas, it can explode. Do not bring any open flame close.
• Battery electrolyte is dangerous object. Also, take care that it does not stick your eye or skin. If bat-
tery electrolyte sticks to your skin, wash it away with large amounts of water, then get medical at-
tention.
• Do not add the electrolyte to the battery exceeding UPPER LEVEL line. It may leak and cause dam-
age to the paint surface or corrode other parts.
• Do not use a direct air blow or dry cloth to clean the battery. A wet cloth will prevent fire or explo-
sion from static electricity.

NOTICE
If there is a fear that the battery water may freeze after refilling with purified water (such as a commer-
cial battery fluid), do the replenishment before the day's work on the next day.
Perform this procedure before operating the machine.
Inspect the battery electrolyte level at least once a month.

How to Examine Electrolyte Level from Side of Battery

If it is possible to check the electrolyte level from the side of the battery, check as follows.
1. Open the hydraulic tank inspection cover on the left side of the machine.
2. Clean around the electrolyte level line with a cloth wet with water.
3. Check the electrolyte level.
• When the electrolyte level is between UPPER LEVEL
(U.L.) line and LOWER LEVEL (L.L.) line.
The battery electrolyte level is proper.
• When the electrolyte level is below the center line be-
tween UPPER LEVEL (U.L.) line and LOWER LEVEL
(L.L.) line.
The battery electrolyte level is low. Add purified water
according to the following procedure.

1) Remove the plastic sheet (1) installed above the bat-

tery.

4-58
Maintenance Maintenance Procedure

2) Remove cap (2) immediately and add purified water

(example: commercially available battery liquid) up to
UPPER LEVEL (U.L.) line.
3) After adding the purified water, tighten cap (2) secure-
ly.

REMARK
If purified water is added to above U.L. line, use a syringe to lower the level to U.L. line. Neutralize the removed
fluid with baking soda (sodium bicarbonate), then flush it away with a large amount of water. If necessary, con-
sult your Komatsu distributor or a battery manufacturer.

4-59
Maintenance Procedure Maintenance

How to Examine Electrolyte Level When It is Not Possible to Examine from Side
of Battery
If it is impossible to check the electrolyte level from the side of the battery, or there is no UPPER LEVEL line on
the side of the battery, check as follows.
1. Open the hydraulic tank inspection cover on the left side of the machine.
2. Remove the plastic sheet (1) installed above the battery.

3. Remove caps (2) from the top of the battery.

4. Look into fluid filler port (3) and check the electrolyte level.
(A) Correct level: Electrolyte level is up to bottom of
sleeve, so surface tension causes electrolyte surface to
bulge and pole plate appears to be warped.
(B) Low: Electrolyte level is not up to bottom of sleeve, so
poles appear straight and not bent.
If the electrolyte does not reach sleeve (4), always add the
purified water (such as a commercial battery fluid) so that
the level reaches the bottom of sleeve (4) (UPPER LEV-
EL).
5. After checking adding the purified water, tighten cap (2)
securely.

REMARK
If the purified water is added to above the bottom of sleeve (4), use a syringe to remove electrolyte to the bot-
tom of sleeve (4). Neutralize the removed fluid with baking soda (sodium bicarbonate), then flush it away with a
large amount of water. If necessary, consult your Komatsu distributor or a battery manufacturer.

How to Examine Electrolyte Level When It is Possible to Use Indicator to Exam-

ine Electrolyte Level
If it is possible to use an indicator to check the electrolyte level, follow the instructions given.

4-60
Maintenance Maintenance Procedure

How to Examine Brake Performance Curve

k WARNING
If the machine moves off during the following operation, ask your Komatsu distributor for repairs imme-
diately.

Before starting the engine, check the safety around the machine, and then perform the following operation.
1. Turn the starting switch key to START position (C).
The engine starts.

2. Be sure to operate the lock lever (1) by the red portion on

the top, then set it to FREE position (F).
3. Operate blade control lever (2) to float the blade.
Leave work equipment lock lever (1) in FREE position (F).

4. Operate the parking brake lever (3) by holding the operat-

ing portion on the top, and place the lever in FREE posi-
tion (F)

5. Depress decelerator/rake pedal (4) and set joystick (steer-

ing, directional and gear shift lever) (5) to the forward.
6. Operate fuel control dial (6) and gradually raise the engine
speed to full throttle.
7. Check that the machine can move or that the warning
screen is displayed on the machine monitor.
• When the machine cannot move and the warning
screen is not displayed on the machine monitor.
The brake is normal.
• When the machine can move or the warning screen is
displayed on the machine monitor.
Immediately ask your Komatsu distributor for repair.

4-61
Maintenance Procedure Maintenance

Every 500 Hours Maintenance

Maintenance for every 50 and 250 hours should be performed at the same time.

Change Oil in Final Drive Case

k WARNING
• Immediately after the engine is stopped, its parts and oil are still very hot and may cause burn in-
jury. Wait for the temperature to go down, and then start the work.
• If there is remaining pressure inside the case, the oil or plug may jump out. Loosen the plug slowly
to release the pressure.

Refill capacity: each of right and left 5.5 ℓ {1.45 U.S.Gal}

Prepare a handle, and a container to catch the drained oil.
1. Stop the machine so that the TOP mark comes on the top
while a line between TOP mark and plug (P) becomes per-
pendicular to the ground surface.
2. Place the oil container to catch oil under plug (P).
3. Remove plugs (P) and (F) by using the handle, and drain
oil.
4. Check O-rings attached to plugs (P) and (F) for damage. If
necessary, replace them with new ones.
5. After draining the oil, tighten plug (P).
6. Add oil until it overflows from plug (F) hole.
7. Install plug (F).
Tightening torque for plugs (P) and (F): 58.8 to 78.4 Nm {6
to 8 kgfm, 43.4 to 57.9 lbft}

How to Change Oil in Engine Oil Pan and Replace Engine Oil Filter Cartridge
k WARNING
Immediately after the engine is stopped, its parts and oil are still very hot, and may cause burn injury.
Wait for the temperature to go down, and then start the work.

Refill capacity: 15.5 ℓ {4.1 U.S.Gal}

Prepare a socket wrench and a filter wrench.
Prepare a container to catch the drained oil.

4-62
Maintenance Maintenance Procedure

1. Remove the cover (1).

2. Pull out the hose (2).

3. Place the oil container to receive the oil under the hose.
4. Loosen the drain plug (P) to drain oil. Do it slowly so that
you do not get splashed with the drained oil.
5. Tighten the drain plug (P).
6. Check the drained oil.
If there are excessive metal particles or foreign material,
contact your Komatsu distributor.
7. Install the cover (1).
8. Remove the mounting bolts (6 pieces) from engine side
cover (3) on the right side of the machine, and remove the
engine side cover (3).

9. Turn the engine oil filter cartridge (4) counterclockwise to

remove by using the filter wrench.
10. Clean the filter head.
11. Fill the new filter cartridge with clean oil, coat the packing
face and thread portion with oil (or coat thinly with grease),
then install the filter cartridge.
12. After the packing surface reaches the filter head, tighten
the new filter cartridge 3/4 to 1 turn.

4-63
Maintenance Procedure Maintenance

13. After replacing the filter cartridge, open the engine side
covers (5) and (6) on the left side of the machine.

14. Add oil through the oil filler port (F) until the oil level is be-
tween H and L marks on dipstick (G).
15. Run the engine at low idle for a while and then stop it.
16. Check that the oil level is between H and L marks on the
dipstick.
• When the oil level is below the mark L
The oil is insufficient. Add oil through the oil filler port
(F).
17. After the replacement is completed, install the engine side
cover (3), and close the engine side covers (5) and (6).

REMARK
When the ambient temperature is low, water or emulsified matter may stick to the dipstick, oil filler cap, etc. or
the drained oil may be milky white because of water vapor in the blowby gas. However, if the coolant level is
normal, it is not a problem.
There is no problem even if the emulsified matter cannot be removed completely after changing the oil.

4-64
Maintenance Maintenance Procedure

How to Replace Fuel Prefilter Cartridge

k WARNING
• Just after the engine stops, all parts are still very hot, so do not replace the filter immediately. Wait
for all parts to cool down before starting the work.
• While the engine is running, high-pressure is generated in the engine fuel piping.
When replacing the filter, wait for at least 30 seconds after stopping the engine to let the internal
pressure go down before replacing the filter.
• Do not bring any open flame close.

NOTICE
• Komatsu genuine fuel filter cartridges use a special filter that has highly efficient filtering ability.
When replacing the parts, Komatsu recommends using Komatsu genuine parts.
• The common rail fuel injection system used on this machine consists of more precise parts than
those in the conventional injection pump and nozzles. If any cartridge other than a Komatsu genu-
ine filter cartridge is used, dust or dirt may get in and cause problems with the injection system.
Never use a substitute.
• When performing the inspection or maintenance of the fuel system, pay more attention than normal
to the entry of dirt. If dirt sticks to any part, use fuel to wash it off completely.
Prepare a filter wrench and a container to catch the fuel.
1. Open the fuel tank inspection cover on the right side of the
machine.
2. Turn the fuel supply valve (1) to CLOSE position (C).

3. Pass the drain hose (2) through the hole of the tank bot-
tom plate.
4. Place a container to catch fuel under the drain hose (2).

5. Loosen the drain valve (3) and drain the water and sedi-
ments from the transparent cup (4), and also drain all the
fuel from the filter cartridge (5).
6. Turn the transparent cup (4) counterclockwise to remove it
by using the filter wrench.
This cap is used again. If the cap is damaged, replace it
with a new one.
7. Turn the filter cartridge (5) counterclockwise by using the
filter wrench, and remove it.
8. Install the removed transparent cup (4) to the bottom of the
new filter cartridge.

4-65
Maintenance Procedure Maintenance

At this time, be sure to replace the O-ring with a new one.

When replacing the O-ring, coat the surface with clean fuel before installing it.
9. After the packing surface touches the seal surface of the filter cartridge, tighten the transparent cup (4) 1/4
to 1/2 turn.
REMARK
If the transparent cup is fastened too much, the O-ring will be damaged and this leads to leakage of fuel. If
it is too loose, fuel will also leak from gaps of the O-ring. Be sure to observe the tightening angle.
10. Clean the filter head.
11. Fill the new filter cartridge with clean fuel, thinly apply oil to the packing surface, then install it to the filter
head.
NOTICE
• When filling the filter cartridge with fuel, do not re-
move the cap (B) at center. Always fill with fuel
from the small holes (A) (8 places) on the dirty
side.
• After filling with fuel, remove the cap (B) at center
and install the fuel filter.
• Always fill with clean fuel. Be careful not to let any
dirt or dust get into the fuel. In particular, center
portion is the clean side, so do not remove the cap
(B) when filling with fuel. Be careful not to let dirt
or dust get into the center portion on the clean
side.
12. After the packing surface reaches the sealing surface of the filter head, tighten the filter cartridge 3/4 turns.
REMARK
• If the filter cartridge is fastened too much, the packing will be damaged and this leads to leakage of
fuel. If the filter cartridge is too loose, fuel will also leak from the packing. Be sure to observe the tight-
ening angle.
• When tightening by using a filter wrench, be extremely careful not to dent or damage the filter.
13. Confirm that the drain valve (3) at the bottom of the transparent cup (4) is tightened securely.
14. Turn the fuel supply valve (1) to OPEN position (O).
15. Bleed the air.
1) Fill up the fuel tank with fuel (to the level where the
float is at the highest position).

2) Loosen the knob of feed pump (6), pull it out, then

pump it in and out until the movement becomes
heavy.
REMARK
• It is not necessary to remove the plugs at the fuel
prefilter head and at the fuel main filter head.
• When the engine runs out of fuel, use the same
procedure to operate the feed pump (6) and bleed
the air.

4-66
Maintenance Maintenance Procedure

3) After bleeding air, push in the knob of feed pump (6) and tighten it.
16. Turn the starting switch key to START position (C) and
start the engine.
17. Check the filter seal surface and the mounting face of the
transparent cup for fuel leakage.
If there is any leakage of fuel, check the tightening condi-
tion of the filter cartridge.
If the fuel still leaks, remove the filter cartridge again, and
check the packing surface for damage or foreign material.
If the packing surface is damaged or there is any foreign
material on it, replace the filter cartridge with a new one,
install the filter cartridge according to the preceding procedure, and then bleed air from the fuel circuit.
18. Run the engine at low idle for approximately 10 minutes.
19. After the replacement is completed, close the fuel tank inspection cover.

4-67
Maintenance Procedure Maintenance

Replace Air Conditioner Fresh/Recirc Air Filters

Since the filtering ability of the filters decreases as they are aged, replace them every 500 operating hours or
every year.

Replace Recirculation Air Filter

1. Turn knob (1) at the back of the operator's seat, and re-
move recirculation air filter (2).
2. Install the new recirculation air filter (2), and tighten knob
(1).
When fixing it with knob, check the filter position by touch-
ing it with hands or looking at it, and then tighten it.

Replace Fresh Air Filter

1. Turn knob (1) to open the inspection cover at the rear of
the machine, and remove the fresh air filter.
2. Install the new fresh air filter, and tighten knob (1).
REMARK
When the inside of the filter case is dirty, clean it before in-
stalling the filter.

4-68
Maintenance Maintenance Procedure

How to Examine Electric Wiring Around Starting Motor and Alternator

k CAUTION
If there are traces of short-circuiting on the electric wiring, immediately ask your Komatsu distributor to
locate the cause of it and to perform the repair.

1. Remove the engine side cover (1) on the right side of the
machine.

2. Remove the cover (2) under the engine side cover on the
left side of the machine.
3. Perform the following check.
• Check that there is no disconnection or trace of short-
circuiting in the electric wiring and no damage to the
coating.
• Check that there is no loose terminals, and retighten
any loose parts if found.
4. Install the cover (2) under the engine side cover on the left
side of the machine.
5. Install the engine side cover (1) on the right side of the machine.

4-69
Maintenance Procedure Maintenance

Every 1000 Hours Maintenance

Maintenance for every 50, 250 and 500 hours should be performed at the same time.

4-70
Maintenance Maintenance Procedure

How to Replace Fuel Main Filter Cartridge

k WARNING
• Just after the engine stops, all parts are still very hot, so do not replace the filter immediately. Wait
for all of parts to cool down before starting the work.
• High pressure is generated inside the engine fuel piping system when the engine is running.
When replacing the filter, wait for at least 30 seconds after stopping the engine to let the internal
pressure go down before replacing the filter.
• Do not bring any open flame close.

NOTICE
• Komatsu genuine fuel filter cartridges use a special filter that has highly efficient filtering ability.
When replacing the parts, Komatsu recommends using Komatsu genuine parts.
• The common rail fuel injection system used on this machine consists of more precise parts than
those in the conventional injection pump and nozzles. If any cartridge other than a Komatsu genu-
ine filter cartridge is used, dust or dirt may get in and cause problems with the injection system.
Never use a substitute.
• When performing the inspection or maintenance of the fuel system, pay more attention than normal
to the entry of dirt. If dirt sticks to any part, use fuel to wash it off completely.
Prepare a filter wrench and a container to catch the fuel.
1. Open the fuel tank inspection cover on the right side of the
machine.
2. Turn the fuel supply valve (1) to CLOSE position (C).

3. Open the engine side cover (2) on the left side of the ma-
chine.

4. Place a container under filter cartridge (3) to catch the fuel.

5. Turn the filter cartridge (3) counterclockwise by using the
filter wrench, and remove it.

4-71
Maintenance Procedure Maintenance

NOTICE
• Do not fill the new filter cartridge with fuel.
• Remove the cap (B) at center and install the filter car-
tridge.

6. Clean the filter head.

7. Thinly apply the oil to the packing surface of the new filter cartridge, then install the filter cartridge to the
filter head.
8. Replace inner seal (4) with a new one.
9. After the packing surface reaches the sealing surface of
the filter head, tighten the filter cartridge 3/4 turns.
REMARK
If the filter cartridge is fastened too much, the packing will
be damaged and this leads to leakage of fuel. If the filter
cartridge is too loose, fuel will also leak from the packing.
Be sure to observe the tightening angle.

10. Turn the fuel supply valve (1) to OPEN position (O).
11. Bleed the air.
1) Fill up the fuel tank with fuel (to the level where the
float is at the highest position).

2) Loosen the knob of feed pump (5), pull it out, then

pump it in and out until the movement becomes
heavy.
REMARK
• It is not necessary to remove the plugs at the fuel
prefilter head and at the fuel main filter head.
• When the engine runs out of fuel, use the same
procedure to operate the feed pump (5) and bleed
the air.
3) After bleeding air, push in the knob of feed pump (5)
and tighten it.

4-72
Maintenance Maintenance Procedure

12. Turn the starting switch key to START position (C) and
start the engine.
13. Check the filter seal surface and the mounting face of the
transparent cup for fuel leakage.
If there is any leakage of fuel, check the tightening condi-
tion of the filter cartridge.
If the fuel still leaks, remove the filter cartridge again, and
check the packing surface for damage or foreign material.
If the packing surface is damaged or there is any foreign
material on it, replace the filter cartridge with a new one,
install the filter cartridge according to the preceding procedure, and then bleed air from the fuel circuit.
14. Run the engine at low idle for approximately 10 minutes.
15. After the replacement is completed, close the engine side cover (2) and the fuel tank inspection cover.

4-73
Maintenance Procedure Maintenance

Replace Fuel Tank Breather Element

1. Remove nut (2) of breather assembly (1) on the top of the
fuel tank.
Use a tool when the nuts are so tight to remove.
2. Remove cover (3).
3. Replace breather element (4) with a new one.
4. Install cover (3) and nut (2).
Tightening torque: 10 to 14 Nm {1.0 to 1.4 kgfm, 7.23 to
13.7 lbft}

How to Examine All Tightening Points of Engine Intake Pipe Clamps

Ask your Komatsu distributor for checking the tightening of the clamps between the air cleaner - turbocharger -
aftercooler - engine.

Replace Hydraulic Tank Breather Element

1. Remove nut (2) of breather assembly (1) on the top of the
hydraulic tank.
Use a tool when the nuts are so tight to remove.
2. Remove cover (3).
3. Replace breather element (4) with a new one.
4. Install cover (3) and nut (2).
Tightening torque: 10 to 14 Nm {1.0 to 1.4 kgfm, 7.23 to
13.7 lbft}

4-74
Maintenance Maintenance Procedure

Replace DEF Tank Breather Element

k WARNING
Immediately after the engine is stopped, the parts are still very hot. Do not replace the element immedi-
ately. Wait for all of parts to cool down before starting the work.

NOTICE
• Komatsu recommends using Komatsu genuine parts for replacement parts.
• If the machine is operated without the DEF tank breather element attached, or with the element oth-
er than Komatsu genuine parts, foreign materials may enter the DEF pump and DEF injector which
will cause failure of the machine. Never operate the machine without the DEF tank breather element
attached, nor use the element other than Komatsu genuine parts.
• The DEF tank breather element cannot be flushed. Flushing or regenerating of it will degrade the
performance of element, and will cause the breakage of the DEF tank. Never reuse the DEF element.
• Always stop the engine and clean around the DEF tank before replacing.
• After the engine is stopped, the DEF system devices automatically purge the DEF in the DEF injec-
tor and DEF pump and return it to the DEF tank to prevent malfunction of the devices caused by
freezing of the DEF or deposition of urea.
After the engine is stopped, the devices are operated up to 7 minutes. Replace the element after the
DEF system devices stop.
• Improper assembly of the DEF tank breather element may cause leakage of the DEF. Replace the
element in the correct procedure.
1. Open DEF tank filler port cover.
For the opening and closing method of the cover, see “METHOD FOR OPENING AND CLOSING DEF
TANK FILLER PORT COVER”.
2. Remove the nut (2) of breather assembly (1) on top of the
DEF filler port.
Use a tool when the nuts are so tight to remove.
3. Remove cover (3).
4. Replace breather element (4) with a new one.
5. Install cover (3) and nut (2).
Tightening torque: 1.2 to 1.4 Nm {0.12 to 0.14 kgfm, 0.87
to 1.01 lbft}
6. Close the DEF tank filler port cover.

4-75
Maintenance Procedure Maintenance

Examine and Replace Alternator Drive Belt Tension and Replacing Alternator
Belt
• Special tools are required for checking the tension of the alternator drive belt and replacing it. Ask your Ko-
matsu distributor to perform this work.
• Since the auto-tensioner is installed, tension adjustment is not required.
Check the alternator drive belt.
If alternator drive belt shows the following conditions, it must be
replaced. Ask your Komatsu distributor to replace it.
• When vertical flaw (2) that crosses horizontal flaw (1) is
found.
• When part of the belt has tears (3).
REMARK
When only horizontal flaw (4) is found, replacement is not re-
quired.

Examine for Looseness of ROPS Mount Bolt

Check the bolts for looseness or damage.
Bolts (1) (4 pieces each of right and left): 1 piece is located un-
der the floor plate.
• When any bolt is loose
Tighten the bolt.
Tightening torque: 785 to 981 Nm {80 to 100 kgfm, 579 to
723 lbft}
• When any bolt is damaged
Replace the bolt with a Komatsu genuine part.

4-76
Maintenance Maintenance Procedure

How to Examine and Clean Fan

k WARNING
• When performing cleaning, there is a danger that dirt may scatter and cause personal injury. Wear
the protective equipment such as the protective eyeglasses and dust mask.
• When performing cleaning, always stop the engine and check that the fan is not rotating. If you
touch the fan when it is rotating, it will cause serious personal injury or death.

When the compressed air cannot be used, perform the cleaning according to the following procedure.
1. Remove the bolts (1) (2 pieces) on the lower part of the ra-
diator grille.

2. Pull the radiator grille backward and raise it upward.

Open the radiator grille to the fully opened position, check
that it is locked, and then release your hand.

3. Remove the bolts (2) (4 pieces) and remove the net (3).
4. Wipe off the soil and sand, snow, ice and such which are
stuck to the fan (4).

4-77
Maintenance Procedure Maintenance

5. Close the radiator grille according to the following proce-

dure.
1) Lift up the radiator grille, and push the lock releasing
bar (5) to the direction of arrow.
The lock is released.
2) Close the radiator grille.
6. Tighten the bolts (1) (2 pieces) on the lower part of the ra-
diator grille.

REMARK
• For opening and closing the radiator grille, see “METHOD FOR OPENING AND CLOSING RADIATOR
GRILLE”.
• For opening and closing the radiator grille of the machine equipped with ripper, see ATTACHMENTS AND
OPTIONS, “METHOD FOR OPENING AND CLOSING RADIATOR GRILLE”.

4-78
Maintenance Maintenance Procedure

Every 2000 Hours Maintenance

Maintenance for every 50, 250, 500 and 1000 hours service should be performed at the same time.

Change Oil in Hydraulic Tank, Replace Hydraulic Oil Filter Cartridge, Replace
HST Oil Filter Cartridge, and Clean Hydraulic Tank Strainer
k WARNING
• Immediately after the engine is stopped, its parts and oil are still very hot and may cause burn in-
jury. Wait for the temperature to go down, and then start the work.
• When the oil filler cap is removed, oil may spurt out. Turn the cap slowly to release the internal
pressure, then remove it carefully.
• Stop the engine, and turn the starting switch and the battery disconnect switch keys to OFF posi-
tions when handling the battery.

Refill capacity: 63 ℓ {16.6 U.S.Gal}

Prepare an oil container to receive the oil, a filter wrench, and hose.
Use a hose which can reach the container to receive the oil.
1. Lower the work equipment to the ground and stop the engine.
2. Loosen the cap of oil filler port (F) slowly on the top of the
hydraulic tank to release the internal pressure in the hy-
draulic tank.
3. Remove the cap.
4. Open the hydraulic tank inspection cover on the left side of
the machine.

5. Remove the grommet (1) at the lower part of the hydraulic

tank.

6. Remove the drain hose (2).

4-79
Maintenance Procedure Maintenance

7. Install the drain hose (2), which has been removed, to the
drain port (3), and pass it through the hole of the bottom
plate.

8. Place an oil container to catch the oil under the drain hose
(2).
9. Loosen the drain valve (4) and drain the oil.
When loosening the drain valve (4), be careful not to get
oil on yourself.
10. Tighten the drain valve (4).

11. Remove the cap (5) of the reservoir tank.

12. Remove the bolts (6) (3 pieces) and remove the reservoir
tank (7).

13. Remove the bolts (8) (4 pieces) of the suction flange.

14. Lift up the hose (9).

4-80
Maintenance Maintenance Procedure

15. Remove the screws (10) (2 pieces) of the suction flange.

16. Take out the strainer (11).

17. Remove the dirt, etc. from the strainer (11), then wash it in
the clean diesel fuel or flushing oil.
18. Install the strainer (11), and tighten it with screws (10) (2
pieces).
At this time, be sure to replace the O-ring (12) (strainer
side) with a new one and install it.
19. Install the suction flange with bolts (8) (4 pieces).
At this time, be sure to replace the O-ring (13) (suction
flange side) with a new one and install it.
20. Restore the reservoir tank (7) to the original position and install it with the bolts (6).
21. Install the cap (5) of the reservoir tank.
22. Place an oil container under the hydraulic oil filter.
23. Turn the hydraulic oil filter cartridge (14) counterclockwise
by using the filter wrench, and remove it.
24. Place a container to catch the drained oil under the hose
(2).
25. Clean the filter head.
26. Fill the new filter cartridge with clean oil, coat the seal and
thread portion of the new filter cartridge with oil (or apply
thin film of grease), then install it to the filter head.
27. After the packing surface touches the sealing surface of
the filter head, tighten the filter cartridge approximately 2/3 of a turn.
Komatsu recommends using Komatsu genuine cartridge.
28. Open the fuel tank inspection cover on the right side of the machine.
29. Turn the HST oil filter cartridge (15) counterclockwise to
remove by using the filter wrench.
30. Clean the filter head.
31. Fill the new filter cartridge with clean oil, coat the seal and
thread portion of the new filter cartridge with oil (or apply
thin film of grease), then install it to the filter head.
32. After the packing surface touches the sealing surface of
the filter head, tighten the filter cartridge approximately 2/3
of a turn.
Komatsu recommends using Komatsu genuine cartridge.
33. Add the refill capacity of oil through the oil filler port (F).
34. Install the cap of oil filler port (F).
35. Check that the oil level is proper.
36. Bleed air from the hydraulic circuit.

4-81
Maintenance Procedure Maintenance

For bleeding air, see “METHOD FOR BLEEDING AIR FROM HYDRAULIC CIRCUIT”.

4-82
Maintenance Maintenance Procedure

How to Examine Function of Accumulator for Control Circuit and Release Inter-
nal Pressure in Hydraulic Circuit
k WARNING
The accumulator is charged with high-pressure nitrogen gas, so improper operation may cause an ex-
plosion, which will lead to serious injury or death. For handling, always observe the following.
• The pressure in the hydraulic circuit cannot be completely removed. When removing the hydraulic
equipment, do not stand in the direction that the oil spurts out when performing the operation. In
addition, loosen the bolts slowly when performing the work.
• Do not disassemble it.
• Do not bring open flame close to it or do not dispose of it in fire.
• Do not perform drilling, welding or flame-cutting.
• Do not hit or roll it, or subject it to any impact.
• When disposing of it, the gas must be released. Ask your Komatsu distributor to have this work per-
formed.

NOTICE
If the nitrogen gas charge pressure in the accumulator is low and operations are continued, it becomes
impossible to release the remaining pressure inside the hydraulic circuit if a failure occurs on the ma-
chine.

Function of Accumulator
The accumulator (1) stores the pressure in the control circuit.
Even after the engine is stopped, the control circuit can be op-
erated, so the following actions are possible.
• If the control lever is operated in the direction to lower the
work equipment, it is possible for the work equipment to go
down under its own weight.
• The pressure in the hydraulic circuit can be released.

4-83
Maintenance Procedure Maintenance

Examine Accumulator Function

k CAUTION
When operating the blade control lever to lower the blade, check the safety around the machine.

NOTICE
If the nitrogen gas charge pressure in the accumulator is low and operations are continued, it becomes
impossible to release the remaining pressure inside the hydraulic circuit if a failure occurs on the ma-
chine.
Replace the accumulator every 2 years or every 4000 hours, whichever comes sooner.
Check the nitrogen gas charge pressure as follows.
1. Place the machine on a firm, level ground.
2. Operate the parking brake lever by holding the operating
portion on the top, and place the lever in LOCK position (L)

3. Raise the work equipment (blade) to the upper limit.

NOTICE
Perform the following procedure (for lowering the blade to the ground) within 15 seconds after stopping
the engine.
When the engine is stopped, the pressure inside the accumulator gradually goes down, so this inspec-
tion can be performed only immediately after the engine is stopped.
4. With the work equipment at the upper limit, turn the start-
ing switch to OFF position (A), and stop the engine.

4-84
Maintenance Maintenance Procedure

5. Turn the starting switch to ON position (B).

6. Be sure to operate the lock lever by holding the operating

portion on the top, then set it to FREE position (F).

7. Operate the blade control lever fully in the direction to low-

er the blade.

8. Check that the work equipment goes down to the ground

under its own weight.

In the following cases, the gas charge pressure of the accumulator has gone down. Contact your Komatsu dis-
tributor.
• Work equipment does not go down
• Stops while going down

How to Examine Alternator

Ask your Komatsu distributor to have the alternator checked.
If the engine is started frequently, have this inspection performed every 1000 hours.

How to Examine and Adjust Engine Valve Clearance

Special tools are necessary for inspection and maintenance. Ask your Komatsu distributor to perform this work.

4-85
Maintenance Procedure Maintenance

How to Examine Vibration Damper

Ask your Komatsu distributor for inspection of the vibration damper.

Replace KCCV Filter Element

k WARNING
Immediately after the engine is stopped, the parts are still very hot. Do not replace the element immedi-
ately. Wait for all parts to cool down before starting the work.

NOTICE
• Komatsu recommends using Komatsu genuine parts for replacement parts.
• If the engine is operated without the filter element, the turbocharger and aftercooler become dirty
and their performance will lower and that can cause engine problems such as overrun caused by
suction of oil. Therefore, do not start the engine without the filter element.
• The filter element cannot be cleaned. Flushing or regenerating of the filter element will degrade the
performance of the filter. As a result, the turbocharger and aftercooler become dirty and the per-
formance lowers or the crankcase pressure increases. Never reuse the filter element since it can
cause an engine failure.
• After the filter element is replaced, if KCCV is not assembled correctly, oil or blowby gas may leak.
Replace the filter element in the correct procedure.
• Always stop the engine and clean around the KCCV before replacing the element.
Prepare the special wrench for KCCV and a container to receive the oil.
1. Remove the engine side cover (1) on the right side of the
machine.

The KCCV ventilator is located in the position shown in the

figure.

4-86
Maintenance Maintenance Procedure

For the use of the special wrench, see the figure.

2. Loosen the ring (4) of KCCV ventilator (2) by using the

special wrench.

3. After the ring (4) comes off, remove the case (5) from body
(3), and remove the element (6).
There may be oil accumulated or sticking in the case and
element. Take care not to spill the oil when replacing the
element.
REMARK
When the ambient temperature is low, water or emulsified
matter may stick to the inside of KCCV because of con-
densation of water vapor in the blowby gas. However, as
far as the coolant level is normal, it is not a problem.
4. Remove the used O-ring (7) sticking to the case (5) and in-
stall a new O-ring contained in the service kit.
Apply the engine oil to the new O-ring.

4-87
Maintenance Procedure Maintenance

5. While matching ◇ marks (8) of the new element with ◇

mark (9) of the case, insert the element firmly into the end
of the body.
When inserting, take extreme care so that protrusion (10)
in the case is joined together with rubber lip (11) of the ele-
ment.

6. Align the position of ◇ mark (9) on the case with that of ◇

mark (12) of the filter body label, then install the case to
the filter body.
The element can be installed only when its claw (13) and
claw (14) of the case are correctly inserted in the groove
(15) of the body. Bases (16) and (17) are oval. Take ex-
treme care so that those bases are matched with each oth-
er.

7. Fit the ring (4) to the threaded part of the body and tighten
it with the hand firmly until it stops.

4-88
Maintenance Maintenance Procedure

8. Tighten the ring 1/15 to 2/15 turns further (1 to 2 ridges of

the ring) by using the special wrench.
If the engine is operated with the ring tightened insufficient-
ly, oil and blowby gas may leak.
9. Check the KCCV hose for leakage, crack, and loose
clamp.
Replace as necessary.

4-89
Maintenance Procedure Maintenance

Replace DEF Filter

k WARNING
Immediately after the engine is stopped, the parts are still very hot. Do not replace the filter immediately.
Wait for all of parts to cool down before starting the work.

NOTICE
• Komatsu recommends using Komatsu genuine parts for replacement parts.
• If the machine is operated without the DEF filter attached, or with the filter other than Komatsu gen-
uine parts, foreign materials may enter the DEF pump and DEF injector which will cause failure of
the machine. Never operate the machine without the DEF filter attached, nor use the filter other than
Komatsu genuine parts.
• The DEF filter cannot be flushed. Flushing or regenerating of it will degrade the performance of fil-
ter, and will cause the breakage of the DEF tank. Never reuse the filter.
• Improper assembly of the DEF filter may cause leakage of the DEF. Replace the DEF filter in the cor-
rect procedure.
• The DEF freezes at -11 °C {12.2 °F} . If it is frozen, replacement of the filter becomes difficult. Re-
place the filter when the temperature around the DEF pump is higher than -11 °C {12.2 °F} , and in
the condition that the DEF is not frozen.
After the engine is stopped, the DEF system devices automatically purge the DEF in the DEF injector and DEF
pump and return it to the DEF tank to prevent malfunction of the devices caused by freezing of the DEF or dep-
osition of urea.
After the engine is stopped, the devices are operated up to 7 minutes. Before replacing the filter, clean around
the DEF pump first after the DEF system devices stop.
Items to be prepared
• DEF filter removal tool
The DEF filter is located at the position shown in the figure.
Before replacing the DEF filter, remove the mounting bolts from
the following places, and remove the cover (A).
• Inside the DEF tank filler port cover, the mounting bolts (B)
(2 pieces)
• Left inside the hydraulic tank inspection cover on the left
side of the machine, the mounting bolts (C) (3 pieces)

4-90
Maintenance Maintenance Procedure

1. Remove the filter cap (1) at the bottom of the DEF pump,
and remove the equalizing element (2).

2. Turn the cap (4) of filter removal tool (3) and remove it.
3. Check the installation of spacer (5).

4. Insert the filter removal tool (3) into the bottom of the DEF
pump and thrust in by hand.

5. Check that the filter removal tool (3) is fully inserted to the
end.
Insert the filter removal tool to the end where you cannot
thrust it in any further.

6. Turn the filter removal tool (3) in reverse, and remove the
filter (6).
Filter (6) is removed and you can take it out together with
the filter removal tool (3).
If filter (6) cannot be removed from the DEF pump, grip the
filter removal tool (3), pull it down, then it will be removed.

4-91
Maintenance Procedure Maintenance

7. Slide the filter (6) down, and remove the spacer (5) from
the filter removal tool (3).

8. Pull the filter (6) up while pushing in the tip of filter removal
tool (3), and remove it.
9. Return the removed spacer (5) to the filter removal tool (3),
and keep them.
10. Insert a new filter and a new equalizing element into the
bottom of the DEF pump, and lightly tighten them by hand.

11. Tighten the filter cap (1).

Tightening torque: 20 to 25 Nm {2.0 to 2.5 kgfm, 14.5 to
18.1 lbft}

4-92
Maintenance Maintenance Procedure

Every 4000 Hours Maintenance

Maintenance for every 50, 250, 500, 1000 and 2000 hours service should be performed at the same time.

Replace Defined Life Parts

Material quality of these parts can change as time passes and they are likely to wear out or deteriorate.
Replace them every 2 years or every 4000 hours, whichever comes sooner.

Defined Life Parts List

No. Periodical replacement parts
1 Fuel system Fuel hose
2 Engine lubrication system Engine oil filter hose
3 Steering system High pressure circuit hose
4 Brake system Brake oil pressure hose
5 Torque converter, trans-
mission system (including Transmission circuit hose (including HST)
HST)
6 Work equipment hydraulic Work equipment pump delivery hose Ask your Komatsu distributor for
system replacement.
Work equipment pump LS hose
Hose for hydraulic drive fan
External work equipment hose
• Blade lift hose
• Blade tilt hose
• Blade angle hose
• Ripper lift hose
7 Others PPC accumulator

Examine Water Pump

Check around the water pump for water leakage.
If any abnormality is found, ask your Komatsu distributor for repair or replacement of the parts.

How to Examine Starting Motor

Consult your Komatsu distributor for inspection of the starting motor.
If you start the engine frequently, consult for inspection every 1000 hours.

4-93
Maintenance Procedure Maintenance

How to Replace Accumulator (For Control Circuit)

k WARNING
The accumulator is charged with high-pressure nitrogen gas, so mistaken operation may cause an ex-
plosion, which will lead to serious injury or death, or damage. For handling, always observe the follow-
ing.
• The pressure in the hydraulic circuit cannot be completely removed. When removing the hydraulic
equipment, do not stand in the direction that the oil spurts out when performing the operation. In
addition, loosen the bolts slowly when performing the work.
• Do not disassemble.
• Do not bring open flame close to it or do not dispose of it in fire.
• Do not perform drilling, welding or flame-cutting.
• Do not hit or roll it, or subject it to any impact.
• When disposing of it, the gas must be released. Ask your Komatsu distributor to have this work per-
formed.

NOTICE
If the nitrogen gas charge pressure in accumulator is low and operations are continued, it becomes im-
possible to release the remaining pressure inside the hydraulic circuit if a failure occurs on the ma-
chine.
Ask your Komatsu distributor to replace it.
Replace the accumulator (1) every 2 years or every 4000
hours, whichever comes sooner.

4-94
Maintenance Maintenance Procedure

How to Examine for Looseness of Engine High-Pressure Piping Clamp, Harden-

ing of Rubber
NOTICE
If the engine operation is continued while any bolt is loosened or any rubber is hardened or removed,
the contact portions of the high-pressure piping may be worn and may be broken by vibration. Always
check that the proper high-pressure piping clamps are correctly installed.
Check visually or with a finger to check that there is no hardening of the rubber portion and no loose bolts of the
mounting clamps (2 places) for the high-pressure piping between the supply pump and the common rail.
• If there is any loose bolt or hardened rubber portion, ask your Komatsu distributor for replacement.
• Replacement of the high-pressure piping must be made as an assembly.

4-95
Maintenance Procedure Maintenance

How to Examine for Missing Fuel Spray Prevention Cap, Hardening of Rubber
The fuel spray prevention caps (10 places) on the fuel injection piping and both ends of the high-pressure piping
act to prevent the fuel from coming into contact with high-temperature parts of the engine and causing a fire if
the fuel should leak or spray out.
Check the fuel spray prevention caps visually or with a finger to see if any of them has slipped off, or the rubber
portion is hardened.
If there is any loose bolt or hardened rubber, ask your Komatsu distributor for replacement.

4-96
Maintenance Maintenance Procedure

Every 4500 Hours Maintenance

Maintenance for every 50, 250 and 500 hours should be performed at the same time.

How to Clean DEF Tank

Ask your Komatsu distributor for cleaning of the DEF tank.

How to Clean DEF Tank Mounting Part

Ask your Komatsu distributor for cleaning of the mounting portion of the DEF tank.

How to Replace DEF Tank Filler Port Filter

Ask your Komatsu distributor for replacement of the DEF tank filler port filter.

4-97
Maintenance Procedure Maintenance

Every 8000 Hours Maintenance

Maintenance for every 50, 250, 500, 1000, 2000 and 4000 hours service should be performed at the same time.

How to Replace Fuel Spray Prevention Cap

Ask your Komatsu distributor for replacement of the fuel spray prevention caps.

4-98
Maintenance Maintenance Procedure

Every 9000 Hours Maintenance

Maintenance for every 50, 250, 500, 1000 and 4500 hours service should be performed at the same time.

How to Replace DEF Hose

Ask your Komatsu distributor for replacement of the DEF hose.

4-99
Specifications

5-1
Specifications Specifications

Specifications
Specifications: D51EX-24
With power angle power tilt dozer, ROPS cab
Item Unit D51EX-24
13620 {30032}
Machine weight kg {lb}
[13680 {30164}]
Komatsu SAA4D107E-3 diesel
Engine model -
engine
SAE J1995 (gross) kW {HP} / 99.2 {133} / 2200 {2200}
Rated horsepower
ISO 9249 / SAE J1349 (net) min-1 {rpm} 97.6 {131} / 2200 {2200}
A Overall length mm {ft in} 4800 {15' 9"}
B Overall height (including KOMTRAX antenna) mm {ft in} 3015 { 9'11"}
C Overall width mm {ft in} 3045 {10' 0"}
Travel speed Forward (1st/2nd/3rd) km/h {MPH} 3.4/5.6/9.0 {2.1/3.5/5.6}
(Quick shift mode) Reverse (1st/2nd/3rd) km/h {MPH} 4.1/6.5/9.0 {2.5/4.0/5.6}
Travel speed Forward km/h {MPH} 0.8 to 9.0 {0.5 to 5.6}
(Variable shift mode) Reverse km/h {MPH} 0.8 to 9.0 {0.5 to 5.6}

[ ]: When the wide blade is installed.

5-2
Specifications Specifications

Specifications: D51PX-24
With power angle power tilt dozer, ROPS cab
Item Unit D51PX-24
14040 {30958}
Machine weight kg {lb}
[14100 {31091}]
Komatsu SAA4D107E-3 diesel
Engine model -
engine
SAE J1995 (gross) kW {HP} / 99.2 {133} / 2200 {2200}
Rated horsepower
ISO 9249 / SAE J1349 (net) min-1 {rpm} 97.6 {131} / 2200 {2200}
4800 {15' 9"}
A Overall length mm {ft in}
[4850 {15'11"}
B Overall height (including KOMTRAX antenna) mm {ft in} 3015 { 9'11"}
C Overall width mm {ft in} 3350 {11' 0"}
Travel speed Forward (1st/2nd/3rd) km/h {MPH} 3.4/5.6/9.0 {2.1/3.5/5.6}
(Quick shift mode) Reverse (1st/2nd/3rd) km/h {MPH} 4.1/6.5/9.0 {2.5/4.0/5.6}
Travel speed Forward km/h {MPH} 0.8 to 9.0 {0.5 to 5.6}
(Variable shift mode) Reverse km/h {MPH} 0.8 to 9.0 {0.5 to 5.6}

[ ]: When the high capacity blade is installed.

5-3
Attachments and Options

Please read and make sure that you understand the SAFETY section before
reading this section.

6-1
General Precautions Attachments and Options

General Precautions
Precautions for Safety
If attachments or options other than those authorized by Komatsu are installed, this will not only affect the life of
the machine, but will also cause problems with safety.
When installing attachments not listed in this Operation and Maintenance Manual, contact your Komatsu distrib-
utor first. If you do not contact Komatsu, we cannot accept any responsibility for any accidents or failures.

k WARNING
General precautions
• Read the instruction manual for the attachment carefully, and you must understand the operation
method completely before using the machine..
If you lose the instruction manual, be sure to order another copy from your Komatsu distributor.
• To prevent serious personal injury or death caused by misoperation, you must not place your foot
on the pedal except when operating the pedal.
Precautions for removal and installation
When removing or installing an attachment, observe the following items and work safely.
• Select a firm, level surface when installing or removing an attachment.
• When working in cooperation with one or more other workers, decide signs and observe them when
performing the operation.
• Use a crane when carrying heavy objects (more than 25kg {55.125lb}).
• When removing a heavy part, always place a support in position before removing it.
When lifting a load with a crane, be particularly careful of the center of gravity.
• It is dangerous to perform works when the load has been raised by a crane. Always lower the load
onto a stand and check that it is safe.
• When leaving an attachment removed or installing it, place it in a stable position to prevent it from
falling over.
• Never go under a load raised by a crane.
Always stand in a place which is safe even if the load should fall.

NOTICE
Qualifications are required to operate a crane. Never allow the crane to be operated by an unqualified
person.
For details of removal and installation operations, contact your Komatsu distributor.

6-2
Attachments and Options Handle Hydraulic Ripper

Handle Hydraulic Ripper

This ripper is applicable for D51EX.

General View

(1) Ripper cylinder (4) Shank

(2) Link (5) Point
(3) Beam (6) Support

6-3
Handle Hydraulic Ripper Attachments and Options

Explanation of Components
Ripper Control Lever
k WARNING
When you do the inspection or maintenance of the machine, or when you park the machine, lower the
ripper to the ground and set the work equipment lock lever to the LOCK position.

The ripper control lever is used for operation of the ripper.

(A) RAISE: Ripper goes up.
(B) HOLD: Ripper is stopped and held in this position.
(C) LOWER: Ripper goes down.

REMARK
Hold the operating portion on the top to operate the work
equipment lock lever, set the lever in theLOCK position (L), and
the operation of the ripper is locked.

6-4
Attachments and Options Handle Hydraulic Ripper

Radiator Grille
Open and close the radiator grille as needed in check and maintenance.

How to Open and Close Radiator Grille

k WARNING
• Stop the engine before opening or closing the radiator grille, and open or close it while the fan is
stopped.
If you touch the rotating fan, it will cause serious personal injury or death.
• Be careful not to get your finger caught in the gap between the radiator grille and tank while open-
ing and closing the radiator grille.
• Check that the lock is securely set when opening the radiator grille. Check the lock and link part as
well for abnormality.
• Be careful not to hit your head, etc. against radiator grille when opening it.
• Check the hoses and piping which move together with the radiator grille for cracks and damage.

Procedure to Open Radiator Grille

1. Remove the bolts (1) (4 pieces) on the lower part of the ra-
diator grille, and remove the cover (2).

2. Pull the radiator grille backward and raise it upward.

3. Open the radiator grille to the fully opened position, check
that it is locked, and then release your hand.

6-5
Handle Hydraulic Ripper Attachments and Options

Procedure to Close Radiator Grille

NOTICE
Radiator grille cannot be closed unless it is unlocked. If you try to close the radiator grille without un-
locking, it may break.
1. Lift up the radiator grille, and push the lock releasing bar
(3) to the direction of arrow.
The lock is released.

2. Install the cover (2), and tighten the bolts (1) (4 pieces) on
the lower part of the radiator grille.

6-6
Attachments and Options Handle Hydraulic Ripper

Machine Operations and Controls

Checks and Adjustment Before You Start Engine
How to Do Walk-Around Check
Check for wear of the point at the tip of the shank, check the mounting condition, and check for damage to the
rivets.
If any problem is found, replace or repair it.

Precautions for Operation

• Lower the ripper gradually when starting to move the machine off. Drive the machine at low speed. When
the optimum digging depth is reached, set the ripper control lever to HOLD position.
Do not dig the shank in deep when starting digging operations.
• During ripping operations, never turn the machine suddenly or travel in reverse. When turning the machine
suddenly or traveling in reverse, raise the shank from the ground surface.
• When performing digging operations with only one shank, always use the center shank. Remove both side
shanks.
• The point end touches the ground at the start of an uphill and at the end of a downhill. If the ground is hard
at this time, the ripper may be damaged. To prevent this, raise the shank to the highest position.

6-7
Handle Hydraulic Ripper Attachments and Options

Adjust Work Equipment

How to Adjust Depth to Dig
There are mounting pin holes on the shank. Select one of them, depending on the digging depth.

Maximum digging
Pin hole position Use depth
(mm {in} )
When there is spe-
(A) cial need to dig 508 {20.0}
deeply
(B) When normal 428 {16.9}

When changing the digging depth, do as follows.

1. Remove the cotter pin (1).
2. Remove the pin (2).
3. Change the shank hole position, and insert the pin (2).
4. Insert the cotter pin (1).

How to Replace Ripper Point

A point is installed to protect the shank. If the point is worn, replace it according to the following procedure.
1. Put a pin puller to the pin indicated by the arrow, and hit it
with a hammer to drive out the pin.
The pin comes off.
2. Replace the point.
3. Insert the pin halfway.
4. Drive in the pin with the hammer.

6-8
Attachments and Options Handle Hydraulic Ripper

Troubles and Procedures

Other Trouble
• Contact your Komatsu distributor for the remedies indicated with (*) in the remedy column.
• In cases of problems or causes which are not listed below, ask your Komatsu distributor for repairs.
Problem Main causes Remedy
Lack of rising and pushing force Inappropriate hydraulic oil Add oil to specified level by
of ripper referring to EVERY 250
Slow moving HOURS MAINTENANCE.
Defective pump Check, repair. (*)
Incorrect adjustment of relief valve Check, adjust. (*)
Defective control valve and safety valve Check, repair. (*)
Defective valve spool Check, repair. (*)
Defective piston ring, packing, or valve Check, repair. (*)
Clogging inside piping Check, repair. (*)
Cylinder lacks holding power. Leakage of oil from piping or hose Tighten, check, replace the
O-ring or hose.
Defective piston ring or packing Replace. (*)
Defective piston valve Check, repair. (*)
Defective valve spool Check, repair. (*)
Defective safety valve, defective suction valve Check, repair. (*)
Oil pressure does not rise. Clogging inside piping Repair. (*)
Incorrect adjustment of relief valve Check, adjust. (*)

6-9
Handle Hydraulic Ripper Attachments and Options

Examine and Maintenance

Every 250 Hours Maintenance
Lubrication
1. Lower the ripper to the ground and stop the engine.
2. By using a grease pump, pump in grease through the grease fitting.
3. After greasing, wipe off any old grease that is pushed out.

(1) Ripper cylinder foot pin (1 place) (3) Link pin (8 places)
(2) Ripper cylinder rod end pin (1 place)

How to Examine Oil Level in Hydraulic Tank, Add Oil

1. Place the machine on a level ground and lower the work equipment to the ground.
If the machine is inclining, make it level.
2. Make the blade perpendicular and lower it to the ground.
3. Make the ripper point touch the ground.
4. Stop the engine.
5. Check oil level in hydraulic tank.
For details, see OPERATION, “METHOD FOR CHECKING OIL LEVEL IN HYDRAULIC TANK, ADDING
OIL”.

6-10
Attachments and Options Handle Hydraulic Ripper

Specifications: D51EX-24
Power angle power tilt dozer (Machine with ripper)

Item Unit D51EX-24

Machine weight
(excluding the weight of opera- kg {lb} 14570 {32127}
tor)
Ripper unit weight kg {lb} 872 {1923}
A Overall length mm {ft in} 5850 {19' 2"}
Number of shanks - 3

6-11
Handle External Power Supply Engine Preheater Attachments and Options

Handle External Power Supply Engine Preheater

In cold weather, there may be a need for heating the coolant and lubricating oil. In such case, perform the fol-
lowing items for warming up, then start up the engine, and operate the machine.
External power supply engine preheater is provided as an option for heating the coolant and lubricating oil,
which keeps the warmth so that the engine can be started up easily even when the machine is parked in cold
district.
The external power supply engine preheater keeps warmth of the following coolant and lubricating oil.
1. Engine oil
2. Engine coolant
External power supply engine preheater is an auxiliary engine starting aid which is used when the engine start-
ing is difficult due to cold weather in which the ambient temperature drops under -20 °C {-4 °F} or even when it
is higher than -20 °C {-4 °F} .
It utilizes the external power supply (single-phase AC current 120 V) to make the engine starting up easier by
heating the engine coolant and oil in the engine oil pan.

6-12
Attachments and Options Handle External Power Supply Engine Preheater

Install External Power Supply System for External Power Supply Engine
Preheater
1. It is necessary to install the following external power supply system when using the external power supply
engine preheater.
For details, see “Install External Power Supply System”.
2. The cables for introducing the above mentioned electricity from the external power supply system to the ex-
ternal power supply input (receptacle) on the machine need to be fabricated locally.
For fabricating procedure, see “Make External Power Supply Cable”.
3. The external power supply inputting cable is a electric cable which introduces the electricity from the local
AC power supply to the external power supply input (receptacle) on the machine.
Connect it according to the procedures shown in the following figure, and actuate the external power supply
engine preheater.

No. Name Necessary condition

• Supplying capacity is more than 8.5 kVA.
• Main switch is installed.
1 Power supply system
• Ground-fault circuit interrupter (capable of preventing electrical leak-
age and overload) (Note. 1)

Supply source (electrical • Single-phased AC current.

2
feeder line) • Voltage is 120 V.
• The ground cable must be grounded.
3 Ground cable (Note.2)
• Bury the ground cable in the ground for grounding.
• Prepare cable which meet the following conditions.
1. 3-core cable
External power supply in- 2.
4
putting cable
Nominal cross-sectional area of 1-core is 5 mm2 { 0.0078 in2}.
3. Cabtyre cable type
4. Length is less than 30 m { 98 ft 5 in } (Note. 3).

Note. 1: Ground-fault circuit interrupter is installed so that persons on the machine are protected from the
electric shock in case the supplied electric current is leaked to the machine.
Note. 2: Ground cable is buried in the ground for the same reason as (Note. 1).

6-13
Handle External Power Supply Engine Preheater Attachments and Options

Note. 3: This is to prevent the voltage drop.

6-14
Attachments and Options Handle External Power Supply Engine Preheater

Make External Power Supply Cable

External power supply cable can be fabricated according to the local need, but here we provide some guidance
it should be in conformity to.
Fabricate two cables in accordance with the following procedure.
1. Locally buy the 3-core chloroprene sheathed cabtyre cable.
• Appropriate cross-sectional area of the single core is 5 mm2 { 0.0078 in2}.
• Withstanding voltage should be resistant against 3000 V or one minute.
• Length should be less than 30 m { 98 ft 5 in } in order to prevent the voltage drop.
• Cross section as an example
(1) Chloroprene sheathe
(2) Conductor
(3) Paper tape
(4) Insulator

6-15
Handle External Power Supply Engine Preheater Attachments and Options

2. Connect the input plug (5) (17A-06-23320) for the machine body side, terminal (8) (08860-00404), and wa-
terproof cover (13) (17A-06-23330) to the tip of the cable (14).
1) Put the cable (14) through the waterproof cover (13).
2) Connect the 3-core wires (10) of the cable (14) and the terminal (8) by soldering.
3) Perform insulating on the connecting portion of the core wires (10) and terminal (8) by using rubber
tube or tape (11).
4) Plug (5) has contacts (6) (3 pieces), and each contact has a symbol. Connect the terminal (8) to the
contacts (6) with corresponding symbols.
Connect the terminal (8) to the contacts (6) by screwing.
Tightening torque: 1.2 Nm {0.12 kgfm, 0.87 lbft}

(5) Plug body (17A-06-23320) (10) Core wire

(6) Contact (17A-06-23320) (11) Insulating tube or tape
(7) Screw (17A-06-23320) (12) Insulator
(8) Terminal (08860-00404) (13) Water proof cover (17A-06-23330)
(9) Solder (14) Cable
Contact Core wire to connect
A Power source circuit wire
B Power source circuit wire
C Ground circuit wire

k CAUTION
• Be sure to perform soldering the connecting portion of the terminal (8) and the core wires (10).
• Fit the soldering parts with a rubber tube or wrap with the tape (11) to insulate the soldering
parts and prevent short circuit caused by contact between conductors.
• Use 17A-06-23320 for the plug (5). If any other plug is used, it will be impossible to connect to
the external power supply input (receptacle).

6-16
Attachments and Options Handle External Power Supply Engine Preheater

3. Modify the other end of the cable so that it can be connected to the external power supply system.
Fabrication of the external power supply cable is completed when the modification for the connection is fin-
ished.

(D) To power supply to the input socket (recep- (F) Triplex core cabtire cable (The length
tacle) on the machine should be less than 30 m { 98 ft 5 in } )
(E) To power supply

Install External Power Supply System

k CAUTION
Install the external power supply system in accordance with all related laws and regulations in that
country. Also, install it by an authorized contractor.

To use the external power supply engine preheater, an external power supply system such as a system which is
shown in the figure of item 3., in “INSTALLATION PROCEDURES FOR EXTERNAL POWER SUPPLY SYSTEM
FOR EXTERNAL POWER SUPPLY ENGINE PREHEATER” is necessary.
The external power supply system is a facility which supplies the AC voltage sent from a generator or substation
electricity to the preheater. The structure of the power supply facility must allow the external power supply input-
ting cable to be easily connected to it.
The shape, size, and method of setting up the facility can be decided locally, but the specifications should be as
follows. The machine side has no switch nor safety device.
• Specification of the power supply system
• (1) Output electricity type: Single-phased AC current
• Output voltage: 120 V
• Power supply volume: 8.5 kVA
• Main switch: Equipped
• Electrical leakage breaker: Equipped
• Ground circuit: Equipment

6-17
Handle External Power Supply Engine Preheater Attachments and Options

• System diagram of external power supply engine preheater (as a reference for the work)

(1) Engine oil pan heater (150 W/120 V) (5) Plug

(2) Coolant heater (750 W/120 V) (6) External power source input cable
(3) Grounding to machine body (7) Power source cable
(4) Power supply to the input socket on the machine (8) Ground cable

6-18
Attachments and Options Handle External Power Supply Engine Preheater

• General wiring diagram of external power supply engine preheater (as a reference for the work)

(1) Engine oil pan heater (150 W/120 V) (4) Water proof fuse
(2) Coolant heater (750 W/120 V) (5) Grounding to machine body
(3) Fusible link (6) Connect to the external power supply (120 V)
Check that the waterproof fuse (4) is disconnected by tester.
(Part number for replacing fuse: 17A-06-23230)

Examine Operation After You Assemble

After the external power supply facility has been installed, check it according to the following procedure
1. Check for leakage of oil and water.
2. Check for interference of wiring harnesses.
3. Connect to the external power supply facility, and check that the voltage at each heater connector is ener-
gized in 120 V by using a tester.

6-19
Handle External Power Supply Engine Preheater Attachments and Options

How to Start Engine in Cold Weather

k WARNING
• Be sure to lower the work equipment to the ground.
• Be sure to remove the oil and fuel if they are attached to the preheater body and around it.
• Be sure to remove the dry leaves and combustibles if they are accumulated in the engine room.
• Check that the engine lubricating oil and engine coolant are filled to the specified level. (More than
half of the specified level)
• Check that the engine lubricating oil and engine coolant are filled to the specified level.
• Check before distributing the power that there is no damage on the wire coating. If any, replace the
wire or repair it.
• Never connect the cable before turning the power supply switch to ON position. It is dangerous.
• Be sure that the ground cable is securely grounded, and turn the power supply switch to ON posi-
tion.

Use the external power supply engine preheater when the starting up of the engine is difficult due to cold weath-
er in which the ambient temperature drops under -20 °C {-4 °F} or even when it is higher than -20 °C {-4 °F} .
1. Park the machine when finishing operation so that the external power supply inputting cable can reach to
the external power supply system for the next time you use the preheater for starting up the engine.
NOTICE
• Place the machine on a level ground.
• Treat the track so that it will not be frozen on the ground.
REMARK
Covering the machine with a cover makes the starting up of engine even easier.
2. Warm-up the coolant and oil in engine oil pan by distributing the power to the preheater a couple of hours
before starting up the engine according to the following procedure.
1) Connect the power supply system and the receptacle on the external power supply input (receptacle)
of the machine with the cable.
The external power supply input (receptacle) of the
machine is installed inside the cover on the front of the
machine.

6-20
Attachments and Options Handle External Power Supply Engine Preheater

(A) Plug for heater

(B) Power supply (C) External power source input cable

2) Start distributing the power with the power supply switch of the power supply system (main switch) or
the switch for distributing the power if equipped.
• Power distributing time varies with the ambient temperature and type of oil.
• You may start distributing the power soon after stopping the engine on the previous day if the am-
bient temperature is lower than -15 °C {5 °F} , so that the engine is kept warm.
• If the climate of your area is unique, find the usage standard which is well-suited for the area and
standardize it for better efficiency.
NOTICE
• Perform the warm-up operation by referring to “How to Start Engine in Cold Weather” if the am-
bient temperature is lower than 0 °C {32 °F} .
• Stop distributing the power if the ambient temperature is higher than 0 °C {32 °F} . Oil will be de-
teriorated if the oil temperature is too high.
• Keep the engine warm using this preheater when the engine is stopped for more than 2 hours
and the ambient temperature is lower than -20 °C {-4 °F} .
3. Turn off the power supply switch when the preheating is completed. Remove the cable, and screw the pro-
tection cap into the external power supply input (receptacle) of the machine.
4. Start up the engine.
NOTICE
Do not start up the engine during distribution of the power. Be sure to turn off the power supply
switch, and start up the engine.
Starting up the engine during the distribution of the power will cause the failure in coolant heater.

6-21
Replacement Parts

7-1
Periodic Replacement of Defined Life Parts Replacement Parts

Periodic Replacement of Defined Life Parts

For using the machine safely for an extended period of time, Komatsu highly recommends the periodic replace-
ment of the defined life and fire prevention-related parts listed in the table of the defined life parts.
Material quality of these parts can change as time passes and they are likely to wear out or deteriorate. Howev-
er, it is difficult to determine the extent of wear or deterioration at the time of periodic maintenance. Hence, it is
required to replace them with new ones regardless of their condition after a certain period of usage. This is im-
portant to ensure that these parts maintain their full performance at all times.
Furthermore, should anything abnormal be found on any of these parts, replace it with a new one even if the
periodic replacement time for the part has not yet arrived.
If any of the hose clamps show deterioration like deformation or cracking, replace the clamps at the same time
as the hoses.
Also perform the following checks with hydraulic hoses which need not to be replaced periodically. Tighten all
loose hoses and replace defective hoses, as required.
When replacing hoses, always replace O-rings, gaskets, and other such parts at the same time.
Have your Komatsu distributor replace the defined life parts.

Defined Life Parts List

No. Periodical replacement parts Replacement interval
1 Fuel system Fuel hose
2 Engine lubrication system Engine oil filter hose
3 Steering system High pressure circuit hose
4 Brake system Brake oil pressure hose
5 Torque converter, trans-
mission system (including Transmission circuit hose (including HST)
HST)
6 Work equipment hydraulic Work equipment pump delivery hose Every 2 years or 4000 hours,
system whichever comes sooner
Work equipment pump LS hose
Hose for hydraulic drive fan
External work equipment hose
• Blade lift hose
• Blade tilt hose
• Blade angle hose
• Ripper lift hose
7 Others PPC accumulator
Every 3 years from start of us-
age or 5 years after manufactur-
Seat belt
ing of seat belt, whichever
comes sooner.

7-2
Replacement Parts Consumable Parts

Consumable Parts
Replace consumable parts such as the filter element or air cleaner element at the time of periodic maintenance
or before they reach the wear limit. The consumable parts should be replaced correctly in order to ensure more
economic use of the machine. When replacing parts, Komatsu recommends using Komatsu genuine parts.
As a result of our continuous efforts to improve product quality, the part number may change. Inform your Ko-
matsu distributor of the machine serial number and check the latest part number when ordering parts.

Consumable Parts List

The parts in parentheses are to be replaced at the same time.
Weight Replacement inter-
Item Part No. Part name Q'ty
(kg {lb}) val

Engine oil filter 6736-51-5142 Cartridge - 1

Fuel prefilter 600-319-3610 Cartridge - 1
Fresh air filter 12Y-979-1174 Filter - 1 Every 500 hours
Air condi-
tioner Recirculation
12Y-979-6180 Filter - 1
air filter
Cartridge
Fuel main filter 600-319-3750 - 1
(with cap)
Hydraulic tank breather 421-60-35170 Element - 1 Every 1000 hours
DEF tank breather 421-60-35170 Element - 1
Fuel tank breather 421-60-35170 Element - 1
Hydraulic oil filter 11Y-60-51310 Cartridge - 1
KCCV filter 600-331-2900 Element - 1
Every 2000 hours
HST oil filter 12Y-60-38710 Cartridge - 1
DEF filter 6540-71-2320 Filter kit - 1
Radiator cap 12Y-03-34510 Cap - 1 Every 4000 hours
Air cleaner 600-185-3100 Element assembly - 1 -
12Y-72-11220 Cutting edge (center) 20.8 {45.9} 1
12Y-72-11230 Cutting edge (both ends) 24.9 {54.9} 2
High capacity
blade / Wide 12Y-72-11210 End bit 10.2 {22.5} 2
blade
(02090-11270) (Bolt) - (25)
Blade (02290-11219) (Nut) - (25) -
12Y-72-11220 Cutting edge 20.8 {45.9} 3
12Y-72-11210 End bit 10.2 {22.5} 2
Narrow blade
(02090-11270) (Bolt) - (23)
(02290-11219) (Nut) - (23)

NOTICE
When handling parts that weigh more than 25 kg {55.1 lb}, remember that they are heavy objects, and
take the necessary care.

7-3
Recommended Fuel, Coolant, and Lubricant Replacement Parts

Recommended Fuel, Coolant, and Lubricant

• Komatsu genuine oils are conditioned to maintain the reliability and durability of Komatsu construction
equipment and components.
• Commercially available lubricant additives may be good or bad for the machine. Komatsu does not recom-
mend any commercially available lubricant additive.
• Komatsu recommends using Komatsu genuine engine oil. If using engine oil other than Komatsu genuine
oil, it may reduce lubricant function. This causes shorter engine life, lowered engine performance and in-
creased fuel consumption.
• Use the fuel, oil, and lubricants to match the ambient temperature as recommended in the chart below.
• If the machine is operated at a temperature of –20 °C or lower {–4 °F or lower} , consult your Komatsu dis-
tributor.
Fuel
NOTICE
Always use ultra-low-sulfur diesel fuel.
The ASTM diesel fuel recommended by Komatsu may con-
tain 5 % or less of biofuel. The EN diesel fuel may contain
7 % or less of it. Use the fuel which is filled into the storage
tank or the fuel tank of the machine as soon as possible.
When the diesel fuel is changed to the one mixed with the
bio-fuel, replace the fuel prefilter cartridge and the fuel
main filter cartridge with new ones.
Do not use any additive agent which includes metallic con-
stituent.
The metallic constituents in the additive agent may exces-
sively wear or damage the aftertreatment devices.
Diesel Exhaust Fluid (DEF)
DEF is a colorless transparent and aqueous urea solution made with 32.5 % urea (AUS32) and 67.5 % deion-
ized water.
Use commercial DEF, that is API (American Petroleum Institute) certified and fulfills the quality requirements in
accordance with ISO 22241-1. Certified DEF has the API DIESEL EXHAUST FLUID Certification Mark shown
as follows. Look for the API DEF Certification Mark when you purchase DEF.
API Diesel Exhaust Fluid Certification Mark is the trademark of
API (American Petroleum Institute).

Lubrication Chart
• The lubrication chart uses symbols to show the lubrication points and types of lubricant by each lubrication
interval.
• Even if the same symbol is used in the lubrication chart, the recommended genuine oil may differ according
to the lubrication points and the ambient temperature.

7-4
Replacement Parts Recommended Fuel, Coolant, and Lubricant

D51PX D51EX
D51PXI D51EXI
.

.
.

Z
Z
.

.
P

.
.

P
.

10h
.

50h
.
250h
500h
.

1000h
2000h
12Y-98-35130

The symbols used in the lubrication chart are explained in the following table.

7-5
Recommended Fuel, Coolant, and Lubricant Replacement Parts

Symbol Meaning of the symbol Symbol Meaning of the symbol

Read Operation and Maintenance Manual Supply grease

Change engine oil Check oil level in engine oil pan

Change hydraulic oil Check hydraulic oil level

Change oil in final drive case Replace final drive case

Replace hydraulic oil filter and clean hy-

Replace engine oil filter
draulic tank strainer

Replace breather element in hydraulic tank Replace fuel main filter

Replace KCCV filter Replace breather element in fuel tank

Check oil level in pivot shaft and add oil Replace fuel prefilter

Replace HST oil filter Replace DEF tank breather element

Replace DEF filter

7-6
Replacement Parts Recommended Fuel, Coolant, and Lubricant

How to Use Fuel, Coolant and Lubricants by Ambient Temperature

Ambient temperature
Recommended
Reservoir Fluid type °C °F
Komatsu Fluids
Min Max Min Max
Engine oil for KDPF used in EOS5W30-LA
-40 35 -40 95
cold terrain (KES)
(Oil Change interval 250 hours) EOS5W40-LA
-40 40 -40 104
(Note.1) (KES)
Engine oil pan
EO10W30-LA
-20 40 -4 104
Engine oil for KDPF (KES)
(Oil Change interval 500 hours) EO15W40-LA
-15 50 5 122
(KES)
TO30 (KES) -30 50 -22 122
Final drive case (each) Power train oil
TOS0W30 (KES) -40 40 -40 104
Power train oil TOS0W30 (KES) -40 40 -40 104
EO10W30-DH
-20 50 -4 122
Hydraulic System (KES)
Engine oil
EO15W40-DH
0 50 32 122
(KES)
Hyper grease (Note.2) G2-TE (KES) -20 50 -4 122
Grease fitting Lithium grease GLT2-LI (KES) -40 30 -40 86
Lithium EP grease G2-LI (KES) -20 50 -4 122
Non-Amine Engine Coolant
Cooling system AF-NAC (KES) -40 50 -22 122
AF-NAC (Note.3)
ASTM D975 No.
-30 20 -22 68
1–D S15
Fuel tank Diesel fuel
ASTM D975 No.
0 50 32 122
2–D S15
DEF tank DEF (Note.4) DEF -40 50 -22 122

KES: Komatsu Engineering Standard

ASTM: American Society of Testing and Material
Specified capacity Refill capacity
Reservoir
Liter US gal Liter US gal
Engine oil pan 17.5 4.62 15.5 4.1
Idler (each) 0.21 0.056 0.21 0.056
Final drive case (each) 6.0 1.58 5.5 1.45
Hydraulic System 125 33 63 16.6
Cooling system 45 11.9 25 6.61
Fuel tank 273 72.1 — —
DEF tank 24.8 6.6 — —

7-7
Recommended Fuel, Coolant, and Lubricant Replacement Parts

REMARK
Specified capacity means the total amount of oil including the oil in the tank and the piping. Refill capacity
means the amount of oil needed to refill the system during inspection and maintenance.
Note 1: KDPF engine oil for cold district is deteriorated easily than that for normal area (replace every 500
hours), so replace oil and filter cartridge every 250 hours. For changing the maintenance time of machine moni-
tor, ask your Komatsu distributor to perform the work.
Note 2: Hyper grease (G2-TE) has a high performance. When it is necessary to improve the lubricating ability of
the grease in order to prevent squeaking of pins and bushings, the use of G2-TE is recommended.
Note 3: Non-Amine Engine Coolant (AF-NAC)
1. The coolant has the important function of preventing corrosion as well as preventing freezing.
Even in the areas where freezing is not an issue, the use of coolant is essential.
Komatsu recommends the use of Non-Amine Engine Coolant (AF-NAC). If you use another coolant, it may
cause serious problems in the cooling system, including the engine.
Komatsu machines are supplied with Non-Amine Engine Coolant (AF-NAC). Non-Amine Engine Coolant
(AF-NAC) has excellent anti-corrosion, antifreeze and cooling properties and can be used continuously for
2 years or 4000 hours.
Non-Amine Engine Coolant (AF-NAC) is strongly recommended wherever available.
2. For the density of Non-Amine Engine Coolant (AF-NAC), see “Coolant density table”.
Non-Amine Engine Coolant (AF-NAC) is supplied already diluted. In this case, fill up the tank with pre-dilu-
ted fluid. (Never dilute the Non-Amine Engine Coolant with ordinary water.)

Coolant Density Table

-10 or
°C -15 -20 -25 -30 -35 -40 -45 -50
Min. atmospheric tempera- more
ture 14 or
°F 5 -4 -13 -22 -31 -40 -49 -58
more
Density(%) 30 36 41 46 50 54 58 61 64
Note 4: The DEF freezes at -11 °C {12.2 °F} . If thawing is necessary, the DEF system is automatically heated to
thaw DEF after the engine is started.

Recommended Brands and Qualities Other Than Komatsu Genuine Oils

When using commercially available oils other than Komatsu genuine oil, consult your Komatsu distributor.

7-8
INDEX

INDEX
Symbols Be careful of Asbestos Dust..................................2-18
Blade Control Lever............................................ 3-101
1st Travel Speed Setting.......................................3-47 Blade Mode...........................................................3-47
2nd Travel Speed Setting......................................3-48 Blade Mode Display.............................................. 3-30
3rd Travel Speed Setting...................................... 3-49 Bleed Air from Hydraulic System............................ 4-4
Blower Changeover Switch.................................3-234
A Brake on Downhill............................................... 3-215
Brake System Caution Lamp................................ 3-20
Action Level Display..............................................3-13 Burn Prevention...................................................... 4-3
Adjust Blade Edge Angle.................................... 3-220 Buzzer Cancel Switch........................................... 3-42
Adjust Camera Image Brightness......................... 3-82
Adjust Frequency................................................ 3-239
Adjust Lumbar Support...................3-174,3-177,3-180
C
Adjust Operator's Seat........................................ 3-172 Calendar Setting................................................... 3-86
Adjust Seat Fore-and-Aft Direction.3-172,3-175,3-178 Camera Image Selector Switch............................ 3-52
Adjust Shim of Center Ball.................................... 4-52 Camera Screen Adjustment..................................3-81
Adjust Weight and Height of Seat.............3-173,3-176 Cap and Cover with Lock....................................3-109
Adjust Work Equipment.......................................... 6-8 Caution Lamp List................................................. 3-14
Adjustment..................................................3-172,4-29 Change 12H/24H Display Mode........................... 3-88
After Cold Weather Season................................ 3-250 Change Display Setting........................................ 3-66
Aftertreatment Device Regeneration Display........3-29 Change Display/Non-Display of ECO Gauge and
Aftertreatment Device System Caution Lamp.......3-21 Drawbar Pull Gauge...................................... 3-69
Aftertreatment Devices Regeneration...................3-77 Change Display/Non-Display of ECO Guidance...3-71
Air Cleaner Clogging Caution Lamp..................... 3-25 Change Display/Non-Display of Guidance When Key
Air Conditioner Mode Selector Switch................ 3-233 is Off...............................................................3-72
Air Conditioner Switch.........................................3-100 Change Gear Shift Mode.................................... 3-203
Air Suspension Seat (High-Back Seat)............... 3-178 Change Oil in Final Drive Case.............................4-62
Air Suspension Seat (Low-Back Seat)................3-172 Change Oil in Hydraulic Tank, Replace Hydraulic Oil
Allowable Water Depth........................................3-215 Filter Cartridge, Replace HST Oil Filter Cartridge,
Always Use Clean Washer Fluid.............................4-2 and Clean Hydraulic Tank Strainer................ 4-79
Antenna...............................................................3-241 Charge Level Caution Lamp................................. 3-25
Ashtray................................................................3-109 Check............................................................4-17,4-29
Assign Leader When You Work with Others......... 2-27 Checks After Inspection and Maintenance............. 4-5
Auto Idle Stop Timer Setting................................. 3-76 Checks After You Stop Engine............................3-227
AUX.....................................................................3-238 Checks and Adjustment Before You Start Engine........
Avoid Mixing Oil...................................................... 4-4 ...................................................... 2-19,3-150,6-7
Checks Before Operation......................................2-21
B Checks Before You Stop Engine.........................3-227
Cigarette Lighter................................................... 3-96
Band/AUX Selector Button..................................3-236 Clean and Examine Radiator Fins and Oil Cooler Fins
Basic Operation of Machine Monitor.......................3-6 .......................................................................4-37
Basic Operation of Machine Monitor When Starting Clean Fin by Reverse Rotation of Hydraulic Drive Fan
Switch is ON While Operator ID Input is Set... 3-8 .......................................................................4-37
Basic Operation of Machine Monitor When Trouble Clean Fuel Tank Breather..................................... 4-41
Occurs While You Operate Machine.............. 3-11 Clean Hydraulic Tank Breather............................. 4-41
Basic Operation of Machine Monitor When You Start Clean Lubricants..................................................... 4-2
Engine in Abnormal Situation.......................... 3-9 Clean Radiator Fin................................................ 4-40
Basic Operation of Machine Monitor When You Start Clock Adjustment.................................................. 3-85
Engine in Normal Situation.............................. 3-6 Cold Weather Operation..................................... 3-248
Basic Operation of Machine Monitor When You Start Cold Weather Operation Information.................. 3-248
Engine While Engine Shutdown Secondary Consumable Parts.................................................. 7-3
Switch is on......................................................3-7 Consumable Parts List............................................7-3
Basic Operation of Machine Monitor When You Stop Control Levers and Pedals........................... 3-3,3-101
Engine in Normal Situation.............................. 3-7 Coolant................................................................3-248
Battery.................................................................3-249 Coolant and Water for Dilution................................ 4-7
Battery Disconnect Switch.................................. 3-118 Cup Holder..........................................................3-109

8-1
 INDEX

Current Abnormality Display Switch......................3-17 Examine and Maintenance................................... 6-10

Customize Switch................................................. 3-44 Examine and Replace Alternator Drive Belt Tension
and Replacing Alternator Belt........................ 4-76
D Examine Before You Start Operation.................... 4-54
Examine Door Lock Striker................................... 4-42
Daylight Saving Time (Summer Time) Setting...... 3-88 Examine Drained Oil and Used Filter......................4-2
Decelerator/Brake Pedal.....................................3-103 Examine ECO Guidance Record.......................... 3-63
DEF...............................................................3-248,4-8 Examine for Looseness of ROPS Mount Bolt....... 4-76
DEF Filter............................................................3-148 Examine Jobsite Conditions..................................2-16
DEF Level Caution Lamp......................................3-22 Examine Oil Level in Idler..................................... 4-33
DEF Level Gauge................................................. 3-39 Examine Operation After You Assemble...............6-19
DEF System Caution Lamp.................................. 3-22 Examine Seatbelt................................................3-182
DEF System High Temperature Stop Caution Lamp.... Examine Service Meter Reading............................ 4-2
.......................................................................3-23 Examine Water Pump........................................... 4-93
Defined Life Parts List.....................................4-93,7-2 Explanation of Air Conditioner Components....... 3-233
Directions of Machine............................................. 1-5 Explanation of Components..............................3-5,6-4
Display................................................................ 3-237 Explanation of Radio Equipment.........................3-236
Display Selector Button.......................................3-237
Do KOWA (Komatsu Oil Wear Analysis).................4-9
Do Not Change CAB Glass in Any Way that Will
F
Block the View............................................. 3-216 Fan Control System Caution Lamp.......................3-24
Do Not Disassemble Recoil Spring.......................2-35 Fan Reverse Rotation Pilot Lamp......................... 3-28
Do Not Drop Things Inside Machine....................... 4-2 Features of Modes.............................................. 3-212
Do Not Get Caught............................................... 2-14 Filter...................................................................... 4-10
Do Not Go Close to High-Voltage Cables............. 2-17 Fire Extinguisher................................................. 3-116
Do Not Jump On or Off Machine...........................2-13 First Aid Kit..........................................................3-117
Do Not Open Door While You Operate Machine.3-216 Float Mode Pilot Lamp.......................................... 3-29
Door Open Lock..................................................3-108 Foot Heater Switch............................................. 3-100
Dozing Work....................................................... 3-217 For Safety Operation...............................................2-9
Dust Indicator......................................................3-121 Fuel......................................................................... 4-7
Dusty Jobsites.........................................................4-4 Fuel and Lubricants............................................ 3-248
Fuel Consumption Gauge..................................... 3-38
E Fuel Control Dial................................................... 3-96
Fuel Gauge........................................................... 3-35
ECO Gauge/Drawbar Pull Gauge......................... 3-38 Fuel Level Caution Lamp...................................... 3-18
ECO Guidance......................................................3-62 Function of Accumulator....................................... 4-83
Emergency Exit from Operator Cab......................2-14 Function Switches.................................................3-44
Engine Coolant Temperature Caution Lamp.........3-18 Function Switches and Guidance Icons................3-40
Engine Coolant Temperature Gauge.................... 3-34 Fuse.................................................................... 3-112
Engine Oil Pressure Caution Lamp.......................3-24 Fusible Link......................................................... 3-115
Engine Overrun Caution Lamp............................. 3-24
Engine Shutdown Secondary Switch.................... 3-99
Engine Stop Pilot Lamp........................................ 3-28
G
Engine System Caution Lamp.............................. 3-23 Gear Shift Mode....................................................3-45
Engine Technology to Conform Exhaust Gas Emis- Gear Shift Mode Selector Switch.......................... 3-43
sion.................................................................. 1-6 General Character and Precautions for Handling. 2-38
Engine Warm-up Operation................................ 3-194 General Precautions............................................... 6-2
Engine Warm-up Operation in Cold Season....... 3-195 General Precautions Common to Operation and
Every 1000 Hours Maintenance............................4-70 Maintenance.................................................... 2-9
Every 2000 Hours Maintenance............................4-79 General View.................................................... 3-2,6-3
Every 250 Hours Maintenance..................... 4-56,6-10 GPS Synchronization Setting................................3-85
Every 4000 Hours Maintenance............................4-93 Grease.................................................................... 4-8
Every 4500 Hours Maintenance............................4-97 Grease Pump Holder.......................................... 3-116
Every 50 Hours Maintenance................................4-55 Guidance Display..................................................3-31
Every 500 Hours Maintenance..............................4-62
Every 8000 Hours Maintenance............................4-98 H
Every 9000 Hours Maintenance............................4-99
Examine Accumulator Function............................ 4-84 Handle Accumulator..............................................2-36
Handle Air Conditioner........................................3-233

8-2
INDEX

Handle Battery...................................................... 2-31 How to Examine and Do Maintenance Air Conditioner

Handle Electrical Components..............................4-11 .......................................................................4-46
Handle External Power Supply Engine Preheater 6-12 How to Examine and Repair............................... 3-223
Handle High-Pressure Hoses and Piping............. 2-33 How to Examine Battery Electrolyte Level............ 4-58
Handle Hydraulic Components............................. 4-11 How to Examine Before You Start Operation......3-152
Handle Hydraulic Ripper......................................... 6-3 How to Examine Brake Performance Curve......... 4-61
Handle ID Key.....................................................3-122 How to Examine Coolant Level, Add Coolant..... 3-156
Handle Oil, Fuel, Coolant, and Do Oil Clinic........... 4-6 How to Examine Decelerator/Brake Pedal Stroke.......
Handle Radio...................................................... 3-236 .....................................................................3-171
Handle Urea SCR System.................................. 3-130 How to Examine DEF Level and Add DEF......... 3-161
Head Lamp Switch................................................3-98 How to Examine Door Latch................................. 4-42
High Register Range (Treble) Setting................. 3-240 How to Examine During Off Season........... 3-235,4-49
Horn Switch...........................................................3-98 How to Examine Dust Indicator...........................3-159
How to Add DEF from BIB Container..................3-164 How to Examine Electric Wiring..........................3-159
How to Adjust Air Conditioner Compressor Belt Ten- How to Examine Electric Wiring Around Starting Mo-
sion................................................................ 4-48 tor and Alternator........................................... 4-69
How to Adjust Armrest........................................ 3-181 How to Examine Electrical Intake Air Heater........ 4-51
How to Adjust Clock............................................3-241 How to Examine Electrolyte Level from Side of Bat-
How to Adjust Damper........................................ 3-180 tery.................................................................4-58
How to Adjust Depth to Dig.....................................6-8 How to Examine Electrolyte Level When It is Not Pos-
How to Adjust Frequency (Auto Presetting)........3-239 sible to Examine from Side of Battery............4-60
How to Adjust Idler Clearance.............................. 4-34 How to Examine Electrolyte Level When It is Possible
How to Adjust Idler Clearance Horizontally...........4-34 to Use Indicator to Examine Electrolyte Level......
How to Adjust Idler Clearance Vertically............... 4-35 .......................................................................4-60
How to Adjust Mirrors..........................................3-181 How to Examine for Looseness of Engine High-Pres-
How to Adjust Seat Cushion in Fore-After Direction.... sure Piping Clamp, Hardening of Rubber...... 4-95
.....................................................................3-180 How to Examine for Missing Fuel Spray Prevention
How to Adjust Seat Height.................................. 3-179 Cap, Hardening of Rubber.............................4-96
How to Adjust Shims at Pitch Ball.........................4-53 How to Examine Fuel Level, Add Fuel................3-160
How to Adjust Sound Balance............................ 3-240 How to Examine Function of Accumulator for Control
How to Adjust Weight on Seat............................ 3-179 Circuit and Release Internal Pressure in Hydraul-
How to Adjust Work Equipment.......................... 3-220 ic Circuit......................................................... 4-83
How to Bleed Air from Hydraulic Circuit................4-50 How to Examine Looseness and Tighten Track Shoes
How to Call Memory..............................................3-51 Bolts...............................................................4-32
How to Change Oil in Engine Oil Pan and Replace How to Examine Low-Speed Run and Acceleration of
Engine Oil Filter Cartridge............................. 4-62 Engine..........................................................3-193
How to Clean and Replace Outer Element........... 4-19 How to Examine Machine Monitor...................... 3-168
How to Clean DEF Tank........................................4-97 How to Examine Oil Level in Engine Oil Pan, Add Oil.
How to Clean DEF Tank Mounting Part................ 4-97 .....................................................................3-157
How to Clean Inside Machine............................... 4-27 How to Examine Oil Level in Final Drive Case, Add
How to Clean Inside of Cooling System................4-23 Oil.................................................................. 4-57
How to Decrease Track Tension........................... 4-31 How to Examine Oil Level in Hydraulic Tank, Add Oil..
How to Do Walk-Around Check.................... 3-150,6-7 .............................................................3-154,6-10
How to Drain Water and Sediment from Fuel Tank...... How to Examine Operation of Lamps................. 3-167
.....................................................................3-152 How to Examine Operation State of Backup Alarm.....
How to Examine After You Complete Work........ 3-227 .....................................................................3-170
How to Examine Air Conditioner Compressor Belt How to Examine Operation State of Horn...........3-169
Tension.......................................................... 4-46 How to Examine Refrigerant (Gas) Level............. 4-49
How to Examine All Tightening Points of Engine In- How to Examine Starting Condition and Unusual
take Pipe Clamps...........................................4-74 Noise of Engine........................................... 3-193
How to Examine Alternator................................... 4-85 How to Examine Starting Motor............................ 4-93
How to Examine and Adjust................................3-222 How to Examine Vibration Damper.......................4-86
How to Examine and Adjust Engine Valve Clearance.. How to Examine Water Separator, Drain Water and
.......................................................................4-85 Sediment......................................................3-153
How to Examine and Adjust Track Tension...........4-29 How to Examine Window Washer Fluid Level, Add
How to Examine and Clean Fan........................... 4-77 Fluid............................................................... 4-43
How to Examine and Clean Front Surface of Radiator How to Examine Wiper Blade............................... 4-44
.......................................................................4-28 How to Examine, Clean and Replace Air Cleaner 4-17

8-3
 INDEX

How to Fasten and Unfasten Seat Belt...............3-182 Increase Track Tension......................................... 4-29
How to Fasten Seat Belt..................................... 3-182 Inducement Strategy for Abnormalities Recurrences
How to Heat the Seat................................3-174,3-177 in 40 Hours.................................................. 3-147
How to Lift Machine............................................ 3-246 Inducement Strategy When Abnormality is Found in
How to Lubricate Equalizer Bar Center Pin.......... 4-55 Urea SCR System Devices..........................3-142
How to Lubricate Equalizer Bar Side Pin.............. 4-56 Inducement Strategy When the DEF Tank Level Be-
How to Open and Close Cover with Lock........... 3-231 comes Low...................................................3-139
How to Open and Close DEF Tank Filler Port Cover... Inspect Machine......................................................2-9
.....................................................................3-232 Install External Power Supply System.................. 6-17
How to Open and Close Fuel Filler Port Cap......3-230 Install External Power Supply System for External
How to Open and Close Radiator Grille........3-120,6-5 Power Supply Engine Preheater....................6-13
How to Operate to Prevent Dust from Entering Into Introduction............................................................. 1-5
CAB............................................................. 3-234 Invert and Replace Cutting Edge and End Bit...... 4-36
How to Park Machine..........................................3-225
How to Recline Seat....................... 3-172,3-175,3-178 J
How to Remove Sediment in Engine Room........3-168
How to Replace Accumulator (For Control Circuit)...... Joystick (Steering, Directional and Gear Shift Lever)
.......................................................................4-94 (PCCS Lever).............................................. 3-106
How to Replace DEF Hose................................... 4-99
How to Replace DEF Tank Filler Port Filter.......... 4-97 K
How to Replace Element...................................... 4-21
How to Replace Fuel Main Filter Cartridge........... 4-71 Keep Machine Clean.............................................2-10
How to Replace Fuel Prefilter Cartridge............... 4-65 Keep Work Place Clean........................................2-27
How to Replace Fuel Spray Prevention Cap........ 4-98 Komatsu Closed Crankcase Ventilation (KCCV) 3-129
How to Replace Receiver................................... 3-235 Komatsu Genuine Lubricants..................................4-2
How to Replace Ripper Point..................................6-8 Komatsu Genuine Replacement Parts....................4-2
How to Retighten Track Shoe Bolt........................ 4-32 KOMTRAX.......................................................... 3-149
How to Secure Machine......................................3-244
How to Select Window Washer Fluid.................... 2-37 L
How to Set Each Item and Save Memory............. 3-50
Language Settings................................................ 3-89
How to Shift Gears..............................................3-203
Leveling Work..................................................... 3-218
How to Start Engine..................................3-188,3-261
Load Display......................................................... 3-46
How to Start Engine in Cold Weather......... 3-190,6-20
Load onto and Unload from a Trailer.................. 3-243
How to Start Engine in Normal Weather............. 3-188
Load Preset.........................................................3-239
How to Start Machine (Travel FORWARD and RE-
Location of Engine Number Plate........................... 1-7
VERSE) and Stop Machine......................... 3-199
Location of Product Identification Number (PIN) and
How to Stop Engine............................................ 3-197
Machine Serial No. Plate................................. 1-7
How to Switch Between FORWARD and REVERSE...
Location of Safety Labels........................................2-3
.....................................................................3-207
Lock.................................................................... 3-228
How to Tilt Seat.............................. 3-173,3-175,3-178
Lock Inspection Covers...........................................4-4
How to Turn Machine During Downhill Travel..... 3-211
Low Register Range (Bass) Setting....................3-241
How to Unfasten Seat Belt..................................3-183
Lubricate Door Hinge............................................ 4-42
How to Use Brakes............................................... 2-23
Lubrication............................................ 4-55,4-56,6-10
How to Use Fuel, Coolant and Lubricants by Ambient
Lubrication Chart.....................................................7-4
Temperature.....................................................7-7
Lunch Box Fixing Belt......................................... 3-110
HST Oil Filter Clogging Caution Lamp..................3-21
HST Oil Pressure Caution Lamp...........................3-21
HST System Caution Lamp.................................. 3-20 M
Hydraulic Oil Temperature Caution Lamp............. 3-18 Machine Monitor Equipment................................... 3-5
Hydraulic Oil Temperature Gauge.........................3-35 Machine Operations and Controls................ 3-150,6-7
Machine Settings.................................................. 3-73
I Main Use of Machine.............................................. 1-5
Maintenance During Long-Term Storage............ 3-251
ID Key Information................................................ 3-90
Maintenance Interval When Diesel Fuel Mixed with
ID Key Types.......................................................3-122
Bio-Fuel is Used............................................ 4-16
If a Problem is Found............................................2-10
Maintenance of Air Conditioner.............................2-36
If Machine Monitor Shows Warning Display........3-268
Maintenance Procedure........................................4-17
In Cold Weather..........................................2-20,3-138
Maintenance Schedule......................................... 4-14

8-4
INDEX

Maintenance Schedule Table................................4-14 Power Supply Outlet............................................3-111

Maintenance Screen Setting.................................3-78 Precautions After Daily Work Ends in Cold Weather...
Maintenance Time Caution Lamp......................... 3-26 .....................................................................3-250
Make External Power Supply Cable..................... 6-15 Precautions Before Inspection and Maintenance. 2-27
Make Sure of Good Visibility.................................2-17 Precautions Before You Start Operation................. 2-9
Manual Stationary Regeneration........................ 3-133 Precautions for Blind Areas Caused by CAB and
Measure Grouser Height.....................................3-223 ROPS Structures......................................... 3-217
Measure Track Roller Diameter.......................... 3-224 Precautions for Check and Maintenance.............. 2-31
Mechanical Suspension Seat..............................3-175 Precautions for Compressed Air........................... 2-36
Message Display.......................................... 3-28,3-93 Precautions for DEF..............................................2-38
Meter Display........................................................ 3-34 Precautions for Discharged Battery.................... 3-255
Method for Measure Link Pitch........................... 3-223 Precautions for Downhill Travel.......................... 3-215
Method for Normal Turning Operation................ 3-208 Precautions for Fire Hazard and Leakage............ 2-38
Monitor Setting......................................................3-80 Precautions for Floating Operation..................... 3-216
Monitor Switch...................................................... 3-40 Precautions for High Voltage................................ 2-35
Move Machine.....................................................3-199 Precautions for High-Pressure Fuel......................2-33
Multi Gauge...........................................................3-34 Precautions for High-Pressure Grease During Track
Multi Gauge Selector Switch.................................3-56 Tension Adjustment....................................... 2-35
Precautions for High-Pressure Oil........................ 2-33
N Precautions for High-Temperature Areas..............2-33
Precautions for High-Temperature Coolant...........2-32
Names of Machine Equipment................................3-2 Precautions for High-Temperature Oil...................2-33
Names of Machine Monitor Equipment...................3-4 Precautions for Inside Operator's Compartment...2-10
No People on Attachments................................... 2-13 Precautions for Jobsite......................................... 2-16
Precautions for Long-Term Storage.................... 3-251
O Precautions for Long-Time Travel.......................3-215
Precautions for Maintenance.......................... 2-27,4-2
Oil............................................................................4-6 Precautions for Noise............................................2-35
Only Authorized Personnel................................... 2-27 Precautions for Opening and Closing Radiator Grille..
Open and Close Cap with Lock.......................... 3-229 .........................................................................4-4
Operate............................................................... 3-222 Precautions for Operation............ 2-16,2-21,3-215,6-7
Operate Counter-Rotation Turn.......................... 3-209 Precautions for Safety.............................................6-2
Operate Engine in Break-in Period..................... 3-194 Precautions for Safety-related Equipment.............. 2-9
Operate Radio.....................................................3-239 Precautions for Storage........................................ 2-38
Operating Mode.................................................... 3-44 Precautions for Transportation..............................2-25
Operating Mode Display....................................... 3-28 Precautions for Welding..................................2-31,4-2
Operating Mode Selector Switch.......................... 3-43 Precautions Related to Attachments and Options 2-15
Operation of Urea SCR System..........................3-138 Precautions Related to Protective Structures....... 2-15
Operations and Checks After You Start Engine.. 3-193 Precautions to Prevent Fire...................................2-11
Operations and Checks Before You Start Engine........ Precautions When You Add.................................. 2-38
.....................................................................3-184 Precautions When You Add DEF............................ 4-2
Operator ID........................................................... 3-90 Precautions When You Charge Battery.............. 3-259
Other Equipment.................................................3-108 Precautions When You Discard Waste Materials..2-36
Other Precautions................................................. 2-38 Precautions When You Get on or Off Machine..... 2-13
Other Trouble................................................3-262,6-9 Precautions When You Install Hydraulic Hoses...... 4-4
Outline of Maintenance........................................... 4-6 Precautions When You Install, Remove, or Store At-
tachments...................................................... 2-29
P Precautions When You Load and Unload............. 2-25
Precautions When You Move Away from Operator
Parking Brake Lever........................................... 3-104
Seat............................................................... 2-14
Parking Brake Pilot Lamp..................................... 3-29
Precautions When You Open Inspection Cover......4-4
Parking Brake System Caution Lamp................... 3-23
Precautions When You Operate Engine Inside Build-
Pedal Mode...........................................................3-45
ing.................................................................. 2-15
Pedal Mode Selector Switch................................. 3-43
Precautions When You Operate Machine............. 2-23
Periodic Replacement of Defined Life Parts... 2-37,7-2
Precautions When You Operate on Snow or Frozen
Pilot Display.......................................................... 3-27
Surfaces.........................................................2-24
Pilot Display and Meter Display............................ 3-27
Precautions When You Park Machine...................2-24
Power Button...................................................... 3-236
Precautions When You Refill Oil or Fuel................. 4-2
Power Supply for KOMTRAX..............................3-149

8-5
 INDEX

Precautions When You Stand Up from Operator's Q

Seat............................................................... 2-14
Precautions When You Start Engine.....................2-20 Quick Shift Mode.................................................3-204
Precautions When You Tow and are Towed..........2-26
Precautions When You Tow Machine..................3-253 R
Precautions When You Transport Machine.........3-242
Precautions When You Travel...............................2-22 Radiator Grille...............................................3-120,6-5
Precautions When You Travel in FORWARD and RE- Read This Manual...................................................1-2
VERSE...........................................................2-21 Rear Lamp Switch.................................................3-98
Precautions When You Travel on Slopes..............2-23 Recommended Applications............................... 3-217
Precautions When You Use Hammer................... 2-32 Recommended Brands and Qualities Other Than Ko-
Precautions When You Work at High Places........ 2-29 matsu Genuine Oils......................................... 7-8
Precautions When You Work on Loose Ground... 2-16 Recommended Fuel, Coolant, and Lubricant......... 7-4
Precautions When You Work on Machine.............2-30 Recommended Working Modes..........................3-214
Precautions When You Work on Slope............... 3-216 Recommended Working Modes for Works......... 3-212
Precautions When You Work Under Machine or Work Regeneration Performance Caution Lamp........... 3-22
Equipment......................................................2-30 Remove and Install Battery.................................3-256
Preheating Pilot Lamp...........................................3-27 Remove CAB...................................................... 3-242
Prepare for Long-Term Storage.......................... 3-251 Remove Work Equipment................................... 3-242
Prepare for Safety Operation.................................. 2-9 Replace Air Conditioner Fresh/Recirc Air Filters.. 4-68
Preset Button...................................................... 3-237 Replace DEF Filter................................................4-90
Preset Station..................................................... 3-240 Replace DEF Tank Breather Element................... 4-75
Prevent Fire...........................................................2-11 Replace Defined Life Parts................................... 4-93
Procedure to Cancel Aftertreatment Device Regener- Replace Door Damper.......................................... 4-42
ation Disable................................................ 3-137 Replace Door Wiper..............................................4-45
Procedure to Close Fuel Tank Filler Port Cap.....3-230 Replace Fresh Air Filter........................................ 4-68
Procedure to Close Radiator Grille............... 3-121,6-6 Replace Front Wiper............................................. 4-44
Procedure to Connect Jumper Cables................3-261 Replace Fuel Tank Breather Element................... 4-74
Procedure to Disconnect Jumper Cables........... 3-261 Replace Hydraulic Tank Breather Element........... 4-74
Procedure to Lock Cap with Lock....................... 3-229 Replace KCCV Filter Element...............................4-86
Procedure to Lock Cover with Lock.................... 3-231 Replace Rear Wiper..............................................4-45
Procedure to Lock DEF Tank Filler Port Cover... 3-232 Replace Recirculation Air Filter.............................4-68
Procedure to Open Cap with Lock...................... 3-229 Replace Wiper Blade............................................ 4-44
Procedure to Open Cover with Lock................... 3-231 Reply Message..................................................... 3-94
Procedure to Open DEF Tank Filler Port Cover..3-232 Retighten Master Link Connection Bolt.................4-32
Procedure to Open Fuel Tank Filler Port Cap..... 3-230 Reverse Hydraulic Fan......................................... 3-73
Procedure to Open Radiator Grille............... 3-120,6-5 REVERSE Travel Speed Control Switch.............. 3-43
Procedure to Release Internal Pressure in Hydraulic REVERSE Travel Speed Settings.............. 3-45,3-206
Circuit.............................................................4-51 Ripper Control Lever...............................................6-4
Procedure to Set Aftertreatment Device Regeneration Room Lamp Switch...............................................3-98
Disable.........................................................3-135
Procedures If Fire Occurs..................................... 2-11 S
Procedures to Delete ID Number of Registered Nor-
Safety Information...................................................1-4
mal Key (Black)............................................3-125
Safety Labels.................................................... 2-2,2-4
Procedures to Delete ID Numbers of All the Regis-
Sash Glass Intermediate Lock............................ 3-108
tered Normal Keys (Black)...........................3-126
SCR Information................................................... 3-77
Procedures to Load Machine.............................. 3-243
Screen Adjustment................................................3-80
Procedures to Register ID Number of New Normal
Seatbelt Caution Lamp......................................... 3-26
Key (Black).................................................. 3-127
See Fuel Consumption Record.............................3-64
Procedures to See ID Number of Registered Normal
See Message........................................................ 3-94
Key (Black).................................................. 3-124
See Operation Records........................................ 3-63
Procedures to Show ID Numbers of All the Regis-
See Signs and Signalman's Signals..................... 2-18
tered Normal Keys (Black)...........................3-124
Select Correct Area for Inspection and Maintenance...
Procedures to Unload Machine...........................3-245
.......................................................................2-27
Product Information.................................................1-7
Select Fuel and Lubricants by Ambient Temperature..
Prohibited Operations........................................... 2-23
.........................................................................4-5
Service Meter Location........................................... 1-8
Service Meter/Clock..............................................3-37

8-6
INDEX

Service Meter/Clock Display Selector Switch....... 3-55 U

Set Display Mode..................................................3-83
Set Display of Fuel Consumption Gauge..............3-67 Unauthorized Modification.................................... 2-15
Set Guide Line Display Mode............................... 3-84 Understand the Machine.........................................2-9
Shovel Holder......................................................3-116 Use Applicable Tools.............................................2-30
Show Warning Tag During Inspection and Mainte- Use Engine Brake............................................... 3-215
nance............................................................. 2-27 Use Handrails and Steps When You Get on or Off
Side-Cut Operation............................................. 3-219 Machine......................................................... 2-13
Sound Control Button..........................................3-237 Use Multi Gauge................................................... 3-57
Specifications..........................................................5-2 Use Warning Tags.................................................2-19
Specifications: D51EX-24............................... 5-2,6-11 User Menu............................................................ 3-60
Specifications: D51PX-24....................................... 5-3 User Menu Display Switch.................................... 3-59
Speed Range Display........................................... 3-33
Standard Tightening Torque for Bolts and Nuts.... 4-12 V
Start Engine.......................................................... 2-19
Start Engine with Jumper Cables............... 2-20,3-260 Variable Shift Mode.............................................3-205
Start Machine After Long-Term Storage............. 3-252 Visibility from Operator's Seat.................................1-5
Starting Switch...................................................... 3-95 Volume Control Button........................................ 3-236
Steer Machine.....................................................3-208
Steering Mode.......................................................3-47 W
Steering Mode Display..........................................3-30
Warning Display.................................................... 3-12
Steering System Caution Lamp............................ 3-19
Watch Gauges.................................................... 3-215
Stop Engine Before You Inspect or Do Maintenance...
Water Separator Caution Lamp............................ 3-25
.......................................................................2-28
Wear Well-Fitting Clothes and Protective Equipment..
Stop Machine...................................................... 3-202
.........................................................................2-9
Store DEF............................................................. 4-10
When Operator Identification Function is Available
Store Oil and Fuel................................................. 4-10
with SKIP....................................................... 3-90
Supply Fire Extinguisher and First Aid Kit.............2-10
When Operator Identification Function is Available
Switches................................................................3-95
Without SKIP................................................. 3-92
System Caution Lamp...........................................3-19
When Required..................................................... 4-17
System Operating Lamp..................................... 3-119
Wiper Switch......................................................... 3-97
Work Equipment Lock Lever...............................3-105
T Work Equipment Lock Pilot Lamp.........................3-29
Target Fuel Consumption Value in ECO Gauge Set- Work Equipment System Caution Lamp............... 3-19
ting................................................................. 3-70 Works of Felling Trees and Removing Stumps...3-219
Temperature Control Switch................................3-234 Works to Cut and Ditch Hard or Frozen Ground.3-219
Temporary Restoration from Inducement............3-145
Time Setting.......................................................... 3-87 Y
Tips for Longer Undercarriage Life..................... 3-222
Your Machine Serial Numbers and Distributor........ 1-8
Tool Box.............................................................. 3-116
Towing and being Towed.......................................2-26
Transportation..................................................... 3-242
Travel on Road....................................................3-242
Troubles and Procedures..............................3-253,6-9
Troubles and Procedures on Chassis................. 3-264
Troubles and Procedures on Electrical System.. 3-262
Troubles and Procedures on Engine...................3-266
Tuning/Time Adjustment Button..........................3-236
Turn Battery Disconnect Switch to OFF Position.. 2-31
Turn Machine During FORWARD Travel............ 3-208
Turn Machine Gradually During FORWARD Downhill
Travel........................................................... 3-211
Two Workers are Required for the Maintenance
When the Engine is in Operation................... 2-29

8-7
D51EX-24, D51PX-24 BULLDOZER
Form No. TEN00770-02

©2023 KOMATSU
All Rights Reserved
Printed in Japan 04-2023