.

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FOREWORD FOREWORD

FOREWORD
This manual provides rules and guidelines which will help you use this machine safely and effectively. The
precautions in this manual must be followed at all times when performing operation and maintenance. Most
accidents are caused by the failure to follow fundamental safety rules for the operation and maintenance of
machines. Accidents can be prevented by knowing beforehand conditions that may cause a hazard when
performing operation and maintenance.

WARNING
Before beginning operation or maintenance, operators and maintenance personnel must always observe the following points.

Read this manual thoroughly and understand its contents fully.

Read the safety messages and safety labels given in this manual carefully so that they should be understood fully.

Keep this manual at the storage location for the Operation and Maintenance Manual given below so that all personnel involved
in working on the machine can consult it periodically.

In case this manual should be lost or damaged, immediately contact Komatsu or your Komatsu distributor to obtain a new copy.

When you sell the machine, make sure that this manual should be provided to the new owner together with the machine.

In this manual, measurements are expressed in international standard units (SI). For the reference purpose, weight units used in
the past are also displayed in ( ).

Storage location for the Operation and Maintenance Manual:

magazine box on the left side of the operator's seat.

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FOREWORD FOREWORD

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FOREWORD FOREWORD

1-4
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FOREWORD SAFETY INFORMATION

SAFETY INFORMATION
To enable you to use this machine safely, safety precautions and labels are given in this manual and affixed to the
machine to give explanations of situations involving potential hazards and of the methods of avoiding such
situations.

Signal words

The following signal words are used to inform you that there is a potential hazardous situation that may lead to
personal injury or damage.
In this manual and on machine labels, the following signal words are used to express the potential level of hazard.

Indicates an imminently hazardous situation which, if not avoided, will result in death or
serious injury.

Indicates a potentially hazardous situation which, if not avoided, could result in death or
serious injury.

Indicates a potentially hazardous situation which, if not avoided, may result in minor or
moderate injury. This word is used also to alert against unsafe practices that may cause
property damage.

Example of safety message using signal word

WARNING
When standing up from the operator's seat, always place the lock lever in the LOCK position.
If you accidentally touch the control levers when they are not locked, this may cause a serious injury or death.

Other signal words

In addition to the above, the following signal words are used to indicate precautions that should be followed to
protect the machine or to give information that is useful to know.

This word is used for precautions that must be taken to avoid actions which could shorten
the life of the machine.

This word is used for information that is useful to know.

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SAFETY INFORMATION FOREWORD

Safety labels

Safety labels are affixed to the machine to inform the operator or maintenance worker on the spot when carrying out
operation or maintenance of the machine that may involve hazard.
This machine uses "Safety labels using words" and "Safety labels using pictograms" to indicate safety procedures.

Example of safety label using words

Safety labels using pictogram

Safety pictograms use a picture to express a level of hazardous
condition equivalent to the signal word. These safety pictograms
use pictures in order to let the operator or maintenance worker
understand the level and type of hazardous condition at all times.
Safety pictograms show the type of hazardous condition at the top
or left side, and the method of avoiding the hazardous condition at
the bottom or right side. In addition, the type of hazardous
condition is displayed inside a triangle and the method of avoiding
the hazardous condition is shown inside a circle.

Komatsu cannot predict every circumstance that might involve a potential hazard in operation and maintenance.
Therefore, the safety messages in this manual and on the machine may not include all possible safety precautions.
If any procedures or actions not specifically recommended or allowed in this manual are used, it is your responsibility
to take the necessary steps to ensure safety.
In no event should you engage in prohibited uses or actions described in this manual.

The explanations, values, and illustrations in this manual were prepared based on the latest information available
at that time. Continuing improvements in the design of this machine can lead to changes in detail which may not
be reflected in this manual. Consult Komatsu or your Komatsu distributor for the latest available information of your
machine or for questions regarding information in this manual.

The numbers in circles in the illustrations correspond to the numbers in ( ) in the text. (For example: 1 -> (1))

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FOREWORD INTRODUCTION

INTRODUCTION
This Komatsu machine is designed to be used mainly for the following work:
Digging work
Leveling work
Ditching work
Loading work
Demolition work
See the section "RECOMMENDED APPLICATIONS (PAGE 3-117)" for further details.

DIRECTIONS OF MACHINE

In this manual, the terms front, rear, left, and right refer to the travel direction as seen from the operator's seat when
the operator's seat is facing the front and the sprocket is at the rear of the machine.

BREAKING-IN THE NEW MACHINE

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 content of this manual, and pay careful attention to the following points when
breaking in the machine.
Run the engine at idle for 15 seconds after starting it. During this time, do not operate the control levers or fuel
control dial.
Idle the engine for 5 minutes after starting it up.
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.

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PRODUCT INFORMATION FOREWORD

PRODUCT INFORMATION
When requesting service or ordering replacement parts, please inform your Komatsu distributor of the following
items.

PRODUCT IDENTIFICATION NUMBER (PIN)/MACHINE SERIAL NO. PLATE

On the bottom right of the operator's cab
The design of the nameplate differs according to the territory.

ENGINE SERIAL NUMBER PLATE AND ITS LOCATION

This is on the top surface of the engine oil filter bracket.
(The additional EPA plate is the same as the engine number plate.)

EPA: Environmental Protection Agency, U.S.A.

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FOREWORD PRODUCT INFORMATION

SERVICE METER LOCATION

On top of the machine monitor

YOUR MACHINE SERIAL NUMBERS AND DISTRIBUTOR

Machine serial No.

Engine serial No.

Product identification number (PIN)

Distributor name

Address

Service Personnel

Phone/Fax

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CONTENTS FOREWORD

CONTENTS
FOREWORD 1- 1
FOREWORD 1- 2
SAFETY INFORMATION 1- 5
INTRODUCTION 1- 7
DIRECTIONS OF MACHINE 1- 7
BREAKING-IN THE NEW MACHINE 1- 7
PRODUCT INFORMATION 1- 8
PRODUCT IDENTIFICATION NUMBER (PIN)/MACHINE SERIAL NO. PLATE 1- 8
ENGINE SERIAL NUMBER PLATE AND ITS LOCATION 1- 8
SERVICE METER LOCATION 1- 9
YOUR MACHINE SERIAL NUMBERS AND DISTRIBUTOR 1- 9
SAFETY 2- 1
SAFETY INFORMATION 2- 2
SAFETY LABELS 2- 4
LOCATION OF SAFETY LABELS 2- 4
SAFETY LABELS 2- 5
SAFETY INFORMATION 2- 11
SAFETY MACHINE OPERATION 2- 20
STARTING ENGINE 2- 20
OPERATION 2- 22
TRANSPORTATION 2- 28
BATTERY 2- 29
TOWING 2- 31
LIFTING OBJECTS WITH BUCKET 2- 32
SAFETY MAINTENANCE INFORMATION 2- 33
OPERATION 3- 1
MACHINE VIEW ILLUSTRATIONS 3- 2
OVERALL MACHINE VIEW 3- 2
CONTROLS AND GAUGES 3- 3
DETAILED CONTROLS AND GAUGES 3- 5
MONITORING SYSTEM 3- 5
SWITCHES 3- 30
CONTROL LEVERS AND PEDALS 3- 35
SUN ROOF 3- 38
WINDSHIELD 3- 38
EMERGENCY EXIT FROM OPERATOR'S CAB 3- 43
DOOR LOCK 3- 43
CAP WITH LOCK 3- 44
HOT AND COOL BOX 3- 45
MAGAZINE BOX 3- 46
ASHTRAY 3- 46
AIR CONDITIONER CONTROLS 3- 47
RADIO 3- 61
AUXILIARY ELECTRIC POWER 3- 66
FUSE 3- 67
FUSIBLE LINK 3- 68
CONTROLLER 3- 68
TOOL BOX 3- 69
GREASE GUN HOLDER 3- 69

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FOREWORD CONTENTS

ACCUMULATOR 3- 70
MACHINE OPERATIONS AND CONTROLS 3- 71
BEFORE STARTING ENGINE 3- 71
STARTING ENGINE 3- 86
AFTER STARTING ENGINE 3- 90
STOPPING THE ENGINE 3- 99
MACHINE OPERATION 3-100
STEERING THE MACHINE 3-104
SWINGING 3-106
WORK EQUIPMENT CONTROLS AND OPERATIONS 3-107
WORKING MODE 3-109
PROHIBITED OPERATIONS 3-110
GENERAL OPERATION INFORMATION 3-112
TRAVELING ON SLOPES 3-114
ESCAPE FROM MUD 3-116
RECOMMENDED APPLICATIONS 3-117
BUCKET REPLACEMENT AND INVERSION 3-119
PARKING MACHINE 3-122
CHECK AFTER SHUT OFF ENGINE 3-123
MACHINE INSPECTION AFTER DAILY WORK 3-123
LOCKING 3-124
TRANSPORTATION 3-125
PRECAUTIONS FOR TRANSPORTATION 3-125
LOADING AND UNLOADING WITH TRAILER 3-126
LIFTING MACHINE 3-134
TRANSPORTATION POSTURE 3-136
COLD WEATHER OPERATION 3-139
COLD WEATHER OPERATION INFORMATION 3-139
AFTER DAILY WORK COMPLETION 3-142
AFTER COLD WEATHER SEASON 3-142
LONG TERM STORAGE 3-143
BEFORE STORAGE 3-143
DURING STORAGE 3-143
AFTER STORAGE 3-143
STARTING MACHINE AFTER LONG-TERM STORAGE 3-144
TROUBLES AND ACTIONS 3-145
RUNNING OUT OF FUEL 3-145
PHENOMENA THAT ARE NOT FAILURES 3-146
TOWING THE MACHINE 3-147
LIGHTWEIGHT TOWING HOLE 3-148
SEVERE JOB CONDITION 3-148
DISCHARGED BATTERY 3-149
OTHER TROUBLE 3-153
MAINTENANCE 4- 1
MAINTENANCE INFORMATION 4- 2
OUTLINE OF SERVICE 4- 4
HANDLING OIL, FUEL, COOLANT, AND PERFORMING OIL CLINIC 4- 4
ELECTRIC SYSTEM MAINTENANCE 4- 7
WEAR PARTS 4- 8
WEAR PARTS LIST 4- 8

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CONTENTS FOREWORD

LUBRICANTS, FUEL AND COOLANT SPECIFICATIONS 4- 9

TIGHTENING TORQUE SPECIFICATIONS 4- 13
TIGHTENING TORQUE LIST 4- 13
SAFETY CRITICAL PARTS 4- 14
SAFETY CRITICAL PARTS LIST 4- 14
MAINTENANCE SCHEDULE 4- 15
MAINTENANCE SCHEDULE CHART 4- 15
MAINTENANCE INTERVAL FOR HYDRAULIC BREAKER 4- 17
MAINTENANCE PROCEDURE 4- 18
INITIAL 250 HOURS MAINTENANCE (ONLY AFTER THE FIRST 250 HOURS) 4- 18
INITIAL 1000 HOURS MAINTENANCE (ONLY AFTER THE FIRST 1000 HOURS) 4- 18
WHEN REQUIRED 4- 19
CHECK BEFORE STARTING 4- 44
EVERY 50 HOURS MAINTENANCE 4- 45
EVERY 250 HOURS MAINTENANCE 4- 46
EVERY 500 HOURS MAINTENANCE 4- 53
EVERY 1000 HOURS MAINTENANCE 4- 66
EVERY 2000 HOURS MAINTENANCE 4- 73
EVERY 4000 HOURS MAINTENANCE 4- 76
EVERY 5000 HOURS MAINTENANCE 4- 78
EVERY 8000 HOURS MAINTENANCE 4- 80
SPECIFICATIONS 5- 1
SPECIFICATIONS 5- 2
ATTACHMENTS AND OPTIONS 6- 1
GENERAL PRECAUTIONS FOR SAFETY 6- 2
PRECAUTIONS WHEN SELECTING 6- 2
READ THE INSTRUCTION MANUAL THOROUGHLY 6- 2
PRECAUTIONS WHEN REMOVING OR INSTALLING 6- 2
PRECAUTIONS WHEN USING 6- 2
MACHINE READY FOR ATTACHMENT 6- 3
LOCATIONS 6- 3
HYDRAULIC CIRCUIT 6- 7
ATTACHMENT REMOVAL AND INSTALLATION 6- 11
ATTACHMENT OPERATIONS 6- 13
LONG TERM STORAGE 6- 15
SPECIFICATIONS 6- 15
ATTACHMENT GUIDE 6- 16
ATTACHMENT COMBINATIONS 6- 16
RECOMMENDED ATTACHMENT OPERATIONS 6- 18
HYDRAULIC BREAKER 6- 18
LOADING SHOVEL 7- 1
EXPLANATION OF COMPONENTS 7- 2
SWITCHES 7- 2
OPERATIONS 7- 5
OPERATION OF WORK EQUIPMENT 7- 5
PRECAUTIONS DURING OPERATION 7- 7
EXCAVATOR WORK 7- 11
PRECAUTIONS WHEN DISASSEMBLING MACHINE 7- 12
RELEASING PRESSURE 7- 12
TRANSPORTATION 7- 13

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FOREWORD CONTENTS

MACHINE CONFIGURATION FOR TRANSPORT 7- 13

MAINTENANCE 7- 17
CHECK BEFORE STARTING 7- 17
EVERY 10 HOURS MAINTENANCE 7- 18
SPECIFICATION 7- 19
COMBINATION OF WORK EQUIPMENT 7- 21
COMBINATION OF WORK EQUIPMENT 7- 21
INDEX 8- 1

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SAFETY INFORMATION SAFETY

SAFETY INFORMATION
SAFETY LABELS 2- 4
LOCATION OF SAFETY LABELS 2- 4
SAFETY LABELS 2- 5

SAFETY INFORMATION
Safety rules 2- 11
If problems are found 2- 11
Working wear and personal protective items 2- 11
Fire extinguisher and first aid kit 2- 11
Safety equipment 2- 11
Keep machine clean 2- 12
Keep operator's compartment clean 2- 12
Leaving operator's seat with lock 2- 12
Handrails and steps 2- 13
Precautions when working in high place 2- 13
Mounting and dismounting 2- 13
No persons on attachments 2- 13
Do not get caught in articulated portion 2- 14
Burn prevention 2- 14
Fire prevention and explosion prevention 2- 15
Action if fire occurs 2- 16
Windshield washer fluid 2- 16
Falling objects, flying objects and intruding objects prevention 2- 16
Attachment installation 2- 16
Attachment combinations 2- 16
Cab window glasses 2- 16
Unauthorized modifications 2- 17
Safety at jobsite 2- 17
Working on loose ground 2- 17
Distance to high voltage cables 2- 18
Ensure good visibility 2- 18
Ventilation for enclosed area 2- 19
Signalman's signal and signs 2- 19
Emergency exit from operator's cab 2- 19
Asbestos dust hazard prevention 2- 19

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SAFETY SAFETY INFORMATION

SAFETY MACHINE OPERATION 2- 20

STARTING ENGINE 2- 20
Checks before starting engine 2- 20
Safety rules for starting engine 2- 21
Starting engine in cold weather 2- 21
OPERATION 2- 22
Checks before operation 2- 22
Safety rules for changing machine directions 2- 22
Safety rules for traveling 2- 23
Traveling on slopes 2- 23
Operations on slopes 2- 24
Prohibited operations 2- 24
Operations on snow 2- 26
Parking machine 2- 27
TRANSPORTATION 2- 28
Loading and unloading 2- 28
Shipping the machine 2- 28
BATTERY 2- 29
Battery hazard prevention 2- 29
Starting engine with booster cables 2- 30
TOWING 2- 31
Safety rules for towing 2- 31
LIFTING OBJECTS WITH BUCKET 2- 32
Safety rules for lifting objects 2- 32

SAFETY MAINTENANCE INFORMATION 2- 33

Warning Tag 2- 33
Keep Work Place Clean and Tidy 2- 33
Appoint Leader when Working with Others 2- 33
Stop Engine Before Carrying Out Maintenance 2- 34
Two Workers for Maintenance when Engine is Running 2- 35
Proper Tools 2- 35
Accumulator, Gas spring 2- 36
Personnel 2- 36
Attachments 2- 36
Work Under the Machine 2- 36
Noise 2- 36
When Using Hammer 2- 37
Welding Works 2- 37
Removing Battery Terminals 2- 37
Safety First when Using High-pressure Grease to Adjust Track Tension 2- 37
Do Not Disassemble Recoil Springs 2- 37
Safety Rules for High-pressure Oil 2- 38
Safety Handling High-pressure Hoses 2- 38
Waste Materials 2- 38
Air Conditioner Maintenance 2- 38
Compressed Air 2- 39
Periodic Replacement of Safety Critical Parts 2- 39

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SAFETY LABELS SAFETY

SAFETY LABELS
The following warning signs and safety labels are used on this machine.
Be sure that you fully understand the correct position and content of labels.
To ensure that the content of labels can be read properly, be sure that they are in the correct place and always
keep them clean. When cleaning them, do not use organic solvents or gasoline. These may cause the labels to
peel off.
There are also other labels in addition to the warning signs and safety labels. Handle those labels in the same
way.
If the labels are damaged, lost, or cannot be read properly, replace them with new ones. For details of the part
numbers for the labels, see this manual or the actual label, and place an order with Komatsu distributor.

LOCATION OF SAFETY LABELS

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SAFETY SAFETY LABELS

SAFETY LABELS
(1) Caution for operation, inspection, and maintenance
(09651-A0641)

(2) Caution before operating (09802-03000)

(3) Caution for leaving operator's seat (09654-A0641)

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SAFETY LABELS SAFETY

(4) Caution for going close to electrical cables (09801-A0641)

(5) Caution when opening or closing front window

(09839-03000)

(6) Precautions when stowing front window (09803-A0481)

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SAFETY SAFETY LABELS

(7) Precautions when oil is hot (09653-A0481)

(8) Precautions when coolant is hot (09668-A0481)

(9) Caution when handling accumulator (09659-A057B)

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SAFETY LABELS SAFETY

(10) Caution when adjusting track tension (09657-A0881)

(11) Caution for handling cable (09808-A0881)

(12) Stopping rotation for inspection and maintenance

(09667-A0481)

(13) Explanation of method for emergency escape (20Y-00-22880)

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SAFETY SAFETY LABELS

(14) Caution against falling (09805-A0881)

(15) Caution against falling (09805-C0881)

(16) Prohibited to enter within swing range (09133-A3281)

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SAFETY LABELS SAFETY

(17) Bware of work equipment (09134-A1681)

(18) Prohibition of jump start (09842-A0481)

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SAFETY SAFETY INFORMATION

SAFETY INFORMATION
SAFETY RULES
Only trained and authorized personnel can operate and maintain the machine.
Follow all safety rules, precautions and instructions when operating or performing maintenance on the machine.
If you are under the influence of alcohol or medication, your ability to safely operate or repair your machine may
be severly impaired putting yourself and everyone else on your jobsite in danger.
When working with another operator or with a person on worksite traffic duty, be sure that all personnel
understand all hand signals that are to be used.

IF PROBLEMS ARE FOUND

If you find any problems 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 person in charge
and have the necessary action taken. Do not operate the machine until the problem has been corrected.

WORKING WEAR AND PERSONAL PROTECTIVE ITEMS

Do not wear loose clothing and accessories. There is a hazard that they may catch on control levers or other
protruding parts.
If you have long hair and it hangs out from your hard hat, there
is a hazard that it may get caught up in the machine, so tie your
hair up and be careful not to let it get caught.
Always wear a hard hat and safety shoes. If the nature of the
work requires it, wear safety glasses, mask, gloves, ear plugs,
and safety belt when operating or maintaining the machine.
Check that all protective equipment functions properly before
using it.

FIRE EXTINGUISHER AND FIRST AID KIT

Always follow the precautions below to prepare for action if any injury 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 in emergencies.
Carry out periodic inspection and maintenance to ensure that
the fire extinguisher can always be used.
Provide a first aid kit in the storage point. Carry out periodic
checks and add to the contents if necessary.

SAFETY EQUIPMENT
Be sure that all guards and covers are in their proper position. Have guards and covers repaired immediately if
they are damaged.
Understand the method of use of safety features and use them properly.
Never remove any safety features. Always keep them in good operating condition.

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SAFETY INFORMATION SAFETY

KEEP MACHINE CLEAN

If water gets into the electrical system, there is a hazard that it
will cause malfunctions or misoperation. Do not use water or
steam to wash the electrical system (sensors, connectors).
If inspection and maintenance is carried out when the machine
is still dirty with mud or oil, there is a hazard that you will slip and
fall, or that dirt or mud will get into your eyes. Always keep the
machine clean.

KEEP OPERATOR'S COMPARTMENT CLEAN

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 serious
accident.
Do not leave parts or tools lying around the operator's compartment.
Do not stick suction pads to the window glass. Suction pads act as a lens and may cause fire.
Do not use cellular telephones inside the operator's compartment when driving or operating the machine.
Never bring any dangerous objects such as flammable or explosive items into the operator's compartment.

LEAVING OPERATOR'S SEAT WITH LOCK

Before standing up from the operator's seat (such as when
opening or closing the front window or roof window, or when
removing or installing the bottom window, or when adjusting the
operator's seat), always lower the work equipment completely to
the ground, set lock lever (1) securely to the LOCK position (L),
then stop the engine. If you accidentally touch the control levers
or control pedals when they are not locked, there is a hazard that
the machine may suddenly move and cause serious injury or
property damage.

When leaving the machine, always lower the work equipment

completely to the ground, set lock lever (1) securely to the LOCK
position (L), then stop the engine. Use the key to lock all the
equipment. Always remove the key, take it with you, and keep it
in the specified place.

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SAFETY SAFETY INFORMATION

HANDRAILS AND STEPS

To prevent personal injury caused by slipping or falling off the machine, always do as follows.
Use the handrails and steps marked by arrows in the diagram on
the right when getting on or off the machine.

To ensure safety, always face the machine and maintain

three-point contact (both feet and one hand, or both hands and
one foot) with the handrails and steps (including the track shoe)
to ensure that you support yourself.
Do not grip the control levers or lock lever when getting on or off
the machine.
Never climb on the engine hood or covers where there are no
non-slip pads.
Before getting on or off the machine, check the handrails and
steps (including the track shoe). If there is any oil, grease, or
mud on the handrails or steps (including the track shoe), wipe it
off immediately. Always keep these parts clean. Repair any
damage and tighten any loose bolts.
Do not get on or off the machine while holding tools in your hand.

PRECAUTIONS WHEN WORKING IN HIGH PLACES

When working at high places, use a step ladder or other stand to ensure that the work can be carried out safely.

MOUNTING AND DISMOUNTING

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 PERSONS ON ATTACHMENTS
Never let anyone ride on the work equipment, or other attachments. There is a hazard of falling and suffering serious
injury.

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SAFETY INFORMATION SAFETY

DO NOT GET CAUGHT IN ARTICULATED PORTION

The clearance around the work equipment will change according to the movement of the link. If you get caught, this
may lead to serious personal injury. Do not allow anyone to approach any rotating or telescoping part.

BURN PREVENTION
Hot coolant
To prevent burns from hot water or steam spurting out when
checking or draining the coolant, wait for the water to cool to a
temperature where it is possible to touch the radiator cap by
hand before starting the operation. Even when the coolant has
cooled down, loosen the cap slowly to relieve the pressure
inside the radiator before removing the cap.
Hot oil
To prevent burns from hot oil spurting out when checking or
draining the oil, wait for the oil to cool to a temperature where it
is possible to touch the cap or plug by hand before starting the
operation. Even when the oil has cooled down, loosen the cap
or plug slowly to relieve the internal pressure before removing
the cap or plug.

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SAFETY SAFETY INFORMATION

FIRE PREVENTION AND EXPLOSION PREVENTION

Fire caused by fuel or oil
Fuel, oil, antifreeze, and window washer liquid are particularly
flammable and can be hazardous. To prevent fire, always
observe the following:
Do not smoke or use any flame near fuel or oil.
Stop the engine before refueling.
Do not leave the machine while adding fuel or oil.
Tighten all fuel and oil caps securely.
Do not spill fuel on overheated surfaces or on parts of the
electrical system.
Use well-ventilated areas for adding or storing oil and fuel.
Keep oil and fuel in the determined place and do not allow
unauthorized persons to enter.
After adding fuel or oil, wipe up any spilled fuel or oil.
When carrying out grinding or welding work on the chassis,
move any flammable materials to a safe place before
starting.
When washing parts with oil, use a non-flammable oil. Diesel
oil and gasoline may catch fire, so do not use them.
Put greasy rags and other flammable materials into a safe
container to maintain safety at the work place.
Do not weld or use a cutting torch to cut any pipes or tubes
that contain flammable liquids.

Fire caused by accumulation of flammable material.

Remove any dry leaves, chips, pieces of paper, dust, or any other flammable materials accumulated or affixed
around the engine, exhaust manifold, muffler, or battery, or inside the undercovers.

Fire coming from electric wiring

Short circuits in the electrical system can cause fire.
Always keep electric wiring connections clean and securely tightened.
Check the wiring every day for looseness or damage. Tighten any loose connectors or wiring clamps. Repair
or replace any damaged wiring.

Fire coming from hydraulic line

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. This may lead to damage to the
hoses, and cause high-pressure oil to spurt out, leading to fire damage or serious injury.

Explosion caused by lighting equipment

When checking fuel, oil, battery electrolyte, window washer fluid, or coolant, always use lighting with
antiexplosion specifications. If such lighting equipment is not used, there is danger of explosion that may cause
serious injury.
When taking the electrical power for the lighting from the machine itself, follow the instructions in of "AUXILIARY
ELECTRIC POWER (PAGE 3-66)".

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.

SAFETY INFORMATION SAFETY

ACTION IF FIRE OCCURS

If a fire occurs, escape from the machine as follows.
Turn the start switch OFF to stop the engine.
Use the handrails and steps to get off the machine.

WINDSHIELD WASHER FLUID

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

FALLING OBJECTS, FLYING OBJECTS AND INTRUDING OBJECTS PREVENTION

On jobsites where there is a hazard that falling objects, flying
objects, or intruding objects may hit or enter the operator's cab,
consider the operating conditions and install the necessary guards
to protect the operator.
When carrying out demolition or breaker operations, install a
front guard and use a laminated coating sheet on the front glass.
When working in mines or quarries where there is a hazard of
falling rock, install FOPS (Falling Objects Protective Structure)
and a front guard, and use a laminated coating sheet on the front
glass.
When carrying out the above operations, always close the front
window. In addition, always ensure that by standers are a safe
distance away and are not in hazard from falling or flying
objects.
The above recommendations assume that the conditions are for
standard operations, but it may be necessary to add additional
guards according to the operating conditions on the jobsite.
Always contact your Komatsu distributor for advice.

ATTACHMENT INSTALLATION
When installing optional parts or attachments, there may be problems with safety or legal restrictions. Therefore
contact your Komatsu distributor for advice.
Any injuries, accidents, or product failures resulting from the use of unauthorized attachments or parts will not be
the responsibility of Komatsu.
When installing and using optional attachments, read the instruction manual for the attachment, and the general
information related to attachments in this manual.

ATTACHMENT COMBINATIONS
Depending on the type or combination of work equipment, there is a hazard that the work equipment may hit the cab
or other parts of the machine. Before using unfamiliar work equipment, check if there is any hazard of interference,
and operate with caution.

CAB WINDOW GLASSES

If a pane of the cab window on the work equipment side is broken, the work equipment may directly hit the
operator. In that case, stop the machine immediately and replace the broken pane with new one.
The ceiling window is made of organic glass (polycarbonate), and as such it is apt to break easily when receiving
damage on the surface, thereby deteriorating its protective characteristic. If there is a crack or damage caused
by a fallen rock, or when any sign of them is noticed, replace it with a new window.

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SAFETY SAFETY INFORMATION

UNAUTHORIZED MODIFICATIONS
If this machine is modified without permission from Komatsu, there is danger that problems may occur with safety
and that this may lead to serious personal injury. Modifications may have an adverse effect on items such as
machine strength and visibility. Before making any modifications, please consult your Komatsu distributor.
Komatsu cannot take any responsibility for accidents, failures, or damage caused by modifications not authorized
by Komatsu.

SAFETY AT JOBSITE
Before starting operations, thoroughly check the area for any unusual conditions that could be dangerous.
When carrying out operations near combustible materials such as thatched roofs, dry leaves or dry grass, there
is a hazard of fire, so be careful when operating.
Check the terrain and condition of the ground at the worksite, and determine the safest method of operation. Do
not operate where there is a hazard of landslides or falling rocks.
If water lines, gas lines, or high-voltage electrical lines may be
buried under the worksite, contact each utility and identify their
locations. Be careful not to sever or damage any of these lines.
Take action to prevent unauthorized people from approaching
the jobsite.
When working on public roads, position flagmen and erect
barriers to ensure the safety of passing traffic and pedestrians.
When traveling or operating in shallow water or on soft ground,
check the shape and condition of the bedrock, and the depth
and speed of flow of the water before starting operations.

WORKING ON LOOSE GROUND

Avoid traveling or operating your machine too close to the edge of cliffs, overhangs, 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 after heavy rain or blasting or after
earthquakes is weak in these areas.
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.

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SAFETY INFORMATION SAFETY

DISTANCE 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 injury or
property damage. On jobsites where the machine may go close to
electric cables, always do as follows.
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, which may cause serious burns or even death. Always
Voltage of Cables Safety Distance
maintain a safe distance (see the table on the right) between the 100 V - 200 V Over 2 m (7 ft)
machine and the electric cable. Check with the local power 6,600 V Over 2 m (7 ft)
company about safe operating procedure before starting 22,000 V Over 3 m (10 ft)
operations. 66,000 V Over 4 m (14 ft)
To prepare for any possible emergencies, wear rubber shoes 154,000 V Over 5 m (17 ft)
and gloves. Lay a rubber sheet on top of the seat, and be careful
187,000 V Over 6 m (20 ft)
not to touch the chassis with any exposed part of your body.
275,000 V Over 7 m (23 ft)
Use a signalman to give warning if the machine approaches too
close to the electric cables. 500,000 V Over 11 m (36 ft)
When carrying out operations near high voltage cables, do not
let anyone near the machine.
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, do not let anyone near the machine.

ENSURE GOOD VISIBILITY

This machine is equipped with mirrors to improve the visibility, but even with mirrors, there are places, which cannot
be seen from the operator's seat, so always be careful when operating.
When operating or traveling in places with poor visibility, if it is impossible to confirm the condition of the job side or
obstacle is in the area around the machine, there is danger that the machine may suffer damage or the operator may
suffer serious personal injury. When operating or traveling in places with poor visibility, always observe the following
items strictly.
If the visibility cannot be sufficiently assured, position a flagman if necessary. The operator should pay careful
attention to the signs and follow the instructions of the flagman.
The signals should be given only by one flagman.
When working in dark places, turn on the working lamps and front lamps of the machine, and if necessary, set
up additional lighting in the area.
Stop operations if there is poor visibility, such as in fog, snow, rain, or sand storms.
Check the mirrors on the machine before starting operations every day. Clean off any dirt and adjust the view
to ensure good visibility.

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SAFETY SAFETY INFORMATION

VENTILATION FOR ENCLOSED AREA

Exhaust fumes from the engine can kill.
If it is necessary to start the engine within an enclosed area, or
when handling fuel, flushing oil, or paint, open the doors and
windows to ensure that adequate ventilation is provided to
prevent gas poisoning.

SIGNALMAN'S SIGNAL AND SIGNS

Set up signs to inform of road shoulders and soft ground. If the visibility is not good, position a signalman if
necessary. Operators should pay careful attention to the signs and follow the instructions from the signalman.
Only one signalman should give signals.
Make sure that all workers understand the meaning of all signals and signs before starting work.

EMERGENCY EXIT FROM OPERATOR'S CAB

If for some reason, the cab door does not open, use the rear window as an emergency escape. For details, see
"EMERGENCY EXIT FROM OPERATOR'S CAB (PAGE 3-43)" in this manual.

ASBESTOS DUST HAZARD PREVENTION

Asbestos dust in the air can cause lung cancer if it is inhaled. There
is danger of inhaling asbestos when working on jobsites handling
demolition work or work handling industrial waste. Always observe
the following.
Spray water to keep down the dust when cleaning. Do not use
compressed air for cleaning.
If there is danger that there may be asbestos dust in the air,
always operate the machine from an upwind position. All
workers should use an approved respirator.
Do not allow other persons to approach during the operation.
Always observe the rules and regulations for the work site and
environmental standards.
This machine does not use asbestos, but there is a danger that imitation parts may contain asbestos, so always use
genuine Komatsu parts.

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SAFETY MACHINE OPERATION SAFETY

SAFETY MACHINE OPERATION

STARTING ENGINE
If there is a warning tag hanging from the work equipment control
lever, do not start the engine or touch the levers .

CHECKS BEFORE STARTING ENGINE

Carry out the following checks before starting the engine at the beginning of the day's work.
Remove all dirt from the surface of the window glass to ensure a good view.
Remove all dirt from the surface of the lens of the front lamps and working lamps, and check that they light up
correctly.
Check the coolant level, fuel level, and oil level in engine oil pan, check for clogging of the air cleaner, and check
for damage to the electric wiring.
Adjust the operator's seat to a position where it is easy to carry out operations, and check that there is no damage
or wear to the seat belt or mounting clamps.
Check the operation of the instruments and gauges, check the angle of the mirror, and check that the control
levers are all at the Neutral position.
Before starting the engine, check that lock lever (1) is in LOCK
position (L).
Adjust the mirrors so that the rear of the machine can be seen
clearly from the operator's seat.
When adjusting, see "Rearview Mirrors (PAGE 3-81)".
Check that there are no persons or obstacles above, below, or
in the area around the machine.

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SAFETY SAFETY MACHINE OPERATION

SAFETY RULES FOR STARTING ENGINE

Start and operate the machine only while seated.
Do not attempt to start the engine by short-circuiting the engine starting circuit. Such an act may cause a serious
bodily injury or fire.
When starting the engine, sound the horn as a warning.
Do not allow anyone apart from the operator to ride on the machine.

STARTING ENGINE IN COLD WEATHER

Carry out the warming-up operation thoroughly. If the machine is not thoroughly warmed up before the control
levers or control pedals are operated, the reaction of the machine will be slow or the machine may move in a way
not expected by the operator. Particularly in cold weather, be sure to carry out the warming-up operation
thoroughly.
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.

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SAFETY MACHINE OPERATION SAFETY

OPERATION

CHECKS BEFORE OPERATION

When carrying out the checks, move the machine to a wide area where there are no obstructions, and operate
slowly. Do not allow anyone near the machine.
Always fasten your seat belt.
Check that the movement of the machine matches the display on the control pattern card. If it does not match,
replace it immediately with the correct control pattern card.
Check the operation of the work equipment, traval system and swing system.
Check for any problem in the sound of the machine, vibration, heat, smell, or gauges; check also that there is no
leakage of oil or fuel.
If any problem is found, carry out repairs immediately.

SAFETY RULES FOR CHANGING MACHINE DIRECTIONS

Always operate the machine only when seated.
Do not allow anyone apart from the operator to ride on the
machine.
Check that the travel alarm works properly.
Always lock the door and windows of the operator's
compartment in position (open or closed).
On jobsites where there is a hazard of flying objects or of objects
entering the operator's compartment, check that the door and
windows are securely closed.
If there is an area to the rear of the machine which cannot be
seen, position a signal person. Take special care not to hit other
machines or people when turning or swinging the machine.
Before travelling, sound the horn to warn people in the area.
Before travelling, check again that there is no one in the
surrounding area, and that there are no obstacles.

Before traveling, position the upper structure so that the

sprocket (1) is at the rear of the operator's cab. If the sprocket (1)
is at the front of the operator's cab, the machine makes a
movement reverse to the control lever movement (for example,
forward becomes reverse, and left becomes right). Be careful to
avoid such a reverse movement of the machine.

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SAFETY SAFETY MACHINE OPERATION

SAFETY RULES FOR TRAVELING

When traveling on level ground, keep the work equipment at a
height of 40 to 50 cm (16 to 20 in) from the ground.
If the work equipment blocks the view and it is difficult to travel
in safety, raise the work equipment to a greater height.
When traveling on rough ground, travel at low speed and do not
operate the steering suddenly. There is danger that the machine
may turn over. The work equipment may hit the ground surface
and cause the machine to lose its balance, or may damage the
machine or structures in the area.
When traveling on rough ground or steep slopes, if the machine
is equipped with auto-deceleration, always turn the
auto-deceleration switch OFF (cancel).
Avoid traveling over obstacles when possible. If the machine
has to travel over an obstacle, keep the work equipment close
to the ground and travel at low speed. Never travel over
obstacles which make the machine tilt strongly to one side.
When traveling or carrying out operations, always keep a safe
distance from people, structures, or other machines to avoid
coming into contact with them.
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 work equipment hit anything.

TRAVELING ON SLOPES
To prevent the machine from tipping over or slipping to the side,
always do as follows.
Keep the work equipment approx. 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.
When traveling uphill, set the machine with the operator's seat
on the uphill side; when traveling downhill, set the operator's
seat on the downhill side. Check that the ground under the
machine is safe when traveling.

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SAFETY MACHINE OPERATION SAFETY

When traveling up a steep slope, extend the work equipment to

the front to improve the balance, keep the work equipment
approximately 20 to 30 cm (8 to 12 in) above the ground, and
travel at low speed.
When traveling downhill, lower the engine speed, keep the
travel lever close to the neutral position, and travel at low speed.

Always travel straight up or down a slope. Traveling at an angle

or across the slope is extremely dangerous.
Do not turn on slopes or travel across slopes. Always go down
to a flat place to change the position of the machine, then travel
on to the slope again.
Travel on grass, fallen leaves, or wet steel plates with low
speed. Even with slight slopes there is a hazard that the
machine may slip.

OPERATIONS ON SLOPES
When working on slopes, there is a hazard that the machine may lose its balance and turn over when the swing
or work equipment are operated. This may lead to serious injury or property damage, so always provide a stable
place when carrying out these operations, and operate carefully.
Do not swing the work equipment from the uphill side to the
downhill side when the bucket is loaded. This operation is
dangerous, and may cause the machine to tip over.
If the machine has to be used on a slope, pile the soil to make
a platform (A) that will keep the machine as horizontal as
possible.

PROHIBITED OPERATIONS
Never dig the work face under an overhang. There is a hazard
that rocks may fall or that the overhang may collapse and fall on
top of the machine.

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SAFETY SAFETY MACHINE OPERATION

Do not excavate too deeply under the front of the machine. The
ground under the machine may collapse and cause the machine
to fall.

To make it easier to escape if there is any problem, set the

tracks at right angles to the road shoulder or cliff with the
sprocket at the rear when carrying out operations.

Do not carry out demolition work under the machine. There is a

hazard that the machine may become unstable and tip over.
When working on or from the top of buildings or other structures,
check the strength and the structure before starting operations.
There is a hazard of the building collapsing and causing serious
injury or damage.

When carrying out demolition work, do not carry out demolition

above your head. There is a hazard of broken parts falling or of
the building collapsing and causing serious injury or property
damage.

Do not use the impact force of the work equipment for breaking
work. There is a hazard of damage to the work equipment, or a
hazard of serious personal injury being caused by flying pieces
of broken materials, or of the machine tipping over due to
reaction from the impact.
Generally speaking, the machine is more liable to overturn when
the work equipment is at the side than when it is at the front or
rear.

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SAFETY MACHINE OPERATION SAFETY

When using a breaker or other heavy work equipment, there is a hazard of the machine losing its balance and
tipping over. When operating on flat ground as well as on slopes.
Do not suddenly lower, swing, or stop the work equipment.
Do not suddenly extend or retract the boom cylinder. There is a hazard that impact will cause the machine to
tip over.
Do not pass the bucket over the head of other workers or over the operator's seat of dump trucks or other hauling
equipment. The load may spill or the bucket may hit the dump truck and cause serious injury or property damage.

OPERATIONS ON SNOW
Snow-covered or frozen surfaces are slippery, so be extremely careful when traveling or operating the machine,
and do not operate the levers suddenly. Even a slight slope may cause the machine to slip, so be particularly
careful when working on slopes.
With frozen ground surfaces, the ground becomes soft when the temperature rises, and this may cause the
machine to tip over.
If the machine enters deep snow, there is a hazard that it may tip over or become buried in the snow. Be careful
not to leave the road shoulder or to get trapped in a snow drift.
When clearing snow, the road shoulder and objects placed beside the road are buried in the snow and cannot be
seen. There is a hazard of the machine tipping over or hitting covered objects, so always carry out operations
carefully.

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SAFETY SAFETY MACHINE OPERATION

PARKING MACHINE
Park the machine on firm, level ground.
Select a place where there is no hazard of falling rocks or
landslides, or of flooding if the land is low.
Lower the work equipment completely to the ground.

When leaving the machine, set lock lever (1) to the LOCK
position (L), then 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
moving the machine. Always remove the key, take it with you,
and leave it in the specified place.
If it is necessary to park the machine on a slope, always do as
follows.
Set the bucket on the downhill side, then dig it into the
ground.
Put blocks under the tracks to prevent the machine from
moving.

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SAFETY MACHINE OPERATION SAFETY

TRANSPORTATION

LOADING AND UNLOADING

When loading or unloading the machine, mistaken operation may
bring the hazard of the machine tipping over or falling, so particular
care is necessary. Always do as follows.
Perform loading and unloading on firm, level ground only.
Maintain a safe distance from the edge of the road or cliff.
Never use the work equipment to load or unload the machine.
There is danger that the machine may fall or tip over.
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.
Be sure the ramp surface is clean and free of grease, oil, ice and loose materials. Remove dirt from
machine-tracks. On a rainy day, in particular, be extremely careful since the ramp surface is slippery.
Turn the auto-decelerator switch OFF (auto-deceleration function released).
Run the engine at low speed and travel slowly.
When on the ramps, do not operate any lever except for the travel lever.
Never correct your steering on the ramps. If necessary, drive off the ramps, correct the direction, then enter the
ramps again.
The center of gravity of the machine will change suddenly at the joint between the ramps and the track or trailer,
and there is danger of the machine losing its balance. Travel slowly over this point.
When loading or unloading to an embankment or platform, make sure that it has suitable width, strength, and
grade.
When swinging the upper structure on the trailer, the trailer is unstable, so pull in the work equipment and swing
slowly.
For machines equipped with a cab, always lock the door after boarding the machine. If this is not done, the door
may suddenly open during transportation.
Refer to "TRANSPORTATION (PAGE 3-125)".

REMARK
(1) Blocks (2) Ramp (3) Center line of trailer (4) Angle for setting ramps

SHIPPING THE MACHINE

When shipping the machine on a trailer, do as follows.
The weight, transportation height, and overall length of the machine differ according to the work equipment, so
be sure to confirm the dimensions.
When passing over bridges or structures on private land, check first that the structure is strong enough to support
the weight of the machine. When traveling on public roads, check first with the relevant authorities and follow their
instructions.
For details of the shipping procedure, see "TRANSPORTATION (PAGE 3-125)" in the OPERATION section.

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SAFETY SAFETY MACHINE OPERATION

BATTERY

BATTERY HAZARD PREVENTION

Battery electrolyte contains sulphuric acid, and batteries generate flammable hydrogen gas, which may explode.
Mistaken handling can lead to serious injury or fire. For this reason, always observe the following precautions.
Do not use or charge the battery if the battery electrolyte level is below the LOWER LEVEL line. This may cause
an explosion. Check the battery electrolyte level periodically and add distilled water to bring the electrolyte level
to the UPPER LEVEL line.
When working with batteries, always wear safety glasses and rubber gloves.
Never smoke or use any flame near the battery.

If you spill acid on your clothes or skin, immediately flush the

area with large amount of water.
If acid gets into your eyes, flush them immediately with large
amount of water and seek medical attention.

Before working with batteries, turn the starting switch to the OFF position.

As there is a hazard that sparks will be generated, always do as follows.

Do not let tools or other metal objects make any contact between the battery terminals. Do not leave tools or other
metal objects lying around near the battery.
When disconnecting the battery terminals, wait for approx. one minute after turning off the engine starting switch
key, and be sure to disconnect the grounding terminal (negative (-) terminal) first. Conversely, when connecting
them, begin with the positive (+) terminal and then the grounding (-) terminal. Make sure that all the terminals are
connected securely.
Flammable hydrogen gas is generated when the battery is charged, so remove the battery from the chassis, take
it to a well-ventilated place, and remove the battery caps before charging it.
Tighten the battery caps securely.
Install the battery securely to the determined place.

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SAFETY MACHINE OPERATION SAFETY

STARTING ENGINE WITH BOOSTER CABLES

If any mistake is made in the method of connecting the booster
cables, it may cause the battery to explode, so always do as
follows.
When starting with a booster cable, carry out the starting
operation with two workers (one worker sitting in the operator's
seat and the other working with the battery).
When starting from another machine, do not allow the two
machines to touch.
When connecting the booster cables, turn the starting switch
OFF position for both the normal machine and problem
machine. There is a hazard that the machine will move when the
power is connected.
Be sure to connect the positive (+) cable first when installing the
booster cables. Disconnect the negative (-) cable (ground side)
first when removing them.
When removing the booster cables, be careful not to let the
booster cable clips touch each other or to let the clips touch the
machine.
Always wear safety glasses and rubber gloves when starting the
engine with booster cables.
When connecting a normal machine to a problem machine with
booster cables, always use a normal machine with the same
battery voltage as the problem machine.
For details of the starting procedure when using booster cables,
see "Starting Engine with Booster Cables (PAGE 3-151)" in the
OPERATION section.

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SAFETY SAFETY MACHINE OPERATION

TOWING

SAFETY RULES FOR TOWING

Serious injury or death could result if a disabled machine is towed incorrectly or if there is a mistake in the selection
or inspection of the wire rope.
For towing, see "TOWING THE MACHINE (PAGE 3-147)".
Always check that the wire rope used for towing has ample strength for the weight of the machine being towed.
Never use a wire rope which has cut strands (A), reduced
diameter (B), or kinks (C). There is danger that the rope may
break during the towing operation.

Always wear leather gloves when handling wire rope.

Never tow a machine on a slope.
During the towing operation, never stand between the towing machine and the machine being towed.
Operate the machine slowly and be careful not to apply any sudden load to the wire rope.

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SAFETY MACHINE OPERATION SAFETY

LIFTING OBJECTS WITH BUCKET

SAFETY RULES FOR LIFTING OBJECTS

Do not carry out lifting work on slopes, soft ground, or other places where the machine is not stable.
Use wire rope that conforms to the specified standard.
Always observe the specified lifting load strictly.
It is dangerous if the load hits any worker or structure. Always check carefully that the surrounding area is safe
before swinging or turning the machine.
Do not start, swing, or stop the machine suddenly. There is a hazard that the lifted load will swing.
Do not pull the load to the side or in towards the machine.
Do not leave the operator's seat when there is a raised load.

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SAFETY SAFETY MAINTENANCE INFORMATION

SAFETY MAINTENANCE INFORMATION

WARNING TAG
Always attach the "DO NOT OPERATE" warning tag to the work
equipment control lever in the operator's cab to alert others that
you are performing service or maintenance on the machine.
Attach additional warning tags around the machine if necessary.
Warning tag Part No. 09963-A1640
Keep this warning tag in the tool box while it is not used. If there
is not the tool box, keep the tag in the operation manual pocket.
If any other person starts the engine, or touches or operates the
control levers or control pedals while you are performing service
or maintenance, you may suffer serious injury.

KEEP WORK PLACE CLEAN AND TIDY

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 and tidy to enable you to carry out operations safely.
If the work place is not kept claen and tidy, there is the danger that you will trip, slip, or fall over and injure yourself.
When cleaning the ceiling window which is made of organic glass (polycarbonate), use tap water and avoid use
of organic solvents for cleaning. An organic solvent like benzene, toluene or methanol can invite a chemical
reaction like dissolution and decomposition on the window glass, deteriorating polycarbonate in use.

APPOINT LEADER WHEN WORKING WITH OTHERS

When repairing the machine or when removing and installing the work equipment, appoint a leader and follow his
instructions during the operation.

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SAFETY MAINTENANCE INFORMATION SAFETY

STOP ENGINE BEFORE CARRYING OUT MAINTENANCE

Stop the machine on firm, level ground.
Select a place where there is no hazard of falling rocks or
landslides, or of flooding if the land is low.
Lower the work equipment completely to the ground and stop
the engine.
Turn the starting switch to the ON position. Operate the work
equipment control lever back and forth, left and right at the full
stroke 2 to 3 times to eliminate the remaining internal pressure
in the hydraulic circuit, and then push up lock lever (1) to the
LOCK position (L).
Check that the battery relay is off and main power is not
conducted. (Wait for approx. one minute after turning off the
engine starting switch key and press the horn switch. If the horn
does not sound, it is not activated.)

Put blocks under the track to prevent the machine from moving.

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SAFETY SAFETY MAINTENANCE INFORMATION

TWO WORKERS FOR MAINTENANCE WHEN ENGINE IS RUNNING

To prevent injury, do not carry out maintenance with the engine running. If maintenance must be carried out with
the engine running, carry out the operation with at least two workers and do as follows.
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.
When carrying out operations near the fan, fan belt, or other
rotating parts, there is a hazard of being caught in the parts, so
be careful not to come close.
Never drop or insert tools or other objects into the fan or fan belt.
Parts may break or be sent flying.

Set lock lever (1) to the LOCK position (L) to prevent the work
equipment from moving.
Do not touch any control levers or control pedals. If any control
levers or control pedals must be operated, always give a signal
to the other workers to warn them to move to a safe place.

PROPER TOOLS
Use only tools suited to the task and be sure to use the tools
correctly. Using damaged, low quality, faulty, makeshift tools or
improper use of the tools could cause serious personal injury.

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SAFETY MAINTENANCE INFORMATION SAFETY

ACCUMULATOR, GAS SPRING

The accumulator and gas springs is charged with high-pressure
nitrogen gas. When handling the accumulator, careless procedure
may cause an explosion which could lead to serious injury or
property damage. For this reason, always observe the following
precautions.
Do not disassemble the accumulator.
Do not bring it near flame or dispose of it in fire.
Do not make holes in it, weld it, or use a cutting torch.
Do not hit or roll the accumulator, or subject it to any impact.
When disposing of the accumulator, the gas must be released.
Please contact your Komatsu distributor to have this work
performed.

PERSONNEL
Only authorized personnel can service and repair the machine. Do not allow unauthorized personnel into the area.
If necessary, employ an observer.

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

WORK UNDER THE MACHINE

If it is necessary to go under the work equipment or the machine
to carry out service and maintenance, support the work
equipment and machine securely with blocks and stands strong
enough to support the weight of the work equipment and
machine.
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 control levers is
touched by accident, or there is damage occurring to the
hydraulic piping, the work equipment or the machine will
suddenly drop. This is extremely dangerous. Never work under
the work equipment or the machine.

NOISE
When carrying out 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 from the machine is too loud, it may cause temporary or permanent hearing problems.

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SAFETY SAFETY MAINTENANCE INFORMATION

WHEN USING HAMMER

When using a hammer, pins may fly out or metal particles may be
scattered. This may lead to serious injury. Always do as follows.
If hard metal parts such as pins, bucket teeth, cutting edges, or
bearings are hit with a hammer, there is a hazard that pieces
might be scattered and cause injury. Always wear safety
glasses and gloves.
When hitting pins or bucket teeth, there is a hazard that broken
pieces might be sent flying and injure people in the surrounding
area. Always check that there is no one in the surrounding area.
There is a hazard that the pin hit with strong force may fly out
and injure people in the surrounding area.

WELDING WORKS
Welding operations must always be carried out by a qualified welder and in a place equipped with proper equipment.
There is a hazard of gas, fire, or electrocution when carrying out welding, so never allow any unqualified personnel
to carry out welding.

REMOVING BATTERY TERMINALS

When repairing or welding the electrical system, wait for approx. one minute after turning off the engine starting
switch key, and then disconnect the negative (-) terminal of the battery to stop the flow of electricity.

SAFETY FIRST WHEN USING HIGH-PRESSURE GREASE TO ADJUST TRACK TENSION

Grease is pumped into the track tension adjustment system
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 property damage.
When loosening grease drain plug (1) to loosen the track
tension, never loosen it more than one 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 SPRINGS

Never attempt to disassemble the recoils spring assembly. It contains a spring under high pressure which serves
as a shock absorber for the idler. If it is disassembled by mistake, the spring will fly out and cause serious injury.
When it becomes necessary to disassemble it, ask your Komatsu distributor to do the work.

2 - 37
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SAFETY MAINTENANCE INFORMATION SAFETY

SAFETY RULES FOR HIGH-PRESSURE OIL

The hydraulic system is always under internal pressure. When inspecting or replacing piping or hoses, always
check that the pressure in the hydraulic circuit has been released. If the circuit is still under pressure, it will lead to
serious injury, so always do as follows.
For details of the method of releasing the pressure, see "METHOD FOR RELEASING INTERNAL PRESSURE
IN HYDRAULIC CIRCUIT (PAGE 4-42)". If the circuit is still under pressure, do not carry out any inspection or
replacement operation.
If there is any leakage from the piping or hoses, the surrounding area will be wet, so check for cracks in the piping
and hoses and for swelling in the hoses.
When carry out inspection, wear safety glasses and leather gloves.
There is a hazard that high-pressure oil leaking from small holes
may penetrate your skin or cause blindness if it contacts your
eyes directly. If you are hit by a jet of high-pressure oil and suffer
injury to your skin or eyes, wash the place with clean water, and
consult a doctor immediately for medical attention.

SAFETY HANDLING HIGH-PRESSURE HOSES

If oil or fuel leaks from high-pressure hoses, it may cause fire or defective operation, which may lead to serious
injury. If any loose bolts are found, stop work and tighten to the specified torque. If any damaged hoses are found,
stop operations immediately and contact your Komatsu distributor.
Replace the hose if any of the following problems are found.
Damaged or leaking hydraulic fitting.
Frayed or cut covering or exposed reinforcement wire layer.
Covering swollen in places.
Twisted or crushed movable portion.
Foreign material embedded in covering.

WASTE MATERIALS
To prevent pollution, pay careful attention to the method of disposing of waste materials.
Always put oil drained from your machine in containers. Never
drain oil directly onto the ground or dump into the sewage
system, rivers, the sea, or lakes.
Obey appropriate laws and regulations when disposing of
harmful objects such as oil, fuel, coolant, solvent, filters, and
batteries.

AIR CONDITIONER MAINTENANCE

If air conditioner refrigerant gets into your eyes, it may cause blindness; if it touches your skin, it may cause frostbite.
Never touch refrigerant.

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SAFETY SAFETY MAINTENANCE INFORMATION

COMPRESSED AIR
When carrying out cleaning with compressed air, there is a hazard of serious injury caused by flying particles.
When using compressed air to clean elements or the radiator, always wear safety glasses, dust mask, gloves,
and other protective equipment.

PERIODIC REPLACEMENT OF SAFETY CRITICAL PARTS

For using the machine safely for an extended period of time, replace safety-critical parts like hoses and seat belts
periodically.
Replacement of safety-critical parts: See "SAFETY CRITICAL PARTS (PAGE 4-14)".
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 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 safety-critical parts if any defect is found, even when they have not reached the time specified
interval.

2 - 39
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3-1
.

MACHINE VIEW ILLUSTRATIONS OPERATION

MACHINE VIEW ILLUSTRATIONS

OVERALL MACHINE VIEW

(1) Bucket (6) Boom cylinder

(2) Bucket cylinder (7) Sprocket
(3) Arm (8) Track frame
(4) Arm cylinder (9) Track shoe
(5) Boom (10) Idler

3-2
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OPERATION MACHINE VIEW ILLUSTRATIONS

CONTROLS AND GAUGES

AA: Screen with all lamps lighted up

BB: Screen for standard
CC: Maintenance time warning screen

3-3
.

MACHINE VIEW ILLUSTRATIONS OPERATION

(1) Car radio (26) Engine coolant temperature monitor

(2) Revolving warning lamp switch (option) (27) Engine oil pressure monitor
(3) Air conditioner control switch (28) Engine coolant temperature gauge
(4) Lock lever (29) Charge level monitor
(5) L.H. work equipment control lever (30) Radiator coolant level monitor
(6) One-touch power max. switch (31) Working mode monitor
(7) Travel pedals (32) Hydraulic oil temperature monitor
(8) Travel levers (33) Hydraulic oil temperature gauge
(9) Cigarette lighter (34) Maintenance interval moniotor
(10) Machine monitor (35) Service monitor
(11) Horn switch (36) Travel speed monitor
(12) R.H. work equipment control lever (37) Engine oil temperature monitor
(13) Ignition switch (38) Air cleaner clogging monitor
(14) Fuel control dial (39) Fuel gauge
(15) Lamp switch (40) Fuel level monitor
(16) Alarm buzzer stop switch (41) One-touch power max. monitor
(17) Swing lock switch (42) Auto-deceleration monitor
(18) Machine push-up switch (43) Display control monitor
(19) Swing holding brake release switch (44) Input control switch
(20) Emergency pump drive switch (45) Window washer switch
(21) Select switch (46) Wiper switch
(22) Working mode selector switch (47) Maintenance switch
(23) Wiper monitor (48) Travel speed selector switch
(24) Engine pre-heating monitor (49) Auto-deceleration switch
(25) Swing lock monitor

3-4
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OPERATION DETAILED CONTROLS AND GAUGES

DETAILED CONTROLS AND GAUGES

The following is an explanation of devices needed for operating the machine.
To perform suitable operations correctly and safely, it is important to completely understand methods of operating
the equipment, and the meanings of the displays.

MONITORING SYSTEM

AA: Screen with all lamps lighted up

BB: Screen for standard
CC: Maintenance time warning screen

A: Basic check monitors D: Meter display portion,pilot display

B: Caution monitors E: Monitor switches portion
C: Emergency monitors

3-5
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DETAILED CONTROLS AND GAUGES OPERATION

Basic Operation of Machine Monitor

If There Is Abnormality When Starting Engine

If there is any abnormality when starting the engine, the check before starting screen DD changes to the
maintenance interval warning screen CC, warning screen FF, or error screen EE.
After displaying the check before starting screen DD for 2 seconds, the screen changes to the maintenance
interval warning screen CC.
After displaying the maintenance interval warning screen CC for 30 seconds, the screen returns to the standard
screen BB.
After displaying the check before starting screen DD for 2 seconds, the screen changes to the warning screen
FF or error screen EE.

3-6
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OPERATION DETAILED CONTROLS AND GAUGES

If Any Abnormality Occurs During Operation

If any abnormality occurs during operation, the standard screen BB changes to warning screen FF-(1) or the error
screen EE.
After displaying warning screen FF-(1) for 2 seconds, the screen automatically changes to warning screen FF-(2).

3-7
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DETAILED CONTROLS AND GAUGES OPERATION

Basic Check Monitors

CAUTION
These monitors DO NOT ensure that the machine is in good condition. When performing checks before starting (daily checks),
do not simply rely on the monitors. Always dismount the machine and check each item directly.

Displays basic items among the check before starting items that must be checked before starting the engine. If there
is any abnormality, monitor for the location of abnormality will light up.

A(1) Radiator coolant level monitor A(3) Maintenance interval monitor

A(2) Engine oil level monitor

Radiator Coolant Level Monitor

Monitor (1) warns the operator that there has been a drop in the
radiator coolant level.
If the radiator coolant is low, the lamp lights up red, so check
coolant level in the radiator and subtank, and add coolant.

3-8
.

OPERATION DETAILED CONTROLS AND GAUGES

Engine Oil Level Monitor

Monitor (2) warns the operator that the oil level in the engine oil pan
has dropped.
If oil level in the engine oil pan is low, the lamp lights up red, so
check the oil level, and add oil.

Maintenance Interval Monitor

Monitor (3) lights up to warn the operator that the set time has
passed since maintenance was last performed.
This monitor screen goes out after 30 seconds and returns to the
standard screen.
For details of the method of checking the maintenance interval,
see "Maintenance Switch (PAGE 3-24)" in the Detailed controls
and gauges.

If it is desired to change the maintenance interval settings, have

your Komatsu distributor change the interval settings.

3-9
.

DETAILED CONTROLS AND GAUGES OPERATION

Caution Monitors
CAUTION
If the warning monitor lights up red, stop operations as soon as possible and perform inspection and maintenance of the
applicable location. If the warning is ignored, it may lead to failure.

These are items that should be observed while the engine is running. If any abnormality occurs, the screen displays
the item that needs immediate action.
If there is an abnormality, the monitor for the abnormal location lights up red.

B(1) Charge level monitor B(4) Engine coolant temperature monitor

B(2) Fuel level monitor B(5) Hydraulic oil temperature monitor
B(3) Air cleaner clogging monitor

Charge Level Monitor

Monitor (1) warns the operator of an abnormality in the charging
system while the engine is running.
If the battery is not being charged properly while the engine is
running, monitor (1) lights up red.
If monitor lights up red, check the V-belt for looseness. If any
abnormality is found, perform the necessary actions. For details,
see "OTHER TROUBLE (PAGE 3-153)".

REMARK
When the engine is started or stopped with the ignition switch at the ON position, the lamp may light, and the
buzzer and horn may sound momentarily, but this does not indicate any abnormality.

3 - 10
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OPERATION DETAILED CONTROLS AND GAUGES

Fuel Level Monitor

Monitor (2) lights up to warn the operator the fuel level in the tank
is low.
If the remaining amount of fuel goes down to 80 liters (21.14 US
gal), the light changes from green to red, so add fuel as soon as
possible.

Air Cleaner Clogging Monitor

Monitor (3) warns the operator of a clogged air cleaner.
If the monitor lights up red, stop the engine, inspect and clean the
air cleaner. For details, see "CHECK, CLEAN AND REPLACE AIR
CLEANER ELEMENT (PAGE 4-19)".

Engine Coolant Temperature Monitor

If monitor (4) lights up white in low temperatures, perform
warming-up operation. For details, see "Warming-up Operation
(PAGE 3-90)".
Continue warming-up operation until monitor (4) changes to green.

Hydraulic Oil Temperature Monitor

If monitor (5) lights up white in low temperatures, perform
warming-up operation. For details, see "Warming-up Operation
(PAGE 3-90)".
Continue warming-up operation until monitor (5) changes to green.

3 - 11
.

DETAILED CONTROLS AND GAUGES OPERATION

Emergency Monitors
CAUTION
If the monitor lights up red, stop the engine immediately or run at low idle, check applicable location, then perform necessary
actions.

These items should be observed while the engine is running. If there is a problem, the monitor for the abnormal
location lights up red and buzzer sounds, perform action immediately.

C(1) Engine coolant temperature monitor C(3) Engine oil pressure monitor
C(2) Hydraulic oil temperature monitor

Engine Coolant Temperature Monitor

Monitor (1) warns operator that the engine coolant temperature
has risen.
If engine coolant temperature becomes abnormally high, monitor
lights up red, overheat prevention system is automatically
actuated, and the engine speed goes down.
Stop operations and run engine at low idle until monitor (1)
changes to green.

3 - 12
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OPERATION DETAILED CONTROLS AND GAUGES

Hydraulic Oil Temperature Monitor

Monitor (2) warns operator that the hydraulic oil temperature has
risen.
If monitor lights up red during operations, run engine at low idle or
stop the engine and wait until the oil temperature goes down and
monitor (2) changes to green.

Engine Oil Pressure Monitor

Monitor (3) lights up red if the engine lubrication oil pressure goes
below normal level. If monitor lights up red, stop the engine
immediately, check the lubrication system and level of oil in the
engine oil pan.

REMARK
Color when the monitor lights up for basic check items, caution items, and emergency stop items are as follows.

Color when monitor lights up

Type of monitor When When At low
normal abnormal temperature
Radiator coolant level monitor OFF Red -
Engine oil level monitor OFF Red -
Maintenance interval monitor OFF Red -
Charge monitor OFF Red -
Fuel level monitor Green Red -
Air cleaner clogging monitor OFF Red -
Engine coolant temperature monitor Green Red White
Hydraulic oil temperature monitor Green Red White
Engine oil pressure monitor OFF Red -

3 - 13
.

DETAILED CONTROLS AND GAUGES OPERATION

Meter Display Portion

D(1) Engine pre-heating monitor D(7) One-touch power max. monitor

D(2) Swing lock monitor D(8) Engine coolant temperature gauge
D(3) Wiper monitor D(9) Fuel gauge
D(4) Auto-deceleration monitor D(10) Hydraulic oil temperature gauge
D(5) Working mode monitor D(11) Service meter
D(6) Travel speed monitor

Pilot Display
When starting switch is ON, the pilot display lights up when display items are functioning.

Engine Pre-heating Monitor

Monitor lamp (1) indicates pre-heating time required when starting
the engine at an ambient temperature below 0°C (32°F).
The monitor lamp lights when the starting switch is turned to the
HEAT position and flashes after 30 seconds to show pre-heating
is completed. (Monitor lamp will go off after 10 seconds.)

3 - 14
.

OPERATION DETAILED CONTROLS AND GAUGES

Swing Lock Monitor

Monitor (2) informs the operator that the swing lock is being
actuated.
Actuated: Lights up
When the swing lock switch is turned ON (ACTUATED), the
monitor lamp lights up.
This monitor flashes when the swing holding brake release switch
is turned on.

REMARK
The swing motor is equipped with a disc brake that mechanically
stops the rotation. When the swing lock monitor is lighted up, the
brake remains applied.

Wiper Monitor
Monitor (3) indicates operating ststus of the wiper.
The monitor display when wiper switch is operated, as follows.
When ON lights up: Wiper moves continuously
When INT lights up: Wiper moves intermittently
OFF: Wiper stops

Auto-deceleration Monitor
Monitor (4) shows if the auto-deceleration is being actuated.
The monitor display when auto-deceleration switch is operated, as
follows.
Auto-deceleration monitor ON: Auto-deceleration actuated
Auto-deceleration monitor OFF: Auto-deceleration canceled

Working Mode Monitor

Monitor (5) displays the set working mode.
The monitor display when the working mode switch is operated is
as follows.
A: A mode (for heavy-load operations)
E: E mode (for operations with emphasis on fuel economy)
L: L mode (for fine-control operations)
B: B mode (for breaker operations)

3 - 15
.

DETAILED CONTROLS AND GAUGES OPERATION

Travel Speed Monitor

Monitor (6) displays set mode for the travel speed.
The monitor display when the travel speed selector switch is
operated is as follows.
Lo: Low speed
Mi: Medium speed
Hi: High speed

One-Touch Power Max. Monitor

Meter (7) shows if the power max function is being actuated.
The monitor display when the knob switch on the left control lever
is operated is as follows.

Monitor lights up: Digging power is increased while knob switch is

kept pressed.

REMARK
The digging power is increased while the knob switch is being
pressed only for working modes A and E. Note that even if the
knob switch is kept pressed, the increase in power ends after
8.5 seconds.
When the knob switch is pressed, the mode is displayed in the
central portion of display GG, and after 2 seconds the monitor
in the center goes out and the screen switches to monitor
display BB.

Monitor goes out: Power max function stopped

3 - 16
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OPERATION DETAILED CONTROLS AND GAUGES

Gauges and Meter

Engine Coolant Temperature Gauge

Gauge (8) indicates the engine coolant temperature.
During normal operations, indicator should be in the black range
(A) - (C). If indicator enters the red range (A) - (B) during
operations, the overheat prevention system is actuated.

REMARK
(A) - (B): Displays red range
(A) - (C): Displays black range

The overheat prevention system acts as follows.

Red range position (A): Engine coolant temperature monitor lamp (1) lights up red.
Red range position (B): Engine speed is reduced to low idle, engine coolant temperature monitor lamp (1) lights up
red, and the alarm buzzer sounds at the same time.
The overheat prevention system remains actuated until the indicator returns to the black range.
When the engine is started, if the indicator is at position (C), engine coolant temperature monitor (1) lights up white.
In this case, carry out the warming-up operation. For details, see "Warming-up Operation (PAGE 3-90)".

Fuel Gauge
Gauge (9) indicates the amount of fuel in the fuel tank.
During operations, the indicator should be in the black range.
If indicator enters red range (A) during operations, there is less
than 110 liters (29.06 US gal) of fuel remaining in the tank, check
and add fuel.

REMARK
(A) - (B): Displays red range
(A) - (C): Displays black range

REMARK
When the remaining fuel goes below 80 liters (21.14 US gal), fuel level monitor (1) lights up red.

The correct fuel level may not be displayed for a short time when the starting switch is turned ON, but this is not an
abnormality.

3 - 17
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DETAILED CONTROLS AND GAUGES OPERATION

Hydraulic Oil Temperature Gauge

Meter (10) displays the hydraulic oil temperature.
During operations, the indicator should be in the black range.
If the indicator enters red range (A) during operations, the hydraulic
oil temperature has gone above 102°C (215.6°F).
Stop the engine or run it at low idle and wait for the hydraulic oil
temperature to go down.

REMARK
(A) - (B): Displays red range
(A) - (C): Displays black range

REMARK
Hydraulic oil temperature is as follows when the indicator enters the red range (A):
(A) position in the red range: 102°C (215.6°F) or over
(B) position in the red range: 105°C (221°F) or over
When the indicator is in the red range (A) - (B), hydraulic oil temperature monitor (1) lights up red.
If the indicator is on (C) position when starting the engine, it means that hydraulic oil temperature is 25°C (77°F) or
lower and the hydraulic oil temperature monitor (1) will be illuminated white. When this happens, refer to the section
"Warming-up Operation (PAGE 3-90)" and perform warm-up operation.

Service Meter
Monitor (11) displays the total time that the machine has been
running.
Set the periodic maintenance interval in hour. When the engine is
running, the service meter advances even if the machine is not
moving. The meter will advance by 1 for each hour of operation
regardless of the engine speed.

3 - 18
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OPERATION DETAILED CONTROLS AND GAUGES

Monitor Switches Portion

E(1) Working mode selector switches E(7) Select switch

(basic switches) E(8) Return switch
E(2) Auto-deceleration switch (selection switch) E(9) Up switch
E(3) Travel speed selector switch E(10) Down switch
E(4) Wiper switch E(11) Input confirmation switch
E(5) Window washer switch E(12) LCD monitor adjustment switch
E(6) Maintenance switch

3 - 19
.

DETAILED CONTROLS AND GAUGES OPERATION

Working Mode Selector Switch (Basic Switch)

Switch (1) is used to set the power and movement of the work
equipment.
Operations can easily be performed by selecting the mode to
match the type of operation.
A mode: For heavy-duty operations
E mode: For operations prioritizing fuel consumption
L mode: For fine-control operations
B mode: For breaker operations
GG mode: Monitor display

When the engine is started, the working mode is set automatically to A mode. When switch (1) is pressed, it is
possible to select other modes. The monitor display on display portion (GG) changes for each mode.
If it is desired to have the working mode set to start automatically in E, L, or B mode (default option setting), have
your Komatsu distributor change the setting.

REMARK
When the mode selector switch is pressed, the mode is displayed
in the center of monitor display portion (GG), and the screen
returns to standard screen (BB) after 2 seconds. (Diagram on the
right is an example of display for the E mode.)

NOTICE
When using the breaker, do not use A mode. There is danger that the breaker may be damaged.

3 - 20
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OPERATION DETAILED CONTROLS AND GAUGES

Auto-deceleration Switch (Selection Switch)

When switch (2) is pressed, the auto-deceleration is actuated, if
the control levers are in neutral position, the engine speed is
automatically lowered to reduce fuel consumption.
Monitor display portion GG ON : Auto-deceleration actuated
Monitor display portion GG OFF : Auto-deceleration canceled
Each time the switch is pressed, auto-deceleration switches
between actuated and canceled.

Auto-deceleration function
When the auto-deceleration function is ON, if the work equipment and travel levers are returned to the N position,
the engine speed will drop after 4 seconds from the operating speed to idling speed.
This makes it possible to reduce fuel consumption.
If any lever is operated when the machine is in this condition, engine speed will return to the previous operating
speed to make it possible to perform operations.

REMARK
When the auto-deceleration switch is pressed and the
auto-deceleration is actuated, the mode is displayed in the center
of display portion (GG), and the screen returns to standard screen
(BB) after 2 seconds.

3 - 21
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DETAILED CONTROLS AND GAUGES OPERATION

Travel Speed Selector Switch

WARNING
When loading or unloading from a trailer, always travel at low speed (with travel speed selector switch (3) at the Lo position).
Never operate travel speed selector switch (3) while loading or unloading.
If the travel speed is switched between Hi and Lo when the machine is traveling, the machine may deviate to one side, even
when traveling in a straight line. Stop the machine before switching the travel speed.

Switch (3) is used to set the travel speed to 3 stages.

Lo lights up : Low-speed travel
Mi lights up : Medium-speed travel
Hi lights up : Hi-speed travel
When the engine is started, the speed is automatically set to Lo.
Each time that the switch is pressed, the display changes Lo J
Mi J Hi J Lo in turn.

When traveling in high speed (Hi) or middle speed (Mi), if travel power is needed, such as when traveling on soft
ground or on slopes, the speed automatically switches to low speed (Lo), so there is no need to operate the switch.
The monitor display GG stays at Hi or Mi.

REMARK
Each time that the travel speed selector switch is operated, the
mode is displayed in the center of display portion (GG), and the
screen returns to standard screen (BB) after 2 seconds.

3 - 22
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OPERATION DETAILED CONTROLS AND GAUGES

Wiper Switch
Switch (4) operates the wiper for the front glass.
Each time the switch is pressed, it changes ON → INT → stop
(OFF).
Monitor display portion GG INT lighted up: Wiper moves
intermittently
Monitor display portion GG ON lighted up: Wiper moves
continuously
Monitor display portion GG OFF: Wiper stops

REMARK
Each time that the wiper switch is operated, the mode is displayed
in the center of display portion (GG). The screen returns to
standard screen (BB) after 2 seconds.

Window Washer Switch

Switch (5) is kept continuously pressed, window washer fluid is
sprayed onto the front glass. When the switch is released, spray
stops.

If switch (5) is kept pressed when the wiper is stopped, the

window washer fluid will spray, and at the same time, the wiper
will be actuated continuously. When switch (5) is released, the
wiper will continue to operate for 2 cycles, then stop.
If the wiper is moving intermittenly and switch (5) is kept pressed
continuously, window washer fluid will spray, and at the same
time, the wiper will be actuated continuously. When switch (5) is
released, the wiper will continue to operate for 2 cycles, then
return to intermittent operation.

3 - 23
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DETAILED CONTROLS AND GAUGES OPERATION

Maintenance Switch
Switch (6) is used to check the time remaining until
maintenance.

When switch (6) is pressed, screen on the monitor display

changes to the maintenance screen, as shown in diagram on
the right.
The time remaining until maintenance is indicated by the color of
each monitor display. After confirming the maintenance time,
perform the maintenance.
White display: More than 30 hours remaining until maintenance
Yellow display: Less than 30 hours remaining until maintenance
Red display: Maintenance time has already passed

NOTICE
1. If monitor display portion GG changes to the maintenance timing
warning screen when the engine is started or when the machine is being
operated, stop operations immediately.
2. Press switch (6) to display the maintenance screen.
Perform maintenance for any location indicated by the monitor that has
lighted red.

Maintenance display items are as follows:

Monitor Default set

Maintenance item
No. screen (H)
01 Change engine oil 500
02 Change engine oil filter 500
03 Change fuel filter 500
04 Change hydraulic oil filter 1000
05 Change hydraulic tank breather 500
Change corrosion resistor
06 1000
(option for overseas)
07 Check damper case oil level, add oil 1000
08 Change final drive case oil 2000
09 Change swing machinery case oil 1000
10 Change hydraulic oil 5000

If it is desired to change settings for the maintenance interval, have your Komatsu distributor change the settings.

3 - 24
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OPERATION DETAILED CONTROLS AND GAUGES

The method of checking time remaining until maintenance is as follows:

1. Look at the maintenance screen, press up switch (9) or down
switch (10) on the monitor switch portion, and select the item.
(Color of the monitor for selected item is inverted to black.)

2. After selecting the monitor item, press input confirmation

switch (11). Display screen will switch to the time remaining
until maintenance.
(Press back switch (8) to return to the previous screen.)

3. Check the time remaining until maintenance.

(a): Time remaining until maintenance
(b): Default setting for maintenance interval

When only checking the time remaining until maintenance,

press back switch (8) twice.
The screen will return to the normal operation monitor screen.
When canceling time remaining until maintenance and
returning to the default time setting, press inout confirmation
switch (11). The screen will switch to the default setting screen.
4. After checking the time on the default setting screen, press
input confirmation switch (11).
The screen will return to the maintenance screen.
(Press back switch (8) to return to the previous screen.)

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DETAILED CONTROLS AND GAUGES OPERATION

Select Switch
(When setting option)
This switch (7) is used as a selector switch when setting the oil flow
for each working mode (A, E, B mode).

When working mode is A or E

(1) Press select switch (7) and the normal screen on the monitor
display changes to the flow setting screen shown in the diagram
on the right.
(2) Press UP switch (9) or DOWN switch (10) to adjust the oil flow
as desired. One segment on the scale is approx. 70 liter (18.49
US gal)/min.
(3) After completing the flow setting, press input confirmation
switch (11).
The monitor display will return to the normal screen.

REMARK
The flow can be adjusted only when it is possible to install an
attachment. (if equipped)

When working mode is B mode

(1) Press select switch (7) and the normal screen on the monitor
display changes to the flow setting screen shown in the diagram
on the right.
(2) Press UP switch (9) or DOWN switch (10) to adjust the oil flow
to a suitable level.
(3) After completing the flow setting, press input confirmation
switch (11).

(4) With the operation in Step (3), the flow setting screen changes
to the fine flow adjustment screen shown in the diagram on the
right.
(5) Press UP switch (9) or DOWN switch (10) to adjust the oil flow
to a suitable level. One segment on the scale is approx. 20 liter
(5.28 US gal)/min.
(6) After completing the flow setting, press input confirmation
switch (11).
The monitor display will return to the normal screen.

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OPERATION DETAILED CONTROLS AND GAUGES

Back Switch
Press this switch (8) when in the maintenance mode,
brightness/contrast adjustment mode, or select mode. The screen
will return to the previous screen on the monitor display.

Up Switch, Down Switch

Press up switch (9) or down switch (10) when in the maintenance
mode, brightness/contrast adjustment mode, or select mode to
move the cursor on the monitor display (colors of selected monitor
are inverted) up, down, left, or right.

Input Confirmation Switch

Press this switch (11) to confirm the selected mode when in the
maintenance mode, brightness/contrast adjustment mode, or
select mode.

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DETAILED CONTROLS AND GAUGES OPERATION

Liquid Crystal Monitor Adjustment Switch

Press switch (12) to adjust the brightness or contrast of the display
monitor.

Adjusting brightness and contrast

1.When monitor adjustment switch (12) is pressed, the monitor
display screen changes to the brightness/contrast screen shown
in the diagram on the right.

Adjusting brightness
2. Use the brightness/contrast screen and press up switch (9) or
down switch (10) to select brightness of the monitor.
(The selected monitor is inverted to black.)

3.When the screen changes to the brightness adjustment screen,

press up switch (9) or down switch (10) to adjust the brightness.
4.After completing adjustment of the brightness, press input
confirmation switch (11).

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OPERATION DETAILED CONTROLS AND GAUGES

Adjusting contrast
2.Use the brightness/contrast screen and press up switch (9) or
down switch (10) to select the contrast monitor.
(The selected monitor is inverted to black.)

3.When the screen changes to the contrast adjustment screen,

press up switch (9) or down switch (10) to adjust the contrast.
4.After completing adjustment of the contrast, press input
confirmation switch (11).

REMARK
When the machine is shipped from the factory, the brightness is set
to the maximum (+) setting. The contrast is set to the midpoint
value.

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DETAILED CONTROLS AND GAUGES OPERATION

SWITCHES

(1) Starting switch (8) Horn switch

(2) Fuel control dial (9) One-touch power max. switch
(3) Cigarette lighter (10) Room lamp switch
(4) Swing lock switch (11) Emergency pump drive switch
(5) Lamp switch (12) Swing brake cancel switch
(6) Alarm buzzer switch (13) Revolving warning lamp switch
(7) Machine push-up switch (if equipped)

Starting Switch
Starting switch (1) is used to start or stop the engine.
(A): OFF position
The key can be inserted or withdrawn. Switches for the electrical
system (except room lamp), are all turned off and the engine is
stopped.
(B): ON position
Electric current flows through the charging and lamp circuits. Keep
starting switch key in the ON position while the engine is running.
(C): START position
This is the engine-start position. Keep the key at this position
during cranking. Immediately after starting the engine, release the
key. It will automatically return to the ON position (B).
(D): HEAT (pre-heat) position
When starting the engine in cold weather, turn the key to HEAT position (D), the pre-heating monitor lights up. Keep
the key at this position until the monitor lamp flashes. Immediately after the pre-heating lamp flashes, release the
key. The key automatically returns to OFF position (A). Then, start the engine by turning the key to START position
(C).

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OPERATION DETAILED CONTROLS AND GAUGES

Fuel Control Dial

This dial (2) adjusts the engine speed and output.
(a) Low idle (MIN): Turned fully to the left
(b) Full speed (MAX): Turned fully to the right
REMARK
Even if the fuel control dial is turned several notches up from low
idling position (a) or down from full speed position (b), there is a
range where the engine speed does not change, but this is not an
abnormality.

Cigarette Lighter
This switch (3) is used to light cigarettes.
To use, push the lighter in. After a few seconds it will spring back.
Pull out the lighter and light your cigarette.
By removing the cigarette lighter, the socket is available as a
power source for the yellow flashing lamp.
Max. current is 85 W (24V x 3.5 A).

Swing Lock Switch

WARNING
When not using the swing operation, e.g. when traveling, put the swing
lock switch to the OFF position.
On slopes, even when the swing lock switch is at the ON position, the
weight of the work equipment may cause the upper structure to swing
if the swing control lever is operated in the downhill direction.

Switch (4) is used to lock the upper structure so it will not swing.
(a) ON position: The swing lock is always applied, and the upper
structure will not swing even if the swing is
operated. In this condition, the swing lock lamp
lights up.
(b) OFF position: The swing lock is applied only when the swing
control lever is in the neutral position, and
released when operating the swing control lever.
The swing lock is actuated in 7 seconds after
putting the swing control lever in the neutral
position.

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DETAILED CONTROLS AND GAUGES OPERATION

Lamp Switch
Switch (5) is used to turn on the front lamps, working lamps,
additional lamps at top front of the cab, and monitor lighting.
(a) ON: Lamps light up
(b) OFF: Lamps go off

Alarm Buzzer Stop Switch

This switch (6) is used (when the engine is running) to stop the
alarm buzzer when it has sounded to warn of a problem in a
warning item.

REMARK
The switch (6) is an automatic return switch. For this reason, if the
switch is pressed to position (a) and released, it will return to STOP
position (b), but this is not a problem.

Machine Push-up Switch

This switch (7) is used to switch the safety valve set pressure at the
head end of the boom cylinder to two levels.

(a) Low-pressure setting: The boom thrust force is weak, so the

swaying of the chassis is small during
digging operations, and digging
operations can be carried out smoothly.
This is used for general digging
operations on normal ground, soft rock,
or blasted rock.
(b) High-pressure setting: The thrusting force of the boom
becomes more powerful, so it is easy to
escape from soft ground.

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OPERATION DETAILED CONTROLS AND GAUGES

Horn Switch
When the switch (8) at the tip of the right work equipment control
lever is pressed, the horn will sound.

One-Touch Power Max. Switch

This switch (9) on the left work equipment control lever is used to
actuate the power max and slow down functions.
Press once (single click) and keep the switch pressed. The
one-touch power max. function is actuated for a maximum of 8.5
seconds at A and E mode.

Room Lamp Switch

NOTICE
It is possible to turn on the interior cab room lamp even when starting
switch is in the OFF position, do not forget to turn it off.

This switch (10) is used to light up the room lamp.

(a) ON position: Lights up
(b) OFF position: Goes out
It will also light up even when the starting switch is off.

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DETAILED CONTROLS AND GAUGES OPERATION

Emergency Pump Drive Switch

NOTICE
Emergency pump drive switch is provided to make it possible to perform
work for a short time when there is a failure in the pump control system. It
is necessary to repair the abnormal location as soon as possible.

This switch (11) is used to make it possible to carry out operations

temporarily if any abnormality should occur in the pump control
system (when the display shows E02).
(a) When abnormal : Move switch up
(b) When normal : Move switch down
If the display shows E02, move the switch up to make it possible to
carry out work.

Swing Parking Brake Release Switch

NOTICE
This switch makes it possible to perform swing operations for a short even
when there is a problem in the swing parking brake electric system. DO
NOT use this switch except in emergencies. Repair the problem as soon as
possible.

This switch (12) is used to make it possible to carry out operations

temporarily if any abnormality should occur in the swing brake
system (when the display shows E03).
(a) When condition is abnormal: Move switch up
(b) When condition is normal: Move switch down
When the display is "E03", move this switch up to make it
possible to carry out operations.

Rotating Lamp Switch (If Equipped)

This switch (13) is used to light up the yellow rotating lamp on top
of the cab.
(a) ON: Lamps light up
(b) OFF: Lamps go off

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OPERATION DETAILED CONTROLS AND GAUGES

CONTROL LEVERS AND PEDALS

(1) Lock lever (3) Left work equipment control lever

(2) Travel levers (with auto-deceleration system)
(with a pedal and auto-deceleration system) (4) Right work equipment control lever
(with auto-deceleration system)

Lock Lever

WARNING
When leaving the operator's compartment, set the lock lever (1)
securely to the LOCK position (L). If the lock lever is not at the LOCK
position (L) and the control levers are touched by mistake, it may lead
to serious personal injury.
Check that the condition of the lock lever (1) is as shown in the diagram.
When pulling or pushing the lock lever (1) up, be careful not to touch the
work equipment control lever.

This lever (1) is a device to lock the work equipment, swing, travel, and attachment (if equipped) control levers.
Push the lever (1) down to apply the lock.
This lock lever is a hydraulic lock, so even if it is in the lock position (L), the work equipment control lever and travel
lever will move, but the work equipment, travel motor, and swing motor will not work.

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DETAILED CONTROLS AND GAUGES OPERATION

Travel Levers

WARNING
Do not rest your foot on the pedal during operations. If the pedal is
depressed by mistake, the machine may suddenly move and cause a
serious accident. Be extremely careful when operating the pedal for
travel or steering operations. When you are not using the pedal, do not
rest your foot on it.
If the track frame is facing the rear, the direction of travel operations will
be reversed when the travel lever is operated. (The machine will travel
forward when operated in reverse, and in reverse when operated
forward; the left and right directions will also be reversed.)
When operating the travel levers, check if the track frame is facing the
front or the rear. (If the sprocket is at the rear, the track frame is facing
the front.)

This lever (2) is used to change the direction of travel between

forward and reverse. ( ) shows the pedal operation.
(a) FORWARD: The lever is pushed forward
(The pedal is angled forward)
(b) REVERSE: The lever is pulled back
(The pedal is angled back)
N (Neutral): The machine stops

REMARK
Machines equipped with travel alarm (If equipped)
If the lever is shifted to the forward or reverse position from the neutral position, the alarm sounds to warn that the
machine is starting to move.

Work Equipment Control Lever

Left work equipment control lever (3) is used to operate the arm
and upper structure.

Arm operation
(a) Arm OUT
(b) Arm IN

Swing operation
(c) Swing to right
(d) Swing to left

N (Neutral) : The upper structure and arm are held in position and
do not move.

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OPERATION DETAILED CONTROLS AND GAUGES

Right work equipment control lever (4) is used to operate the boom
and bucket.

Boom operation
(a) RAISE
(b) LOWER

Bucket operation
(c) DUMP
(d) CURL

N (Neutral) : The boom and bucket are held in position and do not
move.

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DETAILED CONTROLS AND GAUGES OPERATION

SUN ROOF
WARNING
When leaving the operator's seat, set the lock lever securely to the LOCK
position (L).
If the lock lever (1) is in the FREE position (F) and the control lever is
touched by mistake, this may lead to a serious accident.

Opening
1. Set the lock lever (1) securely to the LOCK position (L).
2. Check for any ceiling window movement by pulling lock knob
(A) located on front side, then push up and open the ceiling
window grasping grip (B).

REMARK
When an overhead guard (if equipped) or top guard (if equipped)
is installed, the sun roof does not open.

Closing
Hold grip (B), lower the ceiling window, and apply lock (A). If the lock cannot be applied, open the ceiling window,
then pull it in again and apply the lock.

WINDSHIELD
WARNING
When opening or closing the front window, bottom window, or door,
always set the lock lever (1) in the LOCK position (L).
If the control levers are not locked and they are touched by accident,
this may lead to a serious accident.
When opening or closing the window at the front of the cab, stop the
machine on horizontal ground, lower the work equipment completely to
the ground, stop the engine, then carry out the operation.
When opening the front window, hold the grip securely with both hands,
pull up, and do not let go until the automatic lock catch is locked.
When closing the front window, the window will move quicker under its
own weight. Hold the grips securely with both hands when closing it.

It is possible to stow (pull up) the front window in the roof of the operator's compartment.

REMARK
With the single-pane front glass, the cab front window cannot be opened.

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OPERATION DETAILED CONTROLS AND GAUGES

Opening
1. Stop the machine on level ground, lower the work equipment
completely to the ground, then stop the engine.
2. Set the lock lever securely in the LOCK position (L).

3. Check that the wiper blade is stowed in the right stay.

4. Grip handles (A) at the top right and left of the front window,
and pull lock lever (B) toward yourself to release the lock at the
top of the front window. The top of the front window will come
out.

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DETAILED CONTROLS AND GAUGES OPERATION

5. Hold lower knob (C) with your left hand from inside the
operator's cab, and with your right hand, grip top knob (D), pull
it up, and push it against lock catch (E) at the rear of the cab
securely to lock the window.

6. Check that lock lever (B) is securely in the LOCK position.

The lock is engaged if the arrow on lock case (F) matches
the position of the arrow on lock lever (B). Check visually.
If the arrow on lock case (F) does not match the position of
the arrow on lock lever (B), the lock is not engaged. Repeat
the operation in Step 5 to engage the lock.

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OPERATION DETAILED CONTROLS AND GAUGES

Closing

WARNING
When closing the window, lower it slowly and be careful not to get your hand caught.

1. Stop the machine on level ground, lower the work equipment completely to the ground, then stop the engine.
2. Set the lock lever securely in the LOCK position (L).

3. Grip left and right handles (A), and pull down lock lever (B) to
release the lock.

4. Grip handle (C) at the bottom of the front window with your left
hand and handle (D) at the top with your right hand, push to the
front, then lower slowly.

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DETAILED CONTROLS AND GAUGES OPERATION

5. When the bottom of the window reaches the top of the bottom
window, push the top of the window to the front to push it
against left and right lock catches (G) and engage the lock.

6. Check that lock lever (B) is securely in the LOCK position.

The lock is engaged if the arrow on lock case (F) matches
the position of the arrow on lock lever (B). Check visually.
If the arrow on lock case (F) does not match the position of
the arrow on lock lever (B), the lock is not engaged. Repeat
the operation in Step 5 to engage the lock.

Removing Lower Windshield

1. Open the front window, then hold grip (A), pull up, and remove
the bottom window.

2. After removing the bottom window, store it at the rear of the

operator's cab and lock it securely with left and right locks (B).
When removing, always hold the glass with one hand and
release the lock with the other hand.

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OPERATION DETAILED CONTROLS AND GAUGES

EMERGENCY EXIT FROM OPERATOR'S CAB

If for some reason, the cab door does not open, remove the rear
window and use it as an emergency escape.
Remove the rear window as follows.
1. Pull ring (1) and completely remove seal (2) from the rubber
core.

2. With pressure push on corner of the window, the glass will fall outside.
Do not remove the rear window except when using it as an emergency exit.

DOOR LOCK
WARNING
Before the releasing the door lock, always stop the machine on flat ground.
Never release the door lock on a slope. The door may suddenly close and cause injury.
When releasing the door lock, do not extend your body or hands outside the machine and do not put your hands on the door
frame. The door may suddenly close and cause injury.

Use the door lock to fix the door in position after opening it.
1. Push the door against catch (1) to lock it in position.
2. When closing the door, push down the lever (2) on the left of
the operator's seat to release the catch.
3. When attaching the door in position, lock it firmly to the catch.

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DETAILED CONTROLS AND GAUGES OPERATION

CAP WITH LOCK

Use the starting switch key to open and close the locks on the caps and covers.
For details of the locations of the caps and covers with locks, see "LOCKING (PAGE 3-124)".
Insert the key as far as it will go to the shoulder (A). If the key is
turned before it is inserted all the way, it may break.

Opening and Closing Caps with Lock

Type A is used for the fuel tank cap; type B is used for the hydraulic tank cap.

Opening the Cap

1. Insert the key into the key slot.
2. Turn the key clockwise (counterclockwise for type B), align the
key groove with counter mark (3) on the cap, then open the
cap.
(1): Open
(2): Lock

Locking the Cap

1. Turn the cap until tight, then insert the key into the key slot.
2. Turn the starting switch key counterclockwise (clockwise for the B type) and remove the key.

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OPERATION DETAILED CONTROLS AND GAUGES

Opening and Closing Cover with Lock

Opening the Cover (Locked Cover)

1. Insert the key into the key slot.
2. Turn the key counterclockwise and open the cover by pulling
the cover grip.
(A): Open
(B): Lock

Locking the Cover

1. Close the cover and insert the key into the key slot.
2. Turn the key clockwise and take the key out.

HOT AND COOL BOX

This is on the right side at the rear of the operator's seat. It is
interconnected with the air conditioner: it stays warm when the
heating is used, and stays cool when the cooling is used.

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DETAILED CONTROLS AND GAUGES OPERATION

MAGAZINE BOX
(The cup holder is provided separately at the front of the magazine box.)
Located on left side of the operator's seat.
Keep the Operation and Maintenance Manual in this box so that it
can be taken out and read whenever necessary.

ASHTRAY
This is under the machine monitor at the front right of the operator's
compartment.
Always make sure that you extinguish your cigarette, then put it in
the ashtray and close the lid.

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OPERATION DETAILED CONTROLS AND GAUGES

AIR CONDITIONER CONTROLS

Air Conditioner Control Panel

(1) OFF switch (6) FRESH/RECIRC selector switch

(2) Fan switch (7) Display monitor
(3) Temperature control switch (8) Air conditioner switch
(4) Vent selector switch (9) Sunlight sensor
(5) Auto switch

OFF Switch
Switch (1) is used to stop the fan and air conditioner.
When OFF switch (1) is pressed, the set temperature and air
flow display on display monitor (7), the lamps above auto switch
(5), and air conditioner (8) go out, and operation stops.

REMARK
When switch (1) is turned to the OFF position, the lamp above
FRESH/RECIRC selector switch (6) does not go out, but this is not
a problem.

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DETAILED CONTROLS AND GAUGES OPERATION

Fan Switch
Switch (2) is used to adjust the air flow.
The air flow can be adjusted to six levels.
Press the ∧ switch to increase the air flow; press the ∨ switch to
reduce the air flow.
During auto operation, the air flow is automatically adjusted.

A: Liquid crystal dispiay

B: Air flow
a: Air flow "low"
b: Air flow "medium 1"
c: Air flow "medium 2"
d: Air flow "medium 3"
e: Air flow "medium 4"
f: Air flow "high"

Temperature Control Switch

Switch (3) is used to control temperature inside the cab. The
temperature can be set between 18°C (64.4°F) and 32°C (89.6°
F).
Press the ∧ switch to raise the set temperature; press the ∨ s
witch to lower the set temperature.
The temperature is generally set at 25°C (77°F).
The temperature can be set in stages of 0.5°C (0.9°F).

<Monitor display and the function>

Monitor display (°C) Set temperature

18.0 Max. cooling
Adjusts temperature inside cab to set
18.5 to 31.5
temperature
32.0 Max. heating

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OPERATION DETAILED CONTROLS AND GAUGES

REMARK
If the mode is set to auto mode and the temperature setting is set to 18.0 °C (64.4 °F) or 32.0 °C (89.6 °F), the air
flow from the fan is always set to HIGH and does not change even when the set temperature is reached.

Vent Selector Switch

Switch (4) is used to select the vents.
When switch (4) is pressed, the display on monitor display (7)
switches and air blows out from the vents displayed.
During automatic operation, the vents are automatically
selected.

(A): Rear vent (4 places)

(B1): Face vent (1 place)
(C): Foot vent (1 place)
(D): Front window glass vent (2 place)
(B2): Front window glass vent (1 place)

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DETAILED CONTROLS AND GAUGES OPERATION

Auto Switch
With switch (5), the air flow, vents, and air source
(RECIRC/FRESH) are automatically selected according to the set
temperature.
When auto switch (5) is pressed, the lamp above the auto switch
lights up.
Press switch (5), then use temperature control switch (3) to set
the temperature, and run the air conditioner under automatic
control.
When the control is switched from automatic operation to
manual operation, it is possible to operate the to change air flow,
vents, and air source (RECIRC/FRESH). When manual control
is used, lamp above the auto switch goes out.

REMARK
When Auto Mode is selected, if the set temperature is set to 18.0 °C (64.4 °F) or 32.0 °C (89.6 °F), the air flow is
always set to High, but this is not a problem.

FRESH/RECIRC Selector Switch

Switch (6) is used to switch the air source between recirculation of
the air inside the cab and intake of fresh air from the outside.
When switch (6) is pressed, the lamp above the selector switch
lights up to show that air is being blown out.
During automatic operation, the selection of inside air (RECIRC)
and outside air (FRESH) is performed automatically.

Outside air is shut off and only air inside the cab is circulated.
RECIRC
Use this setting to perform rapid cooling of the cab or when outside air is dirty.
Outside air is taten into the cab.
FRESH
Use this setting to take in fresh air when performing demisting.

Display Monitor
Monitor (7) displays the status of temperature setting (a), air flow
(b), and vents (c).
When OFF switch (1) is pressed, the display of temperature
setting (a) and air flow (b) goes out, and operation stops.

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OPERATION DETAILED CONTROLS AND GAUGES

Air Conditioner Switch

Switch (8) is used to turn the air conditioner (cooling,
dehumidifying, heating) ON or OFF.
When the fan is actuated (display (b) is shown) and air
conditioner switch (8) is pressed, the air conditioner is switched
ON, lamp above the air conditioner switch lights up, and the air
conditioner starts.
When switch (8) is pressed again, the air conditioner is switched
OFF, lamp above the air conditioner switch goes out, and the air
conditioner stops.
Air conditioner cannot be operated while the fan is off.

Sunlight Sensor
This sensor (9) automatically adjusts the flow of air from the vents
to match the strength of the sun's rays. In addition, it automatically
detects changes in the temperature inside the cab caused by
changes in the strength of the sun's rays beforehand and
automatically adjusts the temperature.

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DETAILED CONTROLS AND GAUGES OPERATION

Method of Operation
The air conditioner can be operated automatically or manually. Select the method of operation as desired.

Automatic Operation
1. Turn auto switch (5) ON.
The lamp above switch (5) lights up.
The set temperature (a) and air flow (b) are displayed on the
monitor.

2. Use temperature set switch (3) to set to the desired

temperature. The air flow, combination of vents, and selection
of fresh or recirculated air is automatically selected according
to the set temperature, and the air conditioner is operated
automatically to provide the set temperature.

REMARK
When vent display monitor (c) displays (d) or (e), and engine
coolant temperature is low, the air flow is automatically limited to
prevent cold air from blowing out.

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OPERATION DETAILED CONTROLS AND GAUGES

Stopping Automatic Operation

Press OFF switch (1). The displays for temperature setting (a) and
air flow (b) on monitor (7), and lamps above auto switch (5) and air
conditioner switch (8) go out, the operation stops.

Manual Operation
1. Press fan switch (2) and adjust the air flow. When doing this,
check that temperature setting (a) and air flow (b) are displayed
on monitor (7).

2. Turn air conditioner switch (8) ON. Check that the lamp above
air conditioner switch lights up.

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DETAILED CONTROLS AND GAUGES OPERATION

3. Press temperature setting switch (3) and adjust temperature

inside the cab.

4. Press vent selector switch (4) and select the desired vents.
When this is done, the display for vent (c) of the display monitor
changes according to the selection.

5. Press RECIRC/FRESH selector switch (6) and select

recirculation of the air inside the cab (RECIRC) or intake of
fresh air from outside (FRESH).

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OPERATION DETAILED CONTROLS AND GAUGES

Stopping Manual Operation

Press OFF switch (1). The displays for temperature setting (a) and
air flow (b) on monitor (7), and lamps above auto switch (5) and air
conditioner switch (8) go out, the operation stops.

Operation with Cold Air to Face and Warm Air to Feet

To operate with cold air blowing to the face and warm air blowing
to the feet, set as follows.
1. Press fan switch (2) and adjust the air flow. When doing this,
check that temperature setting (a) and air flow (b) are displayed
on monitor (7).

2. Press vent selector switch (4) and set the vent display on the
display monitor (C) to the display shown in the diagram on the
right.

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DETAILED CONTROLS AND GAUGES OPERATION

3. Turn air conditioner switch (8) ON. Check that the lamp above
air conditioner switch lights up.

4. Adjust fan switch (2), temperature setting switch (3) and

RECIRC/FRESH selector switch (6) to the desired positions.

Defroster Operation
1. Press fan switch (2) and adjust the air flow. When doing this,
check that temperature setting (a) and air flow (b) are displayed
on monitor (7).

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OPERATION DETAILED CONTROLS AND GAUGES

2. Press vent selector switch (4) and set vent display on the
display monitor to (f) or (g) as shown in diagram on the right.

3. Press RECIRC/FRESH selector switch (6) and set it to take in

fresh air.

4. Press temperature setting switch (3) and set temperature on

the display (7) monitor to maximum heating.

5. Adjust vents (A), (B1), and (B2) so that the air blows onto the
window glass.
(Vents (C) and (D) are fixed and cannot be adjusted.)

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DETAILED CONTROLS AND GAUGES OPERATION

When operating in the rainy season or when it is desired to remove

the mist from the window glass or to dehumidify the air, turn air
conditioner switch (8) ON.

Use Air Conditioner with Care

NOTICE
If water gets into the control panel or sunlight sensor, it may lead to unexpected failure. Be careful not to let water get on these
parts. In addition, never bring any flame near these parts.
For the auto function of the air conditioner to display its full effect, always keep the sunlight sensor clean and do not leave
anything around the sunlight sensor that may interfere with its sensor function.

Ventilation
If you smoke when the air conditioner is on, the smoke may start to hurt your eyes, so open the window and turn
the lever to FRESH for a while to remove the smoke while continuing the cooling.
When running the air conditioner for a long time, turn the lever to the FRESH position once an hour to carry out
ventilation and cooling.

Temperature Control
When the cooler is on, set the temperature so that it feels slightly cool when entering the cab (5 or 6 °C (9 or 10.8
°F) lower than the outside temperature). This temperature difference is considered to be the most suitable for your
health, so always be careful to adjust the temperature properly.

Inspection and maintenance of Air Conditioner Equipped Machine

When carrying out an inspection and maintenance of a machine equipped with air conditioner, see "CHECK AND
MAINTENANCE AIR CONDITIONER (PAGE 4-36), CHECK AIR CONDITIONER COMPRESSOR BELT
TENSION, ADJUST (PAGE 4-52), CLEAN AIR CONDITIONER FRESH/RECIRC FILTERS (PAGE 4-62)" and
follow the instruction on the table.

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OPERATION DETAILED CONTROLS AND GAUGES

Other Functions

Self-diagnostic Function
It is possible to perform troubleshooting of various sensors and equipment used on the air conditioner.
1. Turn the starting switch key to the ON (B) position.
2. Press OFF switch (1). The temperature setting and air flow
display on the liquid crystal display portion go out and
operation stops.
3. If the "∨" and "∧" parts of temperature setting switch (3) are
kept pressed at the same time for at least 3 seconds, the
troubleshooting mode is displayed on the liquid crystal display
portion.

<Monitor display and failure mode>

Display Failure mode

E-- No failure
E11 Disconnection in RECIRC sensor
E12 Short circuit in RECIRC sensor
E15 Disconnection in water temperature sensor
E16 Short circuit in water temperature sensor
E18 Short circuit in sunlight sensor
E43 Abnormality in vent damper
E44 Abnormality in air mix damper
E45 Abnormality in RECIRC/FRESH damper

When more than one failure is detected, press the "∨" or "∧" portion of temperature setting switch (3) to display
the failures in turn.
After completing the troubleshooting, press OFF switch (1) again to return to the normal display.

If any problem is detected by the self-diagnostic function, contact your Komatsu distributot perform inspection and
repair.

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DETAILED CONTROLS AND GAUGES OPERATION

Function to Switch Set Temperature Display Between Fahrenheit and Celsius

It is possible to switch the set temperature display between °F and
°C.
If the "∨" and "∧" portions of temperature setting switch (3) are
pressed at the same time for more than 5 seconds while the fan is
running, the temperature display will switch between °F and °C.
(Note that the unit is not displayed.)

Liquid crystal display range

°C 18.0 to 32.0
°F 63 to 91

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OPERATION DETAILED CONTROLS AND GAUGES

RADIO

Control Panel

(1) Power switch, Volume control knob, Balance (5) AS/PS button
control knob (6) Preset station buttons (1,2,3,4,5,6)
(2) SEL button (7) Display
(3) FM/AM selection button (8) Time reset button
(4) Display selection button (9) Tuning button

Power switch, Volume control knob, Balance control knob

Press this knob (1) to turn the power for the radio on. The frequency is displayed on display (7). Press the knob
again to turn the power off.
Turn the knob clockwise to increase the volume; press counterclockwise to reduce the volume. The range for the
volume is VOL 0 - VOL 40.

SEL button
Each time this button (2) is pressed, the mode changes as follows: VOL (volume) J BAS (bass) J TRE (treble) J
BAL (balance). The mode is displayed on display (7). For details of each mode, see "Method of Operating Mode
(PAGE 3-64)".

FM/AM Selection Button (AM/FM)

Press this button (3) to select the desired band.
Each time the button is pressed, the band changes FM J AM J FM . . .

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DETAILED CONTROLS AND GAUGES OPERATION

Display Selection Button (TIME)

On this machine, priority is given to the frequency display. When the frequency is being displayed, press button (4)
and the display will show the present time for 5 seconds. After 5 seconds pass, the display returns automatically
to the frequency display. If any button other than TIME ADJ (H, M, ADJ) is pressed within 5 seconds, the display
returns to the frequency display. For details of the method of adjusting the time, see "Setting Correct Time (PAGE
3-64)".

AS/PS button
This button (5) actuates the auto store and preset scan functions.
Auto store
If this button is pressed for more than 2 seconds during radio reception, a search is made automatically of the
6 station settings to find an unused preset number, and that frequency is stored in the preset memory.
Preset scan
If this button is pressed within 2 seconds, it is possible to select one of the already preset stations. Wait for 6 sec.
after pressing the button and then press the button again to select the next preset station. If it is impossible to
receive the preset frequency, the selection advances after 1 second to the next preset station.

Preset Station Buttons (1, 2, 3, 4, 5, 6)

If this button (6) has been used to decide which stations to preset, it is possible to select the desired station at a
touch. It is possible to preset 6 stations each for both AM and FM.
For details of the method of presetting the stations, see "Method of Setting with Preset Button (PAGE 3-63)".

Display
In this display (7), receiving band, frequency, preset No. and time are shown.

Time Reset Button

Use this button (8) when adjusting the time. For details of the method of adjusting the time, see "Setting Correct
Time (PAGE 3-64)".
H: Hour
M: Minute
ADJ: Sets to 00 minutes

Tuning Button (TUNING)

Use this button (9) to change the frequency.
For further details, see "Method of Tuning (PAGE 3-63)"

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OPERATION DETAILED CONTROLS AND GAUGES

Controls of Radio

Method of Setting with Preset Button

1. Press power switch (1) and display the frequency on display
(7).
2. Use tuning button (9) to set to the desired frequency. There are
two methods for tuning: auto tuning and manual tuning.
3. With the display (7) showing the desired frequency, keep the
desired Preset button No pressed for at least 1.5 seconds. The
reception sound will disappear, but when the presetting
operation (saving to memory) is completed, the sound will
appear again and the Preset No and frequency will be shown
on the display to show that the presetting operation has been
completed.
After completing the presetting, press Preset button (6) and
release it within approx. 1.5 seconds. This will make it possible
to receive the channel preset to that button. One channel each
for AM and FM can be preset to each Preset button.

REMARK
It is also possible to save to the Preset button by using the auto
store button.

Method of Tuning
1. Press power switch (1) and display the frequency on display (7).
2. Use tuning button (9) to set to the desired frequency. There are two methods for tuning: auto tuning and manual
tuning.
Manual tuning
Press tuning button (9) until the frequency is displayed on display (7).
< button: Frequency moves down
> button: Frequency moves up
When the frequency reaches the top or bottom frequency, it automatically continues as follows: Top J Bottom, or
Bottom J Top.

Auto tuning
Press tuning button (9) for at least 3 seconds. When a station is picked up, the tuning automatically stops. To
search for the next station, press the tuning button again for at least 3 seconds.
< button: Frequency moves down
> button: Frequency moves up
If this button is pressed during auto tuning, the auto tuning will be cancelled and the setting will return to the
frequency in use before the button was pressed.

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DETAILED CONTROLS AND GAUGES OPERATION

Method of Operating Mode

(BAS) Bass adjustment: When button (2) is pressed, BAS is displayed on display (7). If knob (1) is turned
clockwise within 5 seconds, the bass sound is emphasized. If the knob is turned
counterclockwise, the bass sound is reduced.
(TRE) Treble adjustment: When button (2) pressed, TRE is displayed on display (7). If knob (1) is turned
clockwise within 5 seconds, the treble sound is emphasized. If the knob is turned
counterclockwise, the treble sound is reduced.
(BAL) Balance adjustment: When button (2) is pressed, BAL is displayed on display (7). If knob (1) is turned
clockwise within 5 seconds, the sound from the right speaker is increased. If the knob
is turned counterclockwise, the sound from the left speaker is increased. When it is
set to BAL 0, the sound from the left and right speakers is balanced.

REMARK
With each mode, the display is returned automatically to its original setting after 5 seconds.

Setting Correct Time

1. Press display selector button (4) to display the time.
After 5 seconds, the display will return to the frequency display
and the time cannot be corrected. If this happens, press
display selector button (4) again.
2. Press time adjustment button (8) to select Hour or Minute.
H button: Adjusts the hour (each time the button is pressed, the
time advances by one hour)
M button: Adjusts the minute (each time the button is pressed,
the time advances by one minute)
If the H or M button is kept pressed, the time will advance
continuously until the button is released.
ADJ button: When the ADJ button is pressed, the time is reset
as follows.
When display is 00 - 05 minutes, time is returned to 00 min.
00 sec. (No change in hour)
When display is 55 - 59 minutes, time is advanced to 00 min.
00 sec. (Hour advances)
When display is 06 - 54 minutes, time cannot be reset. (Time
stays same)

Example
10:05 J 10:00
10:59 J 11:00
10:26 J 10:26

Use the H, M, and ADJ buttons to set to the correct time.

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OPERATION DETAILED CONTROLS AND GAUGES

Antenna
NOTICE
Before transporting the machine or putting it inside a building, stow the
antenna at position (A) to prevent any interference.

Use Radio with Care

To ensure safety, always keep the sound to a level where it is possible to hear outside sounds during operation.
If water gets into the speaker case or radio, it may lead to an unexpected failure, so be careful not to get water
on the equipment.
Do not wipe the scales or buttons with benzene, thinner, or any other solvent. Wipe with a soft dry cloth. Use a
cloth soaked in alcohol if the equipment is extremely dirty.
When the battery is replaced, the settings for the preset buttons are all cleared, so set them again.

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DETAILED CONTROLS AND GAUGES OPERATION

AUXILIARY ELECTRIC POWER

24V power source

NOTICE
Do not use this as the power source for 12 V equipment.
Pull out the connector plug for taking out electric power from the
rear side of the panel.
Maximum usable electric power is 85 W (24 V x 3.5 A).

12V power source

(if equipped)
This power source can be used up to a capacity of 60W (12V x 5A).

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OPERATION DETAILED CONTROLS AND GAUGES

FUSE

NOTICE
Before replacing a fuse, be sure to turn off the starting switch.

The fuses protect the electrical equipment and wiring from burning
out.
If the fuse becomes corroded, or white powder can be seen, or the
fuse is loose in the fuse holder, replace the fuse.
Replace the fuse with another of the same capacity.

Fuse Capacities and Circuit Names

No. Fuse Circuit name

(1) 10A Controller
(2) 20A Solenoid valve
(3) 10A PPC oil pressure lock solenoid
(4) 10A Window washer, Cigarette lighter
(5) 10A Horn
(6) 10A Spare fuse
(7) 10A Revolving warning lamp
(8) 10A Light relay
(9) 10A Radio, Speaker, Left knob switch
(10) 10A Spare fuse
(11) 20A Air conditioner unit
(12) 20A Monitors, Wiper monitor
(13) 20A Light, Light relay drive
(14) 10A OPT power supply (1)
OPT power supply (2), Travel alarm,
(15) 10A
12V power supply (if equipped)
(16) 10A Radio backup
(17) 10A Monitor (normal power source)
(18) 10A Starting switch
(19) 10A Room lamp
(20) 10A Spare fuse

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DETAILED CONTROLS AND GAUGES OPERATION

FUSIBLE LINK
If the starting motor does not turn when the starting switch is turned
to the START position, there is probably a disconnection in fusible
link (1) or (2). Open the battery box cover on the right side of the
chassis, then check and replace the fusible link.
(1): Fusible link for 24V power supply
(2): Fusible link for 24V permanent power supply

Fusible links (1) and (2) are wound with tape to the nearby wiring
harness. Check the wiring harness number before carrying out
inspection and replacement.

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

CONTROLLER
Controller installed.

NOTICE
Be careful not to get water, mud, or juice on the controller. This will
cause failure.
The engine controller has been given moisture prevention treatment, so
there is no problem if rain gets on it, but do not spray it with water when
washing the machine.
If any abnormality occurs in the controller, do not disassemble it
yourself. Contact your Komatsu distributor for repairs.

Engine controller
This is inside of the cover at the rear right side of the chassis.

Pump controller
This is on the right side at the rear of the operator's seat.

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OPERATION DETAILED CONTROLS AND GAUGES

TOOL BOX
This is used for keeping the tools.
This is inside of the battery box cover on the right side of the
machine.

GREASE GUN HOLDER

This is inside the door at the rear right of the machine. When not
using the grease gun, fit it in this holder.

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DETAILED CONTROLS AND GAUGES OPERATION

ACCUMULATOR
WARNING
The accumulator is charged with high-pressure nitrogen gas, improper operation may cause an explosion which could lead to
serious injury or damage. When handling the accumulator, always do as follows:
Pressure in the control circuit cannot be completely removed. When removing the hydraulic equipment, do not stand in the
direction that oil spurts out when performing the operation.
Loosen the bolts slowly.
Do not disassemble the accumulator.
Do not bring it near flame or dispose of it in fire.
Do not make holes in it or weld it.
Do not hit it, roll it, or subject it to any impact.
When disposing of the accumulator, the gas must be released. Contact your Komatsu distributor for proper disposal.

This machine is equipped with an accumulator in the control circuit. The accumulator is a device to store oil pressure
for the control circuit. Because an accumulator is installed, the control circuit can be actuated for a short time even
after the engine is stopped. As a result, if the control lever is moved in the LOWER direction, the work equipment
will go down under its own weight.
The accumulator is installed to the position shown in the diagram
on the right.

Releasing Hydraulic Pressure with Accumulator

1. Place the work equipment on the ground. Close the crusher attachment jaws, etc.
2. Stop the engine.
3. Turn the key in starting switch to the ON position.
4. Move lock lever to the free position. Move the work equipment control lever and attachment control pedal to full
strokes back and forth, right and left to release pressure in the control circuit.
5. Move the lock lever to the LOCK position. Lock the control lever and attachment control pedal.
6. Turn the key in starting switch to the OFF position.

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OPERATION MACHINE OPERATIONS AND CONTROLS

MACHINE OPERATIONS AND CONTROLS

BEFORE STARTING ENGINE

Walk-around Checks
Before starting the engine, look around and under the machine to check for loose nuts and bolts, or leakage of oil,
fuel, or coolant, and check condition of the work equipment and hydraulic system. Also check for loose wiring and
play, and accumulation of dust at places with high temperatures.

WARNING
Remove any flammable materials from around the battery, engine, muffler, turbocharger, or other high temperature engine parts.
Leakage of fuel or oil will cause the machine to catch fire. Check carefully, be sure to repair any problem, or contact your Komatsu
distributor.

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, hoses
Check for cracks, excessive wear, play in wotk equipment, cylinders, linkage, and hoses. If any problem is
found, repair it.

2. Remove dirt and debris from around the engine, battery, and radiator.
Check for dirt accumulated around the engine and radiator. Also check for flammable material (dry leaves, twigs,
etc.) around the battery, engine muffler, turbocharger, or other high temperature engine parts. If any dirt or
flammable materials are found, remove them.
For the method of removing dirt from the radiator, see "CLEAN AND INSPECT RADIATOR FINS, OIL COOLER
FINS, AFTERCOOLER FINS, FUEL COOLER FINS, AND AIR CONDITIONER CONDENSER FINS (only
machines equipped with air conditioner) (PAGE 4-61)".

3. Check for coolant and oil leakage around the engine

Check for oil leakage from the engine and coolant leaks from the cooling system. If any problem is found, repair
it.

4. Check for oil leakage from hydraulic equipment, hydraulic tank, hoses, and joints
Check for oil leakage. If any problem is found, repair the area where oil is leaking.

5. 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.

6. Check for problems in handrails, steps, loose bolts.

If any problem is found, repair it. Tighten any loose bolts.

7. Check for problem in gauges, monitor.

Check that there is no problem in the gauges and monitor in the operator's cab. If any problem is found, replace
the parts. Clean off any dirt on the surface.

8. Clean, check rear view mirror

Check that there is no damage to the rear view mirror. If it is damaged repair. Clean the surface of the mirror and
adjust the angle so that the area at the rear can be seen from the operator's seat.

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MACHINE OPERATIONS AND CONTROLS OPERATION

9. Seat belt and mounting clamps

Check for damage or wear to the seat belt and mounting clamps. If there is any damage, replace with new parts.

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OPERATION MACHINE OPERATIONS AND CONTROLS

Checks Before Starting

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

Check Coolant Level, Add Coolant

WARNING
Do not open the radiator cap unless necessary. Wait for the engine to cool down before checking the coolant in the sub-tank.
Immediately after the engine is stopped, the coolant is at a high temperature and the radiator is under high internal pressure.
If the cap is removed to check the coolant level in this condition, there is a hazard of burns. Wait for the temperature to go
down, then turn the cap slowly to release the pressure before removing it.

1. Open the right rear cover on the machine and check that the
cooling water level is between the FULL and LOW marks on
radiator sub tank (1) (shown in the diagram on the right).
If the water level is low, add water through the water filler of sub
tank (1) to the FULL level.
2. After adding coolant, tighten the cap securely.
3. If the sub-tank (1) is empty, there is probably leakage of
coolant. After inspecting, repair any problem immediately. If
there is no problem, check the coolant level in the radiator. If
the coolant level is low, add coolant to the radiator, then fill the
sub-tank (1).

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MACHINE OPERATIONS AND CONTROLS OPERATION

Check Oil Level in Engine Oil Pan, Add Oil

WARNING
Parts and oil are at high temperature immediately after the engine is stopped and may cause serious burns. Wait for the oil
temperature to go down before performing this operation.

1. Open the engine hood.

2. Remove dipstick (G), and wipe the oil off with a cloth.
3. Fully insert dipstick (G) into filler pipe (F), then remove it.

4. The oil level should be between the H and L marks on dipstick

(G).
If the oil level is below the L mark, add oil through oil filler (F).

5. If the oil is above the H mark, drain the excessive engine oil
from drain plug (P) at the bottom of the engine oil pan, then
check the oil level again.
Remove inspection cover (1), then operate drain valve (P) from
the inspection window.

6. If oil level is correct, securely tighten the oil filler cap and close the engine hood.

REMARK
When checking the oil level after the engine has been operated, wait for at least 15 minutes after stopping the engine
before checking.
If the machine is at an angle, make it horizontal before checking.

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OPERATION MACHINE OPERATIONS AND CONTROLS

Check Fuel Level, Add Fuel

WARNING
When adding fuel, never let the fuel overflow. This may cause a fire. If any fuel is spilled, wipe it up completely. Never bring flames
near fuel because it is highly flammable and dangerous.

1. Unscrew fuel filler cap (F) on the fuel tank.

2. When fuel filler cap (F) is opened, float gauge (G) comes up in
proportion to the remaining fuel level in the tank.
Check that the fuel tank is full.
Inspect the fuel level both visually and with float gauge (G).

3. If the fuel tank is not full, supply fuel through the fuel filler until
float gauge (G) rises to the maximum position.
(a: Approx. 50 mm (2 in))

Fuel tank capacity: 650 liters (171.73 US gal)

4. When refueling is finished, push float gauge (G) straight down

along the fuel filler cap (F), then tighten fuel filler cap (F)
securely , taking care so that float guage (G) will not get caught
on claw (2) of the cap.

REMARK
If breather hole (1) in the cap is clogged, the pressure inside the
tank will go down and no fuel will be supplied, so clean the breather
hole periodically.
The diagram on the right shows the rear surface of the cap.

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MACHINE OPERATIONS AND CONTROLS OPERATION

Check for Water and Sediment in Water Separator, Drain Water

(Machines equipped with additional fuel filter cartridge)

1. Open the engine hood.

The water separator is at the bottom and forms one unit with
the additional fuel filter.

2. It is possible to judge the water level and amount of sediment

by looking through transparent cap (2). If there is any water or
sediment collected at the bottom, set a container to catch the
drain water under drain hose (3).
3. Loosen plug (1) and drain the water.
4. When fuel comes out from drain hose (3), tighten plug (1)
immediately.
Tightening torque: 0.2 to 0.45 N·m (0.02 to 0.046 kgf·m, 0.1 to
0.3 lbft)

Drain Water And Sediment from Fuel Tank

1. Prepare a container to catch the fuel that is drained.
2. Open valve (1) at the bottom of the tank and drain the sediment
and water that has accumulated at the bottom together with
fuel. When doing this, be careful not to get fuel on yourself.
3. When only clean fuel comes out, close drain valve (1).

NOTICE
Never use trichlene for washing the inside of the tank. Use diesel fuel
only.

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OPERATION MACHINE OPERATIONS AND CONTROLS

Check Oil Level in Hydraulic Tank, Add Oil

WARNING
The parts and oil are at high temperature immediately after the engine is stopped, and may cause burns. Wait for the
temperature to go down before starting the work.
When removing the oil filler cap, turn it slowly to release the internal pressure, then remove it.

1. Set the work equipment in the posture shown in the diagram on

the right, then check the oil level and add oil if necessary.
2. If the work equipment is not in the condition shown in the
diagram on the right, start the engine, run the engine at low
speed, retract the arm and bucket cylinder rods fully, then
lower the boom, set the bucket teeth in contact with the ground,
and stop the engine.
3. Within 15 seconds after stopping the engine, move each
control lever (for work equipment and travel) to the full stroke
in all directions to release the internal pressure.
4. Check sight gauge (G). The oil level should be between the H
and L marks.

NOTICE
Do not add oil above the H line. This will damage the hydraulic circuit or
cause the oil to spurt out. If oil has been added to above the H level, stop
the engine and wait for the hydraulic oil to cool down, then drain the excess
oil from drain plug (P).

5. If the level is below the L mark, add oil through oil filler (F) at the
top of the hydraulic tank.
REMARK
The oil level will vary depending upon the oil temperature.
Accordingly, use the following as a guide:
Before starting operation: Between H and L levels
(Oil temperature 10 to 30°C (50 to 86°F))
Normal operation: Around H level
(Oil temperature 50 to 80°C (122 to 176°F))

Check Working Lamp Switch

Turn the lamp switch to the ON position and check that the
working lamp light up.

If the lamps do not light up, there is probably a broken bulb or

disconnection in the wiring, contact your Komatsu distributor for
repairs.

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MACHINE OPERATIONS AND CONTROLS OPERATION

Check Electric Wiring

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 and make the repair.
Keep the top surface of the battery clean and check the breather hole in the battery cap. If it is clogged with dirt or dust, wash
the battery cap to clear the breather hole.

Check that there is no damage to the fuses; that fuses of the specified capacity are used; that there is no
disconnection or trace of short-circuiting in the electric wiring and no damage to the covering. Check also that there
is no loosened terminals. If any, tighten them.
Moreover, pay particular attention to the electric wiring when checking the battery, engine starting motor and
alternator.
Be sure to check that there is no inflammable material accumulated around the battery. If any is found, remove
immediately.

Check Function of Horn

1. Turn the starting switch to the ON position.
2. Confirm that the horn sounds immediately when the horn button is pressed.
If the horn does not sound, contact your Komatsu distributor for repair.

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OPERATION MACHINE OPERATIONS AND CONTROLS

Adjustment

Seat Adjustment

WARNING
When adjusting the position of the operator's seat, always set the lock lever to the LOCK position to prevent any accidental
contact with the control levers.

Always adjust the operator's seat before starting each operation or when the operators change shift.
Adjust the operator's seat so control levers and switches can be operated freely and easily with the operator's
back against the backrest.

(A) Fore-and-aft adjustment

Pull lever (1) up, set the seat to the desired position, then release
the lever.
Fore-and-aft adjustment: 160 mm (6.3 in) (16 stages)

(B) Adjusting reclining

REMARK
The seat can be reclined more when the seat is pushed to the front.
The amount of reclining decreases as the seat is pushed back, so
when moving the seat back, return the seatback to the upright
position.

Pull up lever (2) and set the backrest to a position that is

comfortable for operation, then release the lever.
Sit with your back against the seat backrest when adjusting. If your
back is not against the backrest, the backrest may suddenly move
forward.

(C) Adjusting seat tilt

Forward tilt
Push lever (3) down to adjust angle of the front of seat. (4 stages)
To raise the angle at front of the seat, keep the lever pushed down and apply your weight to the rear of seat.
To lower the angle at front of the seat, keep the lever pushed down and apply your weight to the front of seat.

Rear tilt
Pull lever (4) up to adjust angle of the rear of seat. (4 stages)
To raise the angle at rear of the seat, keep lever (3) pulled up, and stand up slightly to remove your weight from
the seat.
To lower the angle at rear of the seat, keep lever (3) pulled up, and apply your weight to the seat.
Amount of tilt: Up 13°, down 13°

Adjusting seat height

It is possible to move the seat up or down by combining adjustments forward tilt and rear tilt.
After setting the forward tilt or rear tilt to the desired height, operate the opposite part to set the seat horizontal then
secure in position.
Height adjustment: 60 mm (2.4 in)

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MACHINE OPERATIONS AND CONTROLS OPERATION

(D) Adjusting armrest angle

Armrest (5) can be made to spring up by hand approx. 90°.
In addition, by turning the bottom (6) of the armrest by hand it is possible to make fine vertical adjustments of the
armrest angle.
Armrest adjustment angle: 25°.

REMARK
If the seat back is tipped to the front without raising the armrest(5), armrest will rise automatically.
If the cable at the rear of armrest (5) is tense (when the seat back is tipped to the front), armrest (5) cannot be
adjusted by turning dial (6). When adjusting the angle of armrest (5), set the seat back to a position where it is
easy to carry out operations, then adjust the armrest.

(E) Overall fore-and-aft adjustment of seat

Move lever (7) to right, set to the desired position, then release the lever. In this case, the operator's seat, left and
right control levers, and lock lever all slide together.
Fore-and-aft adjustment:180 mm (7.1 in) (9 stages)

(F) Adjusting suspension

Turn knob (8) to the right to make the suspension harder,or to the left to make the suspension softer. Adjust the
reading of the dial to match the operator's weight and select the optimum suspension.

REMARK
To obtain the optimum adjustment, turn the knob (8) so that the indicator of the weight display (kg) in the transparent
portion of knob (8) is the same as the operator's weight.

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OPERATION MACHINE OPERATIONS AND CONTROLS

Rearview Mirrors
Loosen nuts (1), screw (2) and bolt (3) of the mirror and adjust the
mirror to give the best view of the blind spots behind the operator's
cab on the left and right rear sides.
A: Mirror on right side of machine
B: Mirror on left side of machine
Adjust the mirror mount so that it is possible to see people (or
objects with a height of 1 m (3.3 ft) or a diameter of 30 cm (12 in))
at the rear left and right of the machine
Install the mirror to the dimensions listed in the table below.
Recognition areas are also shown in the table for reference.

Mounting position X : 40 mm (1.6 in)

Range of view Y (right side) : 2800 mm (9 ft 2 in)
Range of view Z (left side) : 2400 mm (7 ft 10 in)
Mirror A : Must be able to see hatched area (A)
Mirror B : Must be able to see hatched area (B)

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Seat Belt
WARNING
Before fitting the seat belt, check that there is no problem in the belt mount bracket or mounting belt. If it is worn or damaged,
replace the seat belt.
Even if no problem can be seen in the belt, replace the seat belt every 3 years. The date of manufacture of the belt is shown on
the back of the belt.
Always wear the seat belt during operations.
Fit the seat belt so that it is not twisted.

Fastening and Removing

This seat belt has a wind-in device, so it is not necessary to adjust the length.

Fastening Seat Belt

Hold grip (2) and pull the belt out from wind-in device (1), check that
the belt is not twisted, then insert tongue (3) into buckle (4)
securely.
When doing this, pull the belt lightly to check that it is properly
locked.

Removing Belt
Press button (5) in buckle (4), and remove tongue (3) from buckle (4).
The belt is automatically wound in, hold grip (2) and return the belt slowly to wind-in device (1).

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Operations Before Starting Engine

WARNING
When starting the engine, check that the lock lever is securely at the LOCK
position (L).
If the control levers are not locked and they are touched by accident when
starting the engine, the work equipment may move unexpectedly, and this
may lead to a serious accident.

1. Check that lock lever (1) is at the LOCK position (L).

2. Check the position of each lever.

Set control lever to the neutral position.

3. Insert the key in starting switch (2), turn the key to the ON
position (B), then carry out the following checks.

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If a password has been set, the input display screen is shown on

the monitor screen.
After inputting the password, press input confirmation switch (3).

REMARK
For details of the method of setting, changing, or canceling the
password, see separate "PROCEDURE FOR SETTING,
CHANGING, OR CANCELING PASSWORD".

1) The buzzer sounds for approx. 1 second, and the following

monitors and meters light up for approx. 3 seconds.
Radiator coolant level monitor (4)
Engine oil level monitor (5)
Charge level monitor (6)
Fuel level monitor (7)
Engine coolant temperature monitor (8)
Engine oil pressure monitor (9)
Engine coolant temperature gauge (10)
Fuel gauge (11)
Air cleaner clogging monitor (12)
If the monitors do not light up or the buzzer does not sound,
there is probably a failure in the monitor, so contact your
Komatsu distributor for repairs.
2) After approx. 3 seconds, the screen switches to the
working mode/travel speed display monitor. Then it
switches to the normal screen.
Fuel level monitor (7)
Engine coolant temperature monitor (8)
Engine coolant temperature gauge (10)
Fuel gauge (11)
Hydraulic oil temperature gauge (13)
Hydraulic oil temperature monitor (14)

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3) If the hydraulic oil temperature gauge goes out and caution

lamp (15) stays lighted up red, perform inspection
immediately for the item which is lighted up red.

4) If there are any items where the maintenance time has

passed, maintenance interval monitor (16) lights up for 30
seconds. Press maintenance switch (17), check the item,
then perform maintenance immediately.

For details of the method of checking the maintenance

interval, see "Maintenance Switch (PAGE 3-24)" in the
Detailed controls and gauges.

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STARTING ENGINE

Normal Starting
WARNING
Sit down in the operator's seat before starting the engine.
Do not attempt to start the engine by short-circuiting the engine starting circuit. Such an act may cause serious bodily injury
or fire.
Check that there are no persons or obstacles in the surrounding area, 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.

NOTICE
Before starting the engine, check that the fuel control dial is at the low
idle (MIN) position.
If the fuel control dial is at the FULL position, the engine will accelerate
suddenly and cause damage to the engine parts.
Do not crank the starting motor continuously for more than 20 seconds.
If the engine does not start, wait for at least 2 minutes before trying
again.

1. Check the lock lever (1) is in the LOCK position (L). If the lock
lever is in the FREE position (F), the engine does not start.

2. Set fuel control dial (2) at the low idle (MIN) position.
If it is at the high idle (MAX) position, always change it to the
low idle (MIN) position.

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3. Turn the key in starting switch (3) to the START position (C).
The engine will start.

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

5. Even after the engine is started, do not touch the work

equipment control levers and the travel pedals, while the
engine hydraulic pressure monitor lamp is still lighted.

NOTICE
If the engine oil pressure monitor does not go out even after 4 to 5 seconds
have passed, stop the engine immediately. Check the oil level, check for
leakage of oil, and take the necessary action.

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Starting Engine in Cold Weather

WARNING
Start the engine only after sitting down in the operator's seat.
Do not attempt to start the engine by short-circuiting the engine starting circuit. Such an act may cause a serious bodily injury
or fire.
Check that there are no persons or obstacles in the surrounding area, then sound the horn and start the engine.
Never use starting aid fluids as they may cause explosions.
Exhaust gas is toxic. When starting the engine in confined spaces, be particularly careful to ensure good ventilation.

NOTICE
Before starting the engine, check that fuel control dial (2) is at the low
idle (MIN) position.
If the fuel control dial is at the FULL position, the engine will accelerate
suddenly and cause damage to the engine parts, set it to an
intermediate or low speed position.
Do not keep the strating motor rotating continuously for more than 20
seconds.
If the engine fails to start, wait for about 2 minutes and repeat from Step
2.

When starting in low temperatures, do as follows.

1. Check the lock lever (1) is at the LOCK position (L). If the lock
lever is in the FREE position (F), the engine does not start.

2. Set fuel control dial (2) at a low idle (MIN) position.

Do not set fuel control dial (2) at the high idle (MAX) position.

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3. Hold the key in starting switch (3) in the HEAT position (D), and
check that engine pre-heating monitor (4) lights up. After about
30 seconds, engine pre-heating monitor lamp (4) will flash to
indicate that pre-heating is finished.

REMARK
The monitors and gauges will light up also when the key is
turned to the HEAT position, but this is not a problem.
If the temperature is low, the monitor screen may become dark
or it may take time for the display to appear, but this is not a
problem.

4. When engine pre-heating monitor (4) flashes, turn the key in

starting switch (3) to the START position (C) to start the engine.

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

6. After starting the engine, do not touch the work equipment

control lever or travel pedal while the engine oil pressure
monitor lamp is lighted up.

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AFTER STARTING ENGINE

WARNING
If any trouble occurs, such as sudden stopping or abnormal operation, turn the starting switch to the OFF position.
If the work equipment is operated without carrying out the warming-up operation properly, the reaction of the work equipment
to the operation of the control lever will be slow and the work equipment may not move as the operator intends. To prevent such
problems, always be sure to carry out the warming-up operation fully. In cold weather particularly, be extremely careful to carry
out the warming-up operation fully.

Warming-up Operation
NOTICE
When the hydraulic oil is at a low temperature, do not perform
operations or move the levers suddenly. Always perform the
warming-up operation. This will help extend the machine life.
Do not suddenly accelerate the engine before the warming-up operation
is completed.
Do not run the engine at low or high idle continuously for more than 20
minutes. This will cause oil leaks from the turbocharger oil supply
piping. If it is necessary to run the engine at idle, apply a load from time
to time or run the engine at a mid-range speed.

REMARK
If the engine coolant temperature is above 30°C (86°F), to protect the turbocharger, the engine speed does not
rise for 2 seconds after starting, even if the fuel control dial is turned.
If the hydraulic oil temperature is low, the hydraulic oil temperature monitor display will be white.

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After starting the engine, do not immediately start operations. First, perform the following operations and checks.

1. Turn fuel control dial (2) to center position (a) between the low
idle (MIN) and high idle (MAX) positions and run the engine at
a mid-range speed under no load until the engine coolant
temperature monitor gives a green display.

2. Set lock lever (1) slowly and securely to the FREE position (F),
then raise the bucket from the ground.

3. Operate bucket control lever (3) and arm control lever (4)
slowly to move the bucket cylinder and arm cylinder to the end
of the stroke.

4. Operate the bucket for 30 seconds and the arm for 30 seconds
in turn fully for 5 minutes.
(A): Arm is pushed out
(B): Arm is pulled in
(C): Bucket is pushed out
(D): Bucket is pulled in

REMARK
If the swing lock switch (5) is set to the ON (actuated) position and
swing control lever (4) is operated at full stroke, oil temperaturerise
can be increased earlier.

(E): Left swing

(F): Right swing

NOTICE
When the work equipment is retracted, take care that it does not interfere with the machine body or ground.

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5. After performing the warming-up operation, check and be sure

all the gauges on machine monitor (6) and the caution lamps
are in the following conditions:
Radiator coolant level monitor (7): OFF
Engine oil level monitor (8): OFF
Charge level monitor (9): OFF
Fuel level monitor (10): Green display
Engine coolant temperature monitor (11): Green display
Engine oil pressure monitor (12): OFF
Engine coolant temperature gauge (13): Indicator in black
range
Fuel gauge (14): Indicator in black range
Engine pre-heating monitor (15): OFF
Air cleaner clogging monitor (16): OFF
Hydraulic oil temperature gauge (17): Indicator in black
range
Hydraulic oil temperature monitor (18): Green display

6. Check for abnormal exhaust gas color, noise, or vibration. If

any problem is found, contact your Komatsu distributor.

7. If air cleaner clogging monitor (16) lights up, clean or replace the element immediately.
For details of the method of cleaning the element, see "CHECK, CLEAN AND REPLACE AIR CLEANER
ELEMENT (PAGE 4-19)".

8. Use working mode selector switch (19) on machine monitor (6)

to select the working mode to be used.

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Working mode monitor display

1) A mode
For heavy-load operations

2) E mode
For operations with emphasis on fuel economy

3) L mode
For operations requiring fine control

4) B mode
For breaker operations

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In Cold Weather Areas

(AUTOMATIC WARMING-UP OPERATION)
This machine is equipped with an automatic warming-up device.
When the engine is started, if the engine coolant temperature is low (below 30 °C (86 °F)), the warming-up operation
is carried out automatically.
The automatic warming-up operation is canceled if the engine coolant temperature reaches the specified
temperature (30 °C (86 °F)) or if the warming-up operation is continued for 10 minutes. If the engine coolant
temperature or hydraulic oil temperature are low after the automatic warming-up operation, warm the engine up
further as follows.

NOTICE
Do not suddenly accelerate the engine before the warming-up operation
is completed.
Do not run the engine at low or high idle continuously for more than 20
minutes. This will cause oil leaks from the turbocharger oil supply
piping. If it is necessary to run the engine at idle, apply a load from time
to time or run the engine at a mid-range speed.
Never perform operations or operate the control levers when the
hydraulic oil is still a low temperature. Always continue the warming-up
operation until the hydraulic oil temperature monitor display is green.
This will extend the service life of the machine.

REMARK
If the hydraulic oil temperature is low, the hydraulic oil temperature monitor display will be white.

1. Turn fuel control dial (2) to the low idle (MIN) position and run
the engine under no load until the engine coolant temperature
monitor gives a green display.
2. To raise the hydraulic oil temperature quickly, use the
operating mode switch on the machine monitor to set to A
mode (heavy-duty operation mode).

3. Turn fuel control dial (2) to the medium speed position (a).

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4. Set lock lever (1) slowly and securely to the FREE position (F),
then raise the bucket from the ground.

5. Operate bucket control lever (3) and arm control lever (4)
slowly to move the bucket cylinder and arm cylinder to the end
of the stroke.
6. Operate the bucket for 30 seconds and the arm for 30 seconds
in turn fully for 5 minutes.
(A): Arm is pushed out
(B): Arm is pulled in
(C): Bucket is pushed out
(D): Bucket is pulled in

REMARK
If the swing lock switch (5) is set to the ON (actuated) position and
swing control lever (4) is operated at full stroke, oil temperaturerise
can be increased earlier.

(E): Left swing

(F): Right swing

NOTICE
When the work equipment is retracted, take care that it does not interfere with the machine body or ground.

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7. After the warming-up operation is completed, check that each

gauge and monitor lamp is in the following condition:
Radiator coolant level monitor (7): OFF
Engine oil level monitor (8): OFF
Charge level monitor (9): OFF
Fuel level monitor (10): Green display
Engine coolant temperature monitor (11): Green display
Engine oil pressure monitor (12): OFF
Engine coolant temperature gauge (13): Indicator in black
range
Fuel gauge (14): Indicator in black range
Engine pre-heating monitor (15): OFF
Air cleaner clogging monitor (16): OFF
Hydraulic oil temperature gauge (17): Indicator in black
range
Hydraulic oil temperature monitor (18): Green display

8. Check for abnormal exhaust gas color, noise, or vibration. If

any problem is found, contact your Komatsu distributor.

9. If air cleaner clogging monitor (16) lights up, clean or replace the element immediately.
For details of the method of cleaning the element, see "CHECK, CLEAN AND REPLACE AIR CLEANER
ELEMENT (PAGE 4-19)".

10. Turn fuel control dial (2) to the full speed (MAX) position and
carry out the operation is Step 5. for 3 to 5 minutes.
11. Repeat the following operation 3 - 5 times and operate slowly.

Boom operation RAISE ←→ LOWER

Arm operation IN ←→ OUT
Bucket operation CURL ←→ DUMP
Swing operation LEFT ←→ RIGHT
Travel (Lo) operation FORWARD ←→ REVERSE

REMARK
If the above operation is not carried out, then may be a delay in response when starting or stopping the actuation
of the travel, swing, or work equipment.

12. Use working mode selector switch (19) on machine monitor (6)
to select the working mode to be used.

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Working mode monitor display

1) A mode
For heavy-load operations

2) E mode
For operations with emphasis on fuel economy

3) L mode
For operations requiring fine control

4) B mode
For breaker operations

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NOTICE
Canceling automatic warm-up operation
If it becomes necessary in an emergency to cancel the automatic warm-up operation or to lower the engine speed to low idle, do
as follows.

1] Turn fuel control dial (2) to the full speed (MAX)

position and hold it for 3 seconds.

2] When fuel control dial (2) is returned to the low idle

(MIN) position, the engine speed will drop.

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STOPPING THE ENGINE

NOTICE
If the engine is stopped abruptly, service life of component parts of the
engine may be considerably reduced. Hence do not stop the engine
abruptly except in an emergency. If the engine has overheated, do not try
to stop it abruptly. Run it at low idling to allow it to cool down gradually, and
then stop it.

1. Run the engine at low idle for about 5 minutes to cool down
gradually.

2. Turn the key in starting switch (1) to the OFF position (A) and
stop the engine.
3. Remove the key from starting switch (1).

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MACHINE OPERATION

Preparations for Moving the Machine

WARNING
Before operating the steering levers, check the direction of the track
frame.
If the sprocket is at the front, the operation of the travel levers is
reversed.
When moving the machine, check that the area around the machine is
safe, and always sound the horn before moving.
Do not allow anyone in the area around the machine.
Remove all obstacles from the travel path of the machine.
The rear of the machine is a blind spot, be extremely careful when
traveling in reverse.
If the lever is moved inside the deceleration range, engine speed will
rise suddenly. Operate the levers carefully.
For machines equipped with a travel alarm, check that the warning
equipment works properly.

1. Set swing lock switch (1) to the ON (actuated) position and

confirm that swing lock monitor lamp (2) lights up.

2. Turn fuel control dial (3) towards the full speed position to
increase the engine speed.

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Moving Machine Forward

1. Set lock lever (4) in the FREE position (F), fold the work
equipment, and raise it 40 to 50 cm (16 to 20 in) from the
ground.

2. Operate the right and left travel levers (5), or the right or left travel pedals (6) as follows:
When sprocket (A) is at the rear of the machine:
Slowly push the levers (5) forward, or slowly depress the front
part of the pedals (6) to move the machine forward.

When sprocket (A) is at the front of the machine:

Slowly pull the levers (5) backward, or slowly depress the rear
part of the pedals (6) to move the machine forward.

3. For machines equipped with a travel alarm (if equipped), check that the alarm sounds. If the alarm does not
sound, please contact your Komatsu distributor for repair.

REMARK
In cold temperatures, if the machine travel speed is not normal, thoroughly perform the warming-up operation.
In addition, if the undercarriage is clogged with mud and the machine travel speed is not normal, remove the soil and
mud from the undercarriage.

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Moving Machine Backward

1. Set lock lever (4) in the FREE position (F), fold the work
equipment, and raise it 40 to 50 cm (16 to 20 in) from the
ground.

2. Operate the right and left travel levers (5), or the right or left travel pedals (6) as follows:
When sprocket (A) is at the rear of the machine:
Slowly pull the levers (5) backward, or slowly depress the rear
part of the pedals (6) to move the machine backward.

When sprocket (A) is at the front of the machine:

Slowly push the levers (5) forward, or slowly depress the front
part of the pedals (6) to move the machine backward.

3. For machines equipped with a travel alarm (if equipped), check that the alarm sounds. If the alarm does not
sound, please contact your Komatsu distributor for repair.

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Stopping Machine
Avoid stopping suddenly. Give yourself ample room and return the lever slowly when stopping.
1. Put the left and right travel levers (1) in the neutral position,
then stop the machine.

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MACHINE OPERATIONS AND CONTROLS OPERATION

STEERING THE MACHINE

Steering
WARNING
Before operating the travel levers, check the direction of the track frame (the position of the sprocket). If the sprocket is at the rear,
the machine moves in the reverse direction to the operation of the travel levers.

Use the travel levers to change direction.

Avoid sudden changes of direction as much as possible.
Especially when performing counter-rotation (spin turn), stop the
machine before turning.
Operate two travel levers (1) as follows.

Steering the Machine when Stopped

When turning to the left:
Push the right travel lever forward to turn to the left when traveling
forward; and pull it back to turn left when traveling in reverse.
(A): Forward left turn
(B): Reverse left turn

REMARK
When turning to the right, operate the left travel lever in the same
way.

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OPERATION MACHINE OPERATIONS AND CONTROLS

Changing Direction of the Machine

When turning to the left:
If the left travel lever is returned to the neutral position, the machine
will turn to the left.
(A): Forward left turn
(B): Reverse left turn

REMARK
When turning to the right, operate the right travel lever in the same
way.

Counter-rotation Turn (Spin Turn)

When using counter-rotation (spin turn) to turn left, pull the left
travel lever back and push the right travel lever forward.

REMARK
When using counter-rotation to turn right, pull the right travel lever
back and push the left travel lever forward.

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MACHINE OPERATIONS AND CONTROLS OPERATION

SWINGING
WARNING
The tail of the machine extends outside the tracks. Before operating the
swing, check that the area around the machine is safe.

1. Before starting the swing operation, turn swing lock switch (1)
OFF and check that swing lock monitor (2) has gone out.

2. Operate left work equipment control lever (3) to swing the

upper structure.
(A): Left swing
(B): Right swing

3. When not using the swing, turn swing lock switch (1) ON.
Check that swing lock monitor (2) lights up.

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OPERATION MACHINE OPERATIONS AND CONTROLS

WORK EQUIPMENT CONTROLS AND OPERATIONS

WARNING
If the lever is operated when the engine speed has been lowered by the auto-deceleration function, the engine speed will suddenly
rise, operate the levers carefully.

Use the control levers to operate the work equipment.

Note that when the levers are released, they return to the HOLD position and the work equipment is held in that
position.
The work equipment is operated by the left and right work equipment control levers. The left work equipment control
lever operates the arm and swing, and the right work equipment control lever operates the boom and bucket.
The movements of the lever and work equipment are as shown in the diagrams on the right. When the levers are
released, they automatically return to the neutral position and the work equipment is held in place.
If the work equipment control levers are returned to the neutral position when the machine is stopped, even if the
fuel control dial is set to FULL, the auto-deceleration mechanism will act to reduce the engine speed to a
mid-range speed.

REMARK
With this machine, an accumulator is installed in the operating circuit, if less than 15 seconds has passed since the
engine was stopped, when the starting switch is turned to the ON position even with the engine stopped, it is
possible to operate the levers to lower work equipment to the ground.
In addition, this operation can also be used to release the remaining pressure in the hydraulic cylinder circuit or to
lower the boom after the machine has been loaded onto a trailer.

Arm operation

Swing operation

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Boom operation

Bucket operation

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WORKING MODE

Working Mode
The mode selector switch can be used to switch the mode to match operating conditions and purpose, thereby
enabling work to be performed efficiently.
Make effective use of each mode as follows.
When the starting switch is turned to the ON position, the working mode is set to A mode (digging).
Use the working mode switch to set the mode to the most efficient
mode to match the type of work.

Working
Applicable operations
mode
Normal digging, loading operations
A mode
(Operations with emphasis on productivity)
Normal digging, loading operations
E mode
(Operations with emphasis on fuel consumption)
When positioning work equipment exactly
L mode
(fine-control operations)

B mode Breaker operations

NOTICE
Do not use the heavy-duty operation mode for breaker operations. If breaker operations are carried out in the heavy-duty
operation mode, there is a hazard that the hydraulic equipment may be damaged or broken.

One-Touch Power Max. Switch

The one-touch power max. Switch can be used during operations to increase the power. Make effective use of this
function whenever necessary in combination with the working mode.
Press the left knob switch and keep it pressed. The power is
increased as long as the switch is being pressed. However, the
increased power is automatically canceled after 8.5 seconds.

This function is not actuated when the working mode is set to L

mode or B mode.

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MACHINE OPERATIONS AND CONTROLS OPERATION

PROHIBITED OPERATIONS
WARNING
If it is necessary to operate the work equipment control lever when the machine is traveling, stop the machine, then operate
the control lever.
If any lever is operated when the auto-deceleration is being actuated, the engine speed will suddenly increase, so be careful
when operating.

Operations Using Swing Force

Do not use the swing force to compact soil or break objects. This
is not only dangerous, but will also drastically reduce the life of the
machine.

Operations Using Travel Force

Do not dig the bucket into the ground and use the travel force to
carry out excavation. This will damage the machine or work
equipment.

Prohibition of Operations Using Hydraulic Cylinders to Stroke Ends

If the work equipment is used with the cylinder rod operated to its
stroke end, and given impact by some external force, the hydraulic
cylinders will be damaged, causing personal injury. Avoid
operations with the hydraulic cylinder fully retracted or fully
extended.

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OPERATION MACHINE OPERATIONS AND CONTROLS

Operations Using Bucket Dropping Force

Do not use the dropping force of the machine for digging, or use the
dropping force of the bucket as s pickaxe, breaker, or pile driver.
This will drastically reduce the life of the machine.

Operations Using Machine Dropping Force

Do not use the dropping force of the machine for digging.

Sudden Lever Shifting High Speed Travel

(1) Never carry out sudden lever shifting as this may cause sudden
starting.
(2) Avoid sudden lever shifting from forward (A) to reverse (B) (or
from reverse (B) to forward (A)).
(3) Avoid sudden lever shifting change such as sudden stopping
from near top speed (lever release operation).

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GENERAL OPERATION INFORMATION

Traveling
Traveling over boulders, tree stumps, or other obstacles will cause
a big shock to the chassis (and in particular to the tracks), and this
will cause damage to the machine. For this reason, always remove
any obstacles or travel around them, or take other steps to avoid
traveling over such obstacles as far as possible.
If there is no way to avoid traveling over an obstacle, reduce the
travel speed, keep the work equipment close to the ground, and try
to travel so that the center of the track passes over the obstacle.

High Speed Travel

On uneven roadbeds such as rock beds or uneven roads with large
rocks, travel at Lo speed. When traveling at high speed, set the
idler in the forward direction.
To switch the travel speed, press travel speed selector switch
(1). The travel speed is displayed as Lo, Mi, or Hi on the monitor
display.

Permissible Water Depth

NOTICE
When driving the machine out of water, if the angle of the machine exceeds
15°, the rear of the upper structure will go under water, and water will be
thrown up by the cooling fan. This may cause the fan to break.
Be extremely careful when driving the machine out of water.

Do not drive the machine in water deeper than the center of carrier
roller (1).
Supply grease to the parts which have been under water for a long
time until the used grease is projected out of the bearings (around
the bucket pin, in particular).

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OPERATION MACHINE OPERATIONS AND CONTROLS

Digging Hard Rocky Ground

Do not attempt to directly excavate hard rocky ground with the work equipment. It is better to excavate it after
breaking up by some other means. This will not only save the machine from damage but will make for better
economy.

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TRAVELING ON SLOPES
WARNING
Turning or operating the work equipment when working on slopes may
cause the machine to lose it balance and turn over, so avoid such
operations.
It is particularly dangerous to swing downhill when the bucket is loaded.
If such operations have to be performed, pile soil to make a platform (A)
on the slope so the machine is kept horizontal during operation.
Do not travel up or down steep slopes. There is a danger that the
machine may turn over.
When traveling, raise the bucket approx. 20 to 30 cm (8 to 12 in) from the
ground.
Do not travel downhill in reverse.
Never turn on slopes or travel across slopes.
Always go down to a flat place to perform these operations. It may be
longer, but it will ensure safety.
Always operate or travel in such a way that it is possible to stop safely
at any time if the machine slips or becomes unstable.
When traveling uphill, if the shoes slip or it is impossible to travel uphill
using only the force of the tracks, do not use the pulling force of the arm
to help the machine travel uphill. There is danger that the machine may
turn over.

1. When traveling down steep hills, use the travel lever and fuel
control dial to keep the travel speed low. When traveling down
a steep hill of more than 15°, set the work equipment to the
posture shown in the diagram on the right, and lower the
engine speed.

2. When traveling up a steep hill of more than 15°, set the work
equipment to the posture shown in the diagram on the right.

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OPERATION MACHINE OPERATIONS AND CONTROLS

When traveling up a steep slope, extend the work equipment to

the front to improve the balance, keep the work equipment
approximately 20 to 30 cm (8 to 12 in) above the ground, and
travel at low speed.

Traveling Downhill
Put the travel lever in the neutral position. This will cause the brake to be automatically applied.

Engine Stopped on Slope

If the engine stops when traveling uphill, move the travel levers to the neutral position, lower the bucket to the
ground, stop the machine, then start the engine again.

Cab Doors on Slope

If the engine stops when the machine is on a slope, never use the left work equipment control lever to carry out
swing operations. The upper structure will swing under its own weight.
Do not open or close the door when the machine is on a slope. The operating effort may suddenly change.
Always keep the door locked in position when it is open and when it is closed.

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MACHINE OPERATIONS AND CONTROLS OPERATION

ESCAPE FROM MUD

Always operate carefully to avoid getting stuck in mud. If the machine does get stuck in mud, do as follows to get
the machine out.
Place the machine push-up switch at position (1). This will
increase the pushing power of the boom and make it easier to
escape.

Track on One Side Stuck

NOTICE
When using the boom or arm to raise the machine, always have the bottom
of the bucket in contact with the ground. The angle between the boom and
arm should be 90° to 110°.
The same applies when using the bucket installed in the reverse direction.

When only one side is stuck in mud, use the bucket to raise the
track, then lay boards or logs and drive the machine out.

Tracks on Both Sides Stuck

When the tracks on both sides are stuck in mud and they slip,
making it impossible for the machine to move, lay boards or logs as
explained above, and dig the bucket into the ground in front. Then
pull in the arm as in normal digging operations and put the travel
levers in the FORWARD position to pull the machine out.

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OPERATION MACHINE OPERATIONS AND CONTROLS

RECOMMENDED APPLICATIONS
In addition to the following, it is possible to further increase the range of applications by using various attachments.

Backhoe Work
A backhoe is suitable for excavating areas that are lower than the
machine.
When the condition of the machine is as shown in the diagram on
the right (angle between [bucket cylinder and link] and [arm
cylinder and arm] is 90°), the maximum excavation force is
obtained from the pushing force of each cylinder.
When excavating, use this angle effectively to optimize your
working efficiency.
The range for excavating with the arm is from a 45° angle away
from the machine to a 30° angle towards the machine.
There may be some differences depending on the excavation
depth, but try to stay within the above range rather than operating
the cylinder to the end of its stroke.

Shovel Work
A shovel is suitable for excavating at a position higher than the
machine. Shovel work is performed by attaching the bucket in the
reverse direction.

Ditching Work
Ditching work can be performed efficiently by attaching a bucket
which matches the digging operation and then setting the tracks
parallel to the line of the ditch to be excavated.
To excavate a wide ditch, first dig both sides and then finally
remove the center portion.

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MACHINE OPERATIONS AND CONTROLS OPERATION

Loading Work
In places where the swing angle is narrow, work efficiency can be
enhanced by locating the dump truck in a place easily visible to the
operator.
Loading is easier and capacity greater if you begin from the front of
the dump truck body than if loading is done from the side.

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OPERATION MACHINE OPERATIONS AND CONTROLS

BUCKET REPLACEMENT AND INVERSION

WARNING
When pins are knocked in with a hammer, pieces of metal may fly and cause serious injury.
When carrying out this operation, always wear goggles, hard hat, gloves, and other protective equipment.
When the bucket is removed, place it in a stable condition.
If pins are hit with a strong force, there is a hazard that the pin may fly out and injure people in the surrounding area. Make sure
that there is no one in the surrounding area before starting the operation.
When removing the pins, do not stand behind the bucket. In addition, be extremely careful not to put your foot under the bucket
while standing at the side for the work.
When removing or inserting pins, be extremely careful not to get your fingers caught.
Never insert your fingers into the pin holes when aligning the holes.

Stop the machine on a firm and flat surface and do the work. When performing joint work, appoint a lead and follow
that person's instructions and signals.

Replacement
1. Place the bucket in contact with a flat surface.

REMARK
When removing the pins, place the bucket so that it is in light
contact with the ground.
If the bucket is lowered strongly to the ground, the resistance will
be increased and it will be difficult to remove the pins.

NOTICE
After removing the pins, make sure that mud or sand does not get on them.
Dust seals are fitted at both ends of the bushings, be careful not to damage
them.

2. Remove the double nut on the stopper bolt for arm pin (A) and
link pin (B), remove the bolt, pull out arm pin (A) and link pin (B),
and then remove the bucket.
3. Align the arm (5) with holes (1) of the replacement bucket and
the link (6) with holes (2), then insert grease-coated pins (A)
and (B) into hole (1) and hole (2) respectively.

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MACHINE OPERATIONS AND CONTROLS OPERATION

REMARK
When installing the bucket, for arm pin portion (A), fit O-ring (3) to
bucket (4) in the position shown in the diagram on the right. After
inserting the pin, fit it in the standard groove.
For link pin portion (B), install the bucket with O-ring (3) fitted in the
standard groove.

4. Install the stopper bolts and nuts for each pin, then grease the
pin.

REMARK
Lubricate with grease thoroughly until the grease comes out
from the end face.
When replacing the bucket, replace the dust seal if it has been
damaged. If a damaged seal is used without being replaced,
sand and dirt may enter the pin portion and cause abnormal
wear of the pin.

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OPERATION MACHINE OPERATIONS AND CONTROLS

Inversion
NOTICE
The rock bucket (PC 400: if equipped, PC 450: standard) interferes with the
arm, so it cannot be reversed to carry out excavation to the front.
1. Place the bucket in contact with a flat surface.

REMARK
When removing the pins, place the bucket so that it is in light
contact with the ground.
If the bucket is lowered strongly to the ground, the resistance will
be increased and it will be difficult to remove the pins.

NOTICE
After removing the pins, make sure that mud or sand does not get on them.
Dust seals are fitted at both ends of the bushings, be careful not to damage
them.

2. Remove the double nut on the stopper bolt for arm pin (A) and
link pin (B), remove the bolt, pull out arm pin (A) and link pin (B),
and then remove the bucket.

3. After removing the bucket, reverse it.

4. Align arm (5) with replacement bucket hole (1), then align link
(6) with hole (2), coat pins (A) and (B) with grease, and install.

REMARK
When reversing, do not install an O-ring. Keep the O-ring in a safe
place until using it next.

5. Install the stopper bolts and nuts for each pin, then grease the
pin.

REMARK
Lubricate with grease thoroughly until the grease comes out
from the end face.
When replacing the bucket, replace the dust seal if it has been
damaged. If a damaged seal is used without being replaced,
sand and dirt may enter the pin portion and cause abnormal
wear of the pin.

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MACHINE OPERATIONS AND CONTROLS OPERATION

PARKING MACHINE
WARNING
Avoid stopping suddenly. Give yourself ample room when stopping.
When stopping the machine, select flat hard ground and avoid
dangerous places. If it is unavoidably necessary to park the machine on
a slope, insert blocks underneath the track shoes. As an additional
safety measure, thrust the bucket into the ground.
If the control lever is touched by accident, the work equipment or the
machine may move suddenly, and this may lead to a serious accident.
Before leaving the operator's compartment, always set the lock lever
securely to LOCK position.

1. Put left and right travel levers (1) in the neutral position.
The machine stops.

2. Turn fuel control dial (2) to lower the engine speed to low idle.

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OPERATION MACHINE OPERATIONS AND CONTROLS

3. Lower the bucket horizontally until the bottom touches the

ground.

4. Set lock lever (3) in the LOCK position.

5. Stop the engine. For details on the procedure for stopping the engine, see "STOPPING THE ENGINE (PAGE
3-99)".

CHECK AFTER SHUT OFF ENGINE

Check the engine coolant temperature, engine oil pressure, and
fuel level on the machine monitor.

REMARK
After stopping the engine, if the starting switch is turned within
approx. 10 seconds to the ON or START position to start the
engine again, the monitor display is not reset, and the screen
before the starting switch was turned OFF is displayed.

MACHINE INSPECTION AFTER DAILY WORK

1. Walk around the machine and check the work equipment, machine exterior, and undercarriage, also check for
any leakage of oil or coolant. If any problems are found, repair them.
2. Fill the fuel tank.
3. Check the engine compartment for paper and debris. Clean out any paper and debris to avoid a fire hazard.
4. Remove any mud affixed to the undercarriage.

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MACHINE OPERATIONS AND CONTROLS OPERATION

LOCKING
Always lock the following places.
1. Door of operator's cab
Always remember to close the window.
2. Fuel tank filler port
3. Engine hood
4. Battery box cover
5. Left side door of the machine
6. Right side door of the machine
7. Hydraulic tank filler port

REMARK
Use the starting switch key to lock and unlock all these places.

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OPERATION TRANSPORTATION

TRANSPORTATION
When transporting the machine, observe all related laws and regulations, and be careful to assure safety.

PRECAUTIONS FOR TRANSPORTATION

WARNING
This machine must be divided into several units for transportation.
When transporting the machine, please consult your Komatsu distributor.

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TRANSPORTATION OPERATION

LOADING AND UNLOADING WITH TRAILER

WARNING
Always turn the auto-deceleration switch OFF (cancel) during loading
and unloading operations.
If the auto-deceleration switch is left ON, the machine may suddenly
start moving.
When loading or unloading the machine on a trailer, always travel at low
speed. Do not operate the travel speed selector switch.
Run the engine at low idle, set to Lo speed, and operate the machine
slowly when loading or unloading.
Do not carry out loading or unloading operations during the automatic
warming-up operation.
If the automatic warming-up operation is canceled before completion,
the travel speed may suddenly change.
Select firm, level ground when loading or unloading the machine.
Maintain a safe distance from the edge of the road.
Use ramps with ample width, length, thickness, and strength and install
them at a maximum slope of 15°.
When using piled soil, compact the piled soil fully and prevent the slope
face from collapsing.
Remove all mud and dirt from the machine tracks before starting in
order to prevent the machine from slipping on the ramps.
Be sure that the ramp surface is clean and free of water, snow, grease,
oil, or ice.
Never correct your steering on the ramps. There is a hazard that the
machine may turn over.
If necessary, drive off the ramps, correct the direction, then enter the
ramps again.
It is dangerous to use the work equipment for loading and unloading
operations.
When on the ramps, do not operate any lever except the travel lever.
The center of gravity of the machine will change suddenly at the joint
between the ramps and the track or trailer, and there is a hazard of the
machine losing its balance. Travel slowly over this point.
When swinging the upper structure on the trailer, the trailer is unstable,
pull in the work equipment and swing slowly.

When loading or unloading, always use ramps or a platform. Proceed as follows.

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OPERATION TRANSPORTATION

Loading
1. Load and unload on firm level ground only.
Maintain a safe distance from the edge of a road.
2. Apply the trailer brakes securely, then put blocks (1) under the
tires to prevent the trailer from moving.
Set left and right ramps (2) parallel to each other and
equally spaced to the left and right of center (3) of the trailer.
Make angle of installation (4) a maximum of 15°. If the
ramps bend a large amount under the weight of the
machine, put blocks under the ramps to prevent them from
bending.

3. Set the travel speed selector switch to Lo (low speed travel).

To switch the travel speed, press travel speed selector
switch (1). The travel speed is displayed as Lo, Mi, or Hi on
the monitor display.

4. Turn auto-deceleration switch (1) OFF and operate the fuel

control dial to set the engine speed to low idle.
Each time auto-deceleration switch (1) is pressed, it
switches OFF J ON J OFF in turn.
When auto-deceleration switch (1) is turned OFF, display
monitor (2) goes out.

5. Turn the swing lock switch ON to apply the swing lock.

When the swing lock switch is turned ON, display monitor
(3) lights up.

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TRANSPORTATION OPERATION

6. If the machine is equipped with work equipment, set the work

equipment at the front, and travel forward to load it; if it has no
work equipment, travel in reverse to load it.
Follow instructions and signals of a conductor particularly
when traveling in reverse.

7. Before moving onto the ramps, make sure that the machine is
positioned in a straight line with the ramps and that the
centerline of the machine matches that of the trailer.
Align the direction of travel with the ramps and travel slowly.
Lower the work equipment as far as possible without causing
interference.
When on the ramps, operate only the travel lever. Do not
operate any other lever.
8. When the machine travels over the rear wheels of the trailer, it
becomes unstable, drive slowly and carefully. (Never operate
the steering.)
9. At the moment the machine passes the rear wheels, it tilts
forward, be careful not to let the work equipment hit the trailer
body. Drive the machine forward to the specified position, then
stop the machine.
10. Turn the swing lock switch OFF to release the swing lock, then
swing the upper structure slowly 180°.
11. Stop the machine at the specified position on the trailer.

12. Turn the swing lock switch ON to lock the swing lock.
When the swing lock switch is turned ON, display monitor
(3) lights up.

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OPERATION TRANSPORTATION

Securing Machine
NOTICE
Stow the antenna and reassemble the mirrors so that they are within the width of the machine.
To prevent damage to the bucket cylinder during transportation, fit a wooden block at one end of the bucket cylinder to prevent
it from touching the floor.

Load the machine onto a trailer as follows:

1. Extend the bucket and arm cylinders fully, then lower the boom
slowly.

2. Set the lock lever securely to the LOCK position (L).

3. Stop the engine, then remove the key from the starting switch.
4. Lock the window glass, roof window, front window, operator's
seat door, side cover, engine hood, and battery box cover
securely.

5. Place blocks under both ends of the tracks to prevent the

machine from moving during transportation, and secure the
machine with chains or wire rope of suitable strength.
Be particulary careful to secure the machine in position so it
does not slip to the side.

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TRANSPORTATION OPERATION

Rearview Mirrors
The mirrors are at the positions shown in the diagram on the right.
If they are damaged, or are to be removed for shipment, or are to
be installed again, use the following procedure.

Removal
Left mirror
1. Loosen locknut (2) of mirror (1), then remove mirror (1) from
support (3).
2. Loosen bolt (4) and remove support (3) and clamp (5) from the
handrail.

Right mirror
3. Loosen locknut (2) of mirror (1), then remove mirror (1) from
support (3).
4. Loosen bolt (4) and remove support (3) and clamp (5) from the
handrail.

Installation
Left mirror
1. Install support (3) and clamp (5) to the handrail,then tighten
with bolt (4).
2. Install mirror (1) to bracket (3),then tighten locknut (2).

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OPERATION TRANSPORTATION

Right mirror
3. Install support (3) and clamp (5) to the handrail,then tighten
with bolt (4).
4. Install mirror (1) to bracket (3),then tighten lock bolt (2).

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TRANSPORTATION OPERATION

Unloading
1. Load and unload on firm level ground only. Maintain a safe distance from the edge of a road.
2. Apply the trailer brakes securely, then put blocks (1) under the
tires to prevent the trailer from moving.
Set left and right ramps (2) parallel to each other and
equally spaced to the left and right of center (3) of the trailer.
Make angle of installation (4) a maximum of 15°. If the
ramps bend a large amount under the weight of the
machine, put blocks under the ramps to prevent them from
bending.
3. Remove the chains and wire ropes fastening the machine.
4. Start the engine.
Warm the engine up fully.
5. Set the lock lever to FREE position (F).

6. Set the travel speed selector switch to Lo (low speed travel).

Press travel speed selector switch (1) to set the travel
speed. The travel speed (Lo, Mi, Hi) is displayed on monitor
display GG.

7. Turn auto-deceleration switch (1) OFF and operate the fuel

control dial to set the engine speed to low idle.
Each time auto-deceleration switch (1) is pressed, it
switches OFF J ON J OFF in turn.
When auto-deceleration switch (1) is turned OFF, monitor
display GG (2) goes out.

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OPERATION TRANSPORTATION

8. Turn the swing lock switch OFF to release the swing lock.
When the swing lock switch is turned OFF, display monitor
(4) goes off.

9. Raise the work equipment, pull in the arm under the boom,
then move the machine slowly.
10. When the machine is horizontal on top of the rear wheels of the
trailer, stop the machine.

11. When moving from the rear of the trailer on to the ramps, set
the angle of the arm and boom to 90° to 110°, lower the bucket
to the ground, then move the machine slowly.

12. When moving down the ramps, operate the boom and arm
slowly to lower the machine carefully until it is completely off
the ramps.

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TRANSPORTATION OPERATION

LIFTING MACHINE
WARNING
The operator carrying out the lifting operation using a crane must be a properly qualified crane operator.
Never raise the machine with any worker on it.
Always make sure that the wire rope is of ample strength for the weight of this machine.
When lifting, keep the machine horizontal.
When carrying out lifting operations, set the lock lever to the LOCK position to prevent the machine from moving unexpectedly.
Never enter the area under or around a raised machine.
Never try to lift the machine in any posture other than the posture given in the procedure below or using lifting equipment other
than in the procedure below.
There is a hazard that the machine may lose its balance.

NOTICE
The lifting procedure applies to machines with standard specifications.
The method of lifting differs according to attachments and options actually installed on the machine. For the proper lifting
procedures, contact your Komatsu distributor.

For details of the weight, see "SPECIFICATIONS (PAGE 5-2)".

When lifting the machine, carry out the operation on flat ground as follows.
1. Start the engine, then the swing the upper structure so that the work equipment will be on the side of sprocket
(1).
2. Extend the bucket cylinder and arm cylinder fully, then lower
the work equipment to the ground as shown in the diagram on
the right using the boom cylinder.

3. Set the lock lever securely to the LOCK position (L).

4. Stop the engine, check that there is nothing around the operator's compartment, then get off the machine.
Close the cab door and front glass securely.

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OPERATION TRANSPORTATION

5. Pass wire ropes between the 1st and 2nd track rollers from the
front and between the 1st and 2nd track rollers from the rear.
However, for machines equipped with a full roller guard for the
track roller, pass the wire rope under the track.
6. Set the lifting angle (A) of the wire rope to 30° to 40°, then lift
the machine slowly.
7. After the machine comes off the ground, check the hook
condition and the lifting posture, and then lift slowly.

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TRANSPORTATION OPERATION

TRANSPORTATION POSTURE
This machine is separated into four kits for transportation: (1) upper structure, (2) cab, (3) work equipment, (4)
others. When transporting the machine, please ask your Komatsu distributor to divide the machine up into kits.

Posture for Each Unit

Upper Structure + Undercarriage

Variable gauge specification machine
The value given in [ ] for the overall width is the value when the track frame gauge has been retracted.

Item Unit PC400 PC400LC PC450 PC450LC

mm 3,275 3,275 3,275 3,275
A
(ft in) (10' 9") (10' 9") (10' 9") (10' 9")
mm 5,850 6,035 5,850 6,035
B
(ft in) (19' 2") (19' 10") (19' 2") (19' 10")
3,490 3,590 3,490 3,490
Overall mm (11' 5") (11' 9") (11' 5") (11' 5")
width (ft in) [2,990] [2,990] [2,990] [2,990]
(9' 10") (9' 10") (9' 10") (9' 10")
kg 25,170 26,270 25,670 26,370
Weight
(lb) (55,500) (57,925) (56,602) (58,146)

Fixed gauge specification machine

Item Unit PC400 PC400LC PC450 PC450LC

mm 3,275 3,275 3,275 3,275
A
(ft in) (10' 9") (10' 9") (10' 9") (10' 9")
mm 5,850 6,035 5,850 6,035
B
(ft in) (19' 2") (19' 10") (19' 2") (19' 10")
Overall mm 3,340 3,440 3,340 3,340
width (ft in) (10' 11") (11' 3") (10' 11") (10' 11")
kg 24,000 25,000 24,460 25,460
Weight
(lb) (52,920) (55,125) (53,934) (56,139)

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OPERATION TRANSPORTATION

Upper Structure + Undercarriage (without cab)

Variable gauge specification machine
The value given in [ ] in the table below is the value when the track frame gauge has been retracted.

Item Unit PC400 PC400LC PC450 PC450LC

mm 3,115 3,115 3,115 3,115
A
(ft in) (10' 3") (10' 3") (10' 3") (10' 3")
mm 5,850 6,035 5,850 6,035
B
(ft in) (19' 2") (19' 10") (19' 2") (19' 10")
3,490 3,590 3,490 3,490
Overall mm (11' 5") (11' 9") (11' 5") (11' 5")
width (ft in) [2,990] [2,990] [2,990] [2,990]
(9' 10") (9' 10") (9' 10") (9' 10")
kg 24,890 25,990 25,380 26,090
Weight
(lb) (54,882) (57,308) (56,963) (57,528)

Fixed gauge specification machine

Item Unit PC400 PC400LC PC450 PC450LC

mm 3,115 3,115 3,115 3,115
A
(ft in) (10' 3") (10' 3") (10' 3") (10' 3")
mm 5,850 6,035 5,850 6,035
B
(ft in) (19' 2") (19' 10") (19' 2") (19' 10")
Overall mm 3,340 3,440 3,340 3,340
width (ft in) (10' 11") (11' 3") (10' 11") (10' 11")
kg 23,720 24,720 24,170 25,180
Weight
(lb) (52,303) (54,508) (53,295) (55,522)

Cab

Item Unit PC400, PC400LC PC450, PC450LC

A mm (ft in) 1,670 (5' 6") 1,670 (5' 6")
B mm (ft in) 1,840 (6') 1,840 (6')
Overall width mm (ft in) 1,000 (3' 3") 1,000 (3' 3")
Weight kg (lb) 280 (617) 280 (617)

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TRANSPORTATION OPERATION

Work Equipment
Boom

Item Unit PC400, PC400LC PC450, PC450LC

A mm (ft in) 7,280 (23' 11") 7,280 (23' 11")
B mm (ft in) 1,730 (5' 8") 1,760 (5' 8")
Overall width mm (ft in) 985 (3' 3") 985 (3' 3")
Weight kg (lb) 4,600 (10,143) 4,770 (10,518)

Arm, Bucket

Item Unit PC400, PC400LC PC450, PC450LC

A mm (ft in) 4,890 (16' 1") 5,050 (16' 7")
B mm (ft in) 1,950 (6' 5") 1,950 (6' 5")
Overall width mm (ft in) 1,620 (5' 4") 1,620 (5' 4")
Weight kg (lb) 3,430 (7,563) 4,230 (9,327)

Others
The value given in [ ] for the overall width is the value for the America specification machine.
Counterweight

Item Unit PC400, PC400LC PC450, PC450LC

A mm (ft in) 1,145 (3' 9") 1,145 (3' 9")
B mm (ft in) 2,995 (9' 10") 2,995 (9' 10")
C mm (ft in) 970 (3' 2") 970 (3' 2")
9,230 (20,352) 9,230 (20,352)
Weight kg (lb)
[9,510 (20,970)] [9,510 (20,970)]

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OPERATION COLD WEATHER OPERATION

COLD WEATHER OPERATION

COLD WEATHER OPERATION INFORMATION
If the temperature becomes low, it becomes difficult to start the engine, and the coolant may freeze, so do as follows.

Fuel and Lubricants

Change to fuel and oil with low viscosity for all components. For details of the specified viscosity, see
"LUBRICANTS, FUEL AND COOLANT SPECIFICATIONS (PAGE 4-9)".

Cooling System Coolant

WARNING
Antifreeze 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 at once.
When changing the coolant or when handling coolant containing antifreeze that has been drained when repairing the radiator,
please contact your Komatsu distributor or request a specialist company to carry out the operation. Antifreeze is toxic. Do not
let it flow into drainage ditches or spray it onto the ground surface.
Antifreeze is flammable. Do not bring any flame close. Do not smoke when handling antifreeze.

NOTICE
Never use methanol, ethanol, or propanol-based antifreeze.
Never use any water-leakage prevention agent or any antifreeze containing such an agent.
Do not mix different types of antifreeze.

For details of the antifreeze mixture when changing the coolant, see "CLEAN INSIDE OF COOLING SYSTEM
(PAGE 4-24)".
Use a Permanent Antifreeze (ethylene glycol mixed with corrosion inhibitor, antifoam agent, etc.) meeting the
standard requirements as shown below. With permanent antifreeze, no change of coolant is required for a year. If
it is doubtful that an available antifreeze meets the standard requirements, ask the supplier of that antifreeze for
information.
Standard requirements for permanent antifreeze
SAE J1034
FEDERAL STANDARD O-A-548D

REMARK
In areas where permanent antifreeze is not available, it is possible to use antifreeze whose main component is
ethylene glycol and does not contain any corrosion inhibitor. (Such antifreeze can be used for the winter season
only.) However, in such a case, the coolant must be changed twice a year (spring and autumn), so use permanent
antifreeze when possible.

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COLD WEATHER OPERATION OPERATION

Battery
WARNING
The battery generates flammable gas, so do not bring fire or sparks near the battery.
Battery electrolyte is dangerous. 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 to the bodywork, wash it off immediately with water.
If the battery electrolyte is frozen, do not charge the battery or start the engine with a different power source. There is danger
that the battery may explode.
Battery electrolyte is toxic, so do not let it flow into drainage ditches or spray it on to the ground surface.
If the breather hole in the battery cap becomes clogged, there is danger of damage to the battery. If the breather hole is
clogged, clean it.

When the ambient temperature drops, the capacity of the battery will also drop. If the battery charge ratio is low, the
battery electrolyte may freeze. Maintain the battery charge as close as possible to 100%. Insulate it against cold
temperature to ensure the machine can be started easily the next morning.

REMARK
Measure the specific gravity and calculate the charging rate from the following conversion table.

Electrolyte
Temperature
20 0 -10 -20
Charging (°C)
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
As the battery capacity drastically drops in low temperatures, cover or remove the battery from the machine, store
the battery in a warm place, and install it again the next morning.
If the electrolyte level is low, add distilled water in the morning before beginning work. Do not add water after the
day's work to prevent diluted electrolyte in the battery from freezing during the night.

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OPERATION COLD WEATHER OPERATION

Monitor
A feature of the liquid-crystal monitor is that the screen becomes dark and is difficult to read in cold weather
(particularly with the starting switch ON).
In this case, adjust the brightness and contrast of the screen.
For details, see "Liquid Crystal Monitor Adjustment Switch (PAGE 3-28)".

If the screen is dark, increase the brightness and contrast (extend the scale in the + E direction) to make the screen
brighter and easier to read.

Brightness

Contrast

Guideline for bar display for brightness and contrast in cold weather

Ambient temperature Brightness Contrast

-10°C (14°F) 7 (max) 5-4
-20°C (-4°F) 7 7-6

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COLD WEATHER OPERATION OPERATION

AFTER DAILY WORK COMPLETION

WARNING
Performing idle-running 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.
Park the machine on hard, 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 be moved the next morning.
Open the drain valve and drain any water collected in the fuel system to prevent it from freezing.
Fill the fuel tank to capacity. This minimizes moisture condensation in the tank when the temperature drops.
After operation in water or mud, remove water from undercarriage as described below to extend undercarriage
service life.
1. Swing 90° with engine at low idle and bring the work equipment
to the side of the track.
2. Jack up the machine until the track is raised slightly from the
ground. Rotate the track under no load. Repeat this procedure
on both the left and right sides.

AFTER COLD WEATHER SEASON

When the season changes and the weather becomes warmer, do as follows.
Replace all fuel and oil with the specified fuel and oil.
For details, see "LUBRICANTS, FUEL AND COOLANT SPECIFICATIONS (PAGE 4-9)".

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OPERATION LONG TERM STORAGE

LONG TERM STORAGE

BEFORE STORAGE
NOTICE
To protect the hydraulic cylinder piston rod while in storage, keep the work
equipment in the posture shown at right.
(This prevents rust from developing on the piston rod)

When putting the machine in storage for a long time (more than one month), do as follows.
Clean and wash all parts, then store the machine indoors. If the machine has to be stored outdoors, select level
ground and cover the machine with canvas.
Completely fill the fuel tank. This prevents moisture from collecting.
Lubricate and change the oil before storage.
Coat the exposed portion of the hydraulic cylinder piston rod with grease.
Disconnect the negative terminals of the battery and cover it or remove it from the machine and store it separately.
Lock each control lever and pedal with the lock lever and pedal lock.
Set the stop valve to the LOCK position on machines ready for attachments. Install the blind plugs to the elbows.
Set the selector valve on the machines which can install attachments to the "Where no attachment is mounted"
position.

DURING STORAGE
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, also charge the battery.
For machines equipped with an air conditioner, run the air conditioner.

AFTER STORAGE
NOTICE
If the machine has been stored without carrying out the monthly rust-prevention operation, consult your Komatsu distributor
before using it.

When using the machine after long-term storage, do as follows 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.

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LONG TERM STORAGE OPERATION

STARTING MACHINE AFTER LONG-TERM STORAGE

When starting the engine after the machine has been in storage for a long time, perform the automatic warming-up
operation.
If the engine is started according to the starting procedure for cold weather, the warming-up operation is performed
automatically.
(For details, see "Starting Engine in Cold Weather (PAGE 3-88)" and "In Cold Weather Areas (PAGE 3-94)".)

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OPERATION TROUBLES AND ACTIONS

TROUBLES AND ACTIONS

RUNNING OUT OF FUEL
When starting the engine again after running out of fuel, fill with fuel, then bleed the air from the fuel system before
starting the engine.
Always watch the fuel level and be careful not to run out of fuel.
If the engine has stopped because of lack of fuel, it is necessary to use the priming pump to bleed the air completely
from the fuel circuit.

Procedure for Bleeding Air

CAUTION
This engine consists of higher precision parts than on the conventional fuel injection pump and nozzle, so if dirt gets in, it will
cause problems. If there is any dirt stuck to the fuel line, use fuel to wash it off completely.
Be careful when opening the air bleed plug at the fuel filter head and the air bleeder of the supply pump. The system is still
under pressure and fuel may spurt out.

1. Loosen air bleed plug (A), (B) at the fuel filter head (1).
2. Loosen the knob of priming pump (2), then pump the knob until
no more bubbles come out of air bleed plug (A).
3. Wrap sealing tape around air bleed plug (A) before tightening
it.
4. Operate the priming pump again and check that no more
bubbles come out with the fuel from air bleed plug (B).
5. Tighten air bleed plug (B).
Tightening torque: 4.9 to 6.9 N·m (0.5 to 0.7 kgf·m, 3.6 to 5.1
lbft)

6. Loosen air bleeder (3) of the supply pump.

7. Pump priming pump (2) approx. 90 - 100 times until no more
bubbles come out with the fuel from air bleeder (3), then tighten
air bleeder (3).
Tightening torque: 4.9 to 6.9 N·m (0.5 to 0.7 kgf·m, 3.6 to 5.1
lbft)

8. Continue pumping (approx. 50 times) until the priming pump (2) becomes stiff and the overflow valve release
sound becomes continuous.

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TROUBLES AND ACTIONS OPERATION

9. Push in the knob of priming pump (2) and tighten it.

10. Turn the key in the starting switch to the START position and start the engine.
When doing this, do not crank the starting motor continuously for more than 20 seconds. If the engine does not
start, wait for at least 2 minutes, then try again. Perform this operation a maximum of 4 times.
11. If the engine does not start, repeat the operation from Step 1.

PHENOMENA THAT ARE NOT FAILURES

Note that the following phenomena are not failures:
When the arm control lever is operated to the IN position and the
work equipment is lowered under no load from a high position,
the arm speed will drop momentarily when the arm is more or
less at the vertical position.

When the bucket control lever is operated to the CURL position

and the work equipment is lowered under no load from a high
position, the bucket speed will drop momentarily when the
bucket teeth are more or less at the horizontal position.
The bucket or arm will fluctuate by itself during heavy-duty
digging operations.

When starting or stopping the swing, noise will be emitted from the brake valve.
When going down a steep slope at low speed, a noise will be emitted from the travel motor brake valve.

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OPERATION TROUBLES AND ACTIONS

TOWING THE MACHINE

WARNING
Serious injury or death could result if a disabled machine is towed
incorrectly or if there is a mistake in the selection or inspection of the wire
rope.
Always check that the wire rope used for towing has ample strength for
the weight of the machine being towed.
Never use a wire rope which has cut strands (A), reduced diameter (B),
or kinks (C). There is danger that the rope may break during the towing
operation.
Always wear leather gloves when handling wire rope.
Never tow a machine on a slope.
During the towing operation, never stand between the towing machine
and the machine being towed.
Operate the machine slowly and be careful not to apply any sudden load
to the wire rope.

NOTICE
The maximum towing capacity for this machine is 303,030N (30,900 kgf).
Always carry out towing operations within the maximum towing capacity.

If the machine sinks in mud and cannot get out under its own
power, or if the drawbar pull of the excavator is being used to tow
a heavy object, use a wire rope as shown in the diagram on the
right.
Place pieces of wood between wire ropes and body to prevent
damage to ropes and body.
Hold the wire rope level and direct it straight to the track frame.
When towing a machine, travel at a speed of less than 1 km/h for
a distance of only a few meters to a place that is suitable for
carrying out repairs.
This is for use only in emergencies.

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TROUBLES AND ACTIONS OPERATION

LIGHTWEIGHT TOWING HOLE

WARNING
The shackle must always be used.
Hold the rope level and direct it straight to the track frame.
Move the machine slowly in the Lo mode.

There is a hole in the track frame to fit the shackle when towing light
objects.

Permissible towing load: Max. 154,000N(16,000 kgf)

SEVERE JOB CONDITION

When carrying out digging operations in water, if the work equipment mounting pin goes into the water, carry out
greasing every time the operation is carried out.
For heavy-duty operations and deep digging, carry out greasing of the work equipment mounting pins every time
before operation.
After greasing, operate the boom, arm and bucket several times, then grease again.

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OPERATION TROUBLES AND ACTIONS

DISCHARGED BATTERY
WARNING
It is dangerous to charge a battery when mounted on a machine. Make
sure that it is dismounted before charging.
When checking or handling the battery, stop the engine and turn the
starting switch key to the OFF position.
The battery generates hydrogen gas, so there is a hazard of explosion.
Do not bring lighted cigarettes near the battery, or do anything that will
cause sparks.
Battery electrolyte is dilute sulphuric acid, and it will attack your clothes
and skin. If it gets on your clothes or on your skin, immediately wash it
off with a large amount of water. If it gets in your eyes, wash it out with
fresh water and consult a doctor.
When handling batteries, always wear protective goggles and rubber
gloves.
When removing the battery, first disconnect the cable from the ground
(normally the negative (-) terminal) (diagram A). When installing, install
the positive (+) terminal first (diagram B).
If a tool touches between at the positive (+) terminal and the chassis,
there is danger that it will cause a spark, so be extremely careful.
If the terminals are loose, there is danger that the defective contact may
generate sparks that will cause an explosion. Terminals should be
connected firmly.
When removing or installing the terminals, check which is the positive
(+) terminal and which is the negative (-) terminal.

Battery Removal and Installation

Before removing the battery, remove the ground cable (normally connected to the negative (-) terminal).
If any tool touches between the positive terminal and the chassis, there is a hazard of sparks being generated.
When installing the battery, connect the ground cable last.
When replacing the battery, secure it with battery hold-down.
Tightening torque:Tightening battery terminal: 9.8 to 14.7 N·m (1 to 1.5 kgf·m, 7.2 to 10.8 lbft)

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TROUBLES AND ACTIONS OPERATION

Battery Charges
When charging the battery, if the battery is not handled correctly,
there is a hazard that the battery may explode. Always follow the
instructions of "DISCHARGED BATTERY (PAGE 3-149)" and the
instruction manual accompanying the charger, and do as follows.

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 explosion.
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 negative (-) terminal of the
battery. Be sure to attach the clips securely.
Set the charging current to 1/10 of the value of the rated battery capacity; when carrying out rapid charging, set
it to less than the rated battery capacity.
If the charger current is too high, the electrolyte will leak or 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.
There is a danger that this will ignite the battery electrolyte and cause the battery to explode.
Do not use or charge the battery if the battery electrolyte level is below the LOWER LEVEL line. This may cause
an explosion. Check the battery electrolyte level periodically and add distilled water to bring the electrolyte level
to the UPPER LEVEL line.

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OPERATION TROUBLES AND ACTIONS

Starting Engine with Booster Cables

When starting the engine with a booster cable, do as follows:

Connecting and Disconnecting Booster Cables

WARNING
When connecting the cables, never contact the positive (+) and negative
(-) terminals.
When starting the engine with a booster cable, always wear safety
glasses.
Be careful not to let the normal machine and problem machine contact
each other. This prevents sparks from generating near the battery which
could ignite the hydrogen gas given off by the battery. If hydrogen gas
explodes, it could cause serious injury.
Be careful not to make a mistake when connecting a booster cable. In
the last connection (to the upper structure frame), a spark will be
caused, connect the cable to a spot as far away from the battery as
possible. (Avoid the work equipment, however, because it is not a good
conductor)
When removing the booster cable, exercise good care so that the
booster cable clips may not contact each other, or they contact the
chassis.

NOTICE
The starting system for this machine uses 24V. For the normal machine, also use a 24V battery.
The size of the booster cable and clip should be suitable for the battry size.
The battery of the normal machine must be the same capacity as that of the engine to be started.
Check the cables and clips for damage or corrosion.
Make sure that the cables and clips are firmly connected.
Check that the lock levers and parking brake levers of both machine are in the LOCK position.
Check that each lever is in the NEUTRAL position.

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TROUBLES AND ACTIONS OPERATION

Booster Cable Connection

Keep the starting switch of the normal machine and problem
machine in the OFF position.
Connect the booster cable as follows, in the order of the numbers
marked in the diagram.
1. Connect one clip of booster cable (A) to the positive (+)
terminal of the problem machine.
2. Connect the other clip of booster cable (A) to the positive (+)
terminal of the normal machine.
3. Connect one clip of booster cable (B) to the negative (-)
terminal of the normal machine.
4. Connect the other clip of booster cable (B) to the upper
structure frame of the problem machine.

X: Battery on normal machine

Y: Battery on problem machine
Z: Upper structure frame on problem machine

Starting the Engine

WARNING
Always check that the lock lever is set to the LOCK position, regardless of whether the machine is working normally or has failed.
Check also that all the control levers are in the HOLD or neutral position.

1. Make sure the clips are firmly connected to the battery terminals.
2. Start engine of the normal machine and run it at high idle speed.
3. Turn the starting switch of the problem machine to the START position and start the engine.
If the engine doesn't start at first, try again after 2 minutes or so.

Booster Cable Disconnection

After the engine has started, disconnect booster cables in the
reverse order in which they were connected.
1. Remove one clip of booster cable (B) from the revolving frame
of the problem machine.
2. Remove the other clip of booster cable (B) from the negative (-)
terminal of the normal machine.
3. Remove one clip of booster cable (A) from the positive (+)
terminal of the normal machine.
4. Remove the other clip of booster cable (A) from the positive (+)
terminal of the problem machine.

X: Battery on normal machine

Y: Battery on problem machine
Z: Upper structure frame on problem machine

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OPERATION TROUBLES AND ACTIONS

OTHER TROUBLE

Electrical System
( ): Always contact your Komatsu distributor when dealing with these items.
In cases of problems or causes which are not listed below, contact your Komatsu distributor for repairs.

Problem Main causes Remedy

Lamp does not glow brightly even Defective wiring, deterioration of ( Check, repair loose terminals,
when the engine runs at high speed battery disconnections, replace battery)
Lamp flickers while engine is Loose fan belt Check fan belt tension, replace
running
Charge level monitor does not go Defective alternator ( Replace)
out even when engine is running Defectivr wiring ( Check, repair)
Abnormal noise is generated from Defective alternator ( Replace)
alternator
Starting motor does not turn when Defective wiring ( Check, repair)
starting switch is turned to ON Defective starting motor ( Replace)
Insufficient battery charge Charge
Pinion of starting motor keeps Insufficient battery charge Charge
going and out Defective safety relay ( Replace)
Starting motor turns engine Insufficient battery charge Charge
sluggishly Defective starting motor ( Replace)
Starting motor disengages before Defective wiring, defective ring ( Check, repair)
engine starts gear pinion
Insufficient battery charge Charge
Engine pre-heating monitor does Defective wiring ( Check, repair)
not light Defective heater relay ( Replace)
Defective monitor ( Replace)
Oil pressure monitor does not light Defective monitor ( Replace)
up when engine is stopped Defective caution lamp switch ( Replace)
(starting switch at ON position)
Outside of electrical heater is not Defective wiring ( Check, repair)
warm when touched by hand Disconnection in electric heater ( Replace)
Defective operation of heater ( Replace)
relay switch

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.

TROUBLES AND ACTIONS OPERATION

Chassis
( ): Always contact your Komatsu distributor when dealing with these items.
In cases of problems or causes which are not listed below, contact your Komatsu distributor for repairs.

Problem Main causes Remedy

Speed of travel, swing, boom, arm, Lack of hydraulic oil Add oil to specified level, see
bucket is slow CHECK BEFORE STARTING
Pump generates abnormal noise Clogged element in hydraulic Clean, see EVERY 2000
(sucking in air) tank strainer, lack of oil HOURS SERVICE
Excessive rise in hydraulic oil Loose fan belt Check fan belt tension, replace
temperature Dirty oil cooler Clean, see EVERY 500 HOURS
SERVICE
Lack of hydraulic oil Add oil to specified level, see
CHECK BEFORE STARTING
Track comes off Track too loose Adjust track tension, see WHEN
Abnormal wear of sprocket REQUIRED
Boom rises slowly, does not rise Lack of hydraulic oil Add oil to specified level,
CHECK BEFORE STARTING
Does not swing Swing lock switch still applied Turn swing lock switch OFF

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OPERATION TROUBLES AND ACTIONS

Engine
( ): Always contact your Komatsu distributor when dealing with these items.
In cases of problems or causes which are not listed below, contact your Komatsu distributor for repairs.

Problem Main causes Remedy

Engine oil pan oil level is low Add oil to specified level, see
(sucking in air) CHECK BEFORE STARTING
Clogged oil filter cartridge Replace cartridge, see
EVERY 500 HOURS SERVICE
Engine oil pressure monitor lights Defective tightening of oil pipe ( Check, repair)
up joint, oil leakage from damaged
part
Defective engine oil pressure ( Replace sensor)
sensor
Defective monitor ( Replace monitor)
Cooling water level low, water Add cooling water, repair, see
leakage CHECK BEFORE STARTING
Loosen fan belt Replace fan belt
Steam is emitted from top part of
Check tension
radiator (pressure valve)
Dirt or scale accumulated in Change cooling water, clean
cooling system inside of cooling system, see
WHEN REQUIRED
Clogged radiator fin or damaged Clean or repair, see EVERY 500
fin HOURS SERVICE
Defective thermostat ( Replace thermostat)
Radiator water level monitor lights Loose radiator filler cap (high Tighten cap or replace packing
up altitude operation)
Defective water level sensor ( Replace sensor)
Defective monitor ( Replace monitor)
Lack of fuel Add fuel, see CHECK BEFORE
STARTING
Air in fuel system Repair place where air is sucked
in. See EVERY 500 HOURS
SERVICE.
Defective fuel injection pump or ( Replace pump or nozzle)
Engine does not start even when nozzle
starting motor is turned Starting motor cranks engine too See ELECTRICAL SYSTEM
slowly
Preheating monitor does not light See ELECTRICAL SYSTEM
up
defective compression
Defective valve clearance ( Adjust valve clearance)
Password setting is wrong ( Input correct password)
Excessive oil in il pan Add oil to specified level. See
Exhaust gas is white or blue CHECK BEFORE STARTING.
Improper fuel Replace with specified fuel
Clogged air cleaner element Clean or replace. See WHEN
REQUIRED.
Exhaust gas is black Defective nozzle ( Replace nozzle)
Defective compression ( See "Defective pressure" above)
Defective turbocharger Wash or replace turbocharger
There is sometimes breathing in Defective nozzle ( Defective nozzle)
combustion sound

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TROUBLES AND ACTIONS OPERATION

Problem Main causes Remedy

Poor quality fuel being used Replace with specified fuel
Overheating See "Radiator water level
Abnormal noise is generated
monitor lights up" above
(combustion or mechanical)
Breakage inside muffler Replace muffler
Excessive valve clearance ( Adjust valve clearance)

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OPERATION TROUBLES AND ACTIONS

Electronic Control System

If an error code appears on the machine monitor display (normally displays TIME), follow the countermeasure table
as shown below in the self-diagnosis.

Machine Monitoring System

Monitor
Failure mode Remedy
display
When emergency pump drive switch is up, normal operations
E02 Error in pump control system
become normal, but carry out inspection immediately. (*)
Turn the swing holding brake release switch is up to release the
brake. When applying the swing brake, operate it manually with
E03 Swing brake system error the swing lock switch. Depending on the cause of the problem, it
may not be possible to release it. In any case, have it inspected
immediately.(*)
Abnormality in electronic
E10 governor system Carry out inspection immediately.
(engine stopped)
Abnormality in electronic
governor system It is possible to carry out normal working operations, but have
E11
(abnormality in engine inspection carried out immediately.
protection output)
Abnormality in throttle
Move machine to a safe posture, and carry out inspection
E14 (abnormality in fuel control
immediately.
dial)
Abnormality in electronic It is possible to carry out normal driving operations, but have
E15
governor system inspection carried out immediately.
If the engine can be operated, set the machine to a safe
posture, then have inspection carried out immediately.
If the engine is operated and stalls, turn the emergency pump
E04 Abnormality in network drive switch is up set the machine to a safe posture, then have
inspection carried out immediately.
Even if the engine is stopped, have inspection carried out
immediately.
If no error code is displayed but work
Carry out inspection immediately.
equipment or swing cannot be operated

(*): For details of handling the emergency pump drive switch and swing holding brake cancel switch, see
"SWITCHES (PAGE 3-30)".

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TROUBLES AND ACTIONS OPERATION

Point of Contact to Telephone when Error Occurs

If an error screen is displayed on the monitor, the screen changes
as follows each time input confirmation switch (1) is pressed.
Error screen -> screen A -> screen B -> screen C -> error screen
Check the point of contact telephone number on screen B.

REMARK
If the point of contact telephone number has not been registered,
screen B is not displayed.
If it is necessary to register the point of contact telephone number,
ask your Komatsu distributor to register it.

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.

4-1
.

MAINTENANCE INFORMATION MAINTENANCE

MAINTENANCE INFORMATION
Do not perform any inspection and maintenance operation that is not found in this manual.

Service Meter Reading

Check the service meter reading every day to see if the time has come for any necessary maintenance to be
performed.

Komatsu Genuine Replacement Parts

Use Komatsu genuine parts specified in the Parts Book as replacement parts.

Komatsu Genuine Lubricants

Use Komatsu genuine oils and grease. Choose oils and grease with proper viscosities specified for ambient
temperature.

Windshield Washer Fluid

Use automobile window washer fluid, and be careful not to let any dirt get into it.

Fresh and 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.

Check Drained Oil and Used Filter

After oil is changed or filters are replaced, 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 carry out
suitable action.

Fuel Strainer
If your machine is equipped with a fuel strainer, do not remove it while fueling.

Welding Instructions
Turn off the engine starting switch.
Do not apply more than 200 V continuously.
Connect grounding cable within 1 m (3.3 ft) of the area to be welded. If grounding cable is connected near
instruments, connectors, etc., the instruments may malfunction.
If a seal or bearing happens to come between the part being welded and grounding point, change the grounding
point to avoid such parts.
Do not use the area around the work equipment pins or the hydraulic cylinders as the grounding point.

Do not Drop Things Inside Machine

When opening inspection windows or the oil filler port of the tank to carry out 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 you drop anything inside the machine, always remove it immediately.
Do not put unnecessary things in your pockets. Carry only things which are necessary for inspection.

Dusty Jobsite
When working at dusty worksites, do as follows:
Inspect the air cleaner clogging monitor frequently to see if the air cleaner is clogged.
Clean the radiator core frequently to avoid clogging.
Clean and replace the fuel filter frequently.

4-2
.

MAINTENANCE MAINTENANCE INFORMATION

Clean electrical components, especially the starting motor and alternator, to avoid accumulation of dust.
When inspecting or changing the oil, move the machine to a place that is free of dust to prevent dirt from getting
into the oil.

Avoid Mixing Lubricants

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. Never mix different brand or grade of oil.

Locking the Inspection Covers

Lock inspection cover securely into position with the lock bar. If inspection or maintenance is performed with
inspection cover not locked in position, there is a danger that it may be suddenly blow shut by the wind and cause
injury to the worker.

Hydraulic System - Air Bleeding

When hydraulic equipment has been repaired or replaced, or the hydraulic piping has been removed and installed
again, the air must be bled from the circuit. For details, see "BLEEDING AIR FROM HYDRAULIC SYSTEM (PAGE
4-40)".

Hydraulic Hose Installation

When removing parts at locations where there are O-rings or gasket seals, clean the mounting surface, and
replace with new parts.
When doing this, be careful not to forget to assemble the 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 shortened extremely and they may be damaged.

Checks After Inspection and Maintenance Works

If you forget to perform the checks after inspection and maintenance, unexpected problems may occur, and this may
lead to serious injury or property damage. Always do 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 when operating engine
For details of the checks when operating the engine, see "TWO WORKERS FOR MAINTENANCE WHEN
ENGINE IS RUNNING (PAGE 2-35)" and pay careful attention to safety.
Are the inspection and maintenance items working properly?
Is there any leakage of fuel or oil when the engine speed is raised?

4-3
.

OUTLINE OF SERVICE MAINTENANCE

OUTLINE OF SERVICE
HANDLING OIL, FUEL, COOLANT, AND PERFORMING 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 the
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 problems 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 problems.
If the oil in the work equipment is not clear, there is probably water or air getting into the circuit. In such cases,
please contact your Komatsu distributor.
When changing the oil, always replace the related filters at the same time.
We recommend you have an analysis made of the oil periodically to check the condition of the machine. For
those who wish to use this service, please contact your Komatsu distributor.
When using commercially available oil, it may be necessary to shorten the oil change interval.
For this reason, we recommend making full use of the Komatsu oil clinic.

Fuel
To prevent the moisture in the air from condensing and forming water inside the fuel tank, always fill the fuel tank
after completing the day's work.
The fuel pump is a precision instrument, 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 in the Operation and Maintenance Manual.
If the fuel is used at temperatures lower than the specified temperature (particularly at temperatures 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 this may
result in problems such as a drop in output.
Before starting the engine, or when 10 minutes have passed after adding fuel, drain the sediment and water from
the fuel tank.
If the engine runs out of fuel, or if the filters have been replaced, it is necessary to bleed the air from the circuit.

4-4
.

MAINTENANCE OUTLINE OF SERVICE

Cooling System Coolant

River water contains large amount of calcium and other impurities, so if it is used, scale will stick to the engine and
radiator, and this will cause defective heat exchange and overheating.
Do not use water that is not suitable for drinking.
When using antifreeze, always observe the precautions given in the Operation and Maintenance Manual.
Komatsu machines are supplied with Komatsu original anti-freeze in the coolant when the machine is shipped.
This anti-freeze is effective in preventing corrosion of the cooling system.
The anti-freeze can be used continuously for two years or 4000 hours. Therefore, it can be used as it is even in
hot areas.
Antifreeze is flammable, so be extremely careful not to expose it to flame or fire.
The proportion of anti-freeze to water differs according to the ambient temperature.
For details of the mixing proportions, see "CLEAN INSIDE OF COOLING SYSTEM (PAGE 4-24)".
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.

Grease
Grease is used to prevent seizure and noises at the joints.
This construction equipment is used under heavy-duty conditions. Always use the recommended grease and
follow the change intervals and recommended ambient temperatures given in this Operation and Maintenance
Manual.
The nipples not included in the maintenance section are nipples 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.

4-5
.

OUTLINE OF SERVICE MAINTENANCE

Carrying Out KOWA (Komatsu Oil Wear Analysis)

The oil clinic samples the oil periodically and analyzes it. This is a preventive maintenance service, which provides
early discovery of abnormal parts and wear of the drive parts of the machine. This then makes it possible to ensure
prevention of failures and reduction in downtime.
Komatsu's long years of experience and rich supply of accumulated data make it possible to accurately determine
the condition of your machine. This enables us to locate the problems and to recommend suitable and timely repair
methods.
The oil clinic charges the customer only the actual costs, and provides an immediate report of the results of the
analysis and recommendations for action to take. This low-cost service can save you high costs and inconvenience
in the future, so we strongly recommend you to avail yourself of this service.

KOWA Analysis Items

Measurement of density of metal wear particles
This uses an ICP (Inductively Coupled Plasma) analyzer to
measure the density of iron, copper, and other metal wear
particles in the oil.

Measurement of quantity of particles

This uses a particle quantifier index measurement machine to
measure the quantity of iron particles of 5µ or more, enabling
early detection of failures.

Others
Measurements are made of items such as the ratio of water in the oil, density of the antifreeze coolant, ratio of
fuel in the oil, and dynamic viscosity, enabling a highly precise diagnosis of the machine's health.

Oil Sampling
Sampling interval
250 hours: Engine
500 hours: Other components

Precautions when sampling

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, please contact your Komatsu distributor.

4-6
.

MAINTENANCE OUTLINE OF SERVICE

Oil and Fuel Storage

Keep indoors to prevent any water, dirt, or other impurities from getting in.
When keeping drum cans for a long period, put the drum on its side so that the filler port of the drums is at the side
to prevent moisture from being sucked in.
If drums have to be stored outside, cover 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).

Filters
Filters are extremely important safety parts. They prevent impurities in the fuel and air circuits from entering
important equipment and causing problems.
Replace all filters periodically. For details, see the 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 the filters (cartridge type) and use them again. Always replace with new filters.
When replacing oil filters, check if any metal particles are attached to the old filter. If any metal particles are found,
contact your Komatsu distributor.
Do not open packs of spare filters until just before they are to be used.
Always use Komatsu genuine filters.

ELECTRIC SYSTEM MAINTENANCE

It is extremely dangerous if the electrical equipment becomes wet or the covering of the wiring is damaged. This
will cause an electrical short circuit 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.
Service relating to the electric system is checking fan belt tension, checking damage or wear to the fan belt and
checking battery fluid level.
Never install any electric components other than those specified by Komatsu.
External electro-magnetic interference may cause malfunction of the control system controller, before installing
a radio receiver or other wireless equipment, contact your Komatsu distributor.
When working at the seashore, carefully clean the electric system to prevent corrosion.
When installing electrical equipment, connect it to the special power source connector.
Do not connect the optional power source to the fuse, starting switch, or battery relay.

4-7
.

WEAR PARTS MAINTENANCE

WEAR PARTS
Replace wear parts such as the filter element or air cleaner element at the time of periodic maintenance or before
they reach the wear limit. The wear parts should be replaced correctly in order to ensure more economic use of the
machine. When replacing parts, always use Komatsu genuine parts.
As a result of our continuous efforts to improve product quality, the part number may change, so inform your
Komatsu distributor of the machine serial number and check for the latest part number when ordering parts.

WEAR PARTS LIST

The parts in parentheses are to be replaced at the same time.

Item Part No. Part Name Q'ty Change interval

Engine oil filter 600-211-1340 Cartridge 1 Every 500 hours
Every 500 hours
(Without additional fuel filter)
Fuel filter 600-319-3520 Cartridge 1
Every 1000 hours
(With additional fuel filter)
Additional fuel filter 600-319-3440 Cartridge 1 Every 500 hours
Hydraulic tank breather 20Y-60-21470 Element 1 Every 500 hours
Additional breather for
421-60-35170 Element 1 Every 1000 hours
hydraulic tank
Corrosion resistor 600-411-1571 Cartridge 1 Every 1000 hours
208-60-71122 Element 1
Hydraulic oil filter Every 1000 hours
(07000-15210) (O-ring) (1)
Air conditioner RECIRC filter 20Y-979-6261 Filter Every one year
Air conditioner FRESH filter 17M-911-3530 Element Every one year
Element assembly
Air cleaner 600-185-6100 1 -
(Outer, Inner, O-ring)
207-970-5121 Element 1
Additional filter for breaker
(07000-12011) (O-ring) (1) -
(if equipped)
(07000-02125) (O-ring) (1)

Electric heater 6150-11-4821 Gasket 2 -

Line filter 207-60-61250 Element 2

-
(if equipped) (07002-13634) (O-ring) (2)
Vertical pin type
208-70-34211 Tooth 5
(208-70-34200) (Pin) (5)
Horizontal pin type
208-70-14152 Tooth 5
Side cutter type
Bucket 208-70-34160 cutter (left) 1 -
208-70-34170 cutter (right) 1
Shroud type
208-934-7130 Shroud 4
113-78-21170 Pin 8
209-939-7110 Shim 16
209-939-7120 Shim 8

4-8
.

MAINTENANCE LUBRICANTS, FUEL AND COOLANT SPECIFICATIONS

LUBRICANTS, FUEL AND COOLANT SPECIFICATIONS

*1: ASTM D975 No.1

NOTICE
Use only diesel fuel.
The engine mounted on this machine employs electronic control and a high-pressure fuel injection device to obtain good fuel
consumption and good exhaust gas characteristics. For this reason, it requires high precision for the parts and good lubrication.
If kerosene or other fuel with low lubricating ability is used, there will be a big drop in durability.

4-9
.

LUBRICANTS, FUEL AND COOLANT SPECIFICATIONS MAINTENANCE

Swing Final drive

Engine Damper Hydraulic Cooling Fuel
machinery case
oil pan case oil system system tank
case (Each)
Specified Liter 42 20 12 1.07 472 36 650
capacity US gal 11.10 5.28 3.17 0.28 124.70 9.51 171.73
Refill Liter 38 20 12 1.07 248 36 -
capacity US gal 10.04 5.28 3.17 0.28 65.2 9.51 -
REMARK
When fuel sulphur content is less than 0.5%, change oil in the oil pan according to the periodic maintenance
hours described in this manual.
Change oil according to the following table if fuel sulfur content is above 0.5%.

When starting the engine with an atmospheric temperature of lower than 0°C (32°F), be sure to use engine oil
of SAE10W, SAE10W-30 and SAE15W-40, even though the atmospheric temperature goes up to 10°C (50°
F) more or less during the day.

Use API classification CD as engine oil and if API classification CC, reduce the engine oil change interval to half.

There is no problem if single grade oil is mixed with multigrade oil (SAE10W-30, 15W-40), but be sure to add
single grade oil that matches the temperature range in the table.

We recommend Komatsu genuine oil which has been specifically formulated and approved for use in engine and
hydraulic work equipment applications.

Specified capacity: Total amount of oil including oil for components and oil in piping.

Refill capacity: Amount of oil needed to refill system during normal inspection and maintenance.

ASTM: American Society of Testing and Material

SAE: Society of Automotive Engineers
API: American Petroleum Institute

Fuel sulfur content Engine oil change interval

0.5 to 1.0% 1/2 of regular interval
Above 1.0% 1/4 of regular interval

4 - 10
.

MAINTENANCE LUBRICANTS, FUEL AND COOLANT SPECIFICATIONS

Engine Oil
Anti-freeze
[CD or CE]
Gear Oil Grease Coolant
SAE10W, 30, 40
No. Supplier [GL-4 or GL-5] [Lithium-Base] [Ethylene Glycol
10W30, 15W40
SAE80, 90, 140 NLGI No.2 Base]
(The 15W40 oil
Permanent Type
marked * is CE.)
EO10-CD AF-ACL
EO30-CD GO90 G2-LI AF-PTL
1 KOMATSU
EO10-30CD GO140 G2-LI-S AF-PT(Winter, one
EO15-40CD season type)
Diesel sigma S
super dieselmulti-
2 AGIP Rotra MP GR MU/EP -
grade
*Sigma turbo
Multi-purpose gear PYKON premium
3 AMOCO *Amoco 300 -
oil grease
Litholine HEP 2
4 ARCO *Arcofleet S3 pius Arco HD gear oil -
Arco EP moly D
Gear oil EP
5 BP Vanellus C3 Energrease LS-EP2 Antifreeze
Hypogear EP
*RPM delo 400 Universal thuban Marfak all purpose 2
6 CALTEX AF engine coolant
RPM delo 450 Universal thuban EP Ultra-duty grease 2
EP
*Turbomax EPX
MS3
7 CASTROL *RX super Hypoy Anti-freeze
Spheerol EPL2
CRD Hypoy B
Hypoy C
8 CHEVRON *Delo 400 Universal gear Ultra-duty grease 2 -
Universal gear
9 CONOCO *Fleet motor oil Super-sta grease -
lubricant
Multiperformance 3C Tranself EP
10 ELF - Glacelf
Performance 3C Tranself EP type 2
Essolube D3
*Essolube XD-3
EXXON Gear oil GP
11 *Essolube XD-3 Extra Beacon EP2 All season coolant
(ESSO) Gear oil GX
*Esso heavy duty
Exxon heavy duty
Super duty motor oil Multi-purpose gear Gulfcrown EP2 Antifeeze and
12 GULF
*Super duty plus lubricant Gulfcrown EP special coolant
Delvac 1300 Mobilux EP2
Mobilube GX
13 MOBIL *Delvac super Mobilgease 77 -
Mobilube HD
10W-30, 15W-40 Mobilgrease special

4 - 11
.

LUBRICANTS, FUEL AND COOLANT SPECIFICATIONS MAINTENANCE

Engine Oil
Anti-freeze
[CD or CE]
Gear Oil Grease Coolant
SAE10W, 30, 40
No. Supplier [GL-4 or GL-5] [Lithium-Base] [Ethylene Glycol
10W30, 15W40
SAE80, 90, 140 NLGI No.2 Base]
(The 15W40 oil
Permanent Type
marked * is CE.)
Multi-purpose white
*Supreme duty Multi-purpose 4092 grease 705 Anti-freeze and
14 PENNZOIL
fleet motor oil Multi-purpose 4140 707L White-bearing summer coolant
grease
PETROFIN FINA potonic N
15 FINA kappa TD FINA marson EPL2 FINA tamidor
A FINA potonic NE
Spirax EP
16 SHELL Rimura X Albania EP grease -
Spirax heavy duty
Sunoco ultra prestige Sunoco antifreeze
Sunoco GL5
17 SUN - 2EP and summer
gear oil
Sun prestige 742 coolant
*Ursa super plus Multifak EP2 Coda 2055 startex
18 TEXACO Multigear
Ursa premium Starplex 2 antifreeze coolant
Total EP
Rubia S
19 TOTAL Total Transmission Multis EP2 Antigal/antifreeze
*Rubia X
TM
20 UNION *Guardol MP gear lube LS Unoba EP -
*Turbostar Multigear
21 VEEDOL *Diesel star Multigear B - Antifreeze
MDC Multigear C

4 - 12
.

MAINTENANCE TIGHTENING TORQUE SPECIFICATIONS

TIGHTENING TORQUE SPECIFICATIONS

TIGHTENING TORQUE LIST
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 pay careful attention 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, always use a Komatsu genuine part of the same size as the part that was
replaced.

Thread Width Tightening torque

diameter across
Target value Service limit
of bolt flats
(a)(mm) (b)(mm) N·m kgf·m lbft N·m kgf·m lbft

6 10 13.2 1.35 9.8 11.8-14.7 1.2-1.5 8.7-10.8

8 13 31 3.2 23.1 27-34 2.8-3.5 20.3-25.3
10 17 66 6.7 48.5 59-74 6.0-7.5 43.4-54.2
12 19 113 11.5 83.2 98-123 10.0-12.5 72.3-90.4
14 22 172 17.5 126.6 153-190 15.5-19.5 112.1-141

16 24 260 26.5 191.7 235-285 23.5-29.5 170.0-213.4

18 27 360 37 267.6 320-400 33.0-41.0 238.7-296.6
20 30 510 52.3 378.3 455-565 46.5-58.0 336.3-419.5
22 32 688 70.3 508.5 610-765 62.5-78.0 452.1-564.2
24 36 883 90 651 785-980 80.0-100.0 578.6-723.3

27 41 1295 132.5 958.4 1150-1440 118.0-147.0 853.5-1063.3

30 46 1720 175.0 1265.8 1520-1910 155.0-195.0 1121.1-1410.4
33 50 2210 225.0 1627.4 1960-2450 200.0-250.0 1446.6-1808.3
36 55 2750 280.0 2025.2 2450-3040 250.0-310.0 1808.3-2242.2
39 60 3280 335.0 2423.1 2890-3630 295.0-370.0 2133.7-2676.2

Apply the following table for Hydraulic Hose.

Width Tightening torque [N·m (kgf·m)]

Thread
across
diameter a Target
flat Permissible range
(mm) value
b(mm)
9/16 -18UNF 19 44 (4.5) 35 - 54 (3.5 - 5.5)
11/16 -16UN 22 74 (7.5) 54 - 93 (5.5 - 9.5)
13/16 -16UN 27 103 (10.5) 84 - 132 (8.5 - 13.5)
1 -14UNS 32 157 (16.0) 128 - 186 (13.0 - 19.0)
1·3/16 -12UN 36 216 (22.0) 177 - 245 (18.0 - 25.0)
*1-7/16-12UN
41 215 (22) 176 - 234 (18 - 24)
-2B

The torques marked * indicate the tightening torques for the hoses at the top of the swivel joint.

4 - 13
.

SAFETY CRITICAL PARTS MAINTENANCE

SAFETY CRITICAL PARTS

For using the machine safely for an extended period of time, you are required to periodically replace the safety
(critical and fire prevention) related parts listed in the table of important parts on the following page.
Material quality of these parts can change as time passes and they are likely to wear out or deteriorate. However,
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 important 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 to be replaced periodically. Tighten all loose
clamps 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 critical parts.

SAFETY CRITICAL PARTS LIST

No Safety critical part Q'ty Replacement interval
1 Fuel return hose (engine to fuel cooler) 1
2 Fuel cooler to fuel tank 1
3 Fuel hose (fuel tank to fuel strainer) 1
4 Fuel strainer to engine or additional fuel filter 1
5 Spill hose (nozzle to fuel tank) 1
6 Spill hose (between nozzles) 5
7 Fuel hose (fuel filter to injection pump) 1
8 Fuel hose 1
9 Pump outlet hose (pump to control valve) 2
10 Work equipment hose (boom cylinder inlet port) 4
Work equipment hose
11 2
(bucket cylinder line, boom foot portion)
12 Work equipment hose (bucket cylinder inlet port) 2 Every two years or 4000
Work equipment hose hours, whichever comes sooner
13 2
(bucket cylinder inlet port 4.0 m (13 ft 1 in) arm)
14 Work equipment hose (arm cylinder line, boom foot portion) 2
15 Work equipment hose (arm cylinder inlet port) 2
16 Attachment additional line hose (boom foot portion) 2
17 Attachment additional line hose (boom intermediate portion) 2
18 Attachment additional line hose (boom top portion) 2
19 Swing line hose (swing motor inlet port) 2
20 Main suction hose 1
21 Gear pump suction hose 1
22 Heater hose 2
23 Travel line hose (control valve to swivel joint) 4
24 Travel line hose (swivel joint to travel motor) 4
25 Seat belt 1 Replace every three years

4 - 14
.

MAINTENANCE MAINTENANCE SCHEDULE

MAINTENANCE SCHEDULE
If the machine is equipped with a hydraulic breaker, the maintenance schedule for some parts will be different. For
details, see "MAINTENANCE INTERVAL FOR HYDRAULIC BREAKER (PAGE 4-17)" to confirm the correct
maintenance schedule when carrying out maintenance.

MAINTENANCE SCHEDULE CHART

INITIAL 250 HOURS MAINTENANCE (ONLY AFTER THE FIRST 250 HOURS)
REPLACE FUEL FILTER CARTRIDGE 4- 55

INITIAL 1000 HOURS MAINTENANCE (ONLY AFTER THE FIRST 1000 HOURS)
CHECK ENGINE VALVE CLEARANCE, ADJUST 4- 75

WHEN REQUIRED
CHECK, CLEAN AND REPLACE AIR CREANER ELEMENT 4- 19
CLEAN INSIDE OF COOLING SYSTEM 4- 24
CHECK AND TIGHTEN TRACK SHOE BOLTS 4- 26
CHECK AND ADJUST TRACK TENSION 4- 27
CHECK ELECTRICAL INTAKE AIR HEATER 4- 28
REPLACE BUCKET TEETH (VERTICAL PIN TYPE) 4- 29
REPLACE BUCKET TEETH (HORIZONTAL PIN TYPE) 4- 32
REPLACE BUCKET SIDE CUTTER, SHROUD 4- 33
ADJUST BUCKET CREARANCE 4- 34
CHECK WINDOW WASHER FLUID LEVEL, ADD FLUID 4- 35
CHECK AND ADJUST AIR CONDITIONER 4- 36
WASH WASHABLE FLOOR 4- 37
BLEEDING AIR FROM HYDRAULIC SYSTEM 4- 40
METHOD FOR RELEASING INTERNAL PRESSURE IN HYDRAULIC CIRCUIT 4- 42
CHECK NITROGEN GAS CHARGE PRESSURE IN ACCUMULATOR (CONTROL CIRCUIT) 4- 43

CHECKS BEFORE STARTING

EVERY 50 HOURS MAINTENANCE

LUBRICATING 4- 45

EVERY 250 HOURS MAINTENANCE

CHECK OIL LEVEL IN SWING MACHINERY CASE, ADD OIL 4- 46
CHECK OIL LEVEL IN FINAL DRIVE CASE, ADD OIL 4- 47
CHECK LEVEL OF BATTERY ELECTROLYTE 4- 48
LUBRICATE SWING CIRCLE (2 POINTS) 4- 51
CHECK FAN BELT, ALTERNATOR BELT TENSION, ADJUST 4- 51
CHECK AIR CONDITIONER COMPRESSOR BELT TENSION, ADJUST 4- 52

EVERY 500 HOURS MAINTENANCE

LUBRICATING 4- 53
REPLACE FUEL FILTER CARTRIDGE (MACHINES EQUIPPED WITHOUT ADDITIONAL FUEL
FILTER CARTRIDGE) 4- 55
CHECK, WASH FUEL STRAINER 4- 57
CHECK SWING PINION GREASE LEVEL, ADD GREASE 4- 58
CHANGE OIL IN ENGINE OIL PAN, REPLACE ENGINE OIL FILTER CARTRIDGE 4- 59

4 - 15
.

MAINTENANCE SCHEDULE MAINTENANCE

CLEAN AND INSPECT RADIATOR FINS, OIL COOLER FINS, AFTER COOLER FINS, FUEL
COOLER FINS, AND CONDENSER FINS (only machines equipped with air conditioner) 4- 61
CLEAN AIR CONDITIONER FRESH/RECIRC FILTERS 4- 62
REPLACE BREATHER ELEMENT IN HYDRAULIC TANK 4- 63
REPLACE ADDITIONAL FUEL FILTER CARTRIDGE (IF EQUIPPED WITH MACHINES) 4- 64

EVERY 1000 HOURS MAINTENANCE

REPLACE FUEL FILTER CARTRIDGE (MACHINES EQUIPPED WITH ADDITIONAL FUEL FILTER
CARTRIDGE) 4- 66
REPLACE HYDRAULIC OIL FILTER ELEMENT 4- 68
CHANGE OIL IN SWING MACHINERY CASE 4- 69
CHECK OIL LEVEL IN DAMPER CASE, ADD OIL 4- 70
CHECK ALL TIGHTENING PARTS OF TURBOCHARGER 4- 70
CHECK PLAY TURBOCHARGER ROTOR 4- 70
REPLACE CORROSION RESISTOR CARTRIDGE 4- 71
REPLACE HYDRAULIC TANK ADDITIONAL BREATHER ELEMENT 4- 72
CHECK NITROGEN GAS CHARGE PRESSURE IN ACCUMULATOR (FOR BREAKER) 4- 72

EVERY 2000 HOURS MAINTENANCE

CHANGE OIL IN FINAL DRIVE CASE 4- 73
CHECK INJECTOR 4- 73
CLEAN HYDRAULIC TANK STRAINER 4- 74
CLEAN ENGINE BREATHER 4- 74
CLEAN, CHECK TURBOCHARGER 4- 75
CHECK ALTERNATOR, STARTING MOTOR 4- 75
CHECK ENGINE VALVE CLEARANCE, ADJUST 4- 75
CHECK VIBRATION DAMPER 4- 75

EVERY 4000 HOURS MAINTENANCE

CHECK WATER PUMP 4- 76
CHECK FOR LOOSENESS OF HIGH-PRESSURE PIPING CLAMP, HARDENING OF RUBBER 4- 76
CHECK FOR MISSING FUEL SPRAY PREVENTION CAP, HARDENING OF RUBBER 4- 77
REPLACE INJECTOR NOZZLE ASSEMBLY 4- 77

EVERY 5000 HOURS MAINTENANCE

CHANGE OIL IN HYDRAULIC TANK 4- 78

EVERY 8000 HOURS MAINTENANCE

REPLACE HIGH-PRESSURE PIPING CLAMP 4- 80
REPLACE FUEL SPRAY PREVENTION CAP 4- 80

4 - 16
.

MAINTENANCE MAINTENANCE SCHEDULE

MAINTENANCE INTERVAL FOR HYDRAULIC BREAKER

For machine equipped with a hydraulic breaker, the hydraulic oil deteriorates faster than for normal bucket digging
operations, so set the maintenance intervals as follows.

REPLACE HYDRAULIC OIL FILTER ELEMENT

On new machines, replace the element after the first 100 to 150
hours, then carry out further replacement of the element
according to the table on the right.

CHANGE OIL IN HYDRAULIC TANK

Change the oil according to the table on the right.

REPLACE ADDITIONAL FILTER ELEMENT FOR BREAKER

Use a guideline of 250 hours for use of the breaker (operating ratio for the breaker: 50 % or more), and replace
the element according to the table on the right.

4 - 17
.

MAINTENANCE PROCEDURE MAINTENANCE

MAINTENANCE PROCEDURE
INITIAL 250 HOURS MAINTENANCE (ONLY AFTER THE FIRST 250 HOURS)
Carry out the following maintenance only after the first 250 hours of operation on new machines.
Replace fuel filter cartridge
Special tools are needed for the inspection and maintenance, so please contact your Komatsu distributor to have
this work carried out.
For details of the method of replacing or maintaining, see the section on EVERY 500 HOURS SERVICE.

INITIAL 1000 HOURS MAINTENANCE (ONLY AFTER THE FIRST 1000 HOURS)
Carry out the following maintenance only after the first 1000 hours of operation on new machines.
Check engine valve clearance, adjust
Special tools are needed for inspection and maintenance, so contact your Komatsu distributor.
For details of the method of replacing or maintaining, see the section on EVERY 2000 HOURS SERVICE.

4 - 18
.

MAINTENANCE MAINTENANCE PROCEDURE

WHEN REQUIRED

CHECK, CLEAN AND REPLACE AIR CLEANER ELEMENT

WARNING
When using compressed air, there is danger of dirt flying and causing personal injury.
Always wear protective glasses, dust mask, or other protective equipment.
When removing the outer element from the air cleaner body, it is dangerous to pull it out by force. When working in high places
or where the foothold is poor, be careful not to fall because of the reaction when pulling out the outer element.

Checking
If air cleaner clogging monitor (1) of the monitor panel flashes,
clean the air cleaner element.

Replacing
Replacing element, O-ring
If one year has passed since installing the element or if air
cleaner clogging monitor (1) on the monitor panel flashes
immediately after the element is cleaned, replace the outer
element, inner element, and O-ring.
Replacing evacuator valve
Replace it if it is damaged or the rubber is markedly deformed.
NOTICE
Do not clean the air cleaner element until the air cleaner clogging monitor on the monitor panel light up. If the element is
cleaned frequently before the air cleaner clogging monitor light up, the air cleaner will not be able to display its performance
fully, and the cleaning efficiency will also go down.
In addition, during the cleaning operation, more dirt stuck to the element will fall inside the inner element.
If inspection, cleaning, or maintenance is carried out with the engine running, dirt will enter the engine and cause damage to
the engine. Always stop the engine before carrying out these operations.

Cleaning Outer Element

1. Open the engine hood at the front side of the machine, remove
6 hooks (2), then remove cover (3).

NOTICE
Before and after cleaning the element, do not leave or keep it in direct
sunlight.

2. Hold the outer element, rock it lightly up and down and to the left and right, and rotate the element to the left and
right to pull it out.

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MAINTENANCE PROCEDURE MAINTENANCE

NOTICE
Never remove the inner element (6). It will allow dirt to enter and cause
failure of the engine.
Do not use a screwdriver or other tool.

3. After removing the outer element (5), cover the inner element
(6) with a clean cloth or tape to prevent dirt or dust from
entering.

4. Wipe off or brush off the dirt stuck to cover (3) and the inside of
the air cleaner body (7).

5. Remove any dirt or dust that is accumulated to evacuator valve

(4) installed to cover (3).

6. Direct dry compressed air (less than 0.69 MPa (7 kgf/cm2, 99.4
PSI)) to the outer element from inside along its folds, then
direct it from outside along its folds and again from inside.
1) Remove one seal from the element whenever the element
has been cleaned.
2) Replace the outer element which has been cleaned 6
times repeatedly or used throughout a year. Replace the
inner element at the same time.

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MAINTENANCE MAINTENANCE PROCEDURE

3) Replace both inner and outer elements when the air cleaner clogging monitor (1) lights up soon after
installing the cleaned outer element even though it has not been cleaned 6 times.
4) When replacing the element, stick on seal (A) packed in
the same box as the element. Stick the seal in the position
shown in the diagram on the right.

7. Remove the cloth or tape cover installed in Step 3.

8. If small holes or thinner parts are found on the element when
it is checked by shining a light through it after cleaning, replace
the element.

NOTICE
When cleaning the element, do not hit or beat it against anything.
Do not use an element whose folds or gasket or seal are damaged.

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MAINTENANCE PROCEDURE MAINTENANCE

Install Air Cleaner Element

NOTICE
Do not use any damaged gasket or seal or element with damaged pleats.
Cleaning the element or O-ring after one year has passed and using them again will cause problems. Always replace them with
new parts.
The seal portion on imitation parts lacks precision, and allows the entry of dust, which leads to damage of the engine. Do not
use such imitation parts.
Do not run the engine with the inner element removed. It will cause damage to the engine.

1. Check that there is no dirt or oil stuck to the seal portion of the new element or cleaned element. Wipe off any
dirt or oil.
2. When the outer element has been removed, check that the inner element has not come out of position and is
not at an angle. If inner element is at an angle, insert your hand and push it in straight.
3. Push the outer element in straight with your hand when installing it to the air cleaner body.
If the outer element is held and rocked lightly up and down and to the left and right while pushing it in, the outer
element can be inserted easily.

NOTICE
When inserting the element, if the rubber at the tip is swollen or the outer element is not pushed in straight, and cover (3) is
assembled by force to hook (2), there is danger that the hook and air cleaner body may be damaged, so be careful when
assembling.
4. Install cover (3) as follows.
1) Align cover (3) with the element.
2) Hook the tip of hook (2) to the protruding part of the air
cleaner body and lock it in position.
3) When locking hooks (2) in position, apply the hooks in turn
on opposite sides (top, bottom, left, right) in the same way
as when tightening bolts.
4) Always install cover (3) so that the evacuator (4) is facing
the ground (A).
5) When cover (3) is installed, check that the clearance
between the air cleaner body and cover (3) is not too large.
If it is too large, install again.

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MAINTENANCE MAINTENANCE PROCEDURE

Replacing Inner Element

1. First remove the outer element, and then remove the inner element.
2. Cover the air connector side (outlet side) with a clean cloth or tape.
3. Clean the air cleaner body interior, then remove the cover from the air intake port in Step 2.
4. Install the new inner element to the connector, then install the outer element.

NOTICE
The inner element must not be used again even after cleaning. When replacing the outer element, replace the inner element at the
same time.

5. Set the outer element in position, then lock cover (3) with hooks
(2).

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MAINTENANCE PROCEDURE MAINTENANCE

CLEAN INSIDE OF COOLING SYSTEM

WARNING
Immediately after the engine is stopped, the coolant is at a high temperature and the radiator is under high internal pressure.
If the cap is removed to drain the coolant in this condition, there is a hazard of burns. Wait for the temperature to go down, then
turn the cap slowly to release the pressure before removing it.
Cleaning is carried out with the engine running. When standing up or leaving the operator's seat, set the lock lever to the LOCK
position.
For details of starting the engine, see"BEFORE STARTING ENGINE (PAGE 3-71)" and "STARTING ENGINE (PAGE 3-86)" in the
OPERATION section.
There is danger of touching the fan if the undercover is left removed.
Never enter behind the machine when the engine is running.

Clean the inside of the cooling system, change the coolant and replace the corrosion resistor according to the table
below.

Cleaning inside of cooling system

Kind of coolant Replacing corrosion resistor
and changing coolant
Every year (autumn) or
Permanent type antifreeze
every 2000 hours,
(All season type)
whichever comes first
Every 1000 hours and when
Non permanent type antifreeze Every 6 months (spring, autumn)
cleaning the inside of the
containing ethylene glycol (Drain antifreeze in spring,
cooling system and
(winter, one season type) add antifreeze in autumn)
when changing coolant
Every 6 months or
When not using antifreeze every 1000 hours,
whichever come first

Stop the machine on level ground when cleaning or changing the coolant.
Use a permanent type of antifreeze.
If, for some reason, it is impossible to use permanent type antifreeze, use an antifreeze containing ethylene glycol.
Super Coolant (AF-ACL) has an anti-corrosion effect as well as an antifreeze effect.
The ratio of antifreeze to water depends on the ambient temperature, but to obtain the corrosion resistance effect,
a minimum ratio of 30% by volume is necessary.
When deciding the ratio of antifreeze to water, check the lowest temperature in the past, and decide from the mixing
rate table given below.
It is actually better to estimate a temperature about 10°C (18°F) lower when deciding the mixing rate.

Mixing rate of water and antifreeze

Min. atmospheric °C Above-10 -15 -20 -25 -30 -35 -40

temperature °F Above14 5 -4 -13 -22 -31 -40
liter 10.8 13.0 14.8 16.6 18.0 19.4 20.1
Amount of antifreeze
US gal 2.85 3.43 3.91 4.39 4.76 5.13 5.31
liter 25.2 23.0 21.2 19.4 18.0 16.6 15.9
Amount of water
US gal 6.66 6.08 5.60 5.12 4.76 4.39 4.20
Volume ratio (%) 30 36 41 46 50 54 58

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MAINTENANCE MAINTENANCE PROCEDURE

WARNING
Antifreeze is flammable, so keep it away from flame.
Antifreeze is toxic. When removing the drain plug, be careful not to get water containing antifreeze on you. If it gets in your eyes,
flush your eyes with large amount of fresh water and see a doctor at once.

Use city water for the coolant.

If river water, well water or other such water supply must be used, contact your Komatsu distributor.
We recommend use of an antifreeze density gauge to control the mixing proportions.
Prepare two containers of a capacity of at least 20 liters (5.28 US gal) to catch the coolant.
1. Stop the engine and tighten corrosion resistor valve (1). (Only
machines equipped with corrosion resistor)
2. Turn radiator cap (2) slowly to release the internal pressure.
3. Push radiator cap (2) in and turn it slowly.

4. Remove the undercover, then set containers to catch the

coolant under drain valves (3) and (4).
Open drain valve (3) at the rear of the machine (right side of
engine block) and drain the water.
Open drain valve (4) under the radiator and drain the water.
5. After draining the antifreeze solution, close drain valves (3) and
(4), then fill with clean water. After the radiator is filled with
water, start and run the engine at low idling speed. After the
water temperature rises above 90 °C (194 °F), run the engine
for about 10 minutes.
6. Stop the engine and open drain valves (3) and (4) to drain the
water.
7. After draining the water, clean the radiator with detergent.
For the cleaning method, follow the instruction of detergent.
8. Close drain valves (3) and (4).
9. Replace the corrosion resistor, and open valve (1).(Only machines equipped with corrosion resistor)
For details of replacement of the corrosion resistor cartridge, see "REPLACE CORROSION RESISTOR
CARTRIDGE (PAGE 4-71)".
10. Install the undercover.
11. Add water through the water filler up to the filler port.
12. Run the engine at low idling for 5 minutes to remove the air from the water, then run at high idling for 5 minutes.
(Leave radiator cap (2) removed when doing this.)

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MAINTENANCE PROCEDURE MAINTENANCE

13. Drain the coolant from sub tank (5), wash the inside of the sub
tank, then add water to between the FULL and LOW marks.
14. Stop the engine, wait for approx. 3 minutes, add city water up
to near the mouth of the filler port, then tighten radiator cap (2).

CHECK AND TIGHTEN TRACK SHOE BOLTS

If the machine is used with track shoe bolts (1) loose, they will
break, so tighten any loose bolts immediately.

Tightening
1. First, tighten to a tightening torque of 392 ± 39.2 N·m (40 ± 4 kgf·m, 289.3 ± 28.9 lbft), then check that the nut
and shoe are in tight contact with the link mating surface.
2. After checking, tighten a further 120° ± 10°.

Order for Tightening

Tighten the bolts in the order shown in the diagram on the right.
After tightening, check that the nut and shoe are in close contact
with the link mating surface.

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MAINTENANCE MAINTENANCE PROCEDURE

CHECK AND ADJUST TRACK TENSION

WARNING
For details on starting the engine and operating the work equipment, see "BEFORE STARTING ENGINE (PAGE 3-71)", "STARTING
ENGINE (PAGE 3-86)", "AFTER STARTING ENGINE (PAGE 3-90)", and "WORK EQUIPMENT CONTROLS AND OPERATIONS (PAGE
3-107)" in the OPERATION section.

Wear on pins and bushings of the undercarriage will vary with working conditions and type of soil, so inspect the
track tension every now and then in order to maintain the standard tension.
For carrying out inspection and adjustment of track shoes, park the machine on the flat and solid ground.

Checking
1. Run the engine at low idle, then move the machine forward for
a distance equal to the track length on ground, and slowly stop
the machine.
2. Put on the track shoe straight wooden bar (3) which stretches
from idler (1) to upper carrier roller (2).
3. Measure the maximum deflection between bottom surface of
the wooden bar and top surface of the track shoe.
Deflection "a" should be 10 - 30 mm (0.4 - 1.2 in).

If the track tension is not at the standard value, adjust it in the following manner.

Adjustment

WARNING
There is danger of plug (1) flying out under the high internal pressure of the
grease. Never loosen plug (1) more than 1 turn.
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 with the procedure given here,
please contact your Komatsu distributor.

Increasing Track Tension

Prepare a grease pump.
1. Pump in grease through grease fitting (2) with a grease pump.
(Grease fitting (2) forms one part with plug (1).)
2. To check if the tension is correct, run the engine at low idle,
move the machine slowly forward (by an amount equal to the
length of track on ground), then stop the machine.
3. Check the track tension again, and if the tension is not correct,
adjust it again.

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MAINTENANCE PROCEDURE MAINTENANCE

4. Continue to pump in grease until dimension (S) becomes zero

(0). If the tension is still loose, the pin and bushing are
excessively worn, so they must be either turned or replaced.
Please contact your Komatsu distributor for repairs.

Loosening Track Tension

WARNING
It is extremely dangerous to release the grease by any method except the procedure given below.
If track tension is not relieved by this procedure, contact your Komatsu distributor for repairs.

1. Loosen plug (1) gradually to release the grease.

2. When loosening plug (1), turn it a maximum of one turn.
3. If the grease does not come out smoothly, move the machine
forwards and backwards a short distance.
4. Tighten plug (1).
5. To check if the tension is correct, run the engine at low idle,
move the machine slowly forward (by an amount equal to the
length of track on ground), then stop the machine.
6. Check the track tension again, and if the tension is not correct,
adjust it again.

CHECK ELECTRICAL INTAKE AIR HEATER

Before the start of the cold season (once a year), contact your Komatsu distributor to have the electrical intake air
heater checked for dirt or disconnections.

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MAINTENANCE MAINTENANCE PROCEDURE

REPLACE BUCKET TEETH (VERTICAL PIN TYPE)

Replace the bucket teeth before the adapter starts to wear.

WARNING
It is dangerous if the work equipment is mistakenly moved when
replacing the teeth.
Set the work equipment in a stable condition, stop the engine, then set
lock lever (1) securely to the LOCK position (L).
As the locking pin is knocked out with force, there is danger that the pin
may fly out. Check that there is no one near the machine.
Broken pieces may fly during the replacement operation, so always
wear safety glasses, gloves, or other protective equipment.

1. To make it possible to knock out pin of tooth (1), put block (5)
under the bottom of the bucket, and set so that the bottom
surface of the bucket is horizontal.

2. Use a hammer and drift to knock out lock pin (2). (If the drift is
set against rubber pin lock (3) when it is hit, the rubber pin lock
may break. Set it against the back of the pin.)
3. After removing lock pin (2) and rubber pin lock (3), check them.
If lock pin (2) and rubber pin lock (3) are used in the condition
below, it will cause tooth (1) to come off during operation.
Always replace them with new parts.

Lock pin (2) is too short.

Dimension (B) is less than 1/3 A when lock pin (2) is aligned at
bottom surface (C).

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MAINTENANCE PROCEDURE MAINTENANCE

Rubber (6) of the rubber pin lock is cut and the steel ball is about
to come out.

Steel ball (7) sinks in when it is pushed by hand.

4. Clean the surface of adapter (4) and remove the soil with a knife.
5. Hit rubber pin lock (3) by hand or with a metal hammer and
push it into the hole in adapter (4).
When doing this, be careful not to let rubber pin lock (3) fly out
from the surface of adapter (4).
6. Clean the inside surface of tooth (1), then install to adapter (4).
If there is any mud stuck to it or any protrusion, tooth (1) will not
fit properly in adapter (4) and the fitting contact will be poor.

7. Fit tooth (1) to adapter (4), and confirm that when the pointer is
pressed strongly, the rear face of the hole for the pin of the
teeth (1) is at the same level as the rear face of the hole for the
pin of the adapter (4).
If the rear face of the pin hole of tooth (1) protrudes in front of
the rear face of the pin hole of adapter (4), do not knock the pin
in.
If this happens, there is something (C) preventing the tooth (1)
from fitting completely in adapter (4), locate the problem and
remove the obstruction. When tooth (1) fits completely in
adapter (4), knock in lock pin (2).

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MAINTENANCE MAINTENANCE PROCEDURE

8. Insert lock pin (2) in the pin hole in the tooth (1), and knock it in
so that the top surface of lock pin (2) is the same height as the
surface of tooth (1).
9. After replacing the bucket tooth, always check as follows.
1) After lock pin (2) is completely knocked in, check that it is
secured in position at tooth (1) and the surface.
2) After knocking in the lock pin (2) from one direction, tap it
back lightly in the opposite direction.
3) Tap the tip of tooth (1) from the top and bottom, and the side
face from the left and right.
4) Rubber pin lock (3) and lock pin (2) must be as shown in the
diagram on the right.

REMARK
If the tooth is turned, the wear will become uniform. This will extend
the service life of the tooth and reduce the frequency of
replacement.
When replacing the tooth, replace the rubber pin lock and lock pin
with new parts at the same time. This will prevent the tooth from
falling out.

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MAINTENANCE PROCEDURE MAINTENANCE

REPLACE BUCKET TEETH (HORIZONTAL PIN TYPE)

Replace the teeth before the wear reaches the adapter.

WARNING
It is dangerous if the work equipment is mistakenly moved when
replacing the teeth.
Set the work equipment in a stable condition, stop the engine, then set
lock lever (1) securely to the LOCK position (L).
As the locking pin is knocked out with force, there is danger that the pin
may fly out. Check that there is no one near the machine.
Broken pieces may fly during the replacement operation, so always
wear safety glasses, gloves, or other protective equipment.

1. To make it possible to knock out pin (1) of tooth (2), put block
(5) under the bottom of the bucket, and set so that the bottom
surface of the bucket is horizontal.

2. Place a bar on the head of pin (1), hit the bar with a hammer to
knock out the pin, then remove tooth (2).

REMARK
If the bucket teeth cannot be safely removed by this mothod,
have your Komatsu distributor replace the bucket teeth.

3. Clean the mounting face. Fit a new tooth (2) in the adapter,
push in pin (1) partially by hand, then lock it with a hammer to
install the tooth to the bucket.

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.

MAINTENANCE MAINTENANCE PROCEDURE

REPLACE BUCKET SIDE CUTTER, SHROUD

WARNING
It is dangerous if the work equipment is mistakenly moved when
replacing the bucket side cutters and shroud.
Set the work equipment in a stable condition, stop the engine, then set
lock lever (1) securely to the LOCK position (L).
As the locking pin is knocked out with force, there is danger that the pin
may fly out. Check that there is no one near the machine.
Broken pieces may fly during the replacement operation, so always
wear safety glasses, gloves, or other protective equipment.

Side Cutters
Loosen mounting bolts (2), then remove side cutter (1). Replace
the side cutter, bolts, and nuts with new parts.
Tightening torque for bolts: 3040 to 3630 N·m (310 to 370 kgf·m,
2,242.2 to 2,676.2 lbft)

Shroud
1. Place a bar on the head of pin (1), hit the bar with a hammer to
knock out the pin, then remove tooth (2).
REMARK
If it cannot be removed by this method, for safety reasons, always
contact your Komatsu distributor to have the replacement carried
out.
2. Clean the mounting face. Fit a new shroud (2) in the adapter,
push in pin (1) partially by hand, then lock it with a hammer to
install the tooth to the bucket.

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MAINTENANCE PROCEDURE MAINTENANCE

ADJUST BUCKET CLEARANCE

WARNING
It is dangerous if the work equipment is mistakenly moved when adjusting
the bucket clearance.
Set the work equipment in a stable condition, stop the engine, then set lock
lever (1) securely to the LOCK position (L).

1. Set the work equipment in the position shown in the diagram on

the right, then stop the engine and set the lock lever to the
LOCK position (L).
2. Shift O-ring (1) and measure the amount of play "a".
Measurement is easier if you move the bucket to one side so
that all the play can be measured at one place (the right side in
the diagram).
Use a clearance gauge for easy and accurate measurement.
3. Loosen 4 plate mounting bolts (2), and loosen plate (3).
The shim is a split type, so the operation can be carried out
without removing the bolts.
4. Remove shim (4) corresponding to the amount of play "a"
measured above.

[Example]
In the case of play of 3 mm (0.118 in), remove two 1.0 mm
(0.039 in) shims and one 0.5 mm (0.020 in) shim. Play
becomes 0.5 mm (0.020 in). For shim (4), two types of 1.0 mm
(0.039 in) and 0.5 mm (0.020 in) are used.
When play "a" is smaller than one shim, do not carry out any
maintenance.
5. Tighten the four bolts (2).
If the bolts (2) are too stiff to tighten, pull out pin stopper bolt (5)
for easier tightening.

(6): Arm
(7): Bucket

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MAINTENANCE MAINTENANCE PROCEDURE

CHECK WINDOW WASHER FLUID LEVEL, ADD FLUID

If there is air in the window washer fluid, check the level of the fluid
in window washer tank (1), and if it is low, add automobile window
washer fluid.
The window washer tank (1) is at the rear left of the machine inside
the door.

When adding fluid, be careful not to let any dust get in.

Mixture Ratio of Pure Washer Fluid and Water

The proportion differs according to the ambient temperature, so dilute the washer fluid with water to the following
proportions before adding.

Area, season Proportions Freezing temperature

Washer fluid 1/3: -10°C
Normal
water 2/3 (14°F)

Washer fluid 1/2 : -20°C

Winter in cold area
water 1/2 (-4°F)

Winter in extremely -30°C

Pure washer fluid
cold area (-22°F)

There are two types depending on the freezing temperature:

-10°C (14°F) (general use) and -30°C (-22°F) (cold area use), select according to the area and season.

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MAINTENANCE PROCEDURE MAINTENANCE

CHECK AND MAINTENANCE AIR CONDITIONER

Check Level of Refrigerant (gas)

WARNING
If the refrigerant used in the air conditioner gets into your eyes or on your hands, it may cause loss of sight or frostbite. Do not
touch the refrigerant. Never loosen any part of the refrigerant circuit.
Do not bring any flame close to any point where the refrigerant gas is leaking.

If the level of the refrigerant (gas) is low, the cooling effect will be
reduced. Run the engine at high idle, and check the flow of the
refrigerant gas (R134a) in the refrigerant circuit through the sight
glass (2) (inspection window) of the receiver (1) when the cooler is
running at high speed.
(A) No bubbles in refrigerant flow: Suitable
(B) Some bubbles in flow (bubbles pass continuously):
Lack of refrigerant
(C) Colorless, transparent: No refrigerant

REMARK
When there are bubbles, the refrigerant gas level is low, so contact
your Komatsu distributors to have refrigerant added. If the air
conditioner is run with the refrigerant gas level low, it will cause
damage to the compressor.

Inspection 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.

Inspection and Maintenance Items

Guideline for maintenance

Check, maintenance items Content of check, maintenance
interval
Refrigerant (gas) Charge amount Twice a year (spring, autumn)
Air conditioner condenser Clogged fins Every 500 hours
Compressor Operating condition Every 4000 hours
V-belt Damage, tension Every 250 hours
Operating condition
Blower motor, fan When required
(does it make abnormal noise?)
Control mechanism Operating condition (does it function normally?) When required
Mounting condition, looseness at tightening or
Piping mounts When required
connecting portions, leakage of gas, damage

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MAINTENANCE MAINTENANCE PROCEDURE

WASH WASHABLE FLOOR

WARNING
When setting the machine at an angle, use strong blocks to stabilize the machine and be extremely careful when carrying out
the operation.
If the control levers are touched by mistake, the work equipment or machine may suddenly move, and this may lead to a serious
accident. Always set the lock lever securely to the LOCK position before standing up from the operator's seat.

NOTICE
When carrying out this operation, be careful not to get water on the monitor and connectors inside the operator's cab.
Never spray water above the pedestal of the operator's seat (2).
If any water splashes on the surrounding equipment, be sure to wipe it off.

With the washable floor, it is possible to flush out the dirt on the cab floor directly with water.

Washing Washable Floor Mat

1. Stop the machine on horizontal ground, lower the bucket to the ground, and then stop the engine.
2. When washing the floor mat, use a brush to remove the dust, or direct the water onto the mat and wash it with
a brush.

Method of Washing
1. Set the machine at an angle.
For details, see "Method of Setting Machine at Angle (PAGE 4-39)"
2. Swing the upper structure slowly so that water drain holes (3)
in the cab floor are at a low position.

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MAINTENANCE PROCEDURE MAINTENANCE

3. Lower the work equipment to the ground and set the machine
in a stable condition.

4. Set lock lever (1) to LOCK position (L) and stop the engine.

5. Remove the floor mat holder plate (4).

6. Remove the floor mat.
7. Remove the cap from water drain hole (3).
8. Flush out the dirt on the floor directly with water through water
drain hole (3).

9. After completing the washing operation, install the cap in water drain hole (3).
10. Fit the floor mat, then secure it with floor mat holder plate (4).

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MAINTENANCE MAINTENANCE PROCEDURE

Method of Setting Machine at Angle

Method Using Slope

WARNING
Select a solid and smooth slope.
Always put blocks under the track to prevent the machine from moving, and dig the work equipment into the ground.

1. Stop the machine so that the work equipment is on the downhill

side.
2. Put blocks under the track and dig the work equipment into the
ground.

Method Using Block

WARNING
Select a firm flat place.
Put strong blocks under the undercarriage to stabilize the machine and be extremely careful when carrying out the operation.

1. Raise the chassis with the boom and arm.

When doing this, operate the levers slowly.
2. Insert block (5) under the raised track to make the machine
stable.

3. Raise the boom slowly and lower the machine.

When doing this, check that the machine is always stable.

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MAINTENANCE PROCEDURE MAINTENANCE

BLEEDING AIR FROM HYDRAULIC SYSTEM

For details, see "STARTING ENGINE (PAGE 3-86)". If it is necessary to refer to the items for starting the engine,
moving the machine off, steering, or stopping, see the OPERATION section.
1. Bleeding air from pump
1) Loosen air bleeder (1) and check that oil oozes out from the
air bleeder.
2) If the oil does not ooze out, remove the drain hose from the
hydraulic pump case and fill the pump case completely
with hydraulic oil through drain port (2).
Hold the removed hose firmly, keeping the mouthpiece
higher than the oil level in the hydraulic tank so that oil will
not spill out of the hose.
3) After completing the air bleed operation, tighten air bleeder
(1) and install the drain hose.

NOTICE
If the drain hose is installed first, oil will spurt out from bleeder hole (1).
If the pump is operated without filling the pump case with hydraulic oil, abnormal heat will be generated and this may cause an
unexpected damage to the pump.

2. Starting engine
Start the engine, referring to "STARTING ENGINE (PAGE 3-86)".
Run the engine at low idle for 10 minutes after starting, then start operations.

3. Bleeding air from cylinders

1) Run the engine at low idle, and extend and retract each cylinder 4 to 5 times, taking care that a cylinder is
not moved to the end of its stroke. (Stop the cylinder approx. 100 mm (3.9 in) short of its stroke end)
2) Next, operate each cylinder 3 to 4 times to the end of its stroke.
3) Finally, operate each cylinder 4 to 5 times to the end of its stroke to completely remove the air.

NOTICE
If the engine is run at high speed immediately after startup or a cylinder is pushed up to its stroke end, air taken inside the cylinder
may cause damage to the piston packing.

4. Bleeding air from swing motor

1) Run the engine at low idling, loosen the S port hose, and check that oil oozes out from the S port hose.

NOTICE
Do not operate the swing under any circumstances.

2) If no oil oozes out, stop the engine, remove the S port hose, and fill the inside of the motor case with hydraulic
oil.
3) After completely bleeding the air, tighten the S port hose.
4) Run the engine at low idle and slowly swing at least two times uniformly to the left and right. This will
automatically bleed the air from the swing circuit.

NOTICE
If the air is not bled from the swing motor, the motor bearings may be damaged.
When replacing the travel motor safety valve, please contact your Komatsu distributor to have it replaced and to have the air
bled.

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MAINTENANCE MAINTENANCE PROCEDURE

5. Bleeding air from travel motor

(Bleed the air only when the oil inside the travel motor case has been drained.)
1) Run the engine at low idling, loosen air bleeder (1), and
check that oil flows out.

2) Run the engine at low idle and swing the work equipment
90° to bring it to the side of the track.
3) Jack up the machine until the track is raised slightly from
the ground. Rotate the track under no load for 2 minutes.
Repeat this procedure on both the left and right sides.

6. Bleeding air from attachment (when installed)

If a breaker or other attachment has been installed, run the engine at low idle and operate the attachment pedal
repeatedly (approx. 10 times) until the air has been bled from the attachment circuit.

NOTICE
If the method of bleeding the air from the attachment itself is specified by the manufacturer, bleed the air according to the
specified procedure.
After completing the air bleeding operation, stop the engine, and leave the machine for 5 minutes before starting operations.
This will remove the air bubbles in the oil inside the hydraulic cylinders.
Check that there is no leakage of oil and wipe off any oil that has been spilled.
After completing the air bleeding operation, inspect the oil level, and if the oil level is low, add oil.

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MAINTENANCE PROCEDURE MAINTENANCE

METHOD FOR RELEASING INTERNAL PRESSURE IN HYDRAULIC CIRCUIT

WARNING
The hydraulic system is always under internal pressure, so when inspecting or replacing the piping or hoses, always release
the pressure in the circuit before starting. If the pressure is not released, high pressure oil may spurt out and cause serious
personal injury.
The parts and oil are at high temperature after the engine is stopped, and may cause serious burns. Wait for the temperature
to go down before starting the operation.
When the oil filler cap is removed, oil may spurt out, so turn the cap slowly to release the pressure before removing the cap.

1. Stop the machine on firm level ground.

2. Turn the starting switch to ON position (B) within 15 seconds

after stopping the machine. Then set the lock lever to the
FREE position (F) and operate each control lever (work
equipment, travel) fully in each direction to release the internal
pressure.

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MAINTENANCE MAINTENANCE PROCEDURE

3. Loosen oil filler cap (F) at the top of the hydraulic tank slowly to
release the internal pressure.

CHECK NITROGEN GAS CHARGE PRESSURE IN ACCUMULATOR (control circuit)

NOTICE
If the nitrogen gas charge pressure in the accumulator is low and operations are continued, it will become impossible to release
the remaining pressure inside the hydraulic circuit if a failure occurs on the machine.

Check the nitrogen gas charge pressure as follows.

1. Set the work equipment to maximum reach as shown in the
diagram on the right.

2. Stop the engine and carry out the LOWER operation for the boom.
3. Check that the tip of the bucket drops at least 1 m (3 ft).

If the tip of the bucket drops less than 1 m (3 ft), the charge pressure inside the accumulator is low, so contact
your Komatsu distributor.

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MAINTENANCE PROCEDURE MAINTENANCE

CHECK BEFORE STARTING

For details of the following items, see "Checks Before Starting (PAGE 3-73)" in the OPERATION section.
Check coolant level, add coolant
Check oil level in engine oil pan, add oil
Check fuel level, add fuel
Check water separator, drain water and sediment
Drain water and sediment from fuel tank
Check oil level in hydraulic tank, add oil
Check working lamp switch
Check electric wiring
Check function of horn

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MAINTENANCE MAINTENANCE PROCEDURE

EVERY 50 HOURS MAINTENANCE

LUBRICATING
NOTICE
If any abnormal noise is generated from any greasing point, carry out greasing regardless of the greasing interval.
Carry out greasing every 10 hours for the first 50 hours on a new machine.
After the machine was subjected to jobs in the water, be sure to grease the wet pins.

1. Set the machine to the greasing posture shown on the right,

lower the work equipment to the ground, then stop the engine.
2. Using a grease pump, pump in grease through the grease
fittings shown by arrows.
3. After greasing, wipe off any old grease that was pushed out.

(1) Arm-Link coupling pin (1 place)

(2) Arm-Bucket coupling pin (1 place)

(3) Link coupling pin (2 places)

(4) Bucket cylinder rod pin (1 place)
(5) Bucket-Link coupling pin (1 place)

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MAINTENANCE PROCEDURE MAINTENANCE

EVERY 250 HOURS MAINTENANCE

Maintenance for every 50 hours service should be carried out at the same time.

CHECK OIL LEVEL IN SWING MACHINERY CASE, ADD OIL

WARNING
Parts and oil are at high temperature immediately after the engine is stopped and may cause serious burns. Wait for the oil
temperature to go down before performing this operation.

1. Remove dipstick (G) and wipe the oil from the dipstick with a
cloth.
2. Fully insert dipstick (G) into the filler pipe.
3. When dipstick (G) is pulled out, if oil level is between the H and
L marks of the gauge, oil level is proper.
4. If the oil does not reach the L mark on dipstick (G), add engine
oil through dipstick insertion hole (F).
When refilling, remove bleeding plug (1).
5. If the oil is above the L mark on the dipstick, loosen drain valve
(P) and drain the excess oil.
For details of the method of draining the oil, see "CHANGE OIL
IN SWING MACHINERY CASE (PAGE 4-69)".
6. After checking oil level or adding oil, insert the dipstick into the
hole and install air bleeding plug (1).

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MAINTENANCE MAINTENANCE PROCEDURE

CHECK OIL LEVEL IN FINAL DRIVE CASE, ADD OIL

WARNING
The parts and oil are at high temperature immediately after the engine is stopped, and may cause serious burns. Wait for the
temperature to go down before starting the operation.
If there is still pressure remaining inside the case, the oil or plug may fly out.
Loosen the plug slowly to release the pressure.

Prepare a handle.
1. Set the TOP mark at the top, with the UP mark and plug (P)
perpendicular to the ground surface.
2. Remove plug (F) using the handle. When the oil level reaches
a point 10 mm (0.4 in) below the bottom of the plug hole, the
correct amount of oil has been added.
3. If the oil level is too low, install plug (F), operate the travel
levers, and drive forward or in reverse to rotate the sprocket
one turn. Then repeat Step 2 to check again.
4. If the oil level is low, add engine oil through plug hole (F) until
the oil overflows from plug hole (F).
5. After checking, install plug (F).
Tightening torque for plugs (F): 68.6 ± 9.8 N·m (7 ± 1 kgf·m,
50.6 ± 7.2 lbft)

REMARK
There are two plugs (F). Add oil through the one easier to fill oil and
through which no internal gears are to be seen.

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MAINTENANCE PROCEDURE MAINTENANCE

CHECK LEVEL OF BATTERY ELECTROLYTE

Perform this check before operating the machine.

WARNING
Do not use the battery if the battery electrolyte level is below the LOWER LEVEL line. This will accelerate deterioration of the
inside of the battery and reduce the service life of the battery. In addition, it may cause an explosion.
The battery generates flammable gas and there is danger of explosion, do not bring fire or sparks near the battery.
Battery electrolyte is dangerous. If it gets in your eyes or on your skin, wash it off with a large amount of water and consult a
doctor.
When adding distilled water to the battery, do not allow the battery electrolyte to go above the UPPER LEVEL line. If the
electrolyte level is too high, it may leak and cause damage to the paint surface or corrode other parts.

NOTICE
When adding distilled water in cold weather, add it before starting operations in the morning to prevent the electrolyte from
freezing.

Inspect the battery electrolyte level at least once a month and follow the basic safety procedures given below.
Open cover (1) at the rear left side of the machine. The batteries
are installed at (A) part.

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MAINTENANCE MAINTENANCE PROCEDURE

When Checking 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. Use a wet cloth to clean the area around the electrolyte level
lines and check that the electrolyte level is between the
UPPER LEVEL (U.L.) and LOWER LEVEL (L.L.) lines.
If the battery is wiped with a dry cloth, static electricity may
cause a fire or explosion.

2. If the electrolyte level is below the midway point between the

U.L. and L.L. lines, remove cap (1) and add distilled water to
the U.L. line.
3. After adding distilled water, tighten cap (1) securely.

REMARK
If distilled water is added to above the U.L. line, use a syringe to
lower the level to the U.L. line. Neutralize the removed fluid with
baking soda (sodium bicarbonate), then flush it away with a large
amount of water or consult your Komatsu distributor or battery
maker.

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MAINTENANCE PROCEDURE MAINTENANCE

When it is Impossible to Check Electrolyte Level from Side of Battery

If it is impossible to check the electrolyte level from the side of the battery, or there is no display of the UPPER
LEVEL line on the side of the battery, check as follows.
1. Remove cap (1) at the top of the battery, look through the water
filler port, and check the electrolyte surface. If the electrolyte
does not reach the sleeve, add distilled water so that the level
reaches the bottom of the sleeve (UPPER LEVEL line) without
fail.

Use the diagram below for reference, and check if the electrolyte reaches the bottom of the sleeve.

2. After adding distilled water, tighten cap (1) securely.

REMARK
If distilled water is added to above the bottom of the sleeve, use a syringe to lower the level to the bottom of the
sleeve. Neutralize the removed fluid with baking soda (sodium bicarbonate), then flush it away with a large amount
of water or consult your Komatsu distributor or battery maker.

When it is Possible to Use Indicator to Check Electrolyte Level

If it is possible to use an indicator to check the electrolyte level, follow the instructions given.

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MAINTENANCE MAINTENANCE PROCEDURE

LUBRICATE SWING CIRCLE

1. Lower the work equipment to the ground.
2. Using a grease pump, pump in grease through the grease
fittings shown by arrows. (2 places)
3. After greasing, wipe off any old grease that was pushed out.

CHECK FAN BELT, ALTERNATOR BELT TENSION, ADJUST

Inspection
The deflection of the belt should be approx. 13 mm (0.5 in) when
pressed with a finger force of approx. 58.8N (6 kgf) at mid-point (a)
between the alternator pulley and the fan pulley.

(A): Alternator pulley

(B): Fan pulley
(C): Crankshaft pulley

Adjustment
1. Loosen bolts and nuts (1), (2), (3).
Turn nut (4) clockwise to move alternator (5) so that the belt
deflects by approx. 13 mm (0.5 in) with applied force of approx.
6 kg (58.8 N).
2. Tighten bolts and nuts (1), (2) and (3) to secure alternator (5).
Tightening torque
Lock nut(1) and (4): 137.2 ± 53.9 N·m (14 ± 5.5kgf·m, 101.3 ±
39.8 lbft)
Bolt(2): 33.3 ± 4.9N·m (3.4 ± 0.5kgf·m, 24.6 ± 3.6 lbft)
Bolt(3): 127.4 ± 19.6N·m (13 ± 2kgf·m, 94.0 ± 14.5 lbft)

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MAINTENANCE PROCEDURE MAINTENANCE

3. Check for damage to the pulleys, and wear of the groove and belt. Be particularly careful to check that the belt
is not in contact with the bottom of the groove.
4. If the belt has elongated and there is no more allowance for adjustment, or if the belt is cut or cracked, replace
the belt.
5. After replacing the belt, operate for one hour, then adjust again.

CHECK AIR CONDITIONER COMPRESSOR BELT TENSION, ADJUST

Checking
The deflection of the belt should be 14 to 16 mm (0.6 in) when
pressed with a finger force of approx. 58.8N (6 kgf) at mid-point (a)
between the crankshaft pulley and the compressor pulley.

(A): Compressor pulley

(B): Crankshaft pulley

Adjustment
1. Loosen bolts (1) and (2), then move compressor (3) to adjust
the belt tension.
2. When the deflection is correct, tighten bolts (1) and (2) to hold
the compressor in position.
3. Check for damage to the pulleys, and wear of the V-groove and
V-belt. Be particularly careful to check that the V-belt is not in
contact with the bottom of the V-groove.
4. If the belt has elongated and there is no more allowance for
adjustment, or if the belt is cut or cracked, replace the belt.
5. After replacing the V-belt, operate for one hour, then adjust
again.

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MAINTENANCE MAINTENANCE PROCEDURE

EVERY 500 HOURS MAINTENANCE

Maintenance for every 250 hours service should be carried out at the same time.

LUBRICATING
NOTICE
During the initial 50 hours breaking-in period for a new machine, carry out lubrication every 10 hours.
If digging operations have been carried out in water (such as digging holes), always carry out greasing for the pins that were
under water.
For heavy-duty operations, such as hydraulic breaker work, carry out lubrication every 100 hours.

1. Set the machine to the greasing posture shown on the right,

lower the work equipment to the ground, then stop the engine.
2. Using a grease pump, pump in grease through the grease
fittings shown by arrows.
3. After greasing, wipe off any old grease that was pushed out.

(1) Boom cylinder rod pin (2 places)

(2) Arm cylinder foot pin (1 place)

(3) Boom-Arm coupling pin (1 place)

(4) Arm cylinder rod end (1 place)
(5) Bucket cylinder foot pin (1 place)

(6) Boom cylinder foot pin (2 places)

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MAINTENANCE PROCEDURE MAINTENANCE

(7) Boom foot pin (2 places)

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.

MAINTENANCE MAINTENANCE PROCEDURE

REPLACE FUEL FILTER CARTRIDGE

(Machines equipped without additional fuel filter cartridge)

WARNING
After the engine has been operated, all parts are at high temperature, so do not replace the filter immediately. Wait for all parts
to cool down before starting the operation.
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 fire or flame close.
Be careful when opening the air bleed plug in the fuel filter head. It is still under pressure, so fuel may spurt out.

NOTICE
Genuine Komatsu fuel filter cartridges use a special filter that has highly efficient filtering ability. When replacing the filter
cartridge, always use a genuine Komatsu part.
The common rail fuel injection system used on this machine consists of more precise parts than the conventional injection
pump and nozzle.
If any part other than a genuine Komatsu filter cartridge is used, dust or dirt may get in and cause problems with the injection
system. Always avoid using substitute parts.
When carrying out inspection or maintenance of the fuel system, pay more attention than normal to the entry of dirt. If dirt is
stuck to any part, use fuel to wash it off completely.

Container to catch the oil

Prepare a filter wrench

1. Set the container to catch the fuel under the filter cartridge.
2. Using a filter wrench, turn filter cartridge (1) counterclockwise
on remove it.
3. Clean the filter holder, coat the packing surface of the new filter
cartridge thinly with oil, then install the filter cartridge to the filter
holder.

NOTICE
Do not fill the fuel filter cartridge with fuel.
Remove cap (B) and install the fuel filter.

4. When installing, tighten until the packing surface contacts the seal surface of the filter holder, then tighten it 3/4
of a turn.
If the filter cartridge is tightened too far, the packing will be damaged and this will lead to leakage of fuel. If the
filter cartridge is too loose, fuel will also leak from the packing, so always tighten the correct amount.

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MAINTENANCE PROCEDURE MAINTENANCE

5. After completion of the replacement of fuel filter cartridge (1), bleed the air.

Bleed the air as follows:

6. Add fuel to the fuel tank until full (to FULL mark on the fuel gauge).
7. After replacing filter cartridge (1), loosen air bleed plug (B) in
the filter head (2).
8. Loosen the knob of priming pump (3), then pump the knob until
no more bubbles come out of air bleed plug (B).
9. Tighten air bleed plug (B).
Tightening torque: 4.9 to 6.9 N·m (0.5 to 0.7 kgf·m, 3.6 to 5.1
lbft)
10. Push the knob of priming pump (3) in and tighten it.

11. After replacing the filter cartridge, start the engine and check that there is no leakage of fuel from the filter seal
surface. If there is any leakage of fuel, check the tightening of the filter cartridge. If there is still leakage of fuel,
follow Step 1 and 2 to remove the filter cartridge, then check the packing surface for damage or foreign material.
If any damage or foreign material is found in the packing, replace the cartridge with a new part, then repeat Steps
3 - 10 to install the filter cartridge.

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MAINTENANCE MAINTENANCE PROCEDURE

CHECK, WASH FUEL STRAINER

1. Turn fuel supply valve lever (2) at the bottom face of fuel tank
(1) to the (L) position to close it.
2. Open the door at the right side of the machine, remove cap (3)
of the strainer case, then remove the strainer and wash the
strainer and strainer case.
The strainer forms one unit with cap (3).
3. After checking and cleaning, insert the strainer in the strainer
case, then tighten cap (3).
4. Turn fuel supply valve lever (2) to the (F) position to open it.

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MAINTENANCE PROCEDURE MAINTENANCE

CHECK SWING PINION GREASE LEVEL, ADD GREASE

Prepare a scale.
1. Swing 3 times each to the left and right, then stop the machine.
2. Remove bolts (1) (2 bolts) on the top of the revolving frame and
remove cover (2).
3. Insert scale (3) through inspection and maintenance hole (A)
into the grease, and check that height (S) of the grease is at
least 54 mm (2.1 in). If the grease level is low, add grease.
4. Check if the grease is milky white. If it is milky white, it is
necessary to change the grease. Please contact your
Komatsu distributor.

The total amount of grease is 33 liters (29.7 kg) [8.7 US gal (65
lb)].

5. Install cover (2) with bolts (1).

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MAINTENANCE MAINTENANCE PROCEDURE

CHANGE OIL IN ENGINE OIL PAN, REPLACE ENGINE OIL FILTER CARTRIDGE
WARNING
Parts and oil are at high temperature immediately after the engine is stopped and may cause serious burns. Wait for the oil
temperature to go down before performing this operation.

Refill capacity: 38 liters (10.04 US gal)

Prepare a filter wrench

1. Remove inspection cover (2) of the undercover directly under
drain valve (P) under the machine, then set a container to catch
the oil.
2. Be careful not to get oil on yourself. Move lever (F) of the drain
valve (P) down slowly to drain the oil, and after draining the oil,
raise the lever (L) to close it.
3. Open the cover of the engine hood, use a filter wrench from the
top of the engine, turn filter cartridge (1) to the left, and remove
it.

4. Clean the filter holder, fill the new filter cartridge with clean oil, coat the thread and packing surface of the new
filter cartridge with clean oil (or coat it thinly with grease), then install it to the filter holder.

REMARK
Check that there is no old packing stuck to the filter holder. If there is any old packing stuck to the filter, it will cause
leakage of oil.

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MAINTENANCE PROCEDURE MAINTENANCE

5. When installing, tighten until the packing surface contacts the seal surface of the filter holder, then tighten it a
further 3/4 to 1 turn.
6. After replacing the filter cartridge, open the engine hood and
add engine oil through oil filler (F) to between the H and L
marks on dipstick (G).
7. Run the engine at idle for a short time, then stop the engine,
and check that the oil level is between the H and L marks on the
dipstick. For details, see "Check Oil Level in Engine Oil Pan,
Add Oil (PAGE 3-74)".
8. Install the undercover and inspection cover (2).

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MAINTENANCE MAINTENANCE PROCEDURE

CLEAN AND INSPECT RADIATOR FINS, OIL COOLER FINS, AFTERCOOLER FINS, FUEL COOLER
FINS, AND AIR CONDITIONER CONDENSER FINS (only machines equipped with air conditioner)
WARNING
If compressed air, high-pressure water, or steam hit your body directly, or they cause dirt or dust to be blown up, there is a hazard
of serious injury. Always use safety glasses, dust mask, or other protective equipment.

NOTICE
When using compressed air for cleaning, blow it keeping some distance to avoid damaging the fins. Damage on the fins can cause
water leakage and overheating. In a dusty job site, check the fins every day, regardless of the maintenance interval.

1. Open the engine hood.

2. Loosen screw (1), then pull up net (2).
3. Clean net (2). (it is to be installed again, as instructed in the
step 8.)
4. Loosen bolts (4) of top cover (3) on the engine side, then slide
cover (3) to the rear.
5. Check the front face and rear face of oil cooler fins (5), radiator
fins (6), aftercooler fins (7), condenser fins (8), and fuel cooler
fins (9). If there are any leaves, mud, or dirt, blow off with
compressed air.
Steam or water may be used instead of compressed air.
6. Check the rubber hose. Replace with a new one if the hose is
found to have cracks or to be hardened by aging. In addition,
check the hose clamps for looseness.

7. Remove undercovers (10) and (11), and clean out all the
leaves, mud, and dirt blown off during the cleaning operation.
8. Insert cleaned net (2) into its original position, then install with
screw (1).
9. Install cover (3) with mounting bolts (4).
10. Install undercovers (10) and (11).

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MAINTENANCE PROCEDURE MAINTENANCE

CLEAN AIR CONDITIONER FRESH/RECIRC FILTERS

WARNING
If compressed air is used, there is danger that dirt may fly and cause personal injury.
Always wear protective glasses, dust mask, and other protective equipment.

NOTICE
As a guideline, the filters should be cleaned every 500 hours, but on dusty jobsites, clean the filters more frequently.

REMARK
If the filter becomes clogged, the air flow will be reduced, and there will be an abnormal noise from the air conditioner
unit.

Cleaning Reticulated Air Filter

1. Remove wing bolts (1) from the inspection window at the
bottom rear left on the inside of the operator's cab, then take
out the recirculated air filter.
2. Clean the filter with compressed air. If there is oil on the filter,
or if the filter is extremely dirty, wash it in a neutral agent. After
rinsing it in water, dry it thoroughly before using it again.
Replace the filter with a new part every year. If the clogging of
the filter cannot be removed by blowing with air or washing in
water, replace the filter immediately.

Cleaning Fresh Air Filter

1. Use the starting switch key to open cover (2) at the rear left of
the operator's cab, then open cover (2) by hand and remove
filter (3) inside the cover.

2. Clean the filter with compressed air. If there is oil on the filter, or if the filter is extremely dirty, wash it in a neutral
agent. After rinsing it in water, dry it thoroughly before using it again.
Replace the filter with a new part every year. If the clogging of the filter cannot be removed by blowing with air
or washing in water, replace the filter immediately.
3. After cleaning, return filter (3) to its original position and close the cover. Use the starting switch key to lock the
cover. Do not forget to remove the starting switch key.

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MAINTENANCE MAINTENANCE PROCEDURE

REMARK
The FRESH filter must be installed facing in the correct direction.
When installing, insert the long (L) end of filter (3) into the filter case
first. If the short (S) end is installed first, cover (2) will not close.

REPLACE BREATHER ELEMENT IN HYDRAULIC TANK

WARNING
The parts and oil are at high temperature immediately after the engine is stopped, and may cause burns. Wait for the
temperature to go down before starting the work.
When removing the oil filler cap, turn it slowly to release the internal pressure, then remove it.

1. Remove the cap of oil filler (F) at the top of the hydraulic tank.

2. Replace element (1) inside the cap.

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MAINTENANCE PROCEDURE MAINTENANCE

REPLACE ADDITIONAL FUEL FILTER CARTRIDGE

(If equipped with machines)

WARNING
After the engine has been operated, all parts are at high temperature, so do not replace the filter immediately. Wait for all parts
to cool down before starting the operation.
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 fire or flame close.
Be careful when opening the air bleed plug in the fuel filter head. It is still under pressure, so fuel may spurt out.

NOTICE
Genuine Komatsu fuel filter cartridges use a special filter that has highly efficient filtering ability. When replacing the filter
cartridge, always use a genuine Komatsu part.
The common rail fuel injection system used on this machine consists of more precise parts than the conventional injection
pump and nozzle.
If any part other than a genuine Komatsu filter cartridge is used, dust or dirt may get in and cause problems with the injection
system. Always avoid using substitute parts.
When carrying out inspection or maintenance of the fuel system, pay more attention than normal to the entry of dirt. If dirt is
stuck to any part, use fuel to wash it off completely.

Container to catch the oil

Prepare a filter wrench

1. Set the container to catch the fuel under the additional fuel filter
cartridge.
2. Using a filter wrench, turn filter cartridge (1) counterclockwise
to remove it.
3. After removing the cartridge, turn cup (2) of the water separator
installed to the bottom of the cartridge counterclockwise. (This
cup is used again.)
4. Install cup (2) to the bottom of the new additional fuel filter
cartridge. (When doing this, always replace the O-ring with a
new part.)
Cup tightening torque: 10 N·m (1.0 kgf·m, 7.2 lbft)
5. Clean the filter holder, fill the new filter cartridge with clean fuel, coat the packing surface thinly with oil, then
install to the filter holder.

NOTICE
When adding fuel, do not remove cap (B). Always add fuel from the 8
small holes (A) on the dirty side.
After adding fuel, remove cap (B) 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
cap (B) when adding fuel. Be careful not to let dirt or dust get into center
portion on the clean side.

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MAINTENANCE MAINTENANCE PROCEDURE

6. When installing, tighten until the packing surface contacts the seal surface of the filter holder, then tighten it 3/4
of a turn.
If the filter cartridge is tightened too far, the packing will be damaged and this will lead to leakage of fuel. If the
filter cartridge is too loose, fuel will also leak from the packing, so always tighten the correct amount.
When tightening with a filter wrench, be extremely careful not to dent or damage the filter.
7. Check that the drain plug at the bottom of the water separator cup is tightened securely.
Tightening torque: 0.2 to 0.45 N·m (0.02 to 0.046 kgf·m, 0.1 to 0.3 lbft)
8. When carrying out standard replacement of the fuel filter cartridge (every 1000 hours), replace the cartridge and
bleed the air. For details, see "REPLACE FUEL FILTER CARTRIDGE (PAGE 4-66)".
9. Start the engine, check that there is no leakage of fuel from the filter seal surface or water separator mounting
surface, then run for approx. 10 minutes at low idling.

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MAINTENANCE PROCEDURE MAINTENANCE

EVERY 1000 HOURS MAINTENANCE

Maintenance for every 250 and 500 hours service should be carried out at the same time.

REPLACE FUEL FILTER CARTRIDGE

(Machines equipped with additional fuel filter cartridge)

WARNING
After the engine has been operated, all parts are at high temperature, so do not replace the filter immediately. Wait for all parts
to cool down before starting the operation.
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 fire or flame close.
Be careful when opening the air bleed plug in the fuel filter head. It is still under pressure, so fuel may spurt out.

NOTICE
Genuine Komatsu fuel filter cartridges use a special filter that has highly efficient filtering ability. When replacing the filter
cartridge, always use a genuine Komatsu part.
The common rail fuel injection system used on this machine consists of more precise parts than the conventional injection
pump and nozzle.
If any part other than a genuine Komatsu filter cartridge is used, dust or dirt may get in and cause problems with the injection
system. Always avoid using substitute parts.
When carrying out inspection or maintenance of the fuel system, pay more attention than normal to the entry of dirt. If dirt is
stuck to any part, use fuel to wash it off completely.

Container to catch the oil

Prepare a filter wrench

1. Set the container to catch the fuel under the filter cartridge.
2. Using a filter wrench, turn filter cartridge (1) counterclockwise
on remove it.
3. Clean the filter holder, coat the packing surface of the new filter
cartridge thinly with oil, then install the filter cartridge to the filter
holder.

NOTICE
Do not fill the fuel filter cartridge with fuel.
Remove cap (B) and install the fuel filter.

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MAINTENANCE MAINTENANCE PROCEDURE

4. When installing, tighten until the packing surface contacts the seal surface of the filter holder, then tighten it 3/4
of a turn.
If the filter cartridge is tightened too far, the packing will be damaged and this will lead to leakage of fuel. If the
filter cartridge is too loose, fuel will also leak from the packing, so always tighten the correct amount.
5. After completion of the replacement of fuel filter cartridge (1), bleed the air.

Bleed the air as follows:

6. Add fuel to the fuel tank until full (to FULL mark on the fuel gauge).
7. After replacing filter cartridge (1), loosen air bleed plug (B) in
the filter head (2).
8. Loosen the knob of priming pump (3), then pump the knob until
no more bubbles come out of air bleed plug (B).
9. Tighten air bleed plug (B).
Tightening torque: 4.9 to 6.9 N·m (0.5 to 0.7 kgf·m, 3.6 to 5.1
lbft)
10. Push the knob of priming pump (3) in and tighten it.

11. After replacing the filter cartridge, start the engine and check that there is no leakage of fuel from the filter seal
surface. If there is any leakage of fuel, check the tightening of the filter cartridge. If there is still leakage of fuel,
follow Step 1 and 2 to remove the filter cartridge, then check the packing surface for damage or foreign material.
If any damage or foreign material is found in the packing, replace the cartridge with a new part, then repeat Steps
3 - 10 to install the filter cartridge.

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MAINTENANCE PROCEDURE MAINTENANCE

REPLACE HYDRAULIC OIL FILTER ELEMENT

WARNING
The parts and oil are at high temperature immediately after the engine is stopped, and may cause burns. Wait for the
temperature to go down before starting the work.
When removing the oil filler cap, turn it slowly to release the internal pressure, then remove it.

NOTICE
If the machine is equipped with a hydraulic breaker, the hydraulic oil will deteriorate much faster than during normal bucket
operations. For details, see "MAINTENANCE INTERVAL FOR HYDRAULIC BREAKER (PAGE 4-17)" when carrying out
maintenance.

1. Set the work equipment on the hard and flat ground in the
maintenance posture as shown in the figure, then lower it to the
ground and stop the engine.

2. Remove the cap from oil filler (F) on top of the hydraulic tank,
and release the internal pressure.
3. Loosen 4 bolts, then remove cover (1).
When doing this, the cover may fly out under the force of spring
(2), hold the cover down when removing the bolts.

REMARK
If the mounting bolts of cover (1) are loosened and the cover is left
as it is for approx. 5 minutes, the pressure inside the case is
released, so the oil in the element is drained and less oil drips when
the element is removed.

4. After removing spring (2), valve (3) and strainer (4), take out
element (5).
5. Clean the removed parts in diesel oil.
6. Install the new element in the place where old element (5) was
installed.
7. Set valve (3) and spring (2) on top of the element.
8. Set cover (1) in position, push it down by hand, and install the
cover with the mouning bolts.
9. Screw in the oil filler cap and install the cover.

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MAINTENANCE MAINTENANCE PROCEDURE

10. To bleed the air, start the engine according to "STARTING ENGINE (PAGE 3-86)" and run the engine at low idle
for 10 minutes.
11. Stop the engine.

REMARK
Wait for at least 5 minutes after stopping the eigine to eliminate bubbles in the oil inside the tank.

12. Check for oil leakage and wipe off any spilled oil.

CHANGE OIL IN SWING MACHINERY CASE

WARNING
Parts and oil are at high temperature immediately after the engine is stopped and may cause serious burns. Wait for the oil
temperature to go down before performing this operation.

Refill capacity: 20 liters (5.28 US gal)

1. Remove cover (A) of the inspection hole.
(Only machines equipped with optional cover)

2. Set a container under drain valve (P) under the machine body
to catch the oil.
3. Loosen drain valve (P) under the body, drain the oil, then
tighten the drain valve again.
4. Remove dipstick (G) and air bleding plug (2), then add the
specified amount of oil through filler port (F) of the dipstick
guide.
5. After adding oil, install air bleed plug (2).

6. Pull out dipstick (G) and wipe off oil on the dipstick with cloth.
7. Fully insert dipstick (G) into filler pipe (F), then remove it.
8. The oil level should be between H and L marks on the dipstick
(G). If the oil does not reach the L mark, add oil through oil filler
port (F).
9. If the oil is above the H mark, drain the excess engine oil from
drain valve (P), and check the oil level again.
When draining the oil, first pull hose (1) out from inspection
hole (B), then turn the drain valve to the OPEN position.

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.

MAINTENANCE PROCEDURE MAINTENANCE

CHECK OIL LEVEL IN DAMPER CASE, ADD OIL

WARNING
Parts and oil are at high temperature immediately after the engine is stopped and may cause serious burns. Wait for the oil
temperature to go down before performing this operation.

NOTICE
Park the machine on flat ground and stop the engine. After waiting for more than 30 minutes after stopping the engine, check the
oil level.

1. Open the door on the left side of the machine.

2. Remove plug (P) and check that the oil is up to near the bottom
of the plug hole. If the oil level is low, remove cap (F) and add
oil through the oil filler port to the bottom of the hole of plug (P).

NOTICE
If excess oil is supplied, drain it to the specified amount to avoid
overheating.

3. Install plug (P) and cap (F).

4. Close the door.

CHECK ALL TIGHTENING PARTS OF TURBOCHARGER

Contact your Komatsu distributor to have the tightening portions checked.

CHECK PLAY TURBOCHARGER ROTOR

Contact your Komatsu distributor to have the rotor play checked.

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MAINTENANCE MAINTENANCE PROCEDURE

REPLACE CORROSION RESISTOR CARTRIDGE

WARNING
The oil is at high temperature after the engine has been operated, so never replace the cartridge immediately after finishing
operations.
Wait for the oil to cool down before replacing cartridge.

1. Close valves (1) and (2) at the top of the corrosion resistor.
2. Using a filter wrench, turn cartridge (3) to the left to remove it.
3. Install a new filter cartridge after coating oil on its sealing face.
In the installation, turn the cartridge by two-thirds of one turn
after the packing surface comes to contact with the sealing
face of the cartridge stand.
A genuine Komatsu filter cartridge is recommended for use.
4. Open valve (1).
5. Run the engine and check that there is no leakage of water
from the seal surface.

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.

MAINTENANCE PROCEDURE MAINTENANCE

REPLACE HYDRAULIC TANK ADDITIONAL BREATHER ELEMENT

WARNING
The parts and oil are at high temperature immediately after the engine is stopped, and may cause burns. Wait for the
temperature to go down before starting the work.
When removing the oil filler cap, turn it slowly to release the internal pressure, then remove it.

1. Remove nut (2) of breather assembly (1) at the top of the

hydraulic tank, then remove cover (3).
2. Replace filter element (4) with a new element.
3. Install cover (3) and nut (2).

CHECK NITROGEN GAS CHARGE PRESSURE IN ACCUMULATOR (for breaker)

(If equipped)

A special tool is needed for inspecting and charging with nitrogen gas.
Have your Komatsu distributor inspect and charge the accumulator.

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.

MAINTENANCE MAINTENANCE PROCEDURE

EVERY 2000 HOURS MAINTENANCE

Maintenance for every 250, 500 and 1000 hours service should be carried out at the same time.

CHANGE OIL IN FINAL DRIVE CASE

WARNING
The parts and oil are at high temperature immediately after the engine is stopped, and may cause serious burns. Wait for the
temperature to go down before starting the operation.
If there is still pressure remaining inside the case, the oil or plug may fly out.
Loosen the plug slowly to release the pressure.

Refill capacity: each 12 liters (3.17 US gal)

Prepare a handle.
1. Set the TOP mark at the top, with the TOP mark and plug (P)
perpendicular to the ground surface.
2. Set a container under plug (P) to catch the oil.
3. Remove plugs (P) and (F) with the handle and drain the oil.

REMARK
Check the O-rings in the plugs for damage. If necessary, replace
with new ones.

4. Tighten plug (P).

5. Add oil through the hole of plug (F).
6. When oil begins to overflow from the plug (F) hole, install plug
(F).
Tightening torque of plugs (P) and (F):
68.6 ± 9.8 N·m (7 ± 1 kgf·m, 50.6 ± 7.2 lbft)

REMARK
There are two plugs (F). Add oil through the one easier to fill oil and
through which no internal gears are to be seen.

CHECK INJECTOR
Check the color of the exhaust gas visually. If there is any abnormality in the exhaust gas color, contact your
Komatsu distributor for inspection.
For details, see "TROUBLES AND ACTIONS (PAGE 3-145)" "Exhaust color is black".

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.

MAINTENANCE PROCEDURE MAINTENANCE

CLEAN HYDRAULIC TANK STRAINER

WARNING
The parts and oil are at high temperature immediately after the engine is stopped, and may cause burns. Wait for the
temperature to go down before starting the work.
When removing the oil filler cap, turn it slowly to release the internal pressure, then remove it.

1. Remove 4 bolts, then remove cover (1). When doing this,

cover (1) may fly out under the force of spring (2), so keep the
cover pressed down while removing the bolts.
2. Hold the top of rod (3) and pull up to remove spring (2) and
strainer (4).
3. Remove any dirt stuck to strainer (4), then wash it in flushing
oil. If strainer (4) is damaged, replace it with a new part.
4. When installing, insert strainer (4) into protruding part (5) of the
tank, and assemble.
5. Assemble so that the protruding part at the bottom of cover (1)
holds spring (2), then tighten with the bolt.

CLEAN ENGINE BREATHER

WARNING
The parts and oil are at high temperature after the engine is stopped, and may cause serious burns. Wait for the temperature
to go down before cleaning the engine breather.
When using compressed air, there is a hazard that dirt may be blown up and cause serious injury.
Always use safety glasses, dust mask, or other protective equipment.

1. Wipe away dust around the breather.

2. Loosen the clamp (1), remove the breather hose, then remove
breather (2) from the cylinder head cover.
3. Clean the breather body with light oil or cleaning oil.
4. Replace O-ring with new one. Coat a new O-ring with engine
oil, set it, then install breather (2).
5. Check the breather hose and pipe. If caked oil (sludge) adhere
to insides, replace the hose and pipe with new parts.

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MAINTENANCE MAINTENANCE PROCEDURE

CLEAN, CHECK TURBOCHARGER

Contact your Komatsu distributor for cleaning and inspection.

CHECK ALTERNATOR, STARTING MOTOR

The brushes may be worn or the bearing may have run out of grease, contact your Komatsu distributor for inspection
and repairs.
If the engine is started frequently, have this inspection carried out every 1000 hours.

CHECK ENGINE VALVE CLEARANCE, ADJUST

Special tools are needed for inspection and maintenance, please contact your Komatsu distributor.

CHECK VIBRATION DAMPER

Check that there are no cracks or peeling in the outside surface of the rubber.
If any cracks or peeling are found, contact your Komatsu distributor to have the parts replaced.

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MAINTENANCE PROCEDURE MAINTENANCE

EVERY 4000 HOURS MAINTENANCE

Maintenance for every 250, 500, 1000 and 2000 hours service should be carried out at the same time.

CHECK WATER PUMP

Since the pulley may have play, oil may leak, water may leak and
the drain hole (A) may be clogged, contact your Komatsu
distributor for inspection, overhaul or replacement.

CHECK FOR LOOSENESS OF HIGH-PRESSURE PIPING CLAMP, HARDENING OF RUBBER

Check visually and touch with your fingers to check that there are no loose bolts or hardening of rubber parts at
clamps (1) to (10). If there is any looseness or hardened rubber, contact your Komatsu distributor for replacement.

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MAINTENANCE MAINTENANCE PROCEDURE

CHECK FOR MISSING FUEL SPRAY PREVENTION CAP, HARDENING OF RUBBER

Check for any missing fuel spray prevention caps (1) to (11) or fuel spray prevention cover (12), and check also for
any hardened rubber portions. If there are any missing caps or cover or the rubber is hardened, please contact your
Komatsu distributor for repairs.

REPLACE INJECTOR NOZZLE ASSEMBLY

Please contact your Komatsu distributor to have the injector nozzle assembly replaced.

4 - 77
.

MAINTENANCE PROCEDURE MAINTENANCE

EVERY 5000 HOURS MAINTENANCE

Maintenance for every 250, 500 and 1000 hours service should be carried out at the same time.

CHANGE OIL IN HYDRAULIC TANK

WARNING
The parts and oil are at high temperature immediately after the engine is stopped, and may cause burns. Wait for the
temperature to go down before starting the work.
When removing the oil filler cap, turn it slowly to release the internal pressure, then remove it.

NOTICE
If the machine is equipped with a hydraulic breaker, the hydraulic oil will deteriorate much faster than during normal bucket
operations. For details, see "MAINTENANCE INTERVAL FOR HYDRAULIC BREAKER (PAGE 4-17)" when carrying out
maintenance.

Refill capacity: 248 liters (65.52 US gal)

Prepare a handle (for the socket wrench).
1. Swing the upper structure 45° to the left so that drain plugs
(P1), (P2) under the tank and the bottom of the pump suction
tube are in the middle between the left and right tracks.
2. Retract the arm and bucket cylinders, then lower the boom and
put the teeth in contact with the ground.
3. Set the lock lever to the LOCK position and stop the engine.
4. Remove the 2 undercovers under drain plugs (P1) and (P2).

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MAINTENANCE MAINTENANCE PROCEDURE

5. Remove the cap of oil filler port (F) at the top of the hydraulic
tank.
6. Set a container to catch the oil under the drain plug at the
bottom of the machine, then remove drain plugs (P1) and (P2),
and drain the oil.
Check the O-rings installed to drain plugs (P1) and (P2). If
there is any damage, replace the O-ring. After draining the oil,
tighten drain plugs (P1) and (P2).
Tightening torque: 68.6 ± 9.81 N·m (7 ± 1 kgf·m, 50.6 ±
7.2 lbft)
When removing drain plugs (P1) and (P2), be careful not to
get the oil over yourself.
Remove drain plug (P1) at the bottom of the tank first, then
remove plug (P2) at the suction tube. This makes it
possible to drain approximately the same amount of oil from
the two places.
7. Add the specified amount of new and clean oil through oil filler port (F). Check that the oil level is between H and
L on the sight gauge.
For details of oil level check, see "Check Oil Level in Hydraulic Tank, Add Oil (PAGE 3-77)".
8. Install the 2 undercovers under drain plugs (P1) and (P2).

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.

MAINTENANCE PROCEDURE MAINTENANCE

EVERY 8000 HOURS MAINTENANCE

Maintenance for every 100, 250, 500, 1000, 2000 and 4000 hours service should be carried out at the same time.

REPLACE HIGH-PRESSURE PIPING CLAMP

Contact your Komatsu distributor to have the engine high-pressure clamps replaced.

REPLACE FUEL SPRAY PREVENTION CAP

Contact your Komatsu distributor to have the fuel spray prevention cap replaced.

4 - 80
.

5-1
.

SPECIFICATIONS SPECIFICATIONS

SPECIFICATIONS
Item Unit PC400-7 PC400LC-7 PC450-7 PC450LC-7
Operating weight 42,400 43,500 44,000 44,600
(Variable gauge specification) (93,492) (95,918) (97,020) (98,343)
Operating weight kg 41,200 42,200 42,700 43,700
(Fixed gauge specification) (lb) (90,846) (93,051) (94,154) (96,359)
Operating weight (Fixed gauge 41,200 42,500 42,700 43,700
specification for America) (90,846) (93,713) (94,154) (96,359)
m3 1.9 1.9 1.9 1.9
Bucket capacity
(cu.yd) (2.5) (2.5) (2.5) (2.5)
Name of engine - KOMATSU SAA6D125E-3 deisel engine
kW 246(330) 246(330) 246(330) 246(330)
Rated horsepower of engine
(HP)/rpm /1,850 /1,850 /1,850 /1,850
mm 11.945 11.945 12,040 12,040
A Overall length
(ft in) (39' 2") (39' 2") (39' 6") (39' 6")
mm 3,635 3,635 3,670 3,670
B Overall height
(ft in) (11' 11") (11' 11") (12') (12')
Overall width 3,490 3,590 3,490 3,490
C
(Variable gauge specification) mm (11' 5") (11' 9") (11' 5") (11' 5")
Overall width (ft in) 3,340 3,440 3,340 3,340
C
(Fixed gauge specification) (10' 11") (11' 3") (10' 11") (10' 11")
mm 600 700 600 600
D Track shoe width
(ft in) (1' 12") (2' 4") (1' 12") (1' 12")
mm 3,250 3,250 3,250 3,250
E Height of cab
(ft in) (10' 8") (10' 8") (10' 8") (10' 8")
mm 3,645 3,645 3,645 3,645
F Radius of upper structure
(ft in) (11' 12") (11' 12") (11' 12") (11' 12")
mm
G Overall length of track - - - -
(ft in)
mm 4,020 4,350 4,020 4,350
H Tumbler center distance
(ft in) (13' 2") (14' 3") (13' 2") (14' 3")
mm 685 685 685 685
Min. ground clearance
(ft in) (2' 3") (2' 3") (2' 3") (2' 3")
km/h 3.0/4.4/5.5 3.0/4.4/5.5 3.0/4.4/5.5 3.0/4.4/5.5
Traveling speed (low/middle/high)
(MPH) (1.9/2.7/3.4) (1.9/2.7/3.4) (1.9/2.7/3.4) (1.9/2.7/3.4)
Swing speed rpm 9.1 9.1 9.1 9.1
"Variable gauge specification" means the machine can extend and retract overall width (C) of the track frame.
"Fixed gauge specification" means the machine cannot extend or retract overall width (C) of the track frame.

5-2
.

SPECIFICATIONS SPECIFICATIONS

5-3
.

SPECIFICATIONS SPECIFICATIONS

Working ranges Unit PC400-7 PC400LC-7 PC450-7 PC450LC-7

mm 12,025 12,030 12,020 12,020
A Max. digging reach
(ft in) (39' 5") (39' 6") (39' 5") (39' 5")
mm 7,820 7,830 7,810 7,810
B Max. digging depth
(ft in) (25' 8") (25' 8") (25' 7") (25' 7")
mm 10,915 10,915 10,930 10,930
C Max. digging height
(ft in) (35' 10") (35' 10") (35' 10") (35' 10")
Max. vertical wall digging mm 6,870 6,870 6,660 6,660
D
depth (ft in) (22' 6") (22' 6") (21' 10") (21' 10")
mm 7,565 7,565 7,625 7,625
E Max. dumping height
(ft in) (24' 10") (24' 10") (25') (25')
mm
F Min. dump height - - - -
(ft in)
Max. digging reached at mm 11,820 11,820 11,800 11,800
G
ground level (ft in) (38' 9") (38' 9") (38' 9") (38' 9")

5-4
.

6-1
.

GENERAL PRECAUTIONS FOR SAFETY ATTACHMENTS AND OPTIONS

GENERAL PRECAUTIONS FOR SAFETY

When installing attachments or options to the machine, it is necessary to pay attention to safety. Please obey the
following precautions strictly when selecting, installing, or using attachments or options.

PRECAUTIONS WHEN SELECTING

Please consult your Komatsu distributor before installing attachments or options to the machine. Depending on
the type of attachment or option, it may be necessary to install a front guard, overhead guard, or other safety
structure to the machine. There may also be problems of the attachment or option hitting the operator's cab.
Install only attachments or options authorized by Komatsu. Komatsu cannot accept any responsibility for any
accident, damage, or failure caused by the use of attachments or options not authorized by Komatsu.

READ THE INSTRUCTION MANUAL THOROUGHLY

Before installing or using any attachment or option, make sure that you thoroughly read and understand the
instruction manuals for the machine and the attachment or option.
If you lose the instruction manual or it is damaged, always obtain an new copy from the attachment manufacturer
or your Komatsu distributor.

PRECAUTIONS WHEN REMOVING OR INSTALLING

When removing or installing the attachment or option, obey the following precautions, and take care to ensure safety
during the operation.
Carry out the removal and installation operation on a flat, firm ground surface.
When the operation is carried out by two or more workers, choose the leader and follow his instructions.
Use a crane when handling heavy objects (more than 25 kg (55 lb)). (The crane must be operated by a qualified
operator.)
Never go under a load raised by the crane.
Do not carry out operations with the load kept raised by the crane. Always use a stand to prevent the load from
falling.
When removing a heavy part, consider the balance after it is removed. To prevent the machine from tipping over,
set a support in position if necessary before removing the part.
Before installing or after removing the attachment or option, set it in a stable condition to prevent it from falling
over.
For details of the removal or installation operation, please consult your Komatsu distributor.

PRECAUTIONS WHEN USING

When long or heavy work equipment is installed, remember the following precautions. Before starting operations,
move the machine to a safe place and carry out a test operation to make sure that you fully understand the
movement, center of gravity, and working range of the machine.
Do not swing the work equipment if the machine is at an angle. If the work equipment is swung with the machine
at an angle, there is danger that the machine will tip over.
Always maintain a safe distance from obstacles in the surrounding area when operating. If long work equipment
is installed, the working range becomes larger.
If heavy work equipment is installed, pay careful attention to the following precautions.
The swing overrun (the distance the work equipment moves before completely stopping after the swing brake
is applied) will be greater. There is danger of hitting objects if the swing overrun is miscalculated, so allow extra
space to the swing position when swinging.
The hydraulic drift of the work equipment (the amount of the work equipment moves down under its own weight
when it is stopped in a raised position) also becomes greater. Do not stop the work equipment in a raised
position; always lower it to the ground.
Do not swing, lower, or stop the work equipment suddenly. There is danger that the machine may tip over.
Do not suddenly extend or retract the boom cylinder. The shock may cause the machine to tip over.

6-2
.

ATTACHMENTS AND OPTIONS MACHINE READY FOR ATTACHMENT

MACHINE READY FOR ATTACHMENT

LOCATIONS

(1) Stop valve (4) Lock pin

(2) Selector valve (5) Breaker circuit additional oil filter
(3) Attachment control pedal (6) Accumulator

Stop Valve
This valve (1) stops the flow of the hydraulic oil.
(a) FREE: Hydraulic oil flows.
(b) LOCK: Hydraulic oil stops.
When removing or installing attachments, set this valve to the
LOCK position.

6-3
.

MACHINE READY FOR ATTACHMENT ATTACHMENTS AND OPTIONS

Selector Valve
This valve (2) switches the flow of hydraulic oil.
It is automatically switched according to the selected working
mode. It is necessary to switch the working mode to match the
attachment that is installed. For details of switching the working
mode, see "HYDRAULIC CIRCUIT (PAGE 6-7)".

NOTICE
If a service circuit from the attachment maker has been added, the return
circuit may not switch automatically.

Attachment Control Pedal

WARNING
Do not carry out operations with your foot on the pedal. If the pedal is depressed by mistake, the attachment may suddenly move
and cause a serious accident. Lock the pedal with the lock pin when you are not operating the attachment.

This pedal (3) is used to control the attachment.

When the front, center (neutral), and rear of the pedal are
depressed, the movement of the attachment is as follows.

Hydraulic breaker
Front of pedal (A): Actuated
Center of pedal N: Stopped
Rear of pedal (B): Stopped

Regarding other attachments, hold a meeting with the attachment

maker at the time of installation to confirm the operation of the
pedal and attachment before using it.

REMARK
This pedal cover (3) differs in thickness at both ends. It can be stalled facing in either direction, so install it according
to your own preference.

6-4
.

ATTACHMENTS AND OPTIONS MACHINE READY FOR ATTACHMENT

Lock Pin
This pin (4) locks the control pedal.
Position (a): Locked
Position (b): Only front of pedal can be operated to full position
(rear is locked)
Position (c): Both front and rear of pedal can be operated to
full position
When using a breaker, select B mode on the monitor and set the
lock pin to position (b).
When not using the attachment, set the lock pin to position (a).
When using a Crasher, select A or E mode on the monitor and
set the lock pin to position (c).

NOTICE
When using a breaker, if the lock pin is set to position (c) and the rear portion (B) of the pedal is depressed, it will cause defective
operation or breakage of the breaker, so always set the lock pin to position (b) when using the breaker.

Breaker Circuit Additional Oil Filter

This filter (5) prevents deterioration of the hydraulic oil when using
a breaker.
Oil only flows when B mode is selected on the monitor.

NOTICE
Always install an additional filter in the return circuit on machines
equipped with a hydraulic breaker.

6-5
.

MACHINE READY FOR ATTACHMENT ATTACHMENTS AND OPTIONS

Accumulator

WARNING
The accumulator is charged with high-pressure nitrogen gas, improper
operation may cause an explosion which could lead to serious injury or
damage. When handling the accumulator, always do as follows:
Pressure in the control circuit cannot be completely removed. When
removing the hydraulic equipment, do not stand in the direction that oil
spurts out when performing the operation.
Loosen the bolts slowly.
Do not disassemble the accumulator.
Do not bring it near flame or dispose of it in fire.
Do not make holes in it or weld it.
Do not hit it, roll it, or subject it to any impact.
When disposing of the accumulator, the gas must be released. Contact
your Komatsu distributor for proper disposal.

This accumulator (6) is installed to reduce the peak pressure in the hydraulic circuit when a breaker is used.
Normally, do not touch it.

NOTICE
For machines equipped with a breaker, when connecting to the breaker piping, it is necessary to install the accumulator
specified by the breaker manufacturer for that breaker model. If the breaker is operated without an accumulator being installed,
the
life of the machine will be reduced. Please contact your Komatsu distributor if you have questions about the applicable
breaker.
If the nitrogen gas charge pressure inside the accumulator goes down, it will become impossible to release the remaining
pressure inside the hydraulic circuit after the engine is stopped. In addition, if operations are continued when the nitrogen
gas
charge pressure is low, it will lead to failure of the hydraulic circuit or the machine.
Check the nitrogen charge pressure periodically.

For details, see "CHECK NITROGEN GAS CHARGE PRESSURE IN ACCUMULATOR (control circuit) (PAGE 4-43)" and "CHECK
NITROGEN GAS CHARGE PRESSURE IN ACCUMULATOR (for breaker) (PAGE 4-72)".

6-6
.

ATTACHMENTS AND OPTIONS MACHINE READY FOR ATTACHMENT

HYDRAULIC CIRCUIT
NOTICE
It is necessary to return the return circuit directly to the return filter when a breaker is used, so use only the B mode. Do not
use any other mode.
When the machine is shipped from the factory, the standard set pressure of the safety valve in the service valve is set as
follows:
When B mode is selected: 17.2 MPa (175 kgf/cm2, 2,485 PSI)
When A or E mode is selected: 20.1 MPa (205 kg/cm2, 2,911 PSI).
The set pressure may have to be adjusted depending on the attachment. In such cases, please ask your Komatsu distributor
to carry out the adjustment.

Switching Hydraulic Circuit

Depending on the type of attachment, set the working mode on the monitor as follows.
The set pressure of the safety valve in the service valve and the hydraulic circuit switch is according to the working
mode selected.

Set pressure of service

Attachment Working mode Hydraulic circuit
safety valve
Return circuit automatically
1-way circuit attachment When shipped from factory:
B mode becomes circuit which does
(such as breaker) 17.2 MPa (175 kgf/cm2, 2,485 PSI)
not pass through control valve
Return circuit automatically
2-way circuit attachment A mode or When shipped from factory:
becomes circuit which passes
(such as crusher) E mode 20.1 MPa (205 kgf/cm2, 2,911 PSI)
through control valve

Adjusting Oil Flow

Depending on the attachment, it is necessary to change the oil flow in the service circuit.
For details of setting the oil flow, see "ATTACHMENT OPERATIONS (PAGE 6-13)".

Switching Between Breaker and General Attachment

If an attachment is installed as an option, and the mode is set to B mode:
(1) The system is set to the breaker operation circuit (1-way circuit).
(2) The hydraulic oil flowing to the breaker circuit flows to the additional filter for the breaker.
(3) The relief pressure valve is set to low pressure.
Set pressure when machine is shipped from factory: 17.2 MPa (175 kgf/cm2, 2,490 PSI)
(4) It is possible to use the selector mode to adjust the maximum oil flow.

If an attachment is installed as an option, and the mode is set to A or E mode:

(1) The system is set to the crusher operation circuit (2-way circuit).
(2) The hydraulic oil flowing to the crusher circuit does not flow to the additional filter for the breaker.
(3) The relief pressure valve is set to high pressure.
Set pressure when machine is shipped from factory: 20.1 MPa (205 kgf/cm2, 2,911 PSI)
(4) It is possible to use the selector mode to adjust the maximum oil flow.

6-7
.

MACHINE READY FOR ATTACHMENT ATTACHMENTS AND OPTIONS

Hydraulic Circuit Connection

When connecting the attachment, connect the hydraulic circuit as
follows.
1. Remove blind plug (1) at the end of the stop valve piping.
(Two spots on the left and right)
Be careful not to lose or damage any part that has been
removed.

2. Connect attachment piping (2) provided by the attachment

maker to the part from which the plug was removed Step 1.
For the mouthpiece size and accumulator add-on, the action to
take differs according to the attachment manufacturer, so
please consult your Komatsu distributor.

6-8
.

ATTACHMENTS AND OPTIONS MACHINE READY FOR ATTACHMENT

Oil Flow Path

The direction of operation of the pedal and the path of the oil flow is as shown in the diagram below.

When the front of the pedal is depressed, oil flows to the piping on the left side of the work equipment; when the rear
of the pedal is depressed, oil flows to the piping on the right side of the work equipment. (When a breaker is installed,
only the front of the pedal can be used.)

6-9
.

MACHINE READY FOR ATTACHMENT ATTACHMENTS AND OPTIONS

Replace Additional Breaker Filter Element

WARNING
The parts and oil are at high temperature after the engine is stopped,
and may cause burns. Wait for the temperature to go down before
starting the work.

Prepare a container to catch the oil.

1. Place a container under the filter element to catch the oil.
2. Remove plug (3) from filter case (1) and drain the oil.
3. Turn filter case (1) to the left to remove it, then take out element
(2).
4. Clean the removed parts, then install new element (2) and
O-ring (4).
5. When installing, bring the case into contact with the filter
holder, then tighten a further 1/2 turns.

NOTICE
For details of the replacement interval for the element, "MAINTENANCE
INTERVAL FOR HYDRAULIC BREAKER (PAGE 4-17)".

6 - 10
.

ATTACHMENTS AND OPTIONS MACHINE READY FOR ATTACHMENT

ATTACHMENT REMOVAL AND INSTALLATION

Attachment Removal
1. Lower the attachment to the ground and stop the engine.
2. Turn the starting switch to the ON position (B), then set the lock
lever to the FREE position (F).
3. Operate each work equipment control lever and the
attachment control pedal back and forth, left and right at full
stroke 2 to 3 times to eliminate the internal pressure in the
hydraulic circuit.

4. Loosen slowly oil filler cap (F) on top of the hydraulic tank to
eliminate the internal pressure in the hydraulic circuit.

5. After checking that the oil has cooled down, turn the rotor on
the stop valve installed to the piping for the inlet port and outlet
port on the side face of the arm to the LOCK position (L).
6. Remove the hoses on the attachment side. Install the plugs to
the two outlets.
The plugs are used to prevent the attachment from incorrect
operation caused by mixing in of foreign matter. After the plugs
are correctly installed, store the attachment.

6 - 11
.

MACHINE READY FOR ATTACHMENT ATTACHMENTS AND OPTIONS

7. Pull out the mounting pins (2 places), remove the attachment,

then install the bucket.
For details of the procedure for installing the bucket, see
"BUCKET REPLACEMENT AND INVERSION (PAGE
3-119)".
8. After installing the bucket, check the oil level in the hydraulic
tank.

Attachment Installation
1. Remove the bucket.
For bucket dismounting procedure, see "BUCKET REPLACEMENT AND INVERSION (PAGE 3-119)".
2. Place the attachment in a horizontal position, then install to the
arm with pin (A) and then pin (B).

3. After confirming low oil temperature, remove the plug from the
outlet and inlet port respectively.
Take care that no dust, mud etc. adheres to the hose
mousepiece portions.
If O-ring is damaged, replace it with a new one.
4. Connect the hose at the attachment side.
When doing this, check the direction of flow of the oil and be
careful not to make any mistake.
5. Turn the rotor on the stop valve installed to the piping for the
inlet port and outlet port on the side face of the arm to the FREE
position (F).
6. After installing the attachment, check the oil level in the
hydraulic tank.

6 - 12
.

ATTACHMENTS AND OPTIONS MACHINE READY FOR ATTACHMENT

ATTACHMENT OPERATIONS
WARNING
Do not rest the foot on the pedal and depress it, when the auto deceleration switch is in ON position. The engine speed rises
all of sudden and the attachment will move suddenly and cause serious damage or injury.
Do not put your foot on the pedal except when operating the pedal. If rest your foot is the pedal during operations, and it is
depressed by accident, the attachment may move suddenly and cause serious damage or injury.

Operate the attachment as follows.

When Using Breaker

With the working mode set to B mode, set the lock pin to FREE
position (a) for the front only, and depress the front of the pedal to
actuate the breaker.
1. Set the working mode to B mode.
2. When monitor select switch (1) is pressed, the screen changes
to screen (A), so select the appropriate oil flow for the breaker
that is installed (300 liter (79.26 US gal)/min., 220 liter (58.12
US gal)/min., 140 liter (36.99 US gal)/min.), then press input
confirmation switch (2).
3. The screen changes to screen (B), so if any fine adjustment is
needed, press UP switch (3) or DOWN switch (4) to move the
bar graph showing the oil flow up or down, select the
appropriate oil flow, then press input confirmation switch (2).
One segment on the scale can change the oil flow by
approx. 20 liter (5.28 US gal)/min.
If no fine adjustment is needed, simply press input
confirmation switch (2).
Even when the starting switch is turned OFF, the oil flow set
by the above operation remains as the set value when the
engine is started next.

Precautions when using

Check that the stop valve is at the FREE position.
Check that the working mode is B mode.
For details of the path of the oil, see "HYDRAULIC CIRCUIT
(PAGE 6-7)".
When considering whether it is necessary to install an
accumulator for the attachment circuit, contact the
attachment manufacturer and then decide.
For other precautions when handling the breaker, follow the
instruction manual from the breaker manufacturer and use
the breaker correctly.

6 - 13
.

MACHINE READY FOR ATTACHMENT ATTACHMENTS AND OPTIONS

The deterioration of the hydraulic oil when using the breaker is

much faster than for normal operations, so reduce the
maintenance interval for the hydraulic oil and element.
For details, see "MAINTENANCE INTERVAL FOR
HYDRAULIC BREAKER (PAGE 4-17)".

When Using General Attachment Such as Crusher

With the working mode set to A mode or E mode, set the lock pin
to FREE position (b) for both the front and rear, and depress the
front or rear of the pedal to actuate the attachment.
1. Set the working mode to A mode or E mode.
2. When monitor select switch (1) is pressed, the screen changes
to screen (C), so press UP switch (3) or DOWN switch (4) to
move the bar graph showing the oil flow up or down, select the
appropriate oil flow, then press input confirmation switch (2).
The default setting is the full oil flow (approx. 550 liter
(145.31 US gal)/min.).
Even when the starting switch is turned OFF, the oil flow set
by the above operation remains as the set value when the
engine is started next.

Precautions when using

Check that the stop valve is at the FREE position.
Check that the working mode is A mode or E mode.
For details of the path of the oil, see "HYDRAULIC CIRCUIT
(PAGE 6-7)".
For other precautions related to the handling of attachment,
follow the explanation in the operation manual provided by
the attachment manufacturer to operate the attachment
correctly.

6 - 14
.

ATTACHMENTS AND OPTIONS MACHINE READY FOR ATTACHMENT

LONG TERM STORAGE

If the equipment is not to be used for a long time, do as follows.
Set the stop valve in the LOCK condition.
Install the plug and O-rings to the valves.
Set the lock pin at the LOCK position.
If there is no breaker or general attachment installed, operating the pedal may cause overheating and other
problems.

SPECIFICATIONS
Hydraulic specifications
Max. flow at merge: 270 x 2 liters / min.
Safety valve relief set pressure for service valve
A port: 21.6 MPa (220 kgf/cm2, 3,120 PSI) (except B mode)
B port: 24.5 MPa (250 kgf/cm2, 3,550 PSI) (except B mode)
Safety valve cracking pressure for service valve
A port: 17.2 MPa (175 kgf/cm2, 2,490 PSI) (except B mode)
B port: 20.1 MPa (205 kgf/cm2, 2,910 PSI) (except B mode)
Safety valve relief set pressure for service valve: 21.6 MPa (220 kgf/cm2, 3,120 PSI) (B mode)
Safety valve cracking pressure for service valve: 17.2 MPa (175 kgf/cm2, 2,490 PSI) (B mode)

6 - 15
.

ATTACHMENT GUIDE ATTACHMENTS AND OPTIONS

ATTACHMENT GUIDE
WARNING
Please read the instruction manual for the attachment and the sections of this manual related to attachments and options.
When installing any attachment or option, there may be problems with safety, so please contact your Komatsu distributor
before installing.
Installing attachments or options without consulting your Komatsu distributor may not only cause problems with safety, but
may also have an adverse effect on the operation of the machine and the life of the equipment.
Any injuries, accidents, or damage resulting from the use of unauthorized attachments or options will not be the responsibility
of Komatsu.

ATTACHMENT COMBINATIONS
WARNING
Depending on the type or combination of work equipment, there is danger that the work equipment may hit the cab or machine
body.
When using unfamiliar work equipment for the first time, check before starting if there is any danger of interference, and operate
with caution.

PC400, PC400LC
This table lists the combination of attachments which can be installed to the long arm (standard), short arm and
extension arm.
{: Can be used
U: Can be used only for light duty work
: Cannot be used

NOTICE
When the long arm is equipped, if the bucket is pulled in to the machine body, the arm interferes with the body. Operate the long
arm carefully.
When the boom is fully lowered during oblique digging, the boom interferes with the undercarriage. Operate the boom
carefully.

Categories of use
For general digging: Digging or loading sand, gravel, clay etc.
For light duty digging: Digging or loading dry, uncaked earth and sand, mud etc.
For loading work: Loading dry, loose earth and sand
For digging or loading hard soil or soft rock, it is recommended that the strengthened bucket with high durability
and high wear resistance be employed.

6 - 16
.

ATTACHMENTS AND OPTIONS ATTACHMENT GUIDE

The items marked * are for when the side cover is installed.

Standard boom HD boom

7,000 mm 7,000 mm
Bucket
Opening (22' 12") (22' 12")
Capacity
Bucket name 3 width Use Standard Short Ultra Semi-long Long HD
m
mm arm arm short arm arm arm arm
(cu.yd)
(ft in) 3.4 m 2.9 m 2.4 m 4.0 m 7.8 m 3.4 m
(11' 2") (9' 6") (7' 10") (13' 1") (25' 7") (11' 2")
1.3 1,120 Narrow width
*Narrow { { { { {
(1.7) (3' 8") excavation
1.6 1,270 Narrow width
*Narrow { { { ∆ ∆
(2.1) (4' 2") excavation
1.9 1,475 General
*Standard { { {
(2.5) (4' 10") excavation
*Light-duty 2.1 1,565
Loading ∆ ∆ ∆
work (2.7) (5' 2")
Light-duty 2.2 1,715
Loading ∆ ∆ ∆
work (2.9) (5' 8")
1.9 1,440 Excavating
*Rock { { { {
(2.5) (4' 9") soft rock
2.1 1,560 Excavating
*Rock ∆ ∆ ∆ ∆
(2.7) (5' 1") soft rock
1.1 1,250 Excavating
Ripper { { { {
(1.4) (4' 1") rock
Single-shank
- - Ripping rock { { { {
ripper

PC450, 450LC
This is the combination table for attachments installed to the standard HD arm.

The items marked * are for when the side cover is installed.

Capacity Opening width Standard arm

Name Use
m3 (cu.yd) mm (ft in) 3.4m (11 ft 2 in)
*Rock (standard) bucket 1.9 (2.5) 1,420 (4' 8") General excavation {
*Rock (large) bucket 2.1 (2.7) 1,560 (5' 1") For large-scale excavation {
Ripper bucket 1.1 (1.4) 1,250 (4' 1") Excavating rock {
Single-shank ripper - - Ripping rock {

NOTICE
When the boom is fully lowered during oblique digging, the boom interferes with the undercarriage. Operate the boom carefully.

6 - 17
.

RECOMMENDED ATTACHMENT OPERATIONS ATTACHMENTS AND OPTIONS

RECOMMENDED ATTACHMENT OPERATIONS

Below described are instructions which must be followed without fail when doing the work using a hydraulic
excavator equipped with an attachment.

NOTICE
Select the optimum model of attachment for a hydraulic excavator on which it is to be mounted.
Depending on machine models of hydraulic excavator, the kind of attachments or the model of specific attachments that can
be mounted will vary. Hence, consult your Komatsu distributor for the selection of optimum attachments.

HYDRAULIC BREAKER

Main Applications
Crushed rock
Demolition work
Road construction
This attachment can be used for a wide range of applications
including demolition of buildings, breaking up road surfaces or
slag, tunnel work, rock crushing and breaking operations in
quarries.

Keep the chisel pushed perpendicularly against the impact surface

when carrying out breaking operations.

When applying impact, push the chisel against the impact surface
and operate so that the chassis rises approx. 5 cm (2 in) off the
ground. Do not let the machine come further off the ground than
this amount.

6 - 18
.

ATTACHMENTS AND OPTIONS RECOMMENDED ATTACHMENT OPERATIONS

When applying continuous impact to the same impact surface, if

the chisel does not penetrate or break the surface within 1 minute,
change the point of impact and carry out breaking operations
closer to the edge.

The direction of penetration of the chisel and the direction of the

breaker body will gradually move out of line with each other, always
adjust the bucket cylinder to keep them aligned.

Always keep the chisel pressed against the impact surface

properly to prevent using the impact force when there is no
resistance.

Prohibited Works
To ensure that the machine has a long life, and to ensure that
operations are carried out in safety, do not operate the machine in
any of the following ways.
Do not operate all cylinders to the end of their strokes. Always
leave approx. 5 cm (2 in) to spare.
Using the mount to gather in pieces of rock

6 - 19
.

RECOMMENDED ATTACHMENT OPERATIONS ATTACHMENTS AND OPTIONS

Operations using the swing force

Moving the chisel while carrying out impacting operations

Holding the chisel horizontal or pointed up when carrying out

impacting operations

Twisting the chisel when it has penetrated the rock

Pecking operations

6 - 20
.

ATTACHMENTS AND OPTIONS RECOMMENDED ATTACHMENT OPERATIONS

Extending the bucket cylinder fully and thrusting to raise the

machine off the ground

Greasing
Supply grease in the correct position.

NOTICE
If the breaker is greased in an improper posture, it is filled with more grease
than necessary. As a result, soil and sand will enter the hydraulic circuit
and can damage the hydraulic components, while the breaker is in use.
Therefore, be sure to grease the breaker, holding it in the right posture.

6 - 21
.

7-1
.

EXPLANATION OF COMPONENTS LOADING SHOVEL

EXPLANATION OF COMPONENTS
SWITCHES

(1) Rotating lamp switch (if equipped) (8) Alarm buzzer stop switch
(2) Bottom dump switch (9) Swing lock switch
(3) Horn switch (10) Machine push-up switch
(4) Cigarette lighter (11) Swing brake cancel switch
(5) Starting switch (12) Emergency pump drive switch
(6) Fuel control dial (13) Room lamp switch
(7) Lamp switch

7-2
.

LOADING SHOVEL EXPLANATION OF COMPONENTS

Rotating Lamp Switch (If Equipped)

For details of this switch, see "SWITCHES (PAGE 3-30)" in the OPERATION section.

Bottom Dump Switch

This switch (2) is used to open and close the front bucket.
If the button at the tip of the left work equipment control lever is
depressed, the bucket will close.

If the button at the tip of the right work equipment control lever is
depressed, the front bucket will open.

Horn Switch
When switch (3) on the right work equipment control lever is
pressed, the horn will sound.

Cigarette Lighter
For details of this switch, see "SWITCHES (PAGE 3-30)" in the OPERATION section.

Starting Switch
For details of this switch, see "SWITCHES (PAGE 3-30)" in the OPERATION section.

Fuel Control Dial

(with Auto-deceleration System)
For details of this switch, see "SWITCHES (PAGE 3-30)" in the OPERATION section.

Lamp Switch
For details of this switch, see "SWITCHES (PAGE 3-30)" in the OPERATION section.

7-3
.

EXPLANATION OF COMPONENTS LOADING SHOVEL

Alarm Buzzer Stop Switch

For details of this switch, see "SWITCHES (PAGE 3-30)" in the OPERATION section.

Swing Lock Switch

For details of this switch, see "SWITCHES (PAGE 3-30)" in the OPERATION section.

Machine Push-up Switch

For details of this switch, see "SWITCHES (PAGE 3-30)" in the OPERATION section.

Swing Parking Brake Release Switch

For details of this switch, see "SWITCHES (PAGE 3-30)" in the OPERATION section.

Emergency Pump Drive Switch

For details of this switch, see "SWITCHES (PAGE 3-30)" in the OPERATION section.

Room Lamp Switch

For details of this switch, see "SWITCHES (PAGE 3-30)" in the OPERATION section.

7-4
.

LOADING SHOVEL OPERATIONS

OPERATIONS
OPERATION OF WORK EQUIPMENT
WARNING
If the lever is operated in the deceleration range, the engine speed will suddenly rise. Operate the levers carefully.
If the work equipment control levers are operated quickly, the engine speed will suddenly rise. Operate the levers carefully.

The work equipment is operated with the left work equipment control lever and right work equipment control lever.
The left work equipment control lever operates the arm, swing, and bottom dump (CLOSE); the right work equipment
control lever operates the boom, bucket, and bottom dump (OPEN).
The relationship between the operation of the lever and the movement of the work equipment is as shown in the
diagram on the right.
When the lever is released, it returns to the HOLD position and the work equipment is held in position.
If the work equipment control levers are returned to the neutral position when the machine is stopped, even if the
fuel control dial is set to FULL, the auto-deceleration mechanism will act to reduce the engine speed to a
mid-range speed.

REMARK
If the key in the starting switch is turned ON within 15 seconds after stopping the engine, it is possible to lower the
work equipment to the ground by operating the levers.
In addition, the levers can also be operated to release any remaining pressure inside the hydraulic cylinder circuit
and to lower the boom after loading the machine on a trailer.

Arm operation
(A): Arm OUT
(B): Arm IN

Swing operation
(A): Swing to left
(B): Swing to right

7-5
.

OPERATIONS LOADING SHOVEL

Boom operation
(A): Boom RIASE
(B): Boom LOWER

Bucket operation
(A): Bucket DUMP
(B): Bucket CURL

Bottom dump operation

(A): OPEN
(B): CLOSE

7-6
.

LOADING SHOVEL OPERATIONS

PRECAUTIONS DURING OPERATION

WARNING
When the arm is pushed out to the front, the speed may suddenly
become slower when the arm is close to the perpendicular position.
Turning or operating the work equipment when working on slopes may
cause the machine to lose its balance and tip over, so avoid such
operations.
It is particularly dangerous to swing downhill when the bucket is loaded.
If such operations have to be carried out, pile soil to make platform (A)
on the slope to make the footing of the machine is horizontal as
possible.
Do not travel up or down steep slopes. There is danger that the machine
may turn over.

It is Prohibited to Use the Swing Force for Operations.

Do not use the swing force to compact soil or break earth mounds
or walls.
When swinging, do not dig the bucket teeth into the soil.
These operations will damage the work equipment.

It is Prohibited to Use the Travel Force for Operations.

Do not move off and excavate with the bucket left dug into the
ground.

7-7
.

OPERATIONS LOADING SHOVEL

Do not Carry Out Operations with the Hydraulic Cylinder at the End of its Stroke.
If the cylinder is operated to the end of its stroke during operations,
a large force will be brought to bear on the stopper inside the
cylinder, and this will reduce the service life of the machine, so
leave room (distance a) at the end of the stroke as far as possible.

It is Prohibited to Use the Dropping Force of the Bucket for Operations.

Do not use the dropping force of the bucket as a pickaxe, breaker,
or pile driver. This will bring excessive force to bear on the rear of
the machine, and will not only damage the machine, but is also
dangerous.

Be Careful of Stability when Swinging.

During swing operations, the stability of the machine differs to the
front, rear, left and right, and there is danger that itmay tip over.

It is Prohibited to Use the Tilt Operation for Digging.

Do not set the teeth vertically when the bucket is pulled in, and then
use the tilt operation to carry out digging.

7-8
.

LOADING SHOVEL OPERATIONS

It is Prohibited to Grip Rocks.

Do not use the bottom dump bucket to grip rocks.

It is Prohibited to Use the Bucket for Leaving Operations.

Using the rear bucket to carry out leveling operations will bring an
excessive force to bear on the work equipment, so do not use the
rear bucket in this way.

Be Careful not to Spill the Load.

When the bucket is fully loaded, do not raise the boom fully. If the
boom is raised fully, the load will spill to the rear and cause danger
to the operator.

Be Careful not to Hit the Undercarriage.

If the upper structure is set diagonally to the track frame when
carrying out digging operations, the work equipment will hit the
track links.

7-9
.

OPERATIONS LOADING SHOVEL

Scraping-down Operations are Prohibited.

Never use the front bucket of a bottom-dump bucket to scrap down
rocks or soil.

Digging Rocky Ground

Do not attempt to directly excavate hard rocky ground with the work equipment. It is better to excavate it after
breaking up by some other means. This will not only save the machine from damage but will make for better
economy.

Phenomena that do not Indicate Failure

Note that the following phenomena are not failures:
When starting or stopping the swing, noise will be emitted from the brake valve.
When going down a steep slope at low speed, a noise will be emitted from the travel motor.
The arm may sometimes stop when the bucket teeth become
more or less horizontal.

The bottom dump of the bucket may sometimes stop at the

bottom horizontal position when the bottom dump control lever
changes from open to close.

7 - 10
.

LOADING SHOVEL OPERATIONS

EXCAVATOR WORK
In addition to the following, it is possible to further increase the range of applications by using various attachments.

Shovel Work
This is suitable for digging a place which is higher than the
machine's position. It is most efficient if the arm s digging angle is
from vertical to 60i forward, and the arm cylinder is used effectively.

The top surface of part (1) in the diagram on the right is parallel to
the direction of the bucket teeth. Therefore, it is possible to know
the direction of the bucket teeth by watching the angle of this
surface.

Loading Work
In places where the swing angle is small, work efficiency can be
enhanced by locating the dump truck in a place easily visible to the
operator.
Loading is easier if the excavator is placed beside the dump truck
for loading. This way means more earth can be loaded more
effectively than by a loader working behind the truck.

7 - 11
.

PRECAUTIONS WHEN DISASSEMBLING MACHINE LOADING SHOVEL

PRECAUTIONS WHEN DISASSEMBLING MACHINE

RELEASING PRESSURE
When disassembling the machine or removing the piping during inspection or maintenance, always release the
pressure as follows.

Releasing Pressure from Work Equipment Circuit, Swing Circuit, Travel Circuit
WARNING
The hydraulic system is always under internal pressure, so when inspecting or replacing the piping or hoses, always release
the pressure in the circuit before starting. If the pressure is not released, high pressure oil may spurt out and cause serious
personal injury.
The parts and oil are at high temperature after the engine is stopped, and may cause serious burns. Wait for the temperature
to go down before starting the operation.
When the oil filler cap is removed, oil may spurt out, so turn the cap slowly to release the pressure before removing the cap.

1. Stop the machine on firm horizontal ground, lower the work

equipment to the ground as shown in the diagram on the right,
then stop the engine.
Set the lock lever at the FREE position.
2. Operate each work equipment control lever to the full stroke
within 5 - 6 seconds after stopping the engine.
Leave the starting switch at the ON position.
3. Remove the cap of the hydraulic tank.

4. Start the engine, run for approx. 10 seconds, then stop the engine again.
Do not run the engine at more than 1000 rpm.
Set the work equipment control levers to the HOLD position.
5. Operate each work equipment control lever to the full stroke within 5 - 6 seconds after stopping the engine.
Repeat Steps 4 - 5 three times.

Releasing Pressure in Accumulator Circuit

After stopping the engine, set lock lever (1) to the FREE position,
then operate each work equipment control lever 3 - 4 times to the
end of the stroke. After 1 minute, the internal pressure will be
relieved.
Do not loosen any piping until at least 1 minute has passed after
relieving the internal pressure.

7 - 12
.

LOADING SHOVEL TRANSPORTATION

TRANSPORTATION
MACHINE CONFIGURATION FOR TRANSPORT
This machine can be divided into four units for transportation.

Four Units for Transportation

(A) Upper Structure (C) Work Equipment

(B) Cab (D) Others

Posture for Each unit

Upper Structure + Undercarriage

Variable gauge specification machine
The value given in [ ] in the table below is the value when the track frame gauge has been retracted.

Item Unit PC400 PC400LC

A mm (ft in) 3,275 (10' 9") 3,275 (10' 9")
B mm (ft in) 5,850 (19' 2") 6,035 (19' 10")
3,490 (11' 5") 3,590 (11' 9")
Overall width mm (ft in)
[2,990 (9' 10")] [2,990 (9' 10")]
Weight kg (lb) 25,170 (55,500) 26,270 (27,925)

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TRANSPORTATION LOADING SHOVEL

Fixed gauge specification machine

Item Unit PC400 PC400LC

A mm (ft in) 3,275 (10' 9") 3,275 (10' 9")
B mm (ft in) 5,850 (19' 2") 6,035 (19' 10")
Overall width mm (ft in) 3,340 (10' 11") 3,440 (11' 3")
Weight kg (lb) 24,000 (52,920) 25,000 (55,125)

Upper Structure + Undercarriage (without cab)

Variable gauge specification machine
The value given in [ ] in the table below is the value when the track frame gauge has been retracted.

Item Unit PC400 PC400LC

A mm (ft in) 3,115 (10' 3") 3,115 (10' 3")
B mm (ft in) 5,850 (19' 2") 6,035 (19' 10")
3,490 (11' 5") 3,590 (11' 9")
Overall width mm (ft in)
[2,990 (9' 10")] [2,990 (9' 10")]
Weight kg (lb) 24,890 (54,882) 25,990 (57,308)

Fixed gauge specification machine

Item Unit PC400 PC400LC

A mm (ft in) 3,115 (10' 3") 3,115 (10' 3")
B mm (ft in) 5,850 (19'2") 6,035 (19' 10")
Overall width mm (ft in) 3,340 (10' 11") 3,440 (11' 3")
Weight kg (lb) 23,720 (52,303) 24,720 (61,123)

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LOADING SHOVEL TRANSPORTATION

Cab

Item Unit PC400, PC400LC

A mm (ft in) 1,670 (5' 6")
B mm (ft in) 1,840 (6')
Overall width mm (ft in) 1,000 (3' 3")
Weight kg (lb) 280 (617)

Work Equipment
Boom cylinder

Item Unit PC400

A mm (ft in) 2,700 (8'10")
Weight kg (lb) 380 X 2 (838 X 2)

Bucket cylinder

Item Unit PC400-7

A mm (ft in) 2,200 (7' 3")
Weight kg (lb) 230 X 2 (507 X 2)

Boom + Arm

Item Unit PC400

A mm (ft in) 6,800 (22'4")
B mm (ft in) 1,900 (6'3")
Width mm (ft in) 1,000 (3'3")
Weight kg (lb) 4,000 (8,820)

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TRANSPORTATION LOADING SHOVEL

Bucket

Item Unit PC400

A mm (ft in) 2,100 (6' 11")
B mm (ft in) 2,100 (6' 11")
Width mm (ft in) 1,970 (6' 6")
Weight kg (lb) 3,400 (11' 2")

Others
Counterweight

Item Unit PC400, PC400LC

A mm (ft in) 1,145 (3' 9")
B mm (ft in) 2,995 (9' 10")
C mm (ft in) 970 (3' 2")
Weight kg (lb) 9,230 (20,352)

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LOADING SHOVEL MAINTENANCE

MAINTENANCE
CHECK BEFORE STARTING
Always check the items in this section before starting the engine each day.

Check Oil Level in Hydraulic Tank, Add Oil

WARNING
The parts and oil are at high temperature immediately after the engine is stopped, and may cause burns. Wait for the
temperature to go down before starting the work.
When removing the oil filler cap, turn it slowly to release the internal pressure, then remove it.

1. If work equipment is not in the condition shown in diagram on

the right, start engine, run at low idle, retract the arm and
bucket cylinders, then lower the boom, set bucket teeth in
contact with the ground, and stop the engine.
2. Within 15 seconds after stopping the engine, turn starting
switch to the ON position, and operate the control levers (work
equipment, travel) in each direction to release the internal
pressure.

3. Check sight gauge (G). The oil level should be between the H
and L marks.

NOTICE
Do not add oil above the H line. This will damage the hydraulic circuit or
cause the oil to spurt out. If oil has been added to above the H level, stop
the engine and wait for the hydraulic oil to cool down, then drain the excess
oil from drain plug (P).

4. If the level is below the L mark, add oil through oil filler (F) at the
top of the hydraulic tank.

REMARK
The oil level will vary depending upon the oil temperature.
Accordingly, use the following as a guide:
Before starting operation: Between H and L levels
(Oil temperature 10 to 30°C (50 to 86°F))
Normal operation: Around H level
(Oil temperature 50 to 80°C (122 to 176°F))

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MAINTENANCE LOADING SHOVEL

EVERY 10 HOURS MAINTENANCE

LUBRICATTING
1. Set to the greasing posture below, lower the work equipment to the ground, then stop the engine.
2. Using a grease pump, pump in grease through the grease fittings shown by arrows.
3. After greasing, wipe off any old grease that was pushed out.

(1) Boom cylinder foot pin (2 places) (10) Boom-Arm coupling pin (arm side) (2 places)
(2) Bucket cylinder rod end (2 places) (11) Bucket cylinder rod end, link connection pin
(3) Bucket-Link coupling pin (2 places) (4 places)
(4) Bottom dump cylinder foot pin (2 places) (12) Boom centralized greasing block (10 places)
(5) Arm-Bucket coupling pin (2 places) Boom foot pin
(6) Link coupling pin (2 places) Arm cylinder foot pin
(7) Bucket hinge pin (2 places) Boom cylinder rod end
(8) Bottom dump cylinder rod end (2 places) Bucket cylinder rod end
(9) Arm cylinder rod end (1 place) Boom-Arm coupling pin (boom side)

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LOADING SHOVEL SPECIFICATION

SPECIFICATION
PC400-7 LOADING SHOVEL
PC400LC-7 LOADING SHOVEL

Item Unit PC400-7 PC400LC-7

(Variable gauge 43,100 44,200
Operating specification) kg (95,036) (97,461)
weight (Fixed gauge (lb) 41,900 42,900
specification) (92,390) (94,595)
m3 2.6 2.6
Bucket capacity
(cu.yd) (3.4) (3.4)
Name of engine - Komatsu SAA6D125E-3 diesel engine
kW/rpm 335/1,850 335/1,850
Engine horsepower
(HP/rpm) (449/1,850) 449/1,850)
mm 8,455 8,455
A Overall length
(ft in) (27'9") (27'9")
mm 4,400 4,400
B Overall height
(ft in) (14'5") (14'5")
(Variable gauge 3,490 3,590
specification) mm (11'5") (11'9")
C Overall width
(Fixed gauge (ft in) 3,340 3,440
specification) (10'11") (11'3")
mm 600 700
D Track width
(ft in) (1'12") (2'4")
mm 3,250 3,250
E Height of cab
(ft in) (10'8") (10'8")
mm 3,645 3,645
F Tail swing radius
(ft in) (11'12") (11'12")
mm 5,055 5,055
G Length of track
(ft in) (16'7") (16'7")
mm 4,020 4,350
H Tumbler center distance
(ft in) (13'2") (14'3")
mm 685 685
Min. ground distance
(ft in) (2'3") (2'3")
km/h 3.0/4.4/5.5 3.0/4.4/5.5
Travel speed [Lo / Middle / Hi]
(MPH) (1.9/2.7/3.4) (1.9/2.7/3.4)
Swing speed rpm 9.1 9.1

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SPECIFICATION LOADING SHOVEL

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.

LOADING SHOVEL COMBINATION OF WORK EQUIPMENT

COMBINATION OF WORK EQUIPMENT

WARNING
Depending on the type or combination of work equipment, there is danger that the work equipment may hit the cab or machine
body.
When using unfamiliar work equipment for the first time, check before starting if there is any danger of interference, and operate
with caution.

COMBINATION OF WORK EQUIPMENT

Select the combination of boom, arm, and bucket from the combinations shown in the table below.

Boom 4.0 m(1' 4")

Work equipment

Arm 2.9 m(11")

Bucket capacity 2.6 m3 (3.4 cu.yd)
Bucket width 1900 mm(6' 3")
2.1 x
Loosen specific gravity of soil
1.8 o
to be handled
1.5 o

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COMBINATION OF WORK EQUIPMENT LOADING SHOVEL

Working Range Diagram

PC400-7, PC400LC-7 LOADING SHOVEL

Working ranges Unit
(With bucket link)
mm 8,660
A Max. digging radius
(ft in) (28' 5")
mm 8,375
B Max. digging reach at ground level
(ft in) (27' 6")
mm 10,190
C Max. digging height
(ft in) (33' 5")
mm 3,045
D Max. digging depth
(ft in) (9' 12")
mm 4,850
E Min. digging reach at ground level
(ft in) (15' 11")
mm 4,535
F Min. swing radius of work equipment
(ft in) (14' 11")

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INDEX

INDEX

<A> <G>
Accumulator 3- 70 General Operation Information 3-112
Air Conditioner Controls 3- 47 General Precautions for Safety 6- 2
Ashtray 3- 46 Precautions when Removing or
Attachment Guide 6- 16 Installing 6- 2
Attachment Combinations 6- 16 Precautions when Selecting 6- 2
Auxiliary Electric Power 3- 66 Precautions when Using 6- 2
Read the Instruction Manual
<B> Thoroughly 6- 2
Breaking-In The New Machine 1- 7 Grease Gun Holder 3- 69
Bucket Replacement and Inversion 3-119
<H>
<C> Handling Oil, Fuel, Coolant, and
Cap with Lock 3- 44 Performing Oil Clinic 4- 4
Cold Weather Operation 3-139 Hot and Cool Box 3- 45
After Cold Weather Season 3-142
After Daily Work Completion 3-142 <I>
Cold Weather Operation Information 3-139 Introduction 1- 7
Combination of Work Equipment 7- 21
Combination of Work Equipment 7- 21 <L>
Control Levers and Pedals 3- 35 Locking 3-124
Controller 3- 68 Long Term Storage 3-143
Controls and Gauges 3- 3 After Storage 3-143
Before Storage 3-143
<D> During Storage 3-143
Detailed Controls and Gauges 3- 5 Starting Machine After Long-Term
Directions of Machine 1- 7 Storage 3-144
Door Lock 3- 43 Lubricants, Fuel and Coolant
Specifications 4- 9
<E>
Electric System Maintenance 4- 7 <M>
Emergency Exit from Operator's Cab 3- 43 Machine Inspection After Daily Work 3-123
Engine, After Starting 3- 90 Machine Operation 3-100
Engine, Before Starting 3- 71 Machine Operations and Controls 3- 71
Engine Serial No. Plate and Its Location 1- 8 Machine Ready for Attachment 6- 3
Engine, Check After Shut Off 3-123 Attachment Operations 6- 13
Engine, Starting 3- 86 Attachment Removal and Installation 6- 11
Engine, Stopping the 3- 99 Hydraulic Circuit 6- 7
Escape from Mud 3-116 Locations 6- 3
Excavator Work 7- 11 Long Term Storage 6- 15
Explanation of Components 7- 2 Specifications 6- 15
Machine View Illustrations 3- 2
<F> Machine, Steering the 3-104
Foreword 1- 2 Magazine Box 3- 46
Fuse 3- 67 Maintenance 7- 17
Fusible Link 3- 68 Check Before Starting 7- 17
Every 10 Hours 7- 18

8-1
.

INDEX

Maintenance Information 4- 2 Safety Labels 2- 5

Maintenance Procedure 4- 18 Safety Machine Operation 2- 20
Check Before Starting 4- 44 Battery 2- 29
Every 50 Hours 4- 45 Lifting Objects with Bucket 2- 32
Every 250 Hours 4- 46 Operation 2- 22
Every 500 Hours 4- 53 Starting Engine 2- 20
Every 1000 Hours 4- 66 Towing 2- 31
Every 2000 Hours 4- 73 Transportation 2- 28
Every 4000 Hours 4- 76 Safety Maintenance Information 2- 33
Every 5000 Hours 4- 78 Service Meter Location 1- 9
Every 8000 Hours 4- 80 Specification 7- 19
Initial 250 Hours (First 250 Hours Only) 4- 18 Specifications 5- 2
When Required 4- 19 Sun Roof 3- 38
Maintenance Schedule 4- 15 Swinging 3-106
Maintenance Interval for Hydraulic Switches 3- 30
Breaker 4- 17 Switches 7- 2
Maintenance Schedule Chart 4- 15
Monitoring System 3- 5 <T>
Tightening Torque Specifications 4- 13
<O> Tightening Torque List 4- 13
Operation of Work Equipment 7- 5 Tool Box 3- 69
Operations 7- 5 Transportation 3-125
Outline of Service 4- 4 Lifting Machine 3-134
Overall Machine View 3- 2 Loading and Unloading with Trailer 3-126
Precautions for Transportation 3-125
<P> Transportation Posture 3-136
Parking Machine 3-122 Transportation 7- 13
Precautions During Operation 7- 7 Machine Configuration for Transport 7- 13
Precautions when Disassembling Traveling on Slopes 3-114
Machine 7- 12 Troubles and Actions 3-145
Releasing Pressure 7- 12 Battery, Discharged 3-149
Product Identification Number Lightweight Towing Hole 3-148
(PIN)/Machine Serial No. Plate 1- 8 Other Trouble 3-153
Product Information 1- 8 Phenomena That are Not Failures 3-146
Prohibited Operations 3-110 Running Out of Fuel 3-145
Severe Job Condition 3-148
<R> Towing the Machine 3-147
Radio 3- 61
Recommended Applications 3-117 <W>
Recommended Attachment Operations 6- 18 Wear Parts 4- 8
Hydraulic Breaker 6- 18 Wear Parts List 4- 8
Windshield 3- 38
<S> Work Equipment Controls and Operations 3-107
Safety Critical Parts 4- 14 Working Mode 3-109
Safety Critical Parts List 4- 14
Safety Information 1- 5 <Y>
Safety Information 2- 2 Your Machine Serial Numbers And
Safety Information 2- 11 Distributor 1- 9
Safety Labels 2- 4
Location of Safety Labels 2- 4

8-2
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PC400,400LC,450,450LC-7 GALEO HYDRAULIC EXCAVATOR

Form No. PEN00036-03

©
2006 KOMATSU
All Rights Reserved
Printed in Japan 07-06