Komatsu WA20-2 Manual

WA20 -2,WA30 -5
WA40 -3,WA50 -3
WHEEL LOADER
SERIAL NUMBERS   and up
NOTICE
Komatsu has Operation & Maintenance Manuals written in
some other languages. If a foreign language manual is
necessary, contact your local distributor for availability.
Unsafe use of this machine may cause serious injury
or death. Operators and maintenance personnel
must read this manual before operating or maintain-
ing this machine. This manual should be kept near the
machine for reference and periodically reviewed
by all personnel who will come into contact with it. 
WA20 - 11270
WA30 - 18970
WA40 - 13530
WA50 - 20642
SEAM010700

0-1
1. FOREWORD
This manual provides rules and guidelines which will help you use this machine safely and
effectively. Keep this manual handy and have all personnel read it periodically. If this manual has been
lost or has become dirty and can not be read, request a replacement manual from Komatsu or your
Komatsu distributor.
If you sell the machine, be sure to give this manual to the new owners.
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.
This manual may contain attachments and optional equipment that are not available in your area.
Consult Komatsu or your Komatsu distributor for those items you may require.
WARNING
‡ Improper operation and maintenance of this machine can be hazardous and could result in serious
injury or death.
‡ Operators and maintenance personnel should read this manual thoroughly before beginning
operation or maintenance.
‡ Some actions involved in operation and maintenance of the machine can cause a serious accident,
if they are not done in a manner described in this manual.
‡ The procedures and precautions given in this manual apply only to intended uses of the machine.
If you use your machine for any unintended uses that are not specifically prohibited, you must
be sure that it is safe for you and others. In no event should you or others engage in prohibited
uses or actions as described in this manual.
‡ Komatsu delivers machines that comply with all applicable regulations and standards of the
country to which it has been shipped. If this machine has been purchased in another country or
purchased from someone in another country, it may lack certain safety devices and specifications
that are necessary for use in your country. If there is any question about whether your product
complies with the applicable standards and regulations of your country, consult Komatsu or your
Komatsu distributor before operating the machine.
‡ The description of safety is given in SAFETY INFORMATION on page 0-2 and in SAFETY from page
1-1.
CALIFORNIA
Proposition 65 Warning
Diesel engine exhaust and some of its
constituents are known to the State
of California to cause cancer, birth
defects, and other reproductive
harm.

0-2
2. SAFETY INFORMATION
Most accidents are caused by the failure to follow fundamental safety rules for the operation and
maintenance of machines. To avoid accidents, read, understand and follow all precautions and warnings
in this manual and on the machine before performing operation and maintenance.
To identify safety messages in this manual and on machine labels, the following signal words are
used.
DANGER – This word is used on safety messages and safety labels where there is a high
probability of serious injury or death if the hazard is not avoided. These safety
messages or labels usually describe precautions that must be taken to avoid the
hazard. Failure to avoid this hazard may also result in serious damage to the
machine.
WARNING – This word is used on safety messages and safety labels where there is a
potentially dangerous situation which could result in serious injury or death if
the hazard is not avoided. These safety messages or labels usually describe
precautions that must be taken to avoid the hazard. Failure to avoid this hazard
may also result in serious damage to the machine.
CAUTION – This word is used on safety messages and safety labels for hazards which could
result in minor or moderate injury if the hazard is not avoided. This word might
also be word for hazards where the only result could be damage to the machine.
NOTICE – This word is used for precautions that must be taken to avoid actions which
could shorten the life of the machine.
Safety precautions are described in SAFETY from page 1-1.
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, you must be sure that you and others can do such procedures and actions safely and
without damaging the machine. If you are unsure about the safety of some procedures, contact your
Komatsu distributor.

0-3
3. INTRODUCTION
3.1 INTENDED USE
This machine is intended mainly for the following operations.
‡ Digging operations
‡ Leveling operations
‡ Pushing operations
‡ Loading operations
For details of the operating procedure, see “12.9 WORK POSSIBLE USING WHEEL LOADER”.
3.2 FEATURES
‡ Easy operation by HST mechanism
‡ High performance
‡ Each kind of safety devices is installed.
3.3 BREAKING IN THE MACHINE
Your Komatsu machine has been thoroughly adjusted and tested before shipment.
However, operating the machine under severe conditions at the beginning can adversely affect the
performance and shorten the machine life.
Be sure to break in the machine for the initial 100 hours (as indicated by the service meter.)
During breaking in:
‡ Idle the engine for 5 minutes after starting it up.
‡ Avoid operation with heavy loads or at high speeds.
‡ Avoid sudden starts, sudden acceleration, sudden steering and sudden stops except in cases of
emergency.
The precautions given in this manual for operating, maintenance, and safety procedures are only
those that apply when this product is used for the specified purpose. If the machine is used for a purpose
that is not listed in this manual, Komatsu cannot bear any responsibility for safety. All consideration of
safety in such operations is the responsibility of the user.
Operations that are prohibited in this manual must never be carried out under any circumstances.

0-4
4. LOCATION OF PLATES, TABLE TO ENTER
SERIAL NO. AND DISTRIBUTOR
4.1 MACHINE SERIAL NO. PLATE POSITION
4.1.1 WA20
Position of plate
This plate is on the center of the front frame on the right side of
the machine.
Position of stamp
This is stamped on the center of the front frame on the right side
of the machine.
4.1.2 WA30, 40, 50
Position of plate
This plate is on the center of the front frame on the right side of
the machine.
Position of stamp
This is stamped on the center of the front frame on the right side
of the machine.
4.2 ENGINE SERIAL NO. PLATE POSITION
Position of plate
This plate is on top of the engine cylinder head cover.
Position of stamp
This is stamped on the right side of the engine cylinder block as
seen from the fan.

0-5
Machine serial No.:
Engine serial No.:
Distributor name:
Address: Phone:
Service personnel for your machine:
4.3 TABLE TO ENTER SERIAL NO. AND DISTRIBUTOR
4. LOCATION OF PLATES, TABLE TO ENTER SERIAL NO. AND DISTRIBUTOR
REMARKS
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0-6
5. CONTENTS
1. Foreword ............................................................................................................................................. 0- 1
2. Safety information .............................................................................................................................. 0-2
3. Introduction .......................................................................................................................................... 0- 3
4. Location of plates, table to enter serial No. and distributor ........................................................ 0- 4
SAFETY
6. General precautions ............................................................................................................................ 1- 2
7. Precautions during operation ............................................................................................................ 1- 7
7.1 Before starting engine ............................................................................................................. 1- 7
7.2 Operating machine ................................................................................................................... 1- 9
7.3 Transportation ........................................................................................................................... 1-14
7.4 Battery ....................................................................................................................................... 1-15
7.5 Towing ....................................................................................................................................... 1-16
8. Precautions for maintenance ............................................................................................................. 1-17
8.1 Before carrying out maintenance ........................................................................................... 1-17
8.2 During maintenance ................................................................................................................ 1-21
8.3 Tires ............................................................................................................................................ 1-25
9. Position for attaching safety labels .................................................................................................. 1-27
OPERATION
10. General view ....................................................................................................................................... 2- 2
10.1 General view of machine ........................................................................................................ 2- 2
10.2 General view of controls and gauges .................................................................................... 2- 3
11. Explanation of components ............................................................................................................... 2- 4
11.1 Meter, lamps ............................................................................................................................. 2- 4
11.2 Switches ..................................................................................................................................... 2- 8
11.3 Control levers, pedals .............................................................................................................. 2-10
11.4 Cap with lock ............................................................................................................................ 2-14
11.5 Safety bar .................................................................................................................................. 2-14
11.6 Tilt hood ..................................................................................................................................... 2-15
11.7 Towing pin ................................................................................................................................ 2-15
11.8 Fuse ............................................................................................................................................ 2-15
11.9 Fusible link ................................................................................................................................ 2-16
11.10 Manual pocket ........................................................................................................................... 2-17
11.11 Connectors ................................................................................................................................ 2-17

0-7
5. CONTENTS 5. CONTENTS
12. Operation .............................................................................................................................................. 2-18
12.1 Check before starting engine .................................................................................................. 2-18
12.2 Starting engine .......................................................................................................................... 2-29
12.3 Operations and checks after starting engine ......................................................................... 2-32
12.4 Moving machine off .................................................................................................................. 2-34
12.5 Changing direction .................................................................................................................... 2-36
12.6 Turning ....................................................................................................................................... 2-36
12.7 Stopping machine ..................................................................................................................... 2-37
12.8 Operation of work equipment ................................................................................................. 2-38
12.9 Work possible using wheel loader .......................................................................................... 2-39
12.10 Precautions for operation ......................................................................................................... 2-43
12.11 Adjusting work equipment posture ........................................................................................ 2-45
12.12 Parking machine ........................................................................................................................ 2-46
12.13 Checks after completion of operation .................................................................................... 2-47
12.14 Stopping engine ........................................................................................................................ 2-48
12.15 Check after stopping engine .................................................................................................... 2-48
12.16 Locking ....................................................................................................................................... 2-48
12.17 Handling the tires ...................................................................................................................... 2-49
13. Transportation ..................................................................................................................................... 2-52
13.1 Loading, unloading work ......................................................................................................... 2-52
13.2 Precautions for loading ............................................................................................................ 2-53
13.3 Lifting machine .......................................................................................................................... 2-53
13.4 Precautions for transportation ................................................................................................. 2-56
13.5 Removing and installation of canopy ..................................................................................... 2-56
14. Cold weather operation ..................................................................................................................... 2-58
14.1 Precautions for low temperature ............................................................................................. 2-58
14.2 Precautions after completion of work .................................................................................... 2-60
14.3 After cold weather ..................................................................................................................... 2-60
15. Long-term storage .............................................................................................................................. 2-61
15.1 Before storage ........................................................................................................................... 2-61
15.2 During storage ........................................................................................................................... 2-61
15.3 After storage .............................................................................................................................. 2-61
16. Troubleshooting .................................................................................................................................. 2-62
16.1 When machine runs out of fuel .............................................................................................. 2-62
16.2 Towing the machine ................................................................................................................ 2-63
16.3 If battery is discharged ............................................................................................................. 2-66
16.4 Other trouble .............................................................................................................................. 2-70

0-8
5. CONTENTS 5. CONTENTS
MAINTENANCE
17. Guides to maintenance ...................................................................................................................... 3- 2
18. Outlines of service ............................................................................................................................. 3- 5
18.1 Outline of oil, fuel, coolant ...................................................................................................... 3- 5
18.2 Outline of electric system ........................................................................................................ 3- 8
19. Wear parts list ..................................................................................................................................... 3- 9
20. Use of fuel, coolant and lubricants according to ambient temperature ..................................... 3-10
21. Standard tightening torques for bolts and nuts ........................................................................... 3-14
21.1 Introduction of necessary tools ............................................................................................... 3-14
21.2 Torque list .................................................................................................................................. 3-16
22. Periodic replacement of safety critical parts .................................................................................. 3-17
23. Maintenance schedule chart .............................................................................................................. 3-24
23.1 Maintenance schedule chart .................................................................................................... 3-24
24. Service Procedure ............................................................................................................................... 3-27
24.1 Initial 250 hours service ........................................................................................................... 3-27
24.2 When required ........................................................................................................................... 3-28
24.3 Check before starting ................................................................................................................ 3-42
24.4 Every 50 hours service ............................................................................................................. 3-48
24.5 Every 250 hours service ........................................................................................................... 3-49
24.6 Every 500 hours service ........................................................................................................... 3-54
24.7 Every 1000 hours service ......................................................................................................... 3-57
24.8 Every 2000 hours service ......................................................................................................... 3-60
SPECIFICATIONS
25. Specifications ....................................................................................................................................... 4- 2
OPTIONS, ATTACHMENTS
26. Optional parts and attachments ....................................................................................................... 5- 2
27. Seat belt ............................................................................................................................................... 5- 3
27.1 Fastening and removing belt .................................................................................................. 5- 3
27.2 Adjust belt length ...................................................................................................................... 5- 4
27.3 Check seat belt and mounts .................................................................................................... 5- 4
28. Equipment with cab ............................................................................................................................ 5- 5
28.1 Switches ..................................................................................................................................... 5- 5
28.2 Rear window .............................................................................................................................. 5- 9
28.3 Check and maintenance ........................................................................................................... 5-10

1-1
SAFETY
WARNING
Read and follow all safety precautions. Failure to do so may result
in serious injury or death.
This safety section also contains precautions for optional equip-
ment and attachments.

1-2
6. GENERAL PRECAUTIONS  WARNING: For reasons of safety, always
follow these safety precautions.
A0055010
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.
‡ Do not operate the machine if you are not feeling well, or if you are taking medicine which will
make you sleepy, or if you have been drinking. Operating in such a condition will adversely affect
your judgement and may lead to an accident.
‡ When working with another operator or a person on worksite traffic duty, be sure all personnel
understand all hand signals that are to be used.
SAFETY FEATURES
‡ Be sure all guards and covers are in their proper position. Have guards and covers repaired if
damaged.
Proper position ➞See “12.1.1 WALK-AROUND CHECK”.
‡ Use safety features such as the safety lock lever and seat belts properly.
‡ NEVER remove any safety features. ALWAYS keep them in good operating condition.
Safety lock lever ➞See “12.12 PARKING MACHINE”.
‡ Improper use of safety features could result in serious bodily injury or death.
CLOTHING AND PERSONAL PROTECTIVE ITEMS
‡ Avoid loose clothing, jewelry, and loose long hair. They can catch on controls or in moving parts
and cause serious injury or death. Also, do not wear oily clothes because they are flammable.
‡ Wear a hard hat, safety glasses, safety shoes, mask or gloves when operating or maintaining the
machine. Always wear safety goggles, hard hat and heavy gloves if your job involves scattering
metal chips or minute materials - this is so particularly when driving pins with a hammer and when
cleaning the air cleaner element with compressed air.
Check also that there is no one near the machine.
‡ Check the function of all protective equipment before use.
Cleaning of air cleaner element ➞See “24.2 WHEN REQUIRED” in service procedure.

1-3
6. GENERAL PRECAUTIONS
 WARNING: Failure to follow these safety precautions may lead
to a serious accident.
UNAUTHORIZED MODIFICATION
‡ Any modification made without authorization from Komatsu can create hazards.
‡ Before making a modification, consult your Komatsu distributor. Komatsu will not be responsible
for any injury or damage caused by any unauthorized modification.
ALWAYS APPLY LOCK WHEN LEAVING OPERATOR’S SEAT
‡ When standing up from the operator’s seat, always place the safety lock lever securely in the LOCK
position. If you accidentally touch the travel or swing lever when they are not locked, the work
equipment may suddenly move and cause serious injury or damage.
‡ When leaving the machine, lower the work equipment completely to the ground, set the safety
lock lever to the LOCK position, then stop the engine and use the key to lock all the equipment.
Always take the key with you.
Work equipment posture ➞See “12.12 PARKING MACHINE”.
Locks ➞See “12.16 LOCKING”.
MOUNTING AND DISMOUNTING
‡ NEVER jump on or off the machine. NEVER get on or off a moving machine.
‡ When getting on or off the machine, face the machine and use the handhold and steps.
‡ Never hold any control levers when getting on or off the machine.
‡ Maintain three-point contact (both feet and one hand or one foot and both hands), and be sure
that you are supported securely by the handrail and steps.
‡ If there is any oil, grease, or mud on the handholds or steps, wipe it off immediately. Always keep
these parts clean. Repair any damage and tighten any loose bolts.

1-4
FIRE PREVENTION FOR FUEL AND OIL
Fuel, oil, and antifreeze can be ignited by a flame. Fuel is particularly FLAMMABLE and can be
HAZARDOUS.
‡ Keep flame away from flammable fluids.
‡ Stop the engine and do not smoke when refueling.
‡ Tighten all fuel and oil tank caps securely.
‡ Refueling and oiling should be made in well ventilated areas.
‡ Keep oil and fuel in the determined place and do not allow unauthorized persons to enter.
PRECAUTIONS WHEN HANDLING AT HIGH TEMPERATURES
‡ Immediately after operations are stopped, the engine coolant, engine oil, and hydraulic oil are at
high temperatures, and are still under pressure. Attempting to remove the cap, drain the oil or
water, or replace the filters may lead to serious burns. Always wait for the temperature to go down,
and follow the specified procedures when carrying out these operations.
‡ Before removing the radiator cap, stop the engine and let the radiator cool. Turn the cap slowly
to release the internal pressure before removing the cap.
‡ As a result, oil may spurt out when the hydraulic tank cap is removed.
Always turn the cap slowly to release the internal pressure before removing the cap.
6. GENERAL PRECAUTIONS  WARNING: For reasons of safety, always follow these safety precautions.
A0055020
A0055030
A0055040
A0055050

1-5
 WARNING: Failure to follow these safety precautions may lead
to a serious accident. 6. GENERAL PRECAUTIONS
ASBESTOS DUST HAZARD PREVENTION
Asbestos dust can be HAZARDOUS to your health if it is inhaled.
If you handle materials containing asbestos fibers, follow these guidelines as given below:
‡ NEVER use compressed air for cleaning.
‡ Use water for cleaning to keep down the dust.
‡ Operate the machine with the wind to your back, whenever possible.
‡ Use an approved respirator if necessary.
CRUSHING OR CUTTING PREVENTION
‡ Do not enter, or put your hand or arm or any other part of your body between movable parts such
as between the work equipment and cylinders, or between the machine and work equipment.
If the work equipment is operated, the clearance will change and this may lead to serious damage
or personal injury.
FIRE EXTINGUISHER AND FIRST AID KIT
‡ Be sure fire extinguishers have been provided and know how to use them.
‡ Provide a first aid kit at the storage point.
‡ Know what to do in the event of a fire.
‡ Be sure you know the phone numbers of persons you should contact in case of an emergency.
A0055060
A0060760
A0055070

1-6
6. GENERAL PRECAUTIONS  WARNING: For reasons of safety, always follow these safety precautions.
PRECAUTIONS WHEN USING ROPS
If ROPS is installed, the ROPS must never be removed when operating the machine.
The ROPS is installed to protect the operator if the machine should roll over. It is designed not only
to support the load if the machine should roll over, but also to absorb the impact energy.
The Komatsu ROPS fulfills all of the regulations and standards for all countries, but if it is rebuilt
without authorization or is damaged when the machine rolls over, the strength will drop and it will
not be able to fulfill its function properly. It can only display its performance if it is repaired or
modified in the specified way.
When modifying or repairing the ROPS, always contact your Komatsu distributor.
Even if the ROPS is installed, it cannot show its full effect if the operator does not fasten the seat
belt properly. Always fasten the seat belt when operating.
PRECAUTIONS FOR ATTACHMENTS
‡ When installing and using an optional attachment, read the instruction manual for the attachment
and the information related to attachments in this manual.
‡ Do not use attachments that are not authorized by Komatsu or your Komatsu distributor. Use of
unauthorized attachments could create a safety problem and adversely affect the proper operation
and useful life of the machine.
‡ Any injuries, accidents, product failures resulting from the use of unauthorized attachments will
not be the responsibility of Komatsu.

1-7
7. PRECAUTIONS DURING
OPERATION  WARNING: Failure to follow these safety
precautions may lead to a serious accident.
7.1 BEFORE STARTING ENGINE
SAFETY AT WORKSITE
‡ Before starting operations, thoroughly check the area for any
unusual conditions that could be dangerous.
‡ Examine the shape of the ground and the quality of the soil
at the jobsite, and determine the optimum method of opera-
tion.
‡ When working on public roads, position flagmen and erect
barriers to ensure the safety of passing traffic and pedestrians.
‡ In places where there are buried objects, such as water pipes,
gas pipes, or pipes for high voltage cables, contact the com-
pany in charge to confirm the position of the buried object,
and be careful not to damage the object during operations.
‡ When working in water or when crossing sand banks, first
check the condition of the ground and the depth and speed of
flow of the water. Be sure not to exceed the permitted water
depth.
Permissible water depth ➞See “12.10 PRECAUTIONS FOR
OPERATION”.
FIRE PREVENTION
‡ Thoroughly remove wood chips, leaves, paper and other flam-
mable things accumulated in the engine compartment. They
could cause a fire.
‡ Check fuel, lubrication, and hydraulic systems for leaks. Have
any leaks repaired. Wipe up any excess oil, fuel or other
flammable fluids.
Check point ➞See “12.1.1 WALK-AROUND CHECK”.
‡ Be sure a fire extinguisher is present and working.
‡ Do not operate the machine near any flame.
IN OPERATOR’S CAB
‡ Do not leave tools or spare parts lying around in the operator’s compartment. They may damage
or break the control levers or switches. Always put them in the tool box on the right side of the
machine.
‡ Keep the cab floor, controls, steps and handrails free of oil, grease, snow, and excess dirt.
‡ Check the seat belt, buckle and hardware for damage or wear. Replace any worn or damaged
parts. Always use seat belts when operating your machine.
Seat belts ➞See “27. SEAT BELT”.
A0055020

1-8
7. PRECAUTIONS DURING OPERATION  WARNING: For reasons of safety, always follow these safety precautions.
A0055060
VENTILATION FOR ENCLOSED AREAS
‡ If it is necessary to start the engine within an enclosed area, provide adequate ventilation. Exhaust
fumes from the engine can KILL.
PRECAUTIONS FOR MIRRORS, WINDOWS AND LIGHTS
‡ Remove all dirt from the surface of the windows and lights to ensure that you can see well.
‡ Adjust the side mirror so that you can see clearly from the operator’s seat, and always keep the
surface of the mirror clean. If any glass is broken, replace it with a new part.
‡ Check that the head lamps and working lamps light up properly.
CHECK MACHINE
‡ Before starting the engine, adjust the operator’s seat so that you can carry work easily and in
comfort.
If the operator’s seat is not properly adjusted, it will cause mistaken operation and fatigue, with
the danger that this will cause an accident.
‡ Adjust the seat so that you can operate the control levers and pedals properly with your back
against the seat back.
Adjustment of operator’s seat ➞See “12.1.3 ADJUSTMENT BEFORE OPERATION”.
‡ Before starting the engine, check that the safety lock levers are at the LOCK position.
‡ Before starting the engine, always carry out the walk-around check, checks before starting, and
operations and checks before starting the engine.
Walk-around check ➞See “12.1.1 WALK-AROUND CHECK”.
Checks before starting ➞See “12.1.2 CHECK BEFORE STARTING”.
Operations and checks before starting engine ➞See “12.1.4 OPERATIONS AND CHECKS BE-
FORE STARING ENGINE.”.
Carry out the above checks and check that there is no abnormality. If there is damage which can not
be repaired, attach the warning tag to the work equipment control lever.

1-9
Before traveling or operating, check that the safety bar is se-
curely fixed in the free condition.
7. PRECAUTIONS DURING OPERATION
 WARNING: Failure to follow these safety precautions may lead
to a serious accident.
Before operating the machine or work equipment, do as follows.
‡ Sound the horn to warn people in the area.
‡ Check that there is no one near the machine. Be particularly
careful to check behind the machine.
‡ If necessary, designate a person to check the safety. This is
particularly necessary when traveling in reverse.
‡ When operating in areas that may be hazardous or have poor
visibility, designate a person to direct worksite traffic.
‡ Do not allow any one to enter the line of travel of the machine.
This rule must be strictly observed even on machines equipped
with a back-up alarm or rear view mirror.
CHECK SAFETY
7.2 OPERATING MACHINE
WHEN STARTING ENGINE
‡ Walk around your machine again just before mounting it, checking for people and objects that
might be in the way.
‡ NEVER start the engine if a warning tag has been attached to the control.
‡ When starting the engine, sound the horn as an alert.
‡ Start and operate the machine only while seated.
‡ Do not allow any person other than the operator in the operator’s compartment or any other place
on the machine.
‡ For machines equipped with a back-up alarm buzzer, check that the alarm buzzer works properly.
CHECK WHEN TRAVELING IN REVERSE

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7. PRECAUTIONS DURING OPERATION  WARNING: For reasons of safety, always follow these safety precautions.
PRECAUTIONS WHEN TRAVELING
‡ It is dangerous to look around you when carrying out operations. Always concentrate on your
work.
‡ Excessive speed, sudden starting, sudden stopping, sudden turns, and coasting when traveling
are dangerous. Always drive carefully.
‡ If you find any abnormality in the machine during operations (noise, vibration, smell, abnormali-
ties in gauges), move the machine immediately to a safe place, then park the machine and
investigate the cause.
‡ Travel on level roads with the bucket 25 – 45 cm (10 – 18 in) above the ground surface.
‡ When traveling on rough ground surfaces, travel at low speed, and avoid sudden turning when
changing direction.
‡ If the engine stops when the machine is traveling, the steering will not work. This is dangerous,
so apply the brakes immediately and stop the machine.
‡ To avoid hitting other machines, always keep a safe distance from other machines during
operations an when traveling.
TRAVELING ON SLOPES
‡ Traveling on hills, banks or slopes that are steep could result in the machine tipping over or
slipping.
‡ On hills, banks or slopes, carry the bucket closer to the ground, approximately 20 to 30 cm (8 to
12 in) above the ground. In case of emergency, quickly lower the bucket to the ground to help the
machine stop and prevent it from tipping over.
‡ Do not turn on slopes or travel across slopes. Always go down to a flat place to perform these
operations.
‡ Do not travel up and down on grass, fallen leaves, and wet steel plates. These materials may allow
the machine to slip, if it is traveling sideways. Keep travel speed very low.
‡ When traveling down a slope, use the braking force of the engine and travel slowly.
‡ If the engine stops on a slope, depress the brake immediately, lower the bucket, and apply the
parking brake to stop the machine.
‡ When carrying a load, travel forward when going uphill and in reverse when going downhill.
INCORRECT CORRECT
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DO NOT GO CLOSE TO HIGH-VOLTAGE CABLES
‡ Going close to high-voltage cables can cause electric shock. Always maintain the safe distance
given below between the machine and the electric cable.
‡ The following actions are effective in preventing accidents.
1) Wear shoes with rubber or leather soles.
2) Use a signalman to give warning if the machine approaches too close to the electric cable.
‡ If the work equipment should touch the electric cable, the operator should not leave the operator’s
compartment.
‡ When carrying out operations near high voltage cables, do not let anyone come close to the
machine.
‡ Check with the electricity company about the voltage of the cables before starting operations.
Min. safety
Voltage distance
6.6 kV 3 m 10ft
33.0 kV 4 m 14ft
66.0 kV 5 m 17ft
154.0 kV 8 m 27ft
275.0 kV 10 m 33ft
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7. PRECAUTIONS DURING OPERATION
 WARNING: Failure to follow these safety precautions may lead
to a serious accident.
PRECAUTIONS WHEN OPERATING
‡ Be careful not to approach too close to the edge of cliffs.
When making embankments or landfills, or when dropping soil over a cliff, dump one pile, then
use the next pile of soil to push the first pile.
‡ Be careful not to let the bucket hit the dump truck or the side of the excavated ditch.
‡ The load suddenly becomes lighter when the soil is pushed over a cliff or when the machine
reaches the top of a slope. When this happens, there is danger that the travel speed will suddenly
increase, so be sure to reduce the speed.
‡ Always carry out loading operations up-wind to protect yourself from dust.
‡ When the bucket is fully loaded, be particularly sure to avoid sudden starting, turning, or stopping.
‡ When loading a dump truck, check that there is no one in the area. Be careful also that the load
does not drop when it is being loaded.
ENSURE GOOD VISIBILITY
‡ When working in dark places, install working lamps and head lamps, and set up lighting in the
work area if necessary.
‡ Stop operations if the visibility is poor, such as in mist, snow, or rain, and wait for the weather
to improve to a condition that allows the operation to be carried out safely.