.

MAINTENENCE MAINTENENCE SCHEDURE CHART

MAINTENENCE SCHEDURE CHART

MAINTENENCE SCHEDURE CHART

INITIAL 250 HOURS SERVICE (ONLY AFTER THE FIRST 250 HOURS)
Change oil in engine oil pan, replace engine oil filter cartridge 4- 45
Replace transmission oil filter element 4- 48
Change oil in transmission case 4- 52
Replace transmission and rear brake cooling oil filter element 4- 53
Replace steering, hoist oil filter element 4- 57
Change oil in final drive case 4- 58
Change oil in differential case 4- 59
Change oil in steering, hoist oil tank 4- 61

INITIAL 2000 HOURS SERVICE (ONLY AFTER THE FIRST 2000 HOURS)
Check injector setting load, adjust 4- 17

WHEN REQUIRED
Clean inside of cooling system 4- 21
Check, clean or replace air cleaner 4- 18
Check level of window washer fluid, add fluid 4- 23
Clean air conditioner air filter 4- 23
Check refrigerant (gas) level 4- 24
Check dump body 4- 24
Check electric intake air heater 4- 24
Check length of suspension cylinder, check oil level 4- 25
Bleed air from rear brake 4- 26
Bleed air from front brake 4- 27
Bleed air from parking brake 4- 28
Clean, check radiator fins and after cooler fins 4- 29
Check play of output coupling of output shaft 4- 29
Selection and inspection of tires 4- 30

CHECK BEFORE STARTING

EVERY 250 HOURS SERVICE

Check oil level in differential case, add oil 4- 34
Check oil level in final drive case, add oil 4- 34
Lubrication 4- 35
Check drive shaft 4- 36
Check level of battery electrolyte 4- 37
Check alternator belt tension, adjust 4- 39
Check air conditioner compressor belt tension, adjust 4- 40
Clean breather 4- 41
Check frame 4- 42
Check braking capacity of foot brake 4- 42
Check braking capacity of retarder brake 4- 43
Check braking capacity of parking brake 4- 43
Check, clean automatic suspension 4- 44

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MAINTENENCE SCHEDURE CHART MAINTENENCE

EVERY 500 HOURS SERVICE

Change oil in engine oil pan, replace engine oil filter cartridge 4- 45
Replace fuel filter cartridge 4- 46
Clean fuel tank strainer 4- 47
Replace transmission oil filter element 4- 48
Check wear of front disk brake pad 4- 49
Check wear of fan belt 4- 50

EVERY 1000 HOURS SERVICE

Replace corrosion resistor cartridge 4- 51
Replace oil in transmission case and clean strainer 4- 52
Replace transmission and rear brake cooling oil filter element 4- 53
Replace brake oil filter element 4- 54
Lubrication 4- 55
Check wear of rear brake disk 4- 56
Check tightening parts for turbocharger 4- 56
Check play of turbocharger rotor 4- 56

EVERY 2000 HOURS SERVICE

Replace steering, hoist oil filter element 4- 57
Clean hydraulic tank strainer 4- 58
Change oil in final drive case 4- 58
Change oil in differential case 4- 59
Clean differntial case breather 4- 59
Clean engine breather element 4- 60
Check alternator starter 4- 60
Check, adjust engine valve clearance 4- 60
Check, clean turbocharger 4- 60
Check accumulator gas pressure 4- 60

EVERY 4000 HOURS SERVICE

Change oil in steering, hoist oil tank 4- 61
Check water pump 4- 61
Check fan pulley and tension pulley 4- 61
Check vibration damper 4- 61

EVERY 6000 HOURS SERVICE

Lubricate drive shaft 4- 62

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MAINTENENCE SERVICE PROCEDURE

SERVICE PROCEDURE
INITIAL 250 HOURS SERVICE (ONLY AFTER THE FIRST 250 HOURS)
Carry out the following maintenance only after the first 250 hours.
Change oil in engine oil pan, replace engine oil filter cartridge
Replace transmission oil filter element
Change oil in transmission case
Replace transmission and rear brake cooling oil filter element
Replace steering, hoist oil tank filter element
Clean hydraulic tank strainer
Change oil in final drive case
Change oil in differential case
Change oil in steering, hoist oil tank
For details of the method of replacing or maintaining, see EVERY 500 HOURS, EVERY 1000 HOURS, EVERY
2000 HOURS SERVICE and EVERY 4000 HOURS SERVICE.

INITIAL 2000 HOURS SERVICE (ONLY AFTER THE FIRST 2000 HOURS)
Perform the following maintenance after 2000 hours of traveling only for the first meintenance of the new car.

CHECK INJECTOR SETTING LOAD, ADJUST

The special tools are needed for the check and adustment.
Ask your Komatsu distributor for checking and adjustment.

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SERVICE PROCEDURE MAINTENENCE

WHEN REQUIRED

CHECK, CLEAN OR REPLACE AIR CLEANER

If inspection, cleaning, or maintenance is carried out with the engine running, dirt will get into the engine and the engine will
suffer damage. Always stop the engine before carrying out these operations.
When using compressed air, there is danger that dirt may be blown around and cause serious injury.
Always use safety glasses, dust mask, and other protective equipment.

CHECKING
1. Check that the yellow display in the transparent portion of dust
indicator (1) does not indicate 7.5 kPa (0.076 kgf/cm2, 1.1 PSI).
2. If the red line indicates 7.5 kPa (0.076 kgf/cm2, 1.1 PSI), clean
or replace the air cleaner element immediately.
3. After checking, cleaning, or replacing, press the top of dust
indicator (1) to return the yellow display to its original position.

NOTICE
Do not clean the element until the dust indicator shows 7.5 kPa (0.076
kgf/cm2, 1.1 PSI).
If the element is cleaned frequently before the dust indicator shows 7.5
kPa (0.076 kgf/cm2, 1.1 PSI), the air cleaner will not be able to display its
basic 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 the pressure rises to 5.0 kPa (0.051 kgf/cm2, 0.7 PSI) immediately after
it is cleaned, replace the air cleaner elements (outer element and inner
element). Even if the rise in pressure is slow, replace the air cleaner
element once a year.

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MAINTENENCE SERVICE PROCEDURE

CLEANING OR REPLACING OUTER ELEMENT

1. Release lock (2) of cover (3), then remove the cover.
2. Remove outer element (5).
3. Clean the air cleaner body interior and the cover.
4. Direct dry compressed air (less than 0.69 MPa (7 kgf/ cm2, 99.4
PSI)) to the element from inside along its folds, then direct it
from outside along its folds and again from inside.
1) Remove one seal every time the element is clean.
2) Replace the outer element if it has been cleaned 6 times
repeatedly or used throughout a year. Replace the inner
element at the same time.
3) If the dust indicator shows 5.0 kPa (0.051 kgf/cm2, 0.7 PSI)
immediately after cleaning, even if the outer element has
not been cleaned six times, replace both the inner and
outer elements.
4) Remove evacuator valve (4) and clean it with compressed
air. After cleaning, install it again.

NOTICE
After cleaning, put a light bulb inside the element, and if small holes or
thinner parts are found, replace the element.
When cleaning the element, do not hit it or beat it against anything.
Do not use any element if the element folds or gasket or seal are damaged.

5. Install the cleaned element, then install cover (3).

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SERVICE PROCEDURE MAINTENENCE

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 installed in Step 2.
4. Install a new inner element to the body.
Do not clean and re-use an inner element.
5. Install the outer element and the cover.
6. Remove evacuator valve (4) and clean it with compressed air. After cleaning, install it again.
7. After replacing the element, return the yellow display on the dust indicator to its original position.

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MAINTENENCE SERVICE PROCEDURE

CLEAN INSIDE OF COOLING SYSTEM

Immediately after the engine is stopped, the engine coolant is hot and the pressure inside the radiator is high. Removing the
cap and draining the water under this condition could cause burns. Allow the engine to cool down, then turn the cap slowly
to release the pressure.
Start the engine and flush the system. When standing up or leaving the operator's seat, set the shift lever to the N position and
set the parking brake switch to the PARKING position.
For details of starting the engine, see "OPERATIONS, CHECKS BEFORE STARTING (PAGE 3-79)" and "STARTING ENGINE
(PAGE 3-81)" in the OPERATION section of the Operation and Maintenance Manual.
When the undercover is removed, there is danger of touching the fan.
Never go to the front of the machine when the engine is running.

Stop the machine on level ground when cleaning or changing the coolant.

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, autume)
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 no using antifreeze every 1000 hours,
whichever come first

Use a permanent type of antifreeze.

If, for some reason, it is impossible to use permanent type antifreeze, use an antifreeze containing ethylene glycol.
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 (50°F) lower when deciding the mixing rate.

Mixing rate of water and antifreeze

Min. atmospheric °C -10 -15 -20 -25 -30

temperature °F 14 5 -4 -13 -22
Liters 46 56 63 71 77
Amount of antifreeze
US gal 12.2 14.8 16.6 18.8 20.35
Liters 108 98 91 83 77
Amount of water
US gal 28.5 25.9 24.1 21.9 20.35

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SERVICE PROCEDURE MAINTENENCE

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.

Komatsu genuine "Super Coolant" (AF-ACL(red)) is recommended for anti-freeze.

Use city water for the cooling water.

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.

1. Stop the engine, then tighten 2 valves (1) of the corrosion

resistor.

2. Turn radiator cap (2) slowly to remove it.

3. Open drain valve (3) at the bottom of the radiator and drain
valve (4) at the side face of the cylinder brock and drain the
water.
4. After draining the water, close drain valves (3) and drain plug
(4), and fill with tap water.
5. When the radiator is full, start the engine, and run it at low
idling.
Keep the engine running at low idling for 10 minutes until the
water temperature reaches more than 90°C (194°F).
6. Stop the engine, open drain valves (3) and drain plug (4), and
drain the water. After draining the water, close them.
7. After draining the water, clean the cooling system with cleaning
agent.
For the cleaning method, see the instructions for the cleaning
agent.
8. After flushing, open drain valves (3) and drain plug (4), and
drain all the water.
9. Close drain valves (3) and drain plug (4).

10. Replace the corrosion resistor, then open a valve (1) of the corrosion resistor at two points.
For replacing corrosion resistor, see "REPLACE CORROSION RESISTOR CARTRIDGE (PAGE 4-51)".
11. Decide the proportions of antifreeze and water according to the table for the mixing rate of water and antifreeze.
12. To remove the air contained in the coolant, run the engine at low idle for 5 minutes, then run for a another 5
minutes at high idle. (When doing this, leave the water filler cap OFF.)
13. Stop the engine. About 3 minutes later, supply city water up to the water filler, then close radiator cap.

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MAINTENENCE SERVICE PROCEDURE

14. Drain the cooling water from inside subtank (5), flush the inside
of the subtank, then fill with water to a point between the H and
L marks.

CHECK LEVEL OF WINDOW WASHER FLUID, ADD FLUID

Carry out this check 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, fill with automobile window washer fluid.
Be careful not to let dirt or dust get in when adding fluid.

When operating at below freezing point, use fluid with antifreeze.

CLEAN AIR CONDITIONER AIR FILTER

If the air filter at the suction port of the air conditioner unit or the air filter at the fresh air intake port become clogged,
the cooling or heating capacity will drop, so clean the filters once a week.

1. Open cover (1) at the side of the cab.

2. Pull out the air filter (FRESH filter) and clean it with
compressed air.

3. Open cover (2) at the left side at the rear of the operator's seat.
4. Pull out the air filter (recirculated air filter) in the air conditioner
unit suction port at the end of the duct, and blow off the dust
with a weak flow of compressed air or with a soft brush.

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SERVICE PROCEDURE MAINTENENCE

CHECK REFRIGERANT (GAS) LEVEL

If the refrigerant used in the cooler 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 cooling effect is poor, the level of the refrigerant (gas) is

probably low.
Check the sight glass of the receiver dryer on the inside left of the
radiator guard.

REMARK
Run the engine at idling, and if bubbles appear in the sight glass
when the air conditioner is set to cooling, the refrigerant level is low,
so please contact your Komatsu distributor to have it refilled.

CHECK DUMP BODY

Check that there are no cracks in the dump body.

1. Clean the dump body to make it easier to check.

2. Check all parts of the dump body for damage.
If any cracks or abnormal wear are found, carry out repairs.
Contact your Komatsu distributor for details of the repair procedure.

CHECK ELECTRIC 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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MAINTENENCE SERVICE PROCEDURE

CHECK LENGTH OF SUSPENSION CYLINDER, CHECK OIL LEVEL

When traveling, if the unevenness of the road surface is transmitted directly to the chassis (the machine bounces
or the cylinders retract and hit the stopper), carry out the following checks.

CHECK LENGTH OF CYLINDER

Front
Check that the bottom of the suspension cylinder cover is within
range (A) shown by the arrow on the label when the machine is
unloaded and on flat ground.

At the same time, remove cover (1) and measure the distance from
the shoulder at the head of the suspension cylinder rod to the top
face of the flange with the machine unloaded.
(B):239 to 259 mm (9.4 to 10.2 in)
(C):506 to 526 mm (19.9 to 20.7 in)
After checking, contact your Komatsu distributor for repairs if any
abnormality is found.

Rear
Measure the distance from the shoulder at the head of the
suspension cylinder rod to the top face of the flange.
(D):210 to 230 mm (8.3 to 9.1 in)
After checking, contact your Komatsu distributor for repairs if any
abnormality is found.

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SERVICE PROCEDURE MAINTENENCE

BLEED AIR FROM REAR BRAKE

Stop the machine on level ground and put blocks under the wheels before bleeding the air.

To make it easier to bleed the air, warm the oil up to a temperature of at least 40°C (104°F) before bleeding the air.
Bleed the air from the rear brakes in the same way on both the left and right sides.

1. Start the engine, check that the oil in the transmission case is the specified level, and check if the brake oil
pressure caution lamp is out.
2. Remove the cap installed to bleeder screw (1) of the slack
adjuster, then insert a vinyl hose.
Prepare a container with oil in it and insert the other end of the
hose approx. 50 mm (2.0 in) below the surface of the oil.
(Use any commercially available vinyl hose.)
3. Depress the brake pedal and loosen bleeder screw (1) approx.
3/4 turns. Keep the pedal depressed until no more bubbles
come out from the vinyl hose.
4. Pull the retarder control lever and loosen bleeder screw (1)
approx. 3/4 turns. Keep the retarder control lever depressed
until no more bubbles come out from the vinyl hose.
5. After bleeding the air, tighten bleeder screw (1) securely and fit the cap.
6. The procedure for bleeder screw (2) of the rear brake is the
same as for the slack adjuster (with Step 4 excluded).
7. Add engine oil. For details, see "CHECK OIL LEVEL IN
TRANSMISSION CASE, ADD OIL (PAGE 3-72)".

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MAINTENENCE SERVICE PROCEDURE

BLEED AIR FROM FRONT BRAKE

Stop the machine on level ground and put blocks under the wheels before bleeding the air.

To make it easier to bleed the air, warm the oil up to a temperature of at least 40°C (104°F) before bleeding the air.
Repeat the same procedure on the left and right sides.
When bleeding the air from the front brakes and rear brakes at the same time, bleed the air from the rear brakes first.

1. Start the engine, check that the oil in the transmission case is at the specified level, that the brake oil pressure
caution lamp is out, and that the front brake OFF switch is at the OFF position.
2. Remove the cap of bleeder screw (1), then insert a vinyl hose
(inside diameter: 8 mm (0.315 in)). Prepare a container with oil
in it and insert the other end of the hose approx. 50 mm (2.0 in)
into the oil. (Use any commercially available vinyl hose.)
3. Depress the brake pedal and loosen bleeder screw (1) approx.
3/4 turns. Keep the pedal depressed until no more bubbles
come out from the vinyl hose.
4. After bleeding the air, tighten bleeder screw (1) securely and fit
the cap.

5. Add engine oil. For details, see "CHECK OIL LEVEL IN TRANSMISSION CASE, ADD OIL (PAGE 3-72)".

4 - 27
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SERVICE PROCEDURE MAINTENENCE

BLEED AIR FROM PARKING BRAKE

Stop the machine on level ground and put blocks under the wheels before bleeding the air.

To make it easier to bleed the air, warm the oil up to a temperature of at least 40°C (104°F) before bleeding the air.
Bleed the air from the parking brakes in the same way on both the left and right sides.

1. Start the engine, check that the oil in the transmission case is the specified level, and check if the brake oil
pressure caution lamp is out.
2. Remove the cap of bleeder screw (1), install to the block at the
top of the slack adjuster, then insert a vinyl hose.
Prepare a container with oil in it and insert the other end of the
hose approx. 50 mm (2.0 in) into the oil. (Use any
commercially available vinyl hose.)
3. Pull the retarder control lever, set the parking brake switch to
PARKING, then loosen bleeder screw (1) approx. 3/4 turns.
Continue until no more bubbles come out from the vinyl hose.
4. After bleeding the air, tighten bleeder screw (1) securely and fit
the cap.
5. The procedure for parking brake bleeder screw (2) is the same
as for the block on top of the slack adjuster.
6. Add engine oil. For details, see "CHECK OIL LEVEL IN
TRANSMISSION CASE, ADD OIL (PAGE 3-72)".

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MAINTENENCE SERVICE PROCEDURE

CLEAN, CHECK RADIATOR FINS AND AFTER COOLER FINS

If compressed air scattered around dust and debris, there is danger of injury. Always wear protective equipment such as
protective glasses and mask.

If radiator fins (1) or aftercooler fins (2) become clogged or bent, it

will cause overheating of the engine, so always clean or carry out
inspection, and ask your Komatsu distributor to take the necessary
action.
Cleaning can be carried out by using jets of air, steam, or water,
but be careful not to let the nozzle contact the fin.
Air pressure : Max. 0.98 MPa (10 kgf/cm2, 142 PSI)
Steam pressure : Max. 0.39 MPa (4 kgf/cm2, 56.8 PSI)
When using compressed air or steam, keep the nozzle at a right
angle to the radiator and after cooler.
Examine the rubber hose, and if any cracks or brittle places are
found, replace the hose. In addition, check also for loose hose
clamps.

CHECK PLAY OF OUTPUT COUPLING OF OUTPUT SHAFT

If any abnormal noise occurs around the output shaft or front drive
shaft, the rubber inside the output shaft may be deteriorated or
damaged, so check the play of the coupling as follows.

Play in circumferential direction

Using a bar, move the coupling in the direction of the
circumference and check the play (a) in the circumferential
direction at the outside diameter of the coupling.
Standard: Max. 15 mm (0.6 in)

REMARK
If the play range is exceeded, the engine fan will start to rotate, so
when inspecting the play, check first that the engine fan is not
rotating.

If the result of the measurement shows that it is greater than the

standard value, please contact your Komatsu distributor for
disassembly and inspection.

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SERVICE PROCEDURE MAINTENENCE

SELECTION AND INSPECTION OF TIRES

If a tire or a rim is handled wrongly, the tire may burst or may be damaged
and the rim may be broken and scattered, and that can cause serious injury
or death.
Since maintenance, disassembly, repair and assembly of the tires and
rims require special equipment and skill, be sure to ask a tire repair
shop to carry out the work.
Do not heat or weld the rim to which the tire is installed. Do not make a
fire near the tire.

SELECTION OF TIRES

Select the tires according to the conditions of use and the weight of the attachments on the machine. Use only specified tires and
inflate them to the specified pressure.

Select the tires according to the conditions of use and the weight of the attachments of the machine. Use the
following table.
Since the travel speed indicated on the speedometer varies with the tire size, consult your Komatsu distributor when
using optional tires.

Max. load [kg (lb)] Size Operating model Remarks

15500 (34178) 24.00-35-36PR HD465: standard
HD465: if equipped
Front wheel 18500 (40793) 24.00R35«« HD605: standard
18500 (40793) 24.00-35-48PR HD605: if equipped Type 1 for
construction
15500 (34178) 24.00-35-36PR HD465: standard equipment
HD465: if equipped
Rear wheel 18500 (40793) 24.00R35«« HD605: standard
18500 (40793) 24.00-35-48PR HD605: if equipped

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MAINTENENCE SERVICE PROCEDURE

CHECK OF INFLATION PRESSURE OF TIRES AND INFLATION OF THEM

When inflating a tire, check that any person will not enter the working
area and use an air chuck which has a clip and which can be fixed to the
air valve.
While inflating the tire, check the inflation pressure occasionally so that
it will not rise too high.
If the rim is not fitted normally, it may be broken and scattered while the
tire is inflated. Accordingly, place a guard around the tire and do not
work in front of the rim but work on the tread side of the tire.
Abnormal drop of inflation pressure and abnormal fitting of the rim
indicate a trouble in the tire or rim. In this case, be sure to ask a tire
repair shop for repair.
Be sure to observe the specified inflation pressure.
Do not adjust the inflation pressure of the tires just after high-speed
travel or heavy-load work.

Check
Measure the inflation pressure with a tire pressure gauge while the tires are cool before starting work.

Inflation of tires
Adjust the inflation pressure properly.
When inflating a tire, use an air chuck which can be fixed to the air valve of the tire as shown in the figure. Do not
work in front of the rim but work on the tread side of the tire.
The proper inflation pressure is shown below.

HD465-7

Tire size Inflation pressure

24.00-35-36PR (standard) 0.47 MPa (4.75 kgf/cm2, 67.4 PSI)
24.00R35«« (if equipped) 0.69 MPa (7.00 kgf/cm2, 99.4 PSI)

HD605-7

Tire size Inflation pressure

24.00R35«« (standard) 0.69 MPa (7.00 kgf/cm2, 99.4 PSI)
24.00-35-48PR (if equipped) 0.64 MPa (6.50 kgf/cm2, 92.3 PSI)

NOTICE
If the tires are used when the inflation pressure is less than the value given in the table above, the rim may be damaged.
Always keep the tire inflation pressure within +0 to +0.03 MPa (0.3kgf/cm2, 4.3PSI) of the value in the table above.

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SERVICE PROCEDURE MAINTENENCE

PRECAUTIONS WHEN REPLACING TIRE

If the hub nuts (1) have been tightened again after replacing the
tire, travel for 5 to 6 km, then tighten again to settle all the
contacting parts.
In particular, there are more contacting parts on the rear wheels
than on the front wheels, so it will take time for the parts to settle.
For this reason, repeat the tightening process for the first 50 hours
after installation.

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MAINTENENCE SERVICE PROCEDURE

CHECK BEFORE STRATING

For the following items, see "CHECK BEFORE STARTING (PAGE 3-70)".
Check coolant level, add water
Check dust indicator
Check oil level in engine oil pan, add oil
Check oil level in transmission case, add oil
Check oil level in steering and hoist oil tank, add oil
Drain water and sediment in fuel tank
Check fuel level, add fuel
Check wheel hub nuts, tighten
Check central warning lamp, alarm buzzer, monitor lamps and meters
Check braking effect
Check braking capacity of emergency brake
Check manual emergency steering
Check auto-emergency steering
Check backup alarm
Check electrical wiring
Check inflation pressure of tires

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SERVICE PROCEDURE MAINTENENCE

EVERY 250 HOURS SERVICE

CHECK OIL LEVEL IN DIFFERENTIAL CASE, ADD OIL

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.
If there is still pressure remaining inside the case, the oil or plug may fly out. Turn the plug slowly to release the pressure, then
remove it carefully.

1. Remove plug (G) and check that the oil level is near the bottom
of the plug hole.
2. If the oil level is too low, add engine oil through the plug hole
until the oil overflows.

CHECK OIL LEVEL IN FINAL DRIVE CASE, ADD OIL

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.
If there is still pressure remaining inside the case, the oil or plug may fly out. Turn the plug slowly to release the pressure, then
remove it carefully.

1. Stop the machine so that the TOP casting mark is at the top
and drain plug (P) is at the bottom.
2. Remove plug (G) and check that the oil level is near the bottom
of the plug hole.
3. If the oil level is too low, add engine oil through the plug hole
until the oil overflows.

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MAINTENENCE SERVICE PROCEDURE

LUBRICATION
1. Stop the engine.
2. Using a grease pump, pump in grease through the grease fittings marked by the arrows.
3. After greasing, wipe off any old grease that was pushed out.

Carry out the greasing operation every day when operating in

places where the grease flows out easily after traveling through
mud or water.

(1) Dump body hinge pin (left and right: 1 point each)

(2) Rear suspension (left and right: 2 points each)

(3) Differential support (left and right: 4 points each)

(4) Hoist cylinder pin (left and right: 2 points each)

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SERVICE PROCEDURE MAINTENENCE

(5) Front suspension (left and right: 1 point each)

(6) Steering cylinder pin (4 points)

(7) Steering link pin (5 points)

(8) Steering linkage (left and right: 3 points each)

CHECK DRIVE SHAFT

If there is any abnormality, such as looseness of the drive shaft
connection, play in the spline or bearing portion, or runout of the
shaft, please contact your Komatsu distributor for repair.

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MAINTENENCE SERVICE PROCEDURE

CHECK LEVEL OF BATTERY ELECTROLYTE

Carry out this check before operating the machine.

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 also cause an explosion.
The battery generates flammable gas and there is danger of explosion, 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 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.

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 pipette 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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SERVICE PROCEDURE MAINTENENCE

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 pipette 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 equipped)
If it is possible to use and indicator to check the electrolyte level, follow the instructions given.

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.

MAINTENENCE SERVICE PROCEDURE

CHECK ALTERNATOR BELT TENSION, ADJUST

CHECKING
The belt should normally deflect by above 15 mm (0.6 in) (a) when
pressed with the thumb (with a force of approx. 58.8 N (6 kgf) at a
point midway between the drive pulley and alternator pulley.

ADJUSTING
1. Loosen bolts and nuts (1) to (4), then turn nut (5) to adjust the
tension of the belt.
Tighten nut (5) as follows:
TIGHTEN to INCREASE belt tension
LOOSEN to DECREASE belt tension
2. After adjusting the belt, tighten bolts and nuts (1) to (4) in
number order to secure the alternator in position.
3. Tighten nut (5).

REMARK
Check each pulley for breakage and wear of the V-groove. In
particular, check that the V-belt does not touch the bottom of the
V-groove.
If any abnormality is found, ask your Komatsu distributor for
replacement of the pulley.
If the V-belt is so lengthened that it cannot be adjusted any more
or if it has any cuts or cracks, replace it.
If the V-belt has been replaced with a new part, there will be
initial elongation, so inspect and adjust it again after one-hour of
operation.

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SERVICE PROCEDURE MAINTENENCE

CHECK AIR CONDITIONER COMPRESSOR BELT TENSION, ADJUST

CHECKING
The belt should normally deflect by 10 mm (0.4 in) (a) when
pressed with the thumb (with a force of approx. 58.8 N (6 kgf)) at
a point midway between the air compressor pulley and drive pulley.

ADJUSTING
1. Loosen bolt (1).
2. Turn nut (2) to adjust so that the belt deflects by approx. 10 mm
(0.4 in) when pressed with a finger force of approx. 58.8 N (6
kgf) at a point midway between the air conditioner compressor
pulley and drive pulley.
3. Tighten bolt (1) and nut (2) to secure the compressor in
position.
4. Check each pulley for damage, wear of the V-groove, and wear
of the V-belt. In particular, be sure to check that the V-belt is not
touching the bottom of the V-groove.
5. If the V-belt is so lengthened that it cannot be adjusted any
more or if it has any cuts or cracks, replace it.
6. If the V-belt has been replaced with a new part, there will be initial elongation, so adjust the belt again after
operating for 2 to 3 days.

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.

MAINTENENCE SERVICE PROCEDURE

CLEAN BREATHERS
Remove the mud and dirt from around the breathers, then remove the breathers and wash out the dirt with clean
diesel oil or flushing oil.

Transmission case breather (2 points)

Steering, hoist oil tank

1. Remove nut (1), then remove cover (2) and wash element (3).
2. Install element (3), then install cover (2) and nut (1).

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.

SERVICE PROCEDURE MAINTENENCE

CHECK FRAME

When carrying out inspection of the machine with the dump body raised, always set the dump lever to the HOLD position, lock
with the safety lock knob, then use the safety pin.

1. Wash the frame to make it easier to check.

2. Check all parts of the frame for damage.
In particular, check the colored portions in the diagram and if
any cracks or damage are found, repair the damage. Please
contact your Komatsu distributor for details of the repair
procedure.

CHECK BRAKING CAPACITY OF FOOT BRAKE

If the machine moves, it will lead to serious injury. If machine begins to move during the inspection of braking capacity, lower the
engine speed immediately, set shift lever at N position, and then set parking brake switch at PARKING position.

Check the braking capacity of the foot brake as follows.

1. Stop the machine on flat ground and depress service brake (1).
2. Set shift lever (2) to the D position, gradually raise the engine
speed, and check that the machine does not move even when
the engine speed reaches 1870 rpm. If the machine does not
move, it is normal.
3. Lower the engine speed, set shift lever at N position, and then
set parking brake valve lever at PARKING position. If any
abonormality is found, ask your Komatsu distributor for repair.

NOTICE
There is danger of damage inside the transmission, so always do this with
the shift lever at the "D" position. Do not use any other position.

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MAINTENENCE SERVICE PROCEDURE

CHECK BRAKING CAPACITY OF RETARDER BRAKE

If the machine moves, it will lead to serious injury or death. If machine begins to move during the inspection of braking capacity,
lower the engine speed immediately, set shift lever at N position, and then depress the foot brake.

Check the braking capacity of the retarder brake as follows.

1. Stop the machine on flat ground and pull retarder control lever
(1) fully.
2. Set shift lever (2) to the D position, gradually raise the engine
speed, and check that the machine does not move even when
the engine speed reaches 1400 rpm. If the machine does not
move, it is normal.
3. Lower the engine speed, set shift lever at N position. If any
abnormality is found, ask your Komatsu distributor for repair.

NOTICE
There is danger of damage inside the transmission, so always do this with
the shift lever at the "D" position. Do not use any other position.

CHECK BRAKING CAPACITY OF PARKING BRAKE

If the machine moves, it will lead to serious injury or death. If machine begins to move during the inspection of braking capacity,
lower the engine speed immediately, set shift lever at N position, and then depress the foot brake.

Check the braking capacity of the parking brake as follows.

1. Stop the machine on flat ground and set parking brake switch
(1) to PARKING.
2. Set shift lever (2) to the D position, gradually raise the engine
speed, and check that the machine does not move even when
the engine speed reaches 1670 rpm. If the machine does not
move, it is normal.
3. Lower the engine speed, set shift lever at N position. If any
abnormality is found, ask your Komatsu distributor for repair.

NOTICE
There is danger of damage inside the transmission, so always do this with
the shift lever at the "D" position. Do not use any other position.

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SERVICE PROCEDURE MAINTENENCE

CHECK, CLEAN AUTOMATIC SUSPENSION

(If equipped)

Follow the precautions below strictly.

One should sit on the operator's seat, preparing to stop the engine at
any moment, and contact with the other.
Set the parking brake switch at PARKING position to prevent the
machine from moving.
When working near fan or belts, do not bring your body or any materials
closer that can be dragged into.
Do not touch the gearshift lever. When you operate the dump lever,
always give a signal to your fellow workers to tell them to move to a safe
area.
If the materials or tools are dropped onto fan or belts, they fly away or
cut. Never drop or insert materials or tools.

1. When bolts of inspection cover (1) are loosened and the cover
is moved to the side, the inspection hole can be seen.

2. Check the positions of the link. Check that it moves to the

following positions:
For normal travel when empty: soft (a)
When the brake is depressed: medium (b)
When the dump lever is at any position other than FLOAT: hard
(c)

If any abnormality is found, please contact your Komatsu distributor for inspection and adjustment.

If operations are carried out on muddy or wet ground, mud will stick to the link, and the movement may become slow,
so check and clean.

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.

MAINTENENCE SERVICE PROCEDURE

EVERY 500 HOURS SERVICE

Maintenance for every 250 hours service should be carried out at the same time.

CHANGE OIL IN ENGINE OIL PAN, REPLACE ENGINE OIL FILTER CARTRIDGE

The parts and oil is at high temperature after the engine has been operated, and it can result in a burn. Wait for the oil to cool down
before changing it.

Refill capacity: 57 liters (15.6 US gal)

Filter wrench

1. Remove drain plug (1), then install the standard drain hose.
2. Set a container in position to catch the oil, then loosen drain the
valve (2) slowly to avoid getting oil on yourself, and drain the
oil. Be careful not to loosen drain valve (2) too much. This will
deform the stopper pin inside the valve.
3. Check the drained oil, and if there are excessive metal
particles or foreign material, please contact your Komatsu
distributor.
4. Remove the drain hose, then tighten drain valve (2) and drain
plug (1).
Tightening torque
Drain plug (1), drain valve (2): 68.6 ± 9.8N·m
(7 ± 1kgf·m, 50.6 ± 7.2 lbft)
Using the filter wrench, turn 2 full-flow filter cartridges (3) to the
left to remove them.
When doing this, to prevent getting oil on yourself, do not carry
out this operation from immediately under the cartridge.
In particular, if this operation is carried out immediately after
stopping the engine, a large amount of oil will come out, so wait
for 10 minutes before starting the operation.
5. Clean the filter holder, fill the new filter cartridge with engine oil,
coat the packing face and thread with engine oil (or coat thinly
with grease), then install the filter cartridge.
6. When installing the filter cartridge, tighten until the packing face is in contact with the filter holder, then tighten
a further 3/4 - 1 turn.
7. Add engine oil through oil filler (F) to fill to the specified level.
8. Run the engine for a short time at idling, then check the oil if it is filled up to a specified level. For details, see
"CHECK OIL LEVEL IN ENGINE OIL PAN, ADD OIL (PAGE 3-71)".

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.

SERVICE PROCEDURE MAINTENENCE

REPLACE FUEL FILTER CARTRIDGE

Immediately after the engine is stopped, all parts are at high temperature, so do not replace the filter immediately.
Wait for the engine to cool down before starting the operation.
Do not bring any fire or spark close.

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.
Always use a Komatsu genuine part for the fuel filter cartridge. If filters other than genuine filters are used, problems may occur
in the injection system, so never use substitute parts.

Filter wrench

1. Close supply valve (1) of the fuel tank.

2. Set the container to catch the fuel under the filter cartridge.
3. Using a filter wrench, turn filter cartridge (2) counterclockwise
to remove it.
4. Clean the filter head, fill the new filter cartridge with clean fuel,
coat the packing surface thinly with engine oil, and install it to
the filter holder.
Always use clean fuel when filling with fuel, and be careful not
to let any dirt or dust get in.
Add fuel from small hole (A) (dirty side) at eight places. Do not
add fuel from hole (B) (clean side) at the center.
5. When installing the filter cartridge, tighten it manually until its
packing face comes to contact the seal face of the filter holder,
then tighten it by further 3/4 of a turn.
If the filter cartridge is tightened excessively, the packing will
be damaged, causing fuel to leak. If it is tightened loosely, on
the other hand, fuel will seep out through the packing. Hence
be sure to strictly follow the specified tightening angle.

6. Open supply valve (1).

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.

MAINTENENCE SERVICE PROCEDURE

7. After replacing the filter cartridge, push air bleed valve (3) while
cranking the engine with the starting motor to bleed the air from
the circuit. When the engine is started, the air is bled from the
fuel system, so the cranking may continue for longer than
normal. In addition, even after the engine starts, there is still air
remaining in the fuel system, so the engine rotation may not
become stable for a short time, but this does not indicate any
abnormality. Continue to run at low idling until the engine
speed becomes stable.

8. If the engine does not start when the above operation is carried out, do as follows to fill the fuel pump with fuel.
1) Remove air bleed valve (3).
2) Add oil until clean fuel overflows from the valve hole.
3) Install air bleed valve (3).
Tightening torque: 12.7 N·m (1.3 kgf·m, 9.4 lbft)
4) Crank the engine with the starting motor.
9. 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 2 and 3 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 4 - 7 to install the filter cartridge.

REMARK
The air remaining in the fuel system will be exhausted while the engine is running.

CLEAN FUEL TANK STRAINER

1. Close supply valve (1) of the fuel tank.

2. Remove filter case (2).

3. Take out the strainer, clean off dirt clung to it, and wash it in
clean light oil or diesel oil.
If the strainer is damaged, replace it with a new one.
4. Install the strainer and filter case (2).
5. Open supply valve (1).
6. Bleed the air from the fuel circuit. For details, see Section
"REPLACE FUEL FILTER CARTRIDGE (PAGE 4-46)".

4 - 47
.

SERVICE PROCEDURE MAINTENENCE

REPLACE TRANSMISSION OIL FILTER ELEMENT

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.
When removing the oil filler cap, turn it slowly to release the internal pressure, then remove it.

1. Set the container to catch the oil under the filter case.
2. Remove drain plug (1) at the bottom of the filter case, drain the
oil, then tighten the plug again.
3. Loosen hexagonal portion (3) of case (2), then remove case
(2).
4. Remove the element and clean the inside of the case.
5. Replace the filter gasket and O-ring with new parts. Coat the
gasket and O-ring thinly with clean engine oil before installing.
6. Assemble the new element, then set the case in position and
install it.

Tightening torque for drain: 49 to 58.8 N·m

(5 to 6 kgf·m, 36.2 to 43.4 lbft)
Tightening torque for case: 58.8 to 78.5 N·m
(6 to 8 kgf·m, 43.4 to 57.9 lbft)

7. Run the engine for a short time at idling, then stop the engine, and check that the oil is up to the specified level.
For details, see "CHECK OIL LEVEL IN TRANSMISSION CASE, ADD OIL (PAGE 3-72)".

Run the engine at high idling, and when the oil is warmed up, if the Maintenance caution lamp flashes, replace
the element immediately.

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.

MAINTENENCE SERVICE PROCEDURE

CHECK WEAR OF FRONT DISC BRAKE PADS

If the pad is cotinued to use after the period of wear limit, not only the disk will be damaged but also the brake will loose its
effect, and it is dangerous. If the period of wear limit approaches, check frequently the condition to change the pad at proper
time.
Perform inspection every 250 hours if the work site is covered by lots of earth and sand and if it is at the location where the foot
brake is frequently used.

1. Insert the inspection gauge into the wear inspection hole (1)
and check.

2. The wear limit where stepped portion (3) of gauge (2) contacts
caliper (4) is 3 mm (0.1 in) (remaining thickness of pad), so
replace pad (5).
(A): Near wear limit
(B): Wear limit reached, so replace pad

After the inspection, if it is necessary to change the pad, contact your Komatsu distributor.

Left and right wheels are not always the same in terms of the amount of wear of the pad. So, perform the inspection
for both left and right. If either side shows the wear limit, be sure to change all 8 pads.

If the work is performed on the muddy and watery ground, the mud sticks to caliper or disc. Leaving the mud will
increase the wear of pad, so wash out throughly with water.

4 - 49
.

SERVICE PROCEDURE MAINTENENCE

CHECK FAN BELT FOR WEAR AND REPLACE

Inspect the V-belt and if it is in the following condition, replace the V-belt.
The V-belt is in contact with the bottom of the groove of each pulley
The V-belt is worn and has sunk below the outside diameter of the pulley
The V-belt is cracked or peeling

REPLACING
When replacing the V-belt, do as follows.
1. Replace the fan guard, then insert a bar of a length of approx.
50 cm (20 in) into the hole (Ø 18 mm (0.7 in)) in the tension
pulley bracket, and pull forward strongly.
2. The spring is extended and the tension pulley moves inwards,
so remove the old belt.
3. Install the new belt in the same way.

Replace the V-belts as a set.

The machine is equipped with an auto-tensioner, so there is no

need to carry out any adjustment until the belt is replaced.

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.

MAINTENENCE SERVICE PROCEDURE

EVERY 1000 HOURS SERVICE

Carry out maintenance for EVERY 250 HOURS and EVERY 500 HOURS SERVICE at the same time.

REPLACE CORROSION RESISTOR CARTRIDGE

All the engine parts are 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 the cartridge.

Filter wrench

1. Screw in 2 valves (1) at the top of the corrosion resistor.

2. Set the container to catch the water under the cartridge.
3. Using a filter wrench, remove cartridge (2).
4. Clean the filter holder, coat the seal surface of the new
cartridge thinly with engine oil, then install the cartridge.
5. When installing, tighten until the gasket contacts the seal
surface of the filter holder, then tighten a further 2/3 turns.
If the filter cartridge is tightened too far, the gasket will be
damaged and this will lead to leakage of water. If the filter is too
loose, water will also leak from the gap at the gasket, so always
tighten the correct amount.
6. Tighten 2 valves (1).
7. After replacing the cartridge, start the engine and check that there is no leakage of water from the filter seal
surface. If there is any leakage of water, check the tightening of the filter cartridge.

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.

SERVICE PROCEDURE MAINTENENCE

CHANGE OIL IN TRANSMISSION CASE, CLEAN TRANSMISSION CASE STRAINER

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.
When removing the oil filler cap, turn it slowly to release the internal pressure, then remove it.

Refill capacity: 190 liters (50.2 US gal)

Change the oil every 1000 hours or every 10,000 km, whichever comes sooner.
1. Set the container to catch the oil directly under the drain plug.
Remove drain plug (1), then loosen drain valve (2) slowly to
avoid getting oil on yourself, and drain the oil, then tighten the
plug again.

2. Remove bolt (3), then remove the cover and take out strainer
(4).
3. Remove any dirt stuck to the strainer, then wash in clean diesel
fuel or flushing oil. If the strainer is damaged, replace it.

4. After installing the strainer, add engine oil through oil filler (F)
to the specified level.

5. After adding oil, check that the oil is at the specified level. See
"CHECK OIL LEVEL IN TRANSMISSION CASE, ADD OIL
(PAGE 3-72)".

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.

MAINTENENCE SERVICE PROCEDURE

REPLACE TRANSMISSION AND REAR BRAKE COOLING OIL FILTER ELEMENT

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.
When removing the oil filler cap, turn it slowly to release the internal pressure, then remove it.

1. Turn the cap of oil filler (F) slowly to release the internal
pressure, then remove the cap.
2. Remove bolt (1), then remove cover (2).
3. Take out the element, then wash the inside of the case and the
removed parts.
4. Install the new element, then install cover (2) with bolt (1).

If the filter Maintenance caution lamp (if equipped) lights up when the engine water temperature gauge is in the white
range and the engine is running at 1200 to 2100 rpm, replace the element immediately.

4 - 53
.

SERVICE PROCEDURE MAINTENENCE

REPLACE BRAKE OIL FILTER ELEMENT

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.
When removing the oil filler cap, turn it slowly to release the internal pressure, then remove it.

Prepare a filter wrench

1. Depress the brake pedal at least 20 times to reduce the pressure inside the brake control accumulator to 0.

REMARK
When the pressure in the accumulator is released, the operating effort of the brake pedal becomes lighter and the
oil pressure noise disappears.

2. Remove the bolt, then remove accumulator cover (1), and put
a container to catch the drain oil under the brake oil filter.

3. Remove filter case (2).

4. Take out the element and wash the inside of the filter case.
Replace O-ring (3) and backup ring (4) on the filter case with
new parts, coat thinly with clean engine oil, then install.
5. Assemble a new element in the filter case, coat the O-ring of
the element thinly with clean engine oil, then install.
Tightening torque: 78.4 to 98N·m
(8 to 10kgf·m, 57.9 to 72.3 lbft)
6. Install accumulator cover (1).

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.

MAINTENENCE SERVICE PROCEDURE

LUBRICATION
1. Using a grease pump, pump in grease through grease fittings marked by arrows.
2. After greasing, wipe off any old grease that was pushed out.

(1) Transmission mount (1 point)

(2) Automatic suspension link (left and right: 1 point each)

(3) Tension pulley and fan pulley (3 points)

Pump in grease through the grease fitting until grease oozes out
from the seal.

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.

SERVICE PROCEDURE MAINTENENCE

CHECK WEAR OF REAR BRAKE DISC

Carry out this check when the brake oil temperature is below 60°C (140°F).
If the disc wear approaches the wear limit, check the condition frequently, regardless of the maintenance interval. In addition,
check the retarder capacity carefully.
Always carry out this operation with the engine stopped.

1. Stop the machine on level ground, set the parking brake switch to the PARKING position, then check that the
other brakes are not applied before starting inspection.
2. Remove cap nut (1).

3. Push in until rod (2) of the gauge contacts the piston. Do not
depress the brake pedal when doing this.
4. If slit (3) of rod (2) goes in beyond guide end face (4), it means
that the disc has reached the wear limit.
If this happens, please contact your Komatsu distributor for
inspection and maintenance.
5. Install cap nut (1) removed in Step 2.
Tightening torque: 128 to 186 N·m
(13 to 19 kgf·m, 94 to 137.4 lbft)

REMARK
On a new machine, the position of the guide is adjusted so that slit (5) comes to guide end face (4), so do not
loosen locknut (6) except when replacing the disc.
When the engine is started and the rod is pushed in, the rod is pushed back by the brake cooling oil pressure,
so carry out this operation with the engine stopped.

CHECK TIGHTENING PARTS OF TURBOCHARGER

Please contact your Komatsu distributor to have the tightening portions checked.

CHECK PLAY OF TURBOCHARGER ROTOR

Please contact your Komatsu distributor to have the rotor play checked.

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.

MAINTENENCE SERVICE PROCEDURE

EVERY 2000 HOURS SERVICE

Carry out maintenance for EVERY 250 HOURS, EVERY 500 HOURS and EVERY 1000 HOURS SERVICE at the
same time.

REPLACE STEERING, HOIST OIL TANK FILTER ELEMENT

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.
When removing the oil filler cap, turn it slowly to release the internal pressure, then remove it.

1. Turn the cap of oil filler (F) slowly to release the internal
pressure, then remove the cap.
2. Remove bolt (1), then remove cover (2).
3. Take out the element, then wash the inside of the case and the
removed parts.
4. Install the new element, then install cover (2) with bolt (1).

If the filter Maintenance caution lamp (if equipped) lights up when the engine water temperature gauge is in the white
range and the engine is running at 1200 to 2100 rpm, replace the element immediately.

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SERVICE PROCEDURE MAINTENENCE

CLEAN HYDRAULIC TANK STRAINER

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.
If there is still pressure remaining inside the case, the oil or plug may fly out. Turn the plug slowly to release the pressure, then
remove it carefully.

1. Lower the dump body and stop the engine.

2. Turn the cap of oil filler (F) slowly to release the internal
pressure.
3. Remove plug (1) of the strainer (2 places) at the rear of the left
front wheel.
4. Take the strainer out from strainer case (2), then wash it in
clean diesel fuel.
5. Tighten the cap of oil filler (F).

CHANGE OIL IN FINAL DRIVE CASE

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.
If there is still pressure remaining inside the case, the oil or plug may fly out. Turn the plug slowly to release the pressure, then
remove it carefully.

Refill capacity: Left, right 21 liters (5.6 US gal) each

1. Stop the machine so that the TOP casting mark is at the top
and drain plug (P) is at the bottom.
2. Remove drain plug (P), drain the oil, then tighten the plug
again.
3. Add engine oil through the hole for plug (G) to the specified
level.
4. After adding oil, check that the oil is at the specified level. See
"CHECK OIL LEVEL IN FINAL DRIVE CASE, ADD OIL
(PAGE 4-34)".

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MAINTENENCE SERVICE PROCEDURE

CHANGE OIL IN DIFFERENTIAL CASE

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.
If there is still pressure remaining inside the case, the oil or plug may fly out. Turn the plug slowly to release the pressure, then
remove it carefully.

Refill capacity: 95 liters (25.1 US gal)

1. Remove drain plug (P), drain the oil, then tighten the plug
again.
2. Add engine oil through the hole in plug (G) to the specified
level.
3. After adding oil, check that the oil is at the specified level. See
"CHECK OIL LEVEL IN DIFFERENTIAL CASE, ADD OIL
(PAGE 4-34)".

CLEAN DIFFERENTIAL CASE BREATHER

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.

Remove the mud and dirt from around the breather, then remove
the breather and wash out the dirt from inside with clean diesel oil
or flushing oil.

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.

SERVICE PROCEDURE MAINTENENCE

CLEAN ENGINE BREATHER ELEMENT

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 off the dirt from around the breather.

2. Remove the breather from the cylinder block.
3. Rinse the whole breather in diesel oil or flushing oil.

4. After washing, pass diesel oil through in direction (A).

5. Dry with compressed air, then coat the O-ring with engine oil,
and install.
Check the element and O-ring, and replace them with new
parts if necessary.

CHECK ALTERNATOR, STARTING MOTOR

The brush may be worn or may be no grease on the bearing, so contact your Komatsu distributor for inspection or
repair.
If the engine is started frequently, carry out inspection every 1000 hours.

CHECK, ADJUST ENGINE VALVE CLEARANCE

Special tools are needed for the inspection and maintenance, so please contact your Komatsu distributor to have
this work carried out.

CLEAN, CHECK TURBOCHARGER

Contact your Komatsu distributor for cleaning and inspection.

CHECK ACCUMULATOR GAS PRESSURE

When carrying out the EVERY 2000 HOURS SERVICE or EVERY YEAR SERVICE or when making periodic
replacement of the critical safety parts, please ask your Komatsu distributor to check the accumulator gas pressure.

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MAINTENENCE SERVICE PROCEDURE

EVERY 4000 HOURS SERVICE

Maintenance for every 250, 500, 1000 and 2000 hours service should be carried out at the same time.

CHANGE OIL IN STEERING, HOIST OIL TANK

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.
When removing the oil filler cap, turn it slowly to release the internal pressure, then remove it.

Refill capacity: 122 liters (32.2 US gal)

1. Lower the dump body and stop the engine.

2. Turn the cap of oil filler (F) to release the internal pressure
before removing the cap.
3. Remove drain plug (1), then loosen drain plug (2) slowly to
avoid getting oil on yourself, and drain the oil.
4. Add engine oil through oil filler (F) to the specified level.
5. After adding oil, check that the oil is at the specified level. See
CHECK OIL LEVEL IN STEERING AND HOIST OIL TANK,
ADD OIL (PAGE 3-72).

CHECK WATER PUMP

Check for play in the pulley, leakage of grease or water, or clogging of the drain hole. If any abnormality is found,
contact your Komatsu distributor for disassembly and repair or replacement.

CHECK FAN PULLEY AND TENSION PULLEY

Check for play of the pulley and leakage of grease. If any abnormality is found, please contact your Komatsu
distributor.

CHECK VIBRATION DAMPER

There is the possibility of drop in the level of the damper fluid and runout of the concave surface. So, please contact
your Komatsu distributor to inspect or replace.

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SERVICE PROCEDURE MAINTENENCE

EVERY 6000 HOURS SERVICE

Maintenance for every 50, 250, 500, 1000, 2000 and 4000 hours service should be carried out at the same time.

LUBRICATE DRIVE SHAFT

If special drive shaft grease is used, carry out greasing every 6000
hours or every 2 years.

1. Using a grease pump, pump in grease through the grease

fittings marked by the arrows.
2. Grease the spider portion until grease comes out from the cap
seal.
3. After greasing, wipe off any old grease that was pushed out.

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