General • Inspections

Komatsu Bulldozer D155AX-5: WHEN REQUIRED MAINTENANCE

Use this maintenance checklist and follow the schedule interval for the proactive and preventive maintenance of your bulldozer. This has been proven to lower costs by catching small service issues before they blossom into giant repair headaches.

MaintainX

11/04/2022

Komatsu Bulldozer D155AX-5: WHEN REQUIRED MAINTENANCE

CLEAN INSIDE OF COOLING SYSTEM

Use a permanent type of antifreeze.

If, for some reason, it is impossible to use permanent type antifreeze, use an antifreeze containing ethylene glycol.

Super Coolant (AF-ACL) has an anti-corrosion effect as well as an antifreeze effect.

The ratio of antifreeze to water depends on the ambient temperature, but to obtain the corrosion resistance effect, a minimum ratio of 30% by volume is necessary.

When deciding the ratio of antifreeze to water, check the lowest temperature in the past, and decide from the mixing rate table given below.

It is actually better to estimate a temperature about 10oC lower when deciding the mixing rate.

Mixing rate of water and antifreeze

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.

Prepare a container to catch drained coolant: Min 101 liters capacity.

Stop the engine, then turn valve (1) of corrosion resistor (2) to the CLOSE stopper position.

Turn cap (3) of the radiator water filler slowly.

Set a container to catch the coolant under engine coolant drain valve (4) at the bottom of the radiator.

Open drain valve (4) and drain the water.

After draining the water, tighten drain valve (4), and fill with city water. When the radiator is full, start the engine and run at low idling.

Open drain valve (4), keep the engine running at low idling, and flush for 10 minutes. When flushing, adjust the amount of water poured in and drained to ensure that the radiator is always full of water. Always check that the hose has not come off the radiator cap during the flushing operation.

After flushing, stop the engine, stop the flow of water, then drain the water and close drain valve (4).

After draining the water, clean the radiator with detergent. When carrying out the flushing operation, follow the instructions given with the flushing agent.

After flushing, open drain valve (4), drain all the water, then close the drain valve and add city water up to near the water filler port.

When the water reaches near the water filler port, open drain valve (4), run the engine at low idling, and carry out the flushing operation until clean water comes out. When flushing, adjust the amount of water added and drained to ensure that the radiator is always full of water.

When clean water comes out, stop the engine and close drain valve (4).

Replace the corrosion resistor, and turn valve (1) to the OPEN stopper position. For details of the method for replacing the corrosion resistor cartridge, see "REPLACE CORROSION RESISTOR CARTRIDGE (PAGE 4-62)".

Fill with antifreeze and city water until the water overflows from the water filler. Determine the proportions of antifreeze and water in accordance with the water and antifreeze mixture table.

Run the engine idle at a low speed for 5 minutes, then at a high speed for 5 minutes to bleed air mixed in the cooling water. (At this time, keep the water filler cap removed.)

Drain the cooling water inside sub-tank (5), clean the inside of the sub-tank,then fill again with cooling water to a point midway between the FULL and LOW marks.

Stop the engine,wait for 3 minutes,add city water until the water level reaches near the water filler port,then tighten the cap (3).

CHECK, CLEAN AND REPLACE AIR CLEANER ELEMENT

CHECK

When the yellow display panel indicating the pressure of dust indicator (1) goes over the red line, clean the air cleaner ele-ment.

CLEAN, REPLACE OUTER ELEMENT

Loosen wing nut (4), then remove the outer element.

Clean the air cleaner body interior.

Direct dry compressed air (less then 700 kPa (7 kg/cm2 , 100 psi)) to the element from inside along its folds,then direct it from outside along its folds and again from inside.

Remove one seal from the outer element. The number of times the outer element has been cleaned can be seen by the number of removed seals.
Replace the outer element which has been cleaned 6 times repeatedly or used throughout a year. Replace the inner element at the same time.
Replace the element when the air cleaner clogged warning lamp lights up soon after installing the cleaned element even though it has not been cleaned 6 times.
Check inner element mounting nuts for looseness and, if necessary, retighten.
Replace seal washer (5) or wing nut (4) with new parts if they are broken.

Set the cleaned element.

REPLACING INNER ELEMENT

First remove the outer element, and then remove the inner element.

To prevent dust from getting in,use a clean cloth or tape to cover the air connector (outlet side).

Clean the air cleaner body interior,then remove the cover installed in Step 2.

Fit a new inner element to the connector and tighten it with nuts. Do not clean and reinstall a inner element.

Install the outer element.

After replacing the element, press dust indicator reset button (3) to return the yellow display panel to its original position.

CHECK ELECTRICAL INTAKE AIR HEATER

Before the start of the cold season (once a year), contact your Komatsu distributor to have the electrical intake air heater repaired or checked for dirt or disconnections.

CHECK TRACK TENSION

The wear of pins and bushings on the undercarriage will vary with the working conditions and soil properties. It is thus necessary to continually inspect the track tension so as to maintain the standard tension. Carry out the check and adjustment under the same conditions as when operating (on jobsites where the track becomes clogged with mud, measure with the track clogged with mud).

INSPECTION

Stop the machine on level ground (stop with the transmission in FORWARD without applying the brake). Then place a straight bar on the track shoes between the carrier roller and the idler as shown in the diagram, and measure the clearance between the bar and the grouser at the midpoint. If the clearance is 20 to 30 mm, the tension is standard.

If the track tension is not at the standard value,adjust it in the following manner.

When increasing tension

Remove both bolts (3), then remove cover (2).

Pump in grease through the grease fitting with a grease pump.

To check that the correct tension has been achieved, move the machine backwards and forwards.

Check the track tension again,and if the tension is not correct, adjust it again.

Continue to pump in grease until S becomes 0 mm. If the tension is still loose, the pin and bushing are excessively worn, so they must be either turned or replaced. Please contact your Komatsu distributor.

When loosening tension

Remove both bolts (3), then remove cover (2).

Loosen lubricator (1) gradually to release the grease.

Turn lubricator (1) a maximum of one turn.

If the grease does not come out smoothly, move the machine backwards and forwards a short distance.

Tighten lubricator (1).

To check that the correct tension has been achieved, move the machine backwards and forwards.

Check the track tension again, and if the tension is not correct, adjust it again.

When removing track

CHECK AND TIGHTEN TRACK SHOE BOLTS

If the machine is used with track shoe bolts (1) loose, they will break, so tighten any loose bolts immediately.

Method for tightening (shoe bolt)

First tighten to a tightening torque of 588 ± 58.8 N•m (60 ± 6 kgf•m) then check that the nut and shoe are in close contact with the link contact surface.
After checking, tighten a further 120 ± 10°.

Method for tightening (master link connecting bolt)

First tighten to a tightening torque of 392 ± 39.2 Nm (40 ± 4 kgm) then check that the link contact surfaces are in close contact.
After checking, tighten a further 180 ± 10°.

Order for tightening

Tighten the bolts in the order shown in the diagram on the right.

REVERSE AND REPLACE THE END BITS AND CUTTING EDGES

Reverse or replace the end bits and cutting edges before it is worn out to the blade end.

Raise the blade to a proper height and apply a block to the frame so as to prevent fall of the blade.
Operate the safety lever to the LOCK position.
Measure the wear of the end bit and cutting edge in accordance with the wear standards given below.
Remove the cutting edge and the end bit and clean the mounting surface.
Reverse or replace the cutting edge and the end bit when worn out.
After several hours of running, retighten the nuts.

Wear standards

The symbols in the work equipment column have the following meaning.

A: Semi-U blade, U blade

B: Angledozer

If bolt (2) and nut (1) are damaged, replace them with new ones at the same time.

Loosen nuts (1), remove bolts (2), then replace or reverse the cutting edge.

Install the edge to the blade and tighten temporarily. Lower the blade and push it against the ground to remove the play in bolt (2), then tighten to the correct tightening torque.

When installing end bit (3), bring top edge (4) of the end bit into tight contact with stopper (5), then tighten the bolts.

CLEAN, CHECK RADIATOR FINS

If the radiator fins are clogged or dirty, clean and inspect them.

Remove bolts (1) (4 bolts).
Open the A side (hinge side)of the radiator mask. It opens approx. 30 mm.
Leave the B side of the radiator mask open.
Open the hydraulic cooler. For details of the opening method, see "CLEAN, CHECK HYDRAULIC COOLER FINS (PAGE 4-34)".
Clean the radiator fins clogged with mud,dust and leaves with compressed air. Steam or water may be used instead of compressed air.
When closing the radiator mask, always push in the A side first, then push in the B side, align the bolt holes, and tighten bolt (1).

REPLACE AIR CONDITIONER BELT

Loosen 4 bolts (1) and jack bolt (2), then move compres- sor (3) to the side.

Replace the V-belt.

When adjusting the V-belt, do not push the compressor directly with a bar. Use jack bolt (2).

Tighten jack bolt (2) and bolts (1), and apply tension to the V-belt.

The standard deflection for the V-belt is approx. 10 mm when the belt is pushed by thumb (approx. 6 kg) at a point midway between the air compressor pulley and fan pulley.

CLEAN, CHECK HYDRAULIC COOLER FINS

If the hydraulic cooler fins are clogged or there is dirt caught in the fins, clean and check the fins.

Open the radiator mask. For details on how to open the radiator mask, see "CLEAN, CHECK RADIATOR FINS (PAGE 4-32)".

Set the hinge pin in position.

Top Extend pin bolt (1), and when it penetrates plate (2) (welded to the hydraulic cooler) by 8 mm, set nut (9) in position.
Bottom Extend pin bolt (4), and when it penetrates plate (5) by 8 mm, set double nut (3) in position.

Remove cooler mounting bolts (6) (x 4) and (7) (x 4), and hose clips (8).

Open the hydraulic cooler to the hinge side,then clean and check the fins. The hydraulic cooler can be opened approx. 40°.

Use compressed air to remove the mud,dirt, and leaves clogging the hydraulic cooler fins. Steam or water may be used instead of compressed air.

When fixing the hydraulic cooler in position again:

Fix the hydraulic cooler in position with bolts (6) and (7), then fix the hose in position with clamp (8).
Retract pin bolts (1) and (4) and set so that there is a clearance of 5 - 10 mm at the top from plate (2) and at the bottom from plate (5).

CLEAN, CHECK AIR CONDITIONER CONDENSER FINS

If the air conditioner condenser fins are clogged, clean and check the fins.

Remove 3 mounting bolts (1) of the upper cover, then remove upper cover (2).
Use compressed air to blow off the mud, dirt, or leaves clogging the fins.
Install upper cover (2) with bolts (1).

ADJUST IDLER CLEARANCE

Since the idlers are forced to move forward and backward by an external force, guide plates (2) will be worn out. Wear of these plates will cause the vibration of idlers from side to side or inclination of the idlers, and running off of track links from the idlers or unevenly worn idler and links may result. Therefore, adjust the idlers according to the following procedure.

ADJUSTMENT

Drive the machine on level ground for 1 - 2 m, then remove covers (3) (both inside and outside) at the side face of the idler.

Measure the clearance A (4 locations: left, right, inside and outside) between the track frame and the guide plate.

If the clearance A exceeds 3.0 mm, loosen bolt (1), and pull out the shim to adjust the clearance at one end to 0.5 - 1.0 mm.

CHECK UNDERCARRIAGE OIL

Stop the machine on level ground, and check for any reduction in the oil at the idler (portion P), track roller (portion Q), bogie shaft (portion Q), and carrier roller (portion R).

Loosen seal bolt (1) slowly and check if oil oozes out from the thread. If oil oozes out, the oil level has not gone down, so tighten the bolt.

If no oil comes out even when seal bolt (1) is removed, the oil level is low, so please contact your Komatsu dis- tributor for repair.

REMARK

On the idler, seal bolt (1) cannot be seen unless outside cover is removed.

There is one bogie shaft seal bolt (1) each on the inside and outside.

CLEAN AIR CONDITIONER AIR FILTER

If the air conditioner air filter is clogged or there is dirt or dust in it, clean the filter.

Open inspection cover (1), open cover (2), then remove FRESH filter (3).

Open inspection cover (4) under the front panel, pull up RECIRC filter (5), and remove it.

Clean filters (3) and (5) with compressed air. If there is oil stuck to the filter, or it is extremely dirty, wash it in a neu- tral detergent. After washing it, dry it completely before installing it again.

REMARK

If the clogging of the filter cannot be removed by blowing with compressed air or washing in water, replace the filter with a new part.

CHECK, ADJUST AIR CONDITIONER

CHECKING TENSION OF COMPRESSOR BELT

If the belt is loose, it will slip and the cooling effect will be reduced. From time to time, press a point midway between the drive pulley and compressor pulley with your finger (approx.6 kg) and check that the tension is 10 mm. When the belt is new, there will be initial elongation, so always adjust again after 2 or 3 days.

CHECK LEVEL OF REFRIGERANT (GAS)

If the level of the refrigerant (gas) is low, the cooling effect will be reduced. Run the engine at high idling, and check the flow of the refrigerant in the refrigerant circuit through the sight glass of the receiver when the cooler is running at high speed.

No bubbles in refrigerant flow: Suitable (A)
Some bubbles in flow (bubbles pass continuously): Lack of refrigerant (B)
Colorless, transparent: No refrigerant (C)

REMARK

When there are bubbles,the refrigerant gas level is low, so contact your refrigerant dealer to have refrigerant added. If the air conditioner is run with the refrigerant gas level low, it will cause damage to the compressor.

New Freon R-134a is used as refrigerant.

GREASE DOOR HINGE (MACHINES EQUIPPED WITH CAB)

If the door makes a squeaking noise when it is opened or closed, spray lubricant in through the split in the hinge bushing. If the bushing is worn, replace the hinge.

CHECK DOOR LOCK STRIKER (MACHINES EQUIPPED WITH CAB)

If the wear of the doors lock striker exceeds 0.5 mm, replace the striker. If it is used at it is, the play will increase and this may result in breakage of the hinge or door lock.

CHECK DOOR LATCH

CHECK

Hold the door open-locked, and check that there is still grease inside the latch. If the amount of grease is low or there is no more grease, coat the inside of the latch with grease from por- tion (1).

REMARK

If there is no more grease inside the latch, the movement will become poor because of dust inside the latch, and the handle may be stiff when opening the door.

REPLACE DOOR DAMPER (MACHINES EQUIPPED WITH CAB)

If the depth of the door damper rubber groove is less than 2 mm, replace the damper. There are two dampers each at the top and bottom on the left and right doors.

CHECK WINDOW WASHER FLUID LEVEL, ADD FLUID (MACHINES EQUIPPED WITH CAB)

If there is air in the window washer fluid, check the level and add fluid. Open the battery cover, check the level of the fluid in window washer tank (1), and if it is low, add automobile window washer fluid. When adding fluid, be careful not to let dirt or dust get in.

REPLACE WIPER BLADE (MACHINES EQUIPPED WITH CAB)

If the blade is damaged, it will not wipe the window clean, so replace the blade.

Method of replacement

Front, rear wiper

Remove screw (1), then remove the blade.

Install a new blade, then tighten screw (1) securely.

Door wiper

It is hooked at portion (A), so move the blade in the direction of the arrow to remove it.

Install the new blade and hook it securely.

PROCEDURE FOR BLEEDING AIR IN HYDRAULIC SYSTEM

Bleeding air from cylinders

Run the engine at low idling, and extend and retract each cylinder 4 to 5 times. Do not operate the cylin- der to the end of its stroke. (Stop at a point approx. 100 mm before the end of the stroke.)

Next, operate each cylinder 3 to 4 times to the end of its stroke.

Finally, operate each cylinder 4 to 5 times to the end of its stroke to completely remove the air.

PROCEDURE FOR RELEASING INTERNAL PRESSURE OF HYDRAULIC SYSTEM

Stop the machine on firm level ground.

Lower the blde to the ground, then stop the engine.

Operate the blade control lever in each direction to the stroke end to release the internal pressure within 15 sec- onds after the engine is stopped.

Loosen oil filler cap (F) at the top of the hydraulic tank slowly to release the internal pressure.

Run the engine at low idling for about 5 seconds, and stop the engine. Move the blade control lever to back- ward, forward, right and left.

CLEAN INSIDE OF COOLING SYSTEM

CLEAN INSIDE OF COOLING SYSTEM

CLEAN INSIDE OF COOLING SYSTEM

Use a permanent type of antifreeze.

If, for some reason, it is impossible to use permanent type antifreeze, use an antifreeze containing ethylene glycol.

Super Coolant (AF-ACL) has an anti-corrosion effect as well as an antifreeze effect.

The ratio of antifreeze to water depends on the ambient temperature, but to obtain the corrosion resistance effect, a minimum ratio of 30% by volume is necessary.

When deciding the ratio of antifreeze to water, check the lowest temperature in the past, and decide from the mixing rate table given below.

It is actually better to estimate a temperature about 10oC lower when deciding the mixing rate.

Mixing rate of water and antifreeze

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.

Prepare a container to catch drained coolant: Min 101 liters capacity.

Stop the engine, then turn valve (1) of corrosion resistor (2) to the CLOSE stopper position.

Turn cap (3) of the radiator water filler slowly.

Set a container to catch the coolant under engine coolant drain valve (4) at the bottom of the radiator.

Open drain valve (4) and drain the water.

After draining the water, tighten drain valve (4), and fill with city water. When the radiator is full, start the engine and run at low idling.

Open drain valve (4), keep the engine running at low idling, and flush for 10 minutes. When flushing, adjust the amount of water poured in and drained to ensure that the radiator is always full of water. Always check that the hose has not come off the radiator cap during the flushing operation.

After flushing, stop the engine, stop the flow of water, then drain the water and close drain valve (4).

After draining the water, clean the radiator with detergent. When carrying out the flushing operation, follow the instructions given with the flushing agent.

After flushing, open drain valve (4), drain all the water, then close the drain valve and add city water up to near the water filler port.

When the water reaches near the water filler port, open drain valve (4), run the engine at low idling, and carry out the flushing operation until clean water comes out. When flushing, adjust the amount of water added and drained to ensure that the radiator is always full of water.

When clean water comes out, stop the engine and close drain valve (4).

Replace the corrosion resistor, and turn valve (1) to the OPEN stopper position. For details of the method for replacing the corrosion resistor cartridge, see "REPLACE CORROSION RESISTOR CARTRIDGE (PAGE 4-62)".

Fill with antifreeze and city water until the water overflows from the water filler. Determine the proportions of antifreeze and water in accordance with the water and antifreeze mixture table.

Run the engine idle at a low speed for 5 minutes, then at a high speed for 5 minutes to bleed air mixed in the cooling water. (At this time, keep the water filler cap removed.)

Drain the cooling water inside sub-tank (5), clean the inside of the sub-tank,then fill again with cooling water to a point midway between the FULL and LOW marks.

Stop the engine,wait for 3 minutes,add city water until the water level reaches near the water filler port,then tighten the cap (3).

CHECK, CLEAN AND REPLACE AIR CLEANER ELEMENT

CHECK

When the yellow display panel indicating the pressure of dust indicator (1) goes over the red line, clean the air cleaner ele-ment.

CLEAN, REPLACE OUTER ELEMENT

Loosen wing nut (4), then remove the outer element.

Clean the air cleaner body interior.

Direct dry compressed air (less then 700 kPa (7 kg/cm2 , 100 psi)) to the element from inside along its folds,then direct it from outside along its folds and again from inside.

Remove one seal from the outer element. The number of times the outer element has been cleaned can be seen by the number of removed seals.

Replace the outer element which has been cleaned 6 times repeatedly or used throughout a year. Replace the inner element at the same time.

Replace the element when the air cleaner clogged warning lamp lights up soon after installing the cleaned element even though it has not been cleaned 6 times.

Check inner element mounting nuts for looseness and, if necessary, retighten.

Replace seal washer (5) or wing nut (4) with new parts if they are broken.

Set the cleaned element.

REPLACING INNER ELEMENT

First remove the outer element, and then remove the inner element.

To prevent dust from getting in,use a clean cloth or tape to cover the air connector (outlet side).

Clean the air cleaner body interior,then remove the cover installed in Step 2.

Fit a new inner element to the connector and tighten it with nuts. Do not clean and reinstall a inner element.

Install the outer element.

After replacing the element, press dust indicator reset button (3) to return the yellow display panel to its original position.

CHECK ELECTRICAL INTAKE AIR HEATER

Before the start of the cold season (once a year), contact your Komatsu distributor to have the electrical intake air heater repaired or checked for dirt or disconnections.

CHECK TRACK TENSION

INSPECTION

If the track tension is not at the standard value,adjust it in the following manner.

When increasing tension

Remove both bolts (3), then remove cover (2).

Pump in grease through the grease fitting with a grease pump.

To check that the correct tension has been achieved, move the machine backwards and forwards.

Check the track tension again,and if the tension is not correct, adjust it again.

Continue to pump in grease until S becomes 0 mm. If the tension is still loose, the pin and bushing are excessively worn, so they must be either turned or replaced. Please contact your Komatsu distributor.

When loosening tension

Remove both bolts (3), then remove cover (2).

Loosen lubricator (1) gradually to release the grease.

Turn lubricator (1) a maximum of one turn.

If the grease does not come out smoothly, move the machine backwards and forwards a short distance.

Tighten lubricator (1).

To check that the correct tension has been achieved, move the machine backwards and forwards.

Check the track tension again, and if the tension is not correct, adjust it again.

When removing track

CHECK AND TIGHTEN TRACK SHOE BOLTS

If the machine is used with track shoe bolts (1) loose, they will break, so tighten any loose bolts immediately.

Method for tightening (shoe bolt)

First tighten to a tightening torque of 588 ± 58.8 N•m (60 ± 6 kgf•m) then check that the nut and shoe are in close contact with the link contact surface.

After checking, tighten a further 120 ± 10°.

Method for tightening (master link connecting bolt)

First tighten to a tightening torque of 392 ± 39.2 Nm (40 ± 4 kgm) then check that the link contact surfaces are in close contact.

After checking, tighten a further 180 ± 10°.

Order for tightening

Tighten the bolts in the order shown in the diagram on the right.

REVERSE AND REPLACE THE END BITS AND CUTTING EDGES

Reverse or replace the end bits and cutting edges before it is worn out to the blade end.