MAINTENANCE PROCEDURE

Check Operating Condition Of Compressor

Ask your Komatsu distributor to carry out the inspection.

Check Starting Motor

Ask your Komatsu distributor to have the starting motor checked. If the engine is started frequently, have this inspection performed every 1000 hours.

Every 5000 Hours Maintenance

Maintenance for every 10, 100, 250, 500, and 1000 hours of service should be performed at the same time.

Change Oil In Hydraulic Tank

Warning

Immediately after the engine is stopped, its parts and oil are still very hot, and may cause burn injury. Accordingly, wait until they have cooled down before starting the work. When removing the oil filler cap, turn it slowly to release the internal pressure, then remove it.

Refill capacity: 470 liters (124.2 US gal) Prepare a handle (for the socket wrench).

1. Swing the upper structure so that hydraulic tank drain plug (P3) and drain plug (P1) at the bottom of the pump suction tube are in the middle between the left and right tracks.

2. Retract the arm and bucket cylinders, then lower the boom and put the teeth in contact with the ground.

3. Set the lock lever to LOCK position and stop the engine.

Maintenance Procedure

4. Remove the cap from oil filler (F) on top of the hydraulic tank.

5. Place a container to receive drained oil under the drain plug located in the underpart of the machine. Remove drain plug (P1) on the suction tube and then loosen (P2) to drain oil. After draining oil from drain plug (P1), remove drain plug (3) under the hydraulic tank and drain plug (P4) on the suction tube to drain remaining oil.

6. Check the O-rings fitted to drain plugs (P3) and (P4) for any damage. If any, replace the defective O-ring with a new one. After draining oil, tighten drain plugs (P1), (P2), (P3) and (P4).

Tightening torque

(P1) and (P2): 152 ± 24.5 Nm (15.5 ± 2.5 kgm, 112.1 ± 18.1 lbft)

(P3) and (P4): 68.6 ± 9.8 Nm (7 ± 1 kgm, 50.6 ± 7.2 lbft)

When removing drain plug (P3), (P4), be careful not to get oil on yourself.

7. Add the specified amount of new and clean oil through oil filler port (F). Check that the oil level is between H and L on the sight gauge.

For details of oil level check, see "Check Oil Level in Hydraulic Tank, Add Oil (PAGE 3-91)".

8. Bleed the air from the circuit after cleaning or replacing the filter element or strainer, or after changing the oil. For details of the method of bleeding the air, see "BLEEDING AIR FROM HYDRAULIC SYSTEM (PAGE 4-38)".

Check And Tighten Swing Circle Bolts

If the machine is operated with loose swing circle bolts (A) and (B), they will be broken. Retighten the bolts whenever they are found loose.

Tightening

1. Tightening procedure of swing circle bolt (A)

1) Open the grease pump box at the right side of the machine, then remove spare grease can holder cover (1) and spare grease can.

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

REMARK

When cover (3) does not come off easily, insert removed bolt (2) into tapped bolt hole (4) and then remove cover (3).

3) Fit the socket wrench (width across flats b = 46 mm) and extension bar to bolt (A) and tighten it.