WARNING Antifreeze is flammable, so keep it away from any flame

! Use city water for the cooling water.

For water requirements, see 18.1.3 COOLANT on page 3-6.

WARNING

WHEN REQUIRED 24. SERVICE PROCEDURE

3-29

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

! Prepare a container to catch drained coolant: Min 24 O capacity.

1. Turn radiator cap · slowly to remove it.

3. Remove the undercover, then set a container to catch the coolant under drain valve ¸ and drain plug ¹. Open drain valve ¸ at the bottom of the radiator to drain the water. Remove drain plug ¹ in the cylinder block when draining the water. Open cab heater water valve.

4. After draining the water, close drain valve ¸ and drain plug ¹, and fill with city water.

5. Open drain valve ¸ and drain plug ¹ run the engine at low idle, and flush water through the system for 10 minutes.

When doing this, adjust the speed of filling and draining the water so that the radiator is always full.

While flushing water through the system, watch carefully that the water inlet hose does not come out of the radiator water filler.

6. After flushing, stop the engine, open drain valve ¸ and drain plug ¹, then close it again after all the water has drained out.

7. After draining the water, clean with a flushing agent.

We recommend use of a genuine Komatsu cleaning agent. For details of the cleaning method, see the instructions given with the cleaning agent.

8. After cleaning, open drain valve ¸ and drain plug ¹ to drain all the cooling water, then close them and fill slowly with clean water.

9. When the water comes up to near the water filler port, open drain valve ¸ and drain plug ¹, run the engine at low idle, and continue to run water through the system until clean colorless water comes out.

When doing this, adjust the speed of filling and draining the water so that the radiator is always full.

10. When the water is completely clean, stop the engine, close drain valve ¸, wrap the drain plug with seal tape, then close drain plug ¹.

Close cab heater water valve.

11. Open after-cooler air drain valves ». 12. Install the undercover.

13. Add coolant until it overflows from the coolant filler. When the coolant comes up to near the water filler port, close the after-cooler air drain valves ».

14. To remove the air in the coolant, run for five minutes at low idle, then for another five minutes at high idle. When doing this, leave radiator cap · off.

15. After draining off the coolant from the reserve tank º, clean the inside of the reserve tank and refill with coolant to between FULL and LOW level.

16. Stop the engine, wait for about three minutes, add coolant up to near the radiator filler port, then tighten cap ·.

WHEN REQUIRED 24. SERVICE PROCEDURE

3-31 24.2.3 CHECK AND TIGHTEN TRACK SHOE BOLTS

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

Method for tightening (For PC200, 200LC, 210LC, 220LC)

1. First tighten to a tightening torque of 490 ± 50 Nm (50 ± 5 kgm) then check that the nut and shoe are in close contact with the link's contact surface.

2. After checking, tighten an additional 120E ± 10E.

Method for tightening (For PC250LC)

1. First tighten to a tightening torque of 200 ± 20 Nm (20 ± 2 kgm) then check that the nut and shoe are in close contact with the link's contact surface.

2. After checking, tighten an additional 120E ± 10E.

Order for tightening

Tighten the bolts in the order shown in the diagram on the right. After tightening, check that the nut and shoe are in close contact with the link's mating surface.

24.2.4 CHECK AND ADJUST TRACK TENSION WARNING

Carry out this operation with two workers. The operator must move the machine in accordance with the signals from the other worker. The track tension is checked with the chassis raised, so it is extremely dangerous if the machine is lowered by mistake during the inspection. Never move the machine while anyone is carrying out measurements.

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

1. Raise the chassis with the boom and arm.

When doing this, operate the levers slowly.

2. Measure the clearance between the bottom of the track frame and the top of the track shoe at a position that is safe even if the chassis should come down.

Standard clearance: "S"

PC200, 200LC, 210LC, 220LC: 303 ± 20 mm PC250LC: 331 ± 20 mm

Places to measure

PC200:4th track roller from sprocket PC200LC:5th track roller from sprocket PC210LC:5th track roller from sprocket

PC220LC:Between 5th and 6th track roller from sprocket PC250LC:Between 4th and 5th track roller from sprocket

WHEN REQUIRED 24. SERVICE PROCEDURE

3-33 If the track tension is not at the standard value, adjust it in the following

manner.

Adjustment

WARNING