Komatsu PC30MR-5 Operation & Maintenance Manual page 275

MAINTENANCE
7.
Place containers to catch the coolant under the drain hose
installed to the drain valve (6) and under the coolant drain
plug (7) of the engine block.
8.
Open the drain valve (6) and remove the drain plug (7) to
drain the coolant.
9.
After draining the coolant, close the drain valve (6) and the
drain plug (7).
10. Fill the radiator with tap water.
Add tap water until it fills the radiator.
11. Start the engine and run it at low idle.
Continue running the engine at low idle for 10 minutes.
12. Stop the engine.
13. Open the drain valve (6) and remove the drain plug (7) to drain the tap water.
14. After draining the tap water, close the drain valve (6) and wrap the drain plug (7) with seal tape, and close
it.
15. Add coolant through the water filler port up to the mouth of the port.
For the coolant density, see preceding "Mixing proportion table of water and coolant".
16. Run the engine at low idle for 5 minutes to remove the air from the coolant, then run at high idle for a further
5 minutes.
Keep the radiator cap (5) removed during the above operations.
17. Drain the coolant in the reservoir tank (8).
18. Clean the inside of the reservoir tank (8).
19. Add coolant up to the middle between FULL and LOW.
20. Stop the engine.
21. Approximately 3 minutes later, add coolant to near the
mouth of the water filler port.
22. Tighten the radiator cap (5) securely.
23. Close the cooling cover (3).
24. Close the engine rear cover (1).
WENAM00150
MAINTENANCE PROCEDURE
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