Komatsu PC1250-11, Original Instructions Manual

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NOTICE
Komatsu recommends using genuine Non-Amine Engine Coolant (AF-NAC) for the coolant.
Non-Amine Engine Coolant (AF-NAC) is already diluted with distilled water, so it is not flammable.
Check the density with a coolant tester.
Prepare a container whose capacity is larger than the specified coolant volume to catch the drained coolant.
1.
Place the machine on a level ground, then stop the engine.
2.
Remove the cover (1).
3.
Check that the coolant temperature is low enough to touch
the radiator cap surface by bare hand, turn the radiator
cap (2) slowly until it hits the stopper, and release the pres-
sure.
4.
Then, while pushing the radiator cap (2), turn it until it
touches the stopper, and remove it.
5.
Remove the drain valve cover (3) on the radiator side and
drain valve cover (4) on the engine side.
6.
Install the drain hose (6) to the drain valve (5) on the radia-
tor side.
7.
Place the containers under drain valve (5) on the radiator
side and drain valve (7) on the engine side to catch the
coolant water.
Open the drain valve (5) and (7), and drain the coolant.
8.
After the coolant is drained, close the drain valves (5) and
(7), and add the tap water. After the radiator is filled with
water, start the engine, and run it at low idle for approxi-
mately 10 minutes.
9.
Stop the engine and open the drain valves (5) and (7) to
drain the water.
10. After draining the water, clean with detergent liquid.
For the cleaning method, follow the usage instruction for
the detergent liquid.
11. Close the drain valves (5) and (7).
12. Remove the drain hose (6)
．
13. Install the covers (3) and (4).
14. Add coolant through the filler port up to the mouth of the
port.
For the coolant density, see “Coolant density table”.
15. Run the engine at low idle for 5 minutes to remove the air from the coolant, then run it at high idle for further
5 minutes.
MAINTENANCE PROCEDURE MAINTENANCE
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