Komatsu WA250PT-5H, Operation & Maintenance Manual

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MAINTENANCE
Service procedure
When required
4-25
Mixing rate of water and antifreeze
WARNING
Antifreeze is flammable, so keep it away from flame.
Antifreeze is toxic. When removing the drain plug, be careful not to get water containing antifreeze on
you. If it gets in your eyes, flush your eyes with large amount of fresh water and see a doctor at once.
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 the following:
Container to mix the coolant: Min 1
9 liters ( 5 . 02 US gal) capacity
Prepare a water inlet hose.
1. Stop the engine.
2. To loosen and remove the radiator cap, use a suitable
climbing aid (for example a ladder) to climb up the back of
the machine.
3. Check that the cooling water temperature has gone down
enough to make it possible to touch the radiator cap surface
by hand, then turn radiator cap (1) slowly until it contacts the
stopper to release the pressure.
4. Following this, push radiator cap (1), turn it until it contacts
the stopper, then remove it.
5. Set a container in position to catch drained antifreeze mix-
ture, then open valve (2) under the radiator to drain cooling
water.
6. After draining the water, close drain valve (2) and fill with tap
water.
7. When the radiator is full, start the engine, and run it at low
idling.
Keep the engine running at low idling for 10 minutes until
the water temperature reaches more than 90°C (194°F).
8. Stop the engine, open drain valves (2), drain the water, then
tighten them again.
9. After draining the water, clean the cooling system with
cleaning agent.
For the cleaning method, see the instructions for the clean-
ing agent.
10.Decide the proportions of antifreeze and water according to
the table for the mixing rate of water and antifreeze.
Min. atmospheric
temperature
°C -10 -15 -20 -25 -30
°F 14 5 -4 -13 -22
Amount of anti-
freeze
Liter 5.70 6.84 7.79 8.74 9.50
US gal 1.51 1.81 2.06 2.31 2.51
Amount of water
Liter 13.30 12.16 11.21 10.26 9.50
US gal 3.51 3.21 2.96 2.71 2.51