Komatsu H75051, Operation & Maintenance Manual

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NOTICE
• Before starting the engine, check that the oil level is between the marks (C) and (D) on the side
of dipstick which has a stamped mark of “COLD STOP”.
• When checking the oil level, start the engine first. After finishing the warm-up operation of the
transfer, perform the final check by using the side of dipstick which has a stamped mark of
“HOT IDLE”.
10. Check the transfer case for oil leakage.
METHOD FOR REPLACING HST OIL FILTER CARTRIDGE
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WARNING
• Immediately after the engine is stopped, its parts and oil are still very hot and may cause burn in-
jury. Wait for the temperature to go down, and then start the work.
• When removing the oil filler cap, the oil may spurt out. Turn it slowly to release the internal pres-
sure, then remove it carefully.
Items to be prepared
• Container to catch the drained oil
• Filter wrench
1.
Loosen the bolts (1) (4 pieces) and remove the cover (2).
2.
Turn the filter cartridge (3) counterclockwise by using the
filter wrench, and remove it.
3.
Clean the filter head and install the new filter cartridge.
When installing the cartridge, tighten it until the packing
surface contacts the seal surface of the filter holder, then
tighten it 1/2 of a turn by using the filter wrench.
Tightening torque : 29 to 39 Nm {3.0 to 4.0 kgm}
4.
Run the engine at low idle for 5 minutes to bleed air from
the HST circuit.
5.
Check the hydraulic oil level.
After adding oil, check that the oil is at the specified level by referring to “METHOD FOR CHECKING OIL
LEVEL IN HYDRAULIC TANK, ADDING OIL (4-46)”.
6.
Run the engine at low idle, and extend and retract each of the steering, bucket, and boom cylinders 4 to 5
times, taking care not to move them to the stroke end (stop them approximately 100 mm short of the stroke
end).
NOTICE
If the engine is run at high speed immediately after the startup or a cylinder is pushed up to its
stroke end, air taken inside the cylinder may cause damage to the piston packing, etc.
7.
Extend and retract each of the steering, bucket, and boom cylinders to the stroke end 3 to 4 times.
8.
Stop the engine, loosen the cap of the oil filler port, and bleed air from the hydraulic tank.
MAINTENANCE MAINTENANCE PROCEDURE
4-63