Komatsu PC1250-11 Original Instructions Manual page 351

MAINTENANCE
• Rear side swing motor
1)
Run the engine at low idle, remove the hose (1) at port S, and check that oil oozes out from the hose
(1) at port S.
NOTICE
At this time, do not perform the swing operation.
2)
If oil does not ooze out, stop the engine, remove the port S hose (1), and fill the motor case with hy-
draulic oil.
3)
After bleeding air, install the hose (1) at port S.
4)
Run the engine at low idle and slowly swing at least 2 turns uniformly to the right and left.
NOTICE
If the air is not bled from the swing motor, the motor bearings will be damaged.
5.
Bleeding air from attachment (when installed)
If an attachment is installed, operate the attachment pedal repeatedly (approximately 10 times) with the en-
gine running at low idle until the air is completely bled from the attachment circuit.
NOTICE
• If the attachment has its own air bleeding procedure specified by the manufacturer, observe
them.
• After completing the air bleeding operation, stop the engine, leave the machine for 5 minutes,
and then start the operation. This will remove the air bubbles in the oil inside the tank.
• Check for oil leakage and wipe off any spilled oil.
6.
Bleeding air from travel motor circuit
If the piping of the travel motor is removed once and as-
sembled again afterwards, run the engine at low idle, and
perform the following to bleed air from the circuit.
1)
Start the engine, and run it at low idle.
2)
Remove the travel motor cover (1), and loosen the air
bleeding plug (2) 1 turn.
NOTICE
Never loosen the plug (2) more than 1 turn.
3)
Operate the fine control of the travel lever forward and
reverse for 4 to 5 times.
4)
When oil which is not milky white comes out through
the air bleeding plug (2), tighten the air bleeding plug
(2).
5)
Install the travel motor cover.
MAINTENANCE PROCEDURE
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