Komatsu PC290LC-11 Operation & Maintenance Manual page 379

MAINTENANCE
METHOD FOR BLEEDING AIR FROM SWING MOTOR
NOTICE
• When bleeding air, do not operate the swing.
• If the air is not bled from the swing motor, the motor bearings may be damaged.
1.
Run the engine at low idle, loosen hose (3) at port S, and
check that oil oozes out from port S hose (3).
2.
If oil does not ooze out, stop the engine, remove port S
hose (3), and fill the motor case with hydraulic oil.
3.
After completely bleeding the air from the swing motor,
tighten port S hose (3).
4.
Run the engine at low idle.
5.
Swing evenly and slowly at least 2 turns each clockwise
and counterclockwise.
This will automatically bleed the air from the swing circuit.
When replacing the swing motor safety valve, ask your Komatsu distributor for the replacement and the air
bleeding.
METHOD FOR BLEEDING AIR FROM TRAVEL MOTOR
Bleed air only when the oil inside the travel motor case is drained.
1.
Run the engine at low idle, loosen air bleeder (4), and
tighten it when oil flows out.
2.
Run the engine at low idle and swing the upper structure
90 ° to bring the work equipment to the side of the track.
3.
Push up the machine until the track is raised slightly from the ground. Perform idle rotation of track for 2
minutes. Repeat this procedure on both the right and left sides.
REMARK
When rotating the track at idle, rotate equally both forward
and in reverse.
METHOD FOR BLEEDING AIR FROM ATTACHMENT (WHEN ATTACHMENT IS
EQUIPPED)
NOTICE
• If the method of air bleeding from the attachment is specified by the manufacturer, bleed the air ac-
cording to the specified procedure.
• After completing the air bleeding operation, stop the engine, and leave the machine for 5 minutes
before starting operations. This will remove the air bubbles in the oil inside the hydraulic tank.
MAINTENANCE PROCEDURE
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