Method For Bleeding Air From Hydraulic Circuit - Komatsu PC138US-11 Operation & Maintenance Manual

MAINTENANCE
The gas springs are installed inside the left console (1 place)
and at the cab ceiling window (2 places).
In the following cases, ask your Komatsu distributor for inspec-
tion, repair, and replacement.
• The lock lever cannot be pulled up lightly or the cab ceiling
window cannot be opened lightly.
• The lock lever dose not stay at LOCK position.
• The cab ceiling window does not stay open.
• Oil or gas is found to be leaking from the gas spring.

METHOD FOR BLEEDING AIR FROM HYDRAULIC CIRCUIT

When starting the engine, see "METHOD FOR STARTING ENGINE (3-153)". If necessary, see the paragraphs
for starting the engine, and moving/steering/stopping the machine in OPERATION section.
METHOD FOR BLEEDING AIR FROM PUMP
Perform it when any hydraulic component or oil has been replaced.
NOTICE
If the pump is operated without filling the pump case with hydraulic oil, abnormal heat will be generated
and this may cause a premature damage to the pump. Bleed air securely.
1.
Run the engine at low idle.
2.
Open the fuel filter cover on the right side of the machine.
3.
Loosen the air bleeder (1) installed to the pump and check
that oil oozes out from the air bleeder.
4.
After bleeding air, tighten air bleeder (1).
METHOD FOR BLEEDING AIR FROM PUMP AND HYDRAULIC TANK
Perform it when any hydraulic component or oil has been replaced.
NOTICE
If you run the engine at high speed without bleeding air from the piping between the pump and hydraul-
ic tank, the pump may heat abnormally and may be broken in a short period.
1.
Start and run the engine at medium speed (1650 rpm).
For starting the engine, see "METHOD FOR STARTING ENGINE (3-153)".
2.
Operate the work equipment slowly for approximately 5 minutes, and bleed air.
METHOD FOR BLEEDING AIR FROM CYLINDER
Perform it when any hydraulic component or oil has been replaced.
WENAM00111
MAINTENANCE PROCEDURE
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