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ATTENTION: After this last operation is completed, the oil level position in the
hydraulic oil tank should be slightly raised.
Replace the hydraulic oil return filter element
First replacement after 2000 hours of work, and every 2000 hours thereafter.
1)
Fully extended the piston rod of each hydraulic cylinder, and then stop the engine.
2)
Take off the oil tank screw plug to make it depressurized.
3)
Unscrew the filter element 6, replace the new filter element (seal the gasket to oil
before installation).
4)
Start the engine and operate the working device.
5)
Check the hydraulic oil level and refill it if necessary.
6)
Retighten the screw plug and close the sight hole cover.
7)
To pressurize the hydraulic tank, retract the piston rod of the hydraulic cylinder.
5.14.4.
Vent air from the hydraulic system
A)
Vent air from the pump
1)
Loosen the air vent plug installed in the drain port and check for oil flow. The
air venting is completed.
2)
Tighten the screw plug after venting is completed.
ATTENTION: If the pump is not filled with oil when the pump is running, it
will cause abnormal high temperature and damage the pump.
B)
Vent air between the pump and the hydraulic oil tank
1)
Start the engine and keep it running at low to medium speed.
2)
Operate the work device slowly for about 5 minutes to vent air.
ATTENTION: If the engine is allowed to run at high speed without expelling
the air between the pump and the tank, the pump will also be abnormally hot,
which could damage the pump.