HELI CPD10, Operation & Service Manual

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of the pump’s surface increases to a over high degree, reduce the load and lower the oil
temperature. And then go on carrying on the trail.
e) Make the relieving pressure at 210kg/ cm
2
after the test and measure the flowl.
Measure the oil lever through the lifting speed.
5.2.3 Troubleshooting
Trouble Cause Trouble shooting
Insufficient
lifting
capacity or
unable to lift
1) Excessive wearing between the oil
pump
gear and pump body and
wider-than-normal gap.
2) Wearing and wider-than-normal gap of
the piston sealing part in the lifting
cylinder, excessive inner leakage.
3) Failure of safety valve spring of control
valve.
4) Excessive oil leakage due to wearing
between the control valve rod of control
valve and valve body.
5) Oil leakage among valve bodies of the
control valve .
6) Oil leakage in hydraulic pipe.
7) Higher-than-normal temperature of
hydraulic oil (should be ≤80
℃
), excessive
oil dilution and insufficient flow.
8) Excessive load.
1) Replace the wearable parts or oil
pump.
2) Replace with new piston sealing ring.
3) Replace with new spring.
4) Chromium plating the valve rod to
couple with the hole with the gap at
0.01
～
0.02.
5) Change the sealing ring, screw tight
the screw in sequence.
6) Check to see whether there is damage
to the sealing ring or connecting nut and
screw tight the pipe joint.
7) Replace the unqualified hydraulic oil,
stop operation to lower oil temperature
and try to find the cause of over high oil
temperature.
8) Lift load according to requirements.
Insufficient
pressure of
oil pump
1) Oil leakage due to wearing of ring seal
at fasteners.
2) Hydraulic oil is contaminated with air
to form foam, air leakage at oil suction
pipe-work, insuffi-
cient hydraulic oil.
3) Damaged ring seal inside the pump
cover groove.
4) Wearing of the end face of bearing
sleeve.
5) Oil pump gear wears.
6) Wrong rotation direction of oil pump. 1) Replace the ring seal.
2) Discharge air and add hydraulic oil.
3) Replace.
4) Replace.
5) Replace the oil pump.
6) Correct.
Trouble Cause Trouble shooting
Excessive self
tilting of the
tilting cylinder
1) Inner leakage of control valve.
2) Inner leakage due to the damaged
O-ring seal of piston rod of the tilting
cylinder.
3) Oil leakage due to the damaged
1) Replace O-ring seal, repair valve rod
and reassign the coupling gap between
valve rod and hole to 0.01
～
0.02.
2) Replace.
3) Replace.