Large Abnormal Sound Is Made When Upper Structure Stops Swinging - Komatsu Galeo PC800-8 Shop Manual

SEN00794-02
H-27 Large abnormal sound is made when upper structure stops swinging
Failure • Large abnormal sound is made when upper
phenomenon structure stops swinging
Relative
information
Malfunction of back
1 pressure compensation
valve
Possible causes
and standard
Wrong adjustment or mal-
value in normal
2 function of swing motor
state
(safety valve)
Swing machinery
3
defective internally
Failure • Large abnormal sound is made when upper
phenomenon structure stops swinging
Relative
information
Malfunction of swing
1 control valve
Possible causes
and standard (suction valve)
value in normal
state
Malfunction of swing motor
2
(suction valve)
38
Cause Standard value in normalcy and references for troubleshooting
The back pressure compensation valve may malfunction. Check it
directly.
aKeep the engine stopped for the preparations, and run it at high idle
during troubleshooting.
Left work equipment control lever
Swing relief (in either direction)
If the oil pressure is still abnormal after adjustment, the safety valve may
malfunction. Check the safety valve directly.
Swing machinery may have a defect in it. Check it directly. (The swing
machinery can be checked by abnormal sound, abnormal heating, metal
dust in the drained oil, etc.)
Cause Standard value in normalcy and references for troubleshooting
The suction valve of the swing control valve may malfunction. Check it
directly.
(The suction valves of the right and left swing control valves can be
checked by exchanging them with each other and seeing the change of
the phenomenon.)
The suction valve of the swing motor may malfunction. Check it directly.
(The suction valves of the right and left swing motors can be checked by
exchanging them with each other and seeing the change of the phe-
nomenon.)
(1) Large abnormal sound is made when the upper
structure stops swinging in both directions.
(2) Large abnormal sound is made when the upper
structure stops swinging in only 1 direction.
40 Troubleshooting
Swing relief pressure
+2.5
28.9 MPa
–0.5
+25
2
{295 kg/cm }
–5
PC800, 850-8