Komatsu PC200-8M0 Shop Manual page 913

500 Troubleshooting of hydraulic and mechanical system (H-mode)
H-22 Upper structure does not swing
Failure (2) Upper structure does not swing in only one direction.
Related infor-
q
Perform all troubleshooting with working mode in power mode (P).
mation
Malfunction of swing PPC
1
valve
Probable
causes and cri-
Malfunction of swing control
2
teria
valve (spool)
Malfunction of swing motor
3
(suction valve)
Malfunction of swing motor
4
(check valve)
PC200, 200LC, 220, 220LC-8M0
Cause
a Be ready with engine stopped, then troubleshoot with engine
high idle.
Left work equipment control
Spool of swing control valve may malfunction. Check the spool.
Suction valve of swing motor may malfunction. Check the valve.
* This failure can be checked by interchaning right and left suc-
tion valves of swing motor and watching how condition
changes.
Check valve of swing motor may malfunction. Check the valve.
* You may replace the check valves of the right and left motor-
swith each other and judge from the change of the phenome-
non.
Criteria and troubleshooting procedure
lever
Neutral
Left swing
Right swing
SEN06139-00
PPC valve output pressure
0 MPa
2
{0 kg/cm }
2.84 to 3.43 MPa
2
{29 to 35 kg/cm }
40-500
33