H-31 Shock Is Large When Upper Structure Stops Swinging - Komatsu PC88MR-10 Shop Manual

H-31 Shock is large when upper structure stops swinging

Shock is large when upper structure stops swinging.
Failure
Related
Perform all troubleshooting with working mode set in power (P) mode.
information
No. Cause
Malfunction of swing
1
PPC valve
Malfunction of slow
return valve for right
2
swing PPC
Malfunction of slow
return valve for left
3
swing PPC
Malfunction of swing
motor (reverse
4
prevention valve)
PC88MR-10
Troubleshooting of hydraulic and mechanical system (H-
Procedure, measuring location, criteria, and remarks
a Be ready with engine stopped, then perform troubleshooting with engine at
high idle.
Swing control
PPC valve output
pressure
Swing control
Slow return valve for right swing PPC may malfunction. Interchange slow
return valves for left and right swings, and check whether failure symptom
changes to make judgment.
Slow return valve for left swing PPC may malfunction. Interchange slow return
valves for left and right swings, and check whether failure symptom changes
to make judgment.
Reverse prevention valve of swing motor may malfunction.
Check for stuck spool and fatigue of spring.
At NEUTRAL
lever
Left swing and
Right swing
lever
40 Troubleshooting
mode)
(PC88MR-L49-400-A-Z0-A)
0 MPa {0 kg/cm 2 }
2.65 MPa
{27 kg/cm 2 }
40-509