Hydraulic Drift Of Work Equipment Is Large - Komatsu Galeo PC138US-8 Shop Manual

SEN02468-01
H-10 Hydraulic drift of work equipment is large
Trouble

• Hydraulic drift of work equipment is large.

Related
• Conduct the troubleshooting in working mode P.
information
1 Boom cylinder defective
Possible causes
and standard
value in normal
Defective sealing of boom
state
2
control valve (lock valve)
Defective sealing of central-
3
ized safety-suction valve
Trouble • Hydraulic drift of work equipment is large.
Related
• Conduct the troubleshooting in working mode P.
information
1 Arm cylinder defective
Possible causes
and standard
Defective sealing of arm con-
value in normal
2
trol valve (spool)
state
Defective sealing of arm con-
3
trol valve (suction valve)
Defective sealing of central-
4
ized safety-suction valve
Trouble • Hydraulic drift of work equipment is large.
Related
• Conduct the troubleshooting in working mode P.
information
1 Bucket cylinder defective
Possible causes
and standard
Defective sealing of bucket
value in normal
2
control valve (spool)
state
Defective sealing of bucket
3
control valve (suction valve)
Defective sealing of central-
4
ized safety-suction valve
14
Cause Standard value in normal state/Remarks on troubleshooting
a
Relieved in RAISE direction
Sealing of the lock valve of the boom control valve may be defec-
tive. Check it directly.
Sealing of the centralized safety-suction valve of the control valve
may be defective. Check it directly.
Cause Standard value in normal state/Remarks on troubleshooting
a
Sealing of the spool of the arm control valve may be defective.
Check it directly.
Sealing of the suction valve of the arm control valve (on the bottom
side) may be defective. Check it directly.
Sealing of the centralized safety-suction valve of the control valve
may be defective. Check it directly.
Cause Standard value in normal state/Remarks on troubleshooting
a
Relieved in CURL direction
Sealing of the spool of the bucket control valve may be defective.
Check it directly.
Sealing of the suction valve of the bucket control valve (on the bot-
tom side) may be defective. Check it directly.
Sealing of the centralized safety-suction valve of the control valve
may be defective. Check it directly.
(1) Hydraulic drift of boom is large.
Keep the engine stopped for the preparations, and keep it
running at high idle during the troubleshooting.
Boom cylinder
(2) Hydraulic drift of arm is large.
Keep the engine stopped for the preparations, and keep it
running at high idle during the troubleshooting.
Arm cylinder
Relieved in IN direction
(3) Hydraulic drift of bucket is large.
Keep the engine stopped for the preparations, and keep it
running at high idle during the troubleshooting.
Bucket cylinder
40 Troubleshooting
Leakage from cylinder
15 cc/min
Leakage from cylinder
15 cc/min
Leakage from cylinder
15 cc/min
PC138US, USLC-8
1