Komatsu Galeo PC800-8 User Manual

PC800, 850-8 19
40 Troubleshooting SEN00794-02
H-11 Hydraulic drift of work equipment is large
Failure
phenomenon
• Hydraulic drift of work equipment is large (1) Hydraulic drift of boom is large
Relative
information
Possible causes
and standard
value in normal
state
Cause Standard value in normalcy and references for troubleshooting
1
Defective seal of boom
control valve (spool)
Since the spool of the boom control valve (Lo) may have a malfunction,
check it directly.
2
Malfunction of boom con-
trol valve (safety & suction
valve)
Since the safety & suction valve (bottom side) of the boom control valve
(Lo) may have a malfunction, check it directly. (The safety & suction
valve may be checked by replacing it with one of another work equip-
ment circuit. After checking, however, be sure to return the safety & suc-
tion valve since its set pressure and structure are different from the
others.)
3
Defective seal of boom cyl-
inder
aPrepare with the engine stopped, then carry out troubleshooting with
the engine at high idle.
R.H. work equipment control lever Leakage from cylinder
Relieved in boom RAISE position Max. 20 cc/min
Failure
phenomenon
• Hydraulic drift of work equipment is large (2) Hydraulic drift of arm is large
Relative
information
Possible causes
and standard
value in normal
state
Cause Standard value in normalcy and references for troubleshooting
1
Defective seal of arm con-
trol valve (spool)
Since the spool of the arm control valve (Lo) may have a malfunction,
check it directly.
2
Malfunction of arm
control valve
(safety & suction valve)
Since the safety & suction valve (head side) of the arm control valve
(Lo) may have a malfunction, check it directly. (The safety & suction
valve may be checked by replacing it with one of another work equip-
ment circuit. After checking, however, be sure to return the safety & suc-
tion valve since its set pressure and structure are different from the
others.)
3
Defective seal of arm
cylinder
aPrepare with the engine stopped, then carry out troubleshooting with
the engine at high idle.
L.H. work equipment control lever Leakage from cylinder
Relieved in arm IN position Max. 20 cc/min

Komatsu Galeo PC800-8 Specifications

General

Brand	Komatsu
Model	Galeo PC800-8
Category	Excavators
Language	English