Komatsu PC130-7, Руководство по ремонту

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PC130-7
20-521
TROUBLESHOOTING
H-22 Upper structure does not swing
Trouble (1) Upper structure does not swing in either direction.
Related
information
• Carry out the troubleshooting in working mode A.
Possible causes
and standard
value in normal
state
Cause Standard value in normal state/Remarks on troubleshooting
1
Malfunction of swing hold-
ing brake solenoid valve
a
Prepare with engine stopped, then run engine at high idling and carry
out troubleshooting.
Right work equipment control lever Solenoid valve output pressure
Neutral position
0 MPa
{0 kg/cm
2
}
SWING position
2.84 – 3.43 MPa
{29 – 35 kg/cm
2
}
2
Malfunction of swing motor
(parking brake) The parking brake of the swing motor may have a malfunction. Check it
directly.
3
Malfunction of swing motor
(safety valve)
a
Prepare with engine stopped, then run engine at high idling and carry
out troubleshooting.
Swing lock switch
Left work equipment
control lever
Swing relief pressure
LOCK
Relieved in SWING
position
28.9 – 32.9 MPa
{295 – 335 kg/cm
2
}
4
Defective swing motor
(motor unit)
a
Prepare with engine stopped, then run engine at high idling and carry
out troubleshooting.
Swing lock switch
Left work equipment
control lever
Swing relief pressure
LOCK
Relieved in SWING
position
Max. 6
l
/min
5 Defective swing machinery
The swing machinery may have a defect in it. Check it directly. (It may
be checked by abnormal sound, abnormal heating, metal chips in drain
oil, etc.)
Trouble (2) Upper structure swings only in 1 direction.
Related
information
• Carry out the troubleshooting in working mode A.
Possible causes
and standard
value in normal
state
Cause Standard value in normal state/Remarks on troubleshooting
1
Malfunction of swing PPC
valve
a
Prepare with engine stopped, then run engine at high idling and carry
out troubleshooting.
Right work equipment control lever PPC valve output pressure
Neutral position
0 MPa
{0 kg/cm
2
}
SWING position
2.84 – 3.43 MPa
{29 – 35 kg/cm
2
}
2
Malfunction of swing con-
trol valve (spool) The spool of the swing control valve may have a malfunction. Check it
directly.
3
Defective seal of swing
motor (suction valve) The seal of the suction valve of the swing motor may be defective.
Check it directly.
H-22
(1)