Machine Does Not Swing - Komatsu ecot3 PC300LC-8 Shop Manual

SEN02633-03
H-23 Machine does not swing
Trouble (1) • Upper structure does not swing in either direction.
Related infor-
• Set the working mode in P-mode before start.
mation
Malfunction of swing holding
1
brake solenoid valve
Malfunction of swing motor
2
(holding brake section)
Possible causes
and standard
Defective adjustment or mal-
value in normal
3
state
4 Defective swing motor
5 Defective swing machinery
26
Cause
function of swing motor
(safety valve)
Standard value in normal state/Remarks on troubleshooting
a
Prepare with engine stopped, then run engine at high idle and
carry out troubleshooting.
Swing
Neutral
Operated
Holding brake section of swing motor may have malfunction. Check
it directly.
a
Prepare with engine stopped, then run engine at high idle and
carry out troubleshooting.
Swing lock switch
ON
If oil pressure does not become normal after adjustment, safety
valve may have malfunction or internal defect. Check safety valve
directly.
a
Prepare with engine stopped, then run engine at high idle and
carry out troubleshooting.
Swing lever
Swing relief
Swing machinery may have internal defect. Check it directly.
a
It may be checked by abnormal sound, abnormal heating,
metal chips in drain oil, etc.
40 Troubleshooting
Solenoid valve
0 MPa {0 kg/cm
2.84 – 3.43 MPa
{29 – 35 kg/cm
Swing lever Swing relief pressure
27.95 – 32.85 MPa
Swing relief
{285 – 335 kg/cm
Leakage from swing motor
Max. 11 l/min
PC300, 350-8
1
2
}
2
}
2
}