Upper Structure Does Not Swing - Komatsu Galeo PC800-8 Shop Manual

SEN00794-02
H-22 Upper structure does not swing
Failure

• Upper structure does not swing

phenomenon
• Check that the other work equipment and travel are normal. (If either of them is abnormal, carry out
Relative troubleshooting related to it.)
information • When carrying out the following troubleshooting, set the swing lock switch in OFF and the working
mode in the P-mode.
Malfunction of swing hold-
1
ing brake solenoid valve
Malfunction of swing motor
2
(parking brake)
Possible causes
and standard
value in normal
state
Wrong adjustment or mal-
3 function of swing motor
(safety valve)
Swing motor (motor unit)
4
defective internally
Swing machinery
5
defective internally
30
Cause Standard value in normalcy and references for troubleshooting
aKeep the engine stopped for the preparations, and run it at high idle
during troubleshooting.
Left work equipment control lever
Neutral (After 10 seconds or more)
The parking brake of the swing motor may malfunction. Check it directly.
aKeep the engine stopped for the preparations, and run it at high idle
during troubleshooting.
Left work equipment control lever
If the oil pressure is still abnormal after adjustment, the safety valve may
malfunction. Check the safety valve directly.
The motor unit of the swing motor may have a defect in it. Check it
directly.
Swing machinery may have a defect in it. Check it directly. (The swing
machinery can be checked by abnormal sound, abnormal heating, metal
dust in the drained oil, etc.)
(1) The upper structure swings in neither direction.
Operated to swing
(in either direction)
Swing relief
(in either direction)
40 Troubleshooting
Solenoid valve outlet pressure
2
0 MPa {0 kg/cm }
Min. 2.74 MPa
{Min.28 kg/cm 2 }
Swing relief pressure
+2.5
28.9 MPa
–0.5
+25
2
{295 kg/cm }
–5
PC800, 850-8