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MA8:7
V Range 502
l
652
l
802 Maintenance Manual
Johnston Sweepers Limited
Chapter - Fault Diagnosis
Maxigap Nozzle
Fault Symptom
Possible Cause
Maxigap will not tilt
1.
Check feed to pneumatic solenoid/Plug LED V1 or V9 if a
dual.
2.
Pneumatic
solenoid
valve
faulty.
3.
Cylinder
pivot/linkage
seized.
Channel Brush
Fault Symptom
Possible Cause
Rotating slowly
1.
Motor worn.
2.
Hydraulic
pump
worn.
4.
Channel
brush
worn.
3.
Check hydraulic pressure to aid fault diagnosis.
Works intermittently
1.
Check switch in Control Panel and looms for loose
connections.
Brush fails to lift
1.
Check for electrical power at solenoid/Plug LED V5 or V6 if
a dual.
2.
Check pneumatic solenoid for correct operation.
3.
Seals
in
cylinder
leaking.
Summary of Contents for VM502
Page 2: ...V Range 502 l 652 l 802 Maintenance Manual...
Page 20: ...V Range 502 l 652 l 802 Maintenance Manual MA1 18 Chapter Scheduled Maintenance...
Page 36: ...V Range 502 l 652 l 802 Maintenance Manual MA2 16 Chapter Hydraulic System...
Page 162: ...V Range 502 l 652 l 802 Maintenance Manual MA5 26 Chapter Pneumatic System...
Page 170: ...V Range 502 l 652 l 802 Maintenance Manual MA6 8 Chapter Wearing Items...
Page 188: ...V Range 502 l 652 l 802 Maintenance Manual MA7 18 Chapter Remove and Refit Procedures...
Page 204: ...V Range 502 l 652 l 802 Maintenance Manual MA8 16 Chapter Fault Diagnosis...
Page 212: ...V Range 502 l 652 l 802 Maintenance Manual MA9 8 Chapter Service Tools...
Page 220: ...V Range 502 l 652 l 802 Maintenance Manual MA10 8 Chapter Health and Safety...