Skyjack SJKB-40-D Operating Maintenance Instructions & Part List page 81

TROUBLE
NO PLATFORM ROTATE
RIGHT
NO PLATFORM ROTATE
RIGHT OR LEFT
NO TELESCOPE RE-
TRACT
NO TELESCOPE EX-
TEND
TELESCOPE CYLINDER
DRIFTS IN
NO RISER BOOM DOWN
NO RISER BOOM UP
RISER BOOM DRIFTS
DOWN
NO PLATFORM LEVEL-
ING DOWN
SECTION 4, Page 30
TROUBLESHOOTING (Cont.)
PROBABLE CAUSE
HYDRAULIC SYSTEM (Cont.)
1. Stuck or defective platform rotate
right valve 4H-37A.
2. Defective platform rotary actuator
RA1
3. Stuck counter balance valve CB5.
1. Plugged orifice 04.
2. Defective platform rotary actuator
RA1.
1. Stuck or defective telescope retract
valve 4H-38A.
2. Stuck counter balance valve CB4.
1. Stuck or defective telescope
extend valve 4H-39A.
2. Stuck counter balance valve CB3.
1. Leaking or defective counter
balance valve CB4.
2. Telescope cylinder C3 by passing
internally.
1. Stuck or defective riser boom
down valve 4H-13A.
2. Stuck counter balance valve CB2.
1. Stuck or defective riser boom up
valve 4H-14A.
1. Leaking or defective counter
balance valve CB2.
2. Riser cylinder C1 by passing
internally.
1. Stuck or defective platform level
down valve 4H-40A.
2. Stuck counter balance valve CB1.
3. Leveling master cylinder by
passing internally.
4. Stuck counter balance valve
CB12.
JUN. 1999
REMEDY
1. Clean Valve.
defective.
2. Check Actuator. Replace if
defective.
3. Clean Valve.
defective.
1. Clean Orifice.
2. Check Actuator. Replace if
defective.
1. Clean Valve.
defective.
2, Clean Valve.
defective.
1. Clean Valve.
defective.
2, Clean Valve.
defective.
1. Check Valve.
defective.
2. Rebuild Cylinder. Replace if
damaged.
1. Clean Valve.
defective.
2, Clean Valve.
defective.
1. Clean Valve.
defective.
1. Check Valve.
defective.
2. Rebuild Cylinder. Replace if
damaged.
1. Clean Valve.
defective.
2. Clean Valve.
defective.
3. Rebuild cylinder. Replace if
damaged.
4. Clean Valve.
defective.
SJKB-40-D, SJKB-40-D/F
Replace if
Replace if
Replace if
Replace if
Replace if
Replace if
Replace if
Replace if
Replace if
Replace if
Replace if
Replace if
Replace if
Replace if