Poweramp POWERHOOK P4111-0010 5.2006 - Manual (Page 46)

44 4111-0010 — December 2004
TROUBLESHOOTING POWERHOOK
Symptom Possible Cause Solution
Lowered restraint
returns to fully retracted
position but unit does
not automatically shut
OFF.
Pump Operates in
pressure relief.
Restraint remains
lowered. Proximity switch on rear of
(closest to rear pit wall)
guide track that senses
when restraint fully retracted
out of adjustment. Locate switch on rear of guide track. Observe
indicator light at controller input (#6) that receives
signal from switch. Input light should turn OFF when
restraint fully extended. If this does not occur:
-Check switch position, loosen two guide track
mounting bolts, tap guide track assembly back
towards rear pit wall.
-Switch should be positioned approximately 1/4”
from the inside wall of the track. Make sure that the
switch face does not extend further than the guide
track mounting bars welded to the cylinder. Position
switch so that face will not come into contact with
guide rod.
-Tighten nuts to secure switch. NO NOT overtighten
nuts. Maximum tightening torque is 25 lb/ft.
-Run restraint. Make sure motor shuts off when
hook is in stored position. If motor does not shut off,
reposition guide track slightly forward of current
position.
Restraint fully retracted
but does not raise, even
when ON-OFF switch
turned OFF. Solenoid “D” valve stuck
ON. Locate solenoid (See Parts: Valve Block).
Remove coil from cartridge valve and cartridge valve
from valve block.
-Check valve for contaminant's and/or damage.
-Replace valve if damaged.
Carefully wipe valve with clean rag (do not damage
“O” rings on valve.
-Check valve block for contaminant's.
-Replace valve and coil.
NOTE: Do not overtighten valve into block. Max Torque:
30-40 lb/ft. or snug to prevent leakage. Tighten coil snug,
avoid overtightening and causing valve to bind.
Operate unit. Replace valve if problem persists and
all other troubleshooting procedures performed.
Binding inside positioning
cylinder. Locate positioning cylinder. Place pan under hose
connected to cylinder to catch fluid.
SLOWLY loosen hose since fluid may exit cylinder
rapidly (cylinder is spring loaded with spring
compressed when lowered). A cylinder that is not
binding will raise as fluid leaves the cylinder. A
cylinder that is binding will remain lowered, even
when the hose is completely removed from the
cylinder.
Replace a cylinder that is binding.