Page 91
Pettibone Michigan, L.L.C. OWNER/OPERATOR MANUAL MODEL 6036/6044/8036/8044
Cylinder will not
operate when joystick is
actuated
Cylinder drifts (will not
remain in position)
Failed hose or hose connec-
tions leaking.
Low oil level in reservoir.
Plugged sump strainer.
Insufficient pilot pressure
supplied to main valve.
Oil bypassing spool in main
valve.
Rod wiper leaking exces-
sively.
Oil bypassing cylinder
piston.
Faulty pump operation.
Load larger than capacity.
Oil bypassing spool in main
valve.
Oil bypassing cylinder
piston.
Oil bypassing counterbal-
ance valve cartridge.
Spool not centered in main
valve.
Main relief valve not hold-
ing.
Load larger than capacity.
Replace hose or tighten
loose connections.
Add oil to FULL mark on
reservoir dipstick.
Clean strainer.
Check pilot pressure with a
600 psi pressure gauge.
Correct pressure should be
500(±25) psi.
Replace defective spool
seal (s).
Replace defective wiper.
Replace defective piston
seal.
Repair or replace pump.
Reduce to rated load capac-
ity at rated load center.
Replace defective spool
seal(s).
Replace defective piston
seal.
Replace defective cartridge
seal (s).
Replace spool centering
springs.
Clean cartridge or replace.
Reduce to rated load capac-
ity at rated load center.
SYMPTOM PROBABLE CAUSE REMEDY
EXTENSION CYLINDER TROUBLESHOOTING
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