PETTIBONE 8044 - Main Directional Valve Troubleshooting

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Pettibone Michigan, L.L.C. OWNER/OPERATOR MANUAL MODEL 6036/6044/8036/8044
Oil leaks at either end of
spool
Oil leaks between
sections
Spool does not return to
neutral position
Solenoid for fork frame
side tilt fails to energize
No motion, slow or jerky
action of hydraulic system
Defective O-ring(s) in spool
control.
Pinched or blown seal(s).
Tie rod fasteners not cor-
rectly torqued.
Broken centering spring(s)
in spool control.
Bent spool.
Foreign particles in valve.
Defective fuse, switch or
solenoid.
Defective electrical wire
from switch to solenoid.
Electrical plug disconnected
from solenoid.
Low oil level in reservoir.
Plugged sump strainer.
Valve body cracked inside.
Spool not moved to full
stroke.
Replace O-ring(s).
Replace seal(s).
Torque fasteners to 44 ft.
lbs.
(60 Nm).
Replace spring(s).
Replace section.
Clean valve.
Ensure that 12 vdc is
available to solenoid coil. If
no voltage available, replace
fuse or switch. If voltage is
available, replace solenoid.
Repair wiring defects or
replace wiring.
Connect plug to solenoid.
Add oil to FULL mark on
filler cap/dipstick.
Clean strainer.
Replace valve section.
Check spool travel.
SYMPTOM PROBABLE CAUSE REMEDY
MAIN DIRECTIONAL VALVE TROUBLESHOOTING