Blue Giant BG ZERO, Owner'S Manual, Page: 16 / 100

Table 3-1 Troubleshooting Chart - Continued
MALFUNCTION PROBABLE CAUSE CORRECTIVE ACTION
TROUBLE WITH LIFTING OR
LOWERING
• Oil sprays or flows from the top
of the lift cylinder.
Defective packing in lift cylinder Repair lift cylinder.
• Squealing sounds when lifting
Operator’s platform.
Identify oil leak and fill reservoir.
Apply grease. a. Oil level too low.
b. Dry channels in mast.
c. Defective mast or Platform
rollers
Replace rollers.
• Platform does not lift to full lift
height.
a. Oil level too low. Add oil to reservoir.
b. Load larger than capacity. Refer to I.D.plate for capacity.
• Weak, slow or uneven action of
hydraulic system.
a. Defective pump or relief valve. Check pressure. Adjust as
necessary.
b. Worn lift cylinder. Replace cylinder.
c. Load larger than capacity. Refer to I.D.platefor capacity.
d. Defective lift motor relay. Replace relay on pump motor.
e. Battery charge low. Charge battery.
• Platform does not lift, pump
motor does not run.
a. Battery is dead or discon-
nected.
Check and recharge if required.
b. Defective wiring. Check and repair as required.
c. Defect in electrical system for
operating pump motor.
Check lift switch on platform, as
well as the relay.
• Platform does not lift, motor
runs.
Defect in hydraulic system. Check the oil level in the reservoir
and the oil lines to the lift
cylinder, and repair as required.
If normal, check the hydraulic
pump, and relief valve. Repair, or
adjust.
• Platform lifts, but will not go
down.
Defect in hydraulic system Check lowering control switch and
lowering solenoid. Replace as
required.
• Load will not hold a. Oil bypassing internally in
control valve
b. Worn lift cylinder or packing.
• Platform does not lift to top.
Pump motor runs.
• Forks drifts down under load
when in a raised position.
a. Oil level too low.
b. Load larger than capacity.
c. Batteries need charging. Leak
in hydraulic system, lift
cylinder or lowering valve.
Replace valve assembly.
Repack cylinder.
Add oil to reservoir.
Refer to nameplate on side of
mast for maximum load capacity.
Charge batteries.
Check for leaking fitting in
hydraulic line and repair as
required. Repack lift cylinder
or replace valve assembly.
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