Parts List and Operating Instructions
Form No. 102947
TROUBLE-SHOOTING GUIDE
Repair procedures must be performed in a dirt-free environment by qualified personnel who are familiar with this
equipment.
Sheet No.
2 of 5
Rev. 2
Date: 28 Dec. 1998
TROUBLE
CAUSE
SOLUTION
Erratic Action
Jack does not advance
Jack only extends partially
Jack advances slowly
Jack advances but doesn’t hold
pressure
Jack leaks oil
Jack will not retract or retracts
slowly
1. Air in system
2. Viscosity of oil too high
3. Internal leakage in cylinder
4. Cylinder sticking or binding
1. Release valve is open
2. Low/no oil in reservoir
3. Air-locked system
4. Load is above capacity of system
1. Reservoir is low on oil
2. Piston rod is binding
1. Pump not working correctly
2. Leaking seals
1. Cylinder seals are leaking
2. Pump check valve not working
correctly
3. Overload valve leaking or not
adjusted correctly
1. Worn or damaged seals
1. Release valve is closed
2. Cylinder damaged internally
3. Reservoir too full
1. With jack sitting on its base and
ram retracted, bleed air by
opening release valve. Pump for
10 seconds.
2. Change to lower viscosity oil.
3. Replace worn seals. Check for
excessive contamination or wear.
4. Check for dirt, gummy deposits,
or leaks. Check for misalign-
ment, worn parts, or defective
seals.
1. Close release valve
2. Fill with oil and bleed system
3. Bleed the system
4. Use correct equipment
1. Fill reservoir
2. Check for dirt, gummy deposits,
or leaks. Check for misalign-
ment, worn parts, or defective
seals.
1. Rework pump
2. Replace seals
1. Replace seals
2. Clean/replace check valve
3. Replace/adjust overload valve
1. Replace seals
1. Open release valve
2. Send jack to authorized service
center for repair
3. Drain oil to correct level
