Vestil AHLT - Manual (Page 8)

8
HYDRAULIC EQUIPMENT
Trouble Shooting Quick Reference Guide
(For further information contact the factory)
****BEFORE PREFORMING ANY MAINTENANCE WORK ALWAYS INSTALL MAINTENANCE SAFETY BLOCKS****
Observation Possible Cause Remedy
1.) Table does not raise but pump is running
2.) Table raises too slowly.
3.) Motor labors, or is excessively hot.
4.) "Spongy" or "Jerky" table operation. Do not
confuse spongy operation with small surges caused by
foreign material on table wheel roller plate.
5.) Table lowers too slowly when loaded.
a. Hose or hydraulic line is leaking.
b. Fluid level in reservoir is low.
c. Load exceeds capacity requirements. Relief Valve is
bypassing the fluid back into the reservoir.
d. Suction filter is clogged, starving pump.
e. Suction line may be leaking air, due to loose fittings.
f. Filler/Breather cap on tank may be clogged.
g. Lowering Valve may be energized by faulty wiring or
stuck open.
h. Hydraulic pump may be inoperative.
a. Foreign material stuck in lowering solenoid, causing
some fluid to bypass back into tank.
b. Foreign material clogging suction filter, breather cap,
or a pinched hose.
d. Table overloaded.
e. Pump is inoperative.
a. Oil starvation causes pump to bind. High internal
heat is developed. If this occurs, pump may be
permanently damaged.
b. Binding cylinders.
a. Fluid starvation.
b. Air in system.
a. Down Valve filter clogged.
b. Pinched tube or hose.
c. Foreign material in flow control valve.
d. Binding cylinders
e. Foreign material in velocity fuse.
c. Correct as necessary.
d. Add fluid. Refer to Owner's Manual for proper fluid
levels.
e. DO NOT CHANGE RELIEF VALVE SETTING.
Instead, reduce the load to rated capacity.
f. Remove and clean.
g. Inspect all fittings for proper fit.
h. Remove and clean.
i. Remove solenoid valve. Check and clean. (Refer to
Hydraulic Section of Owner's Manual).
j. Disconnect hydraulic line at power unit. Put pressure
line in a large container and cycle pump. If no output,
check the pump motor coupline, which may be
defective, and correct as necessary. If pump is worn,
consult factory for replacement parts service.
a. Lower the platform. Remove the solenoid valve and
clean. (Refer to Hydraulic Section of Owner's Manual).
b. Correct as necessary. (See also, 1(f), (h).
d. See 1(e).
e. See 1(j).
a. See 1(d), (f), (g), (h), (j).
b. Align cylinders correctly.
a. See 1(d), (f), (g), (j).
b. See air bleed procedure p.9.
a. Remove solenoid valve and clean filter.
b. Correct as necessary. (In case of pipe, check for
obstruction in line.)
c. Remove and clean Flow Control Valve. (Refer to
Hydraulic Section of Owner's Manual).
d. Align cylinders correctly.
e. Remove and clean velocity fuse. (Refer to Hydraulic
Section of Owner's Manual.)