Pub. 1147 - Rev. 7 SEPTEMBER 2004
41
Mechanical Dock Leveler Hydraulic Conversion
Problem
Probable Cause
Remedy
4. Lip extends slowly and/or does not
c. Hydraulic fluid level is low.
c.Check oil level in tank.
fully extend. -Continued
Refill if there is less than 3-1/2" of oil
in the tank when the unit is held open
with the SAFE-T-STRUT™. Do not
exceed maximum oil level indicated by
the “Oil Level” decal on the reservoir
(approximately 3-1/2" depth)
d. System leak.
d. Check hoses, fittings, valves and
power unit for leaks.
e. Adjustable sequence valve pressure.
e. Readjust the sequence valve.
has been set too high.
f. Adjustable system relief valve pressure
f. Readjust until the relief pressure is
is set too low
1200 psi.
g. Debris in the hydraulic system.
g. Drain the oil from the power unit,
hoses and cylinders and replace with
fresh oil.Verify that the suction filter in
the tank is not clogged.
h. ARTD actuator failure
h. Verify that the ARTD actuator is
functioning properly.
i. Lip cylinder failure.
i. Replace lip cylinder.
5. Lip remains fully or partially extended.
a. Debris on lip hinge.
a. Remove dirt, debris and corrosion
from the lip hinge spools.
b. Lack of lubrication.
b. Without grease fittings – Lubricate the
hinge spools with SAE30 oil.
With grease fittings – Lubricate the
hinge spools with moly based grease.
c. Debris in the hydraulic system.
c. Consult factory.
d. Valve failures on power unit endhead.
d. Inspect, test and replace the pilot to
close check valve if necessary.
Inspect, test and replace the pilot to
open check valve if necessary.
Inspect, test and replace the
adjustable sequence valve if
necessary.
Inspect, test and replace the orifice
plugs if necessary.
e. ARTD actuator failure.
e.Verify that the ARTD actuator is
functioning properly.
f. Lip cylinder failure.
f. Replace lip cylinder.
W h e n c h e c k i n g f o r a h y d r a u l i c s y s t e m
l e a k , f i r s t l o o k f o r t h e w e t h o s e s o r
f i t t i n g s w i t h o u t t h e p o w e r u n i t
r u n n i n g . O n c e t h e s u s p e c t e d l e a k h a s
b e e n l o c a t e d , h a v e a n a s s i s t a n t
p o w e r - u p t h e p u m p . M O V E A P I E C E O F
C A R D B O A R D A R O U N D T H E
SUSPECTED LEAK TO LOCATE THE
FAULTY PART. DO NOT USE YOUR
HAND. MAKE SURE TO KEEP HANDS,
ARMS AND FACE AWAY FROM THE
AREA OF THE SUSPECTED LEAK.
H i g h p r e s s u r e h y d r a u l i c f l u i d c a n b e a n
i n v i s i b l e s p r a y t h a t w i l l p e n e t r a t e f l e s h .
WARNING
