Poweramp POWERHOOK P4111-0010 5.2006 - Manual (Page 48)

46 4111-0010 — December 2004
TROUBLESHOOTING DOCK LEVELER
Symptom Possible Cause Solution
Platform does not rise to
full height. Low hydraulic fluid. Add fluid, see Maintenance section for proper fluid
level and type.
Platform DOES rise to
full height, but lip DOES
NOT extend or extend
fully. Low hydraulic fluid. Add fluid, see Maintenance section for proper fluid
level and type.
Logic block (valve) lever
cable weight too low on
cable. Adjust cable weight. See Adjust Cable Weight and
Down Speed Control in the Adjustment section.
Lip does not extend. Logic block spool valve
stuck in the up position or
valve lever binding so that
the lever will not push the
spool down. Apply penetrating oil to spool area and valve lever
pivot at top of logic block.
If necessary, disconnect the valve lever from logic
block. Move spool valve up and down until spool
valve slides freely. If the spool valve cannot be made
to slide freely, replace spool valve.
Lubricate valve lever pivot with white lithium grease.
Lip extends almost
immediately when the
RAISE button is pushed.
Platform rises after lip is
fully extended. Logic block spool valve
stuck in the down position
or valve lever binding
causing lever to prematurely
push the spool down. Apply penetrating oil to spool area and valve lever
pivot at top of logic block.
If necessary, disconnect the valve lever from logic
block. Move spool valve up and down until spool
valve slides freely. If the spool valve cannot be made
to slide freely, replace spool valve.
Lubricate valve lever pivot with white lithium grease.
Platform locks into
“safety” as platform
lowers. Lip drops to
vertical position. Platform lowering speed is
too fast. Adjust platform down speed control.
See Adjust Cable Weight and Down Speed Control
in the Adjustment section.
NOTE: Extreme cold weather OR incorrect fluid
may cause platform to lock. Adjustment is same.
Dock leveler equipped
with ARTD: Platform
does not automatically
return to the
cross-traffic position or
operates abnormally. The auto return proximity
switch not sensing target
correctly. Adjust proximity switch and target as necessary. See
Adjust Auto Return To Dock (ARTD) in the
Adjustment section.
Defective proximity switch. Replace switch.
Broken wire. Loose or
corroded wire connections. Repair or replace wires and connections as
necessary.