34
Pub. 1147 - Rev. 7 SEPTEMBER 2004
Mechanical Dock Leveler Hydraulic Conversion
SHUTTLE VALUE ADJUSTMENT
(CONTROLS LEVELER DESCENT)
NOTE
When making adjustments in extremely cold
temperatures (below freezing 32
0
F), run unit
several times (5 to 10 cycles) to confirm that
the velocity fuse does not lock-up with warmer
oil.
•
Do not operate leveler with anyone
standing on or in front of the lip.
•
Never go under the hydraulic leveler
platform or lip without engaging and
securing the SAFE-T-STRUT
®
.
•
Make sure that the leveler power is
locked out and tagged out according to
OSHA regulations and approval local
codes
•
Shuttle valve is factory sealed.
Adjustments to be completed by trained
technician only.
Valve Position Illustrated Represents
The Nominal Factory Setting Of 3-1/2 Turns
Out From The Fully Turned In Position
0.17"
O-Rings
Locknut
Cap
Adjustment
Screw
Shuttle
Valve
Body
Locknut
Seal
O-Rings
Cap
Sequence
Valve
Adjustment
Screw
Viewed From
Tank End
System
Relief Valve
1. Leveler must be adjusted to lower, from full raised
position with lip extended to the header stops, in 13
to 17 seconds.
2. Remove protective cap and O-ring. Loosen locknut;
without turning valve body or adjustment screw. Turn
adjustment screw to vary platform lowering speed.
See Figures 35 and 36.
3. Adjustments should be no more than 1/8 turn
increments.
4. Loosen adjustment screw to decrease platform
speed while lowering (excessive loosening can
eliminate platform lowering).
5. Tighten adjustment screw to increase platform speed
while lowering (velocity fuse may lock-up as a result
of increased platform speeds while lowering).
6. Tighten locknut without turning valve body or
adjustment screw.
7. Reinstall o-ring and protective cap and tighten cap.
8. Re-test the unit several times to verify the setting.
FIGURE 36 - VALUE ADJUSTMENTS
FIGURE 35 - VALUE NOMINAL SETTING
DANGER
WARNING
