MHP Operating & Maintenance Manual
21
MAINTENANCE
MHP HYDRAULIC SCHEMATIC
MAIN SPOOL
ADJUSTMENT
SCREW
PILOT VALVE
ADJUSTMENT
SCREW
SPEED VALVE ADJUSTMENT POINTS
Figure 26
HYDRAULIC MAINTENANCE
Speed Valve
The speed valve allows the jaws to shift into high
speed while closing. There are two screws you can
use to control this speed change, the Main Spool
Adjustment Screw and the Pilot Valve Adjustment
Screw.
Testing the Speed Valve
Close the jaws and observe the movement. If the
speed valve is working properly, the jaw closing speed
will increase after 1-2 inches of movement.
Adjusting the Speed Valve
• If the jaw movement doesn’t shift to high speed
when closing, adjust the pilot valve adjustment
screw clockwise until the jaws shift speed.