Lull 6K Service Manual - Manual (Page 259)

Boom and Transfer
Service Manual — Models 644B, 6K, 844C, 8K, 1044C, 10K 6-9
Fig. 6-6: Pilot Pressure Plug
c. (Ref. Fig. 6-6) If the pilot pressure is not within the recommended
range, adjust pressure as follows:
1). For models with control manifold hydraulics, remove the O-ring
plug from the pressure reducing cartridge with a 1/4" Allen
wrench. Use a 1/4" Allen wrench to adjust the reducing valve by
turning clockwise to increase pressure and counterclockwise to
decrease pressure.
Note: This pressure reducing cartridge is located in the port on the
control manifold marked PR.
2). For models with mid-inlet hydraulics, remove the O-ring plug
from the pressure reducing cartridge with a 5/16" Allen wrench.
Use a 1/4" Allen wrench to adjust the reducing valve by turning
clockwise to increase pressure and counterclockwise to
decrease pressure.
Note: This pressure reducing cartridge is located on the hydraulic pump.
3). Install O-ring plug and torque to 44–48 ft-lbs.
4). Retest pilot pressure, and make any additional valve
adjustments as required.
Hydraulic Cylinders
Description
All hydraulic cylinders used on JLG forklifts are a double-acting,
non-cushioned type with chromed rods.
The boom hoist, carriage tilt, boom extension, and frame tilt cylinders are
equipped with externally mounted counterbalance valves. These
counterbalance valves prevent movement of the cylinders in the event of
K
1134
O-ring
Plug
O-ring
Plug
Control Manifold Hydraulics Mid-Inlet Hydraulics
Pressure
Reducing
Valve
Pressure
Reducing
Valve