Lull 944E-42 Service Manual - Manual (Page 325)

8.73 Model 644E-42/944E-42 Rev. 6/04
Hydraulic System
Not
OK
Not
OK
Check for external leaks,
loose fittings or lines
If park brake fails to release
with park brake gauge port
pressurized.
Tighten fittings or lines, or
replace fittings or lines
If OK
Not
OK
Within the front axle:
If not releasing, check the
piston seals.
If OK
NOTE:
When checking pressures in
circuits, refer to Section 8.7,
“Hydraulic System Testing,” for
correct pressure readings.
Recheck Port-a-Power device
for proper connection and
pressure setting.
Refer to ZF Axle Repair
Manual, Model MS-T 3045,
ZF part # 5871 550 002. JLG
part # 8990419 (644E Only)
or ZF Axle Repair Manual,
Model MS-T 3060, ZF part #
5871 560 002. JLG part #
8990430 (944E Only)
Before troubleshooting any
hydraulic circuit, ALWAYS
begin by checking the
following:
1. Hydraulic oil level in the
reservoir
2. All hoses, tubes, fittings
for leaks, kinks,
interference, etc.
3. Air in the lines