JLG 150HAX ANSI Service Manual - Manual (Page 137)

SECTION 6 - SCHEMATICS
3120679 – JLG Lift – 6-9
CONTROL VALVES
Valve Spool Sticking.
Dirt in oil causing excessive temperature build-
up. Change oil using recommended viscosity and
flush system.
Incorrect valve mounting causing
warping of the unit. Loosen valve and check mounting.
Repair as necessary.
Valve spool scored. Remove valve and repair or replace as neces-
sary.
Return spring weak or broken. Remove valve and repair or replace as neces-
sary.
Relief valve malfunctioning causing excessive
pressure within valve. Check pressure delivery to and from valve and
repair or replace as necessary.
Valve Leaking.
Dirt or other foreign material under seal. Remove and repair valve as necessary.
Valve spool scored. Repair or replace valve.
Excessive back pressure caused by restricted
return line to reservoir. Remove line and clear obstruction or replace line
as necessary.
Damaged valve seals. Repair or replace valve as necessary.
FUEL SYSTEM
Strong fuel odor during machine operation.
Fuel tank overfilled. Check fuel tank and immediately wipe up spilled
fuel.
Fuel tank damaged. Drain all fuel from tank and remove tank for
replacement or repair.
Fuel line from tank damaged. Replace fuel line.
Table 6-3.Turntable - Troubleshooting
TROUBLE PROBABLE CAUSE REMEDY