Disassembly - JLG T500J Service And Maintenance Manual

Disassembly

DO NOT ATTEMPT TO SERVICE A HYDRAULIC C YLINDER WHILE IT IS
INSTALLED. THE CYLINDER MUST BE REMOVED FROM THE MACHINE AND ALL
PRESSURE MUST BE RELIEVED. AIR MUST NOT BE USED TO EXTEND OR
RETRACT THE CYLINDER. SAFETY GLASSES MUST BE WORN AT ALL TIMES BY
SERVICE PERSONNEL.
1. The cylinder should be secured in such a way as to pre-
vent rotation of the barrel while unscrewing the head
gland. Care should be taken to avoid damaging the rod
surface and to avoid excessive deformation of the barrel,
which could permanently damage the unit. Make sure
to support the rod during removal.
ROD SUPPORT
PROTECTED ROD CLAMP
SUPPORT TABLE SUPPORT TABLE
Figure 5-3. Cylinder Barrel Support
2. Remove all dirt, grease, and other contaminants from
around the ports and the head gland. Drain all oil from
the unit. Extending and retracting the rod manually can
help purge the bulk of the remaining oil.
3121200
SECTION 5 - BASIC HYDRAULIC INFORMATION & SCHEMATICS
BARREL CLAMP
3. Mark the orientation of the rod, gland, and barrel with a
permanent marker or paint pen. Do not apply any paint
on the chromed surface of the rod. Unscrew the head
gland from the cylinder assembly using a spanner
wrench in the holes provided in the OD of the head
gland.
Figure 5-4. Cylinder Head Removal
NOTE: The threads are locked with a non-permanent thread
adhesive during assembly. A quick tug on the wrench may
be necessary to release the thread adhesive.
4. Remove the rod assembly from the barrel using care not
to damage the threads or any other component surface.
ROD SUPPORT
Figure 5-5. Cylinder Rod Support
5. Clamp the rod mount and support the rod assembly
with the chrome surface protected. Remove the piston
assembly either by unthreading the locknut with a
socket wrench or the piston itself from the rod using a
spanner wrench depending on the cylinder model.
MAE29480
SUPPORT TABLE
5-5