JLG 450A_AJ Series II Service Manual - Manual (Page 272)

SECTION 5 - HYDRAULICS
5-32 – JLG Lift – 3121290
Platform Level (Slave) Cylinder With Arctic Package
Refer to Figure 5-63.
DISASSEMBLY
CONTAMINATION MAY DAMAGE EQUIPMENT. DISASSEMBLE CYLINDER ON A
CLEAN WORK SURFACE IN A DIRT FREE WORK AREA.
1. Connect a suitable auxiliary hydraulic power source to
cylinder port block fitting.
DO NOT FULLY EXTEND CYLINDER TO THE END OF STROKE. RETRACT CYLINDER
SLIGHTLY TO AVOID TRAPPING PRESSURE.
2. Operate hydraulic power source and extend cylinder.
Shut down and disconnect power source. Adequately
support cylinder rod, if applicable.
3. Remove cartridge-type holding valve and fittings from
cylinder port block. Discard O-rings.
4. Place cylinder barrel in a suitable holding fixture. Tap
around outside of cylinder head retainer with a suitable
hammer to break thread-locking compound.
Figure 5-60. Cylinder Barrel Support
5. Mark cylinder head and barrel with a center punch for
reassembly. Remove eight cylinder head retainer cap
screws from cylinder barrel.
Figure 5-61. Marking Cylinder for Alignment
PULLING ROD OFF-CENTER CAN DAMAGE PISTON AND CYLINDER BARREL SURFACES.
USE EXTREME CARE WHEN REMOVING CYLINDER ROD, HEAD, AND PISTON.
6. Clamp barrel securely. Pull rod assembly from barrel.
Figure 5-62. Cylinder Rod Support