Main Lift Cylinder (Sn 0300203771 Through 0300243703, Sn E300000100 Through E300005607) - JLG 400S Service And Maintenance Manual

SECTION 5 - BASIC HYDRAULICS INFORMATION & SCHEMATICS
Main Lift Cylinder (SN 0300203771 through
0300243703, SN E300000100 through E300005607)
DISASSEMBLY
DISASSEMBLY OF THE CYLINDER SHOULD BE PERFORMED ON A CLEAN WORK
SURFACE IN A DIRT FREE WORK AREA.
1. Connect a suitable auxiliary hydraulic power source to
the cylinder port block fitting.
DO NOT FULLY EXTEND CYLINDER TO THE END OF STROKE. RETRACT CYLINDER
SLIGHTLY TO AVOID TRAPPING
PRESSURE.
2. Operate the hydraulic power source and extend the
cylinder. Shut down and disconnect the power source.
Adequately support the cylinder rod, if applicable.
3. Remove the orifice plug, check valve, pressure compen-
sator valve, cartridge valves and plugs from the cylinder
port block. Discard o-rings.
4. Place the cylinder barrel into a suitable holding fixture.
ROD SUPPORT
PROTECTED ROD CLAMP
SUPPORT TABLE
Figure 5-41. Cylinder Barrel Support
5-62
BARREL CLAMP
5. Loosen and remove the setscrew which attaches the cyl-
inder head to barrel. Using a pin-face spanner wrench,
unscrew the cylinder head from the barrel.
SETSCREW
Figure 5-42. Cylinder Head Removal
6. Attach a suitable pulling device to the cylinder rod port
block end or cylinder rod end, as applicable.
EXTREME CARE SHOULD BE TAKEN WHEN REMOVING THE CYLINDER ROD,
HEAD AND PISTON. AVOID PULLING THE ROD OFF-CENTER, WHICH COULD
CAUSE DAMAGE TO THE PISTON AND CYLINDER BARREL SURFACES.
7. With the barrel clamped securely, apply pressure to the
rod pulling device and carefully withdraw the complete
rod assembly from the cylinder barrel.
Figure 5-43. Cylinder Rod Support
BARREL
CYLINDER HEAD
MAF00160
ROD SUPPORT
SUPPORT TABLE
3121671