JLG 3246E2 ANSI Service Manual - Manual (Page 24)

SECTION 2 - PROCEDURES
2-10 – JLG Lift – 3120737
8. Inspect seal and o-ring grooves in guide for burrs
and sharp edges. Dress applicable surfaces as nec-
essary.
9. Inspect cylinder guide outside diameter for scoring
or other damage and ovality and tapering. Replace
as necessary.
10. Inspect the oil ports for blockage or the presence of
dirt or other foreign material. Repair as necessary.
Assembly
NOTE: Prior to cylinder assembly, ensure that the proper
cylinder seal kit is used.
Apply a light film of hydraulic oil to all components
prior to assembly.
1. Using suitable protection, clamp the cylinder rod in
a vise or similar holding fixture.
2. Place a new wiper ring, rod seal, o-ring, and back-up
ring into the applicable cylinder guide grooves.
3. Carefully install the guide on the rod, ensuring that
the wiper ring and rod seal are not damaged or dis-
lodged. Push the guide onto the rod.
4. Place a new piston ring and o-rings on the piston.
5. Carefully place the piston on the threaded end of the
cylinder rod, ensuring that the o-ring is not damaged
or dislodged. Push the piston onto the rod as far as
it will go.
6. Install the piston locknut on the threaded end of the
cylinder rod and torque to 100-120 ft. lb. (136-163
Nm).
7. Remove the cylinder rod from the holding fixture.
8. Position the cylinder barrel in a suitable holding fix-
ture.
EXTREME CARE SHOULD BE TAKEN WHEN INSTALLING THE
CYLINDER ROD, GUIDE, AND PISTON. AVOID PULLING THE ROD
OFF-CENTER, WHICH COULD CAUSE DAMAGE TO THE PISTON
AND CYLINDER BARREL SURFACES.
9. With the barrel clamped securely, and while ade-
quately supporting the cylinder rod, insert the piston
end of the rod into the cylinder barrel. Ensure that
the piston ring and o-ring are not damaged or dis-
lodged.
10. Continue pushing the rod into the barrel until the cyl-
inder guide can be inserted into the cylinder barrel.
11. Using all applicable safety precautions, secure the
cylinder rod assembly with a new retaining ring.
12. Reconnect the hydraulic hoses to the applicable cyl-
inder ports.
2.12 STEER CYLINDER REPAIR
Disassembly
DISASSEMBLY OF THE CYLINDER SHOULD BE PERFORMED ON
A CLEAN WORK SURFACE IN A DIRT FREE WORK AREA.
DO NOT FULLY EXTEND CYLINDER TO END OF STROKE.
RETRACT CYLINDER SLIGHTLY TO AVOID TRAPPING PRES-
SURE.
1. Place the cylinder barrel into a suitable holding fix-
ture.
2. Using a suitable hammer, tap around the outside of
the cylinder barrel and guide to shatter the Loctite.
3. Using a suitable spanner wrench, carefully remove
the guide from the rod clevis end of the cylinder bar-
rel.
4. Attach a suitable pulling device to the clevis end of
cylinder rod section one.
EXTREME CARE SHOULD BE TAKEN WHEN REMOVING THE CYL-
INDER ROD, GUIDE, AND PISTON. AVOID PULLING THE ROD
OFF-CENTER, WHICH COULD CAUSE DAMAGE TO THE PISTON
AND CYLINDER BARREL SURFACES.
5. With the barrel clamped securely, apply pressure to
the rod pulling device and carefully withdraw the
complete rod assembly from the cylinder barrel.
6. Using a suitable hammer, tap around the outside of
the cylinder barrel and guide to shatter the Loctite.
7. Using a suitable spanner wrench, carefully remove
the remaining guide from the cylinder barrel.
Remove and discard the wiper ring, rod seal, back-
up ring and o-ring.
8. Using suitable protection, clamp cylinder rod sec-
tion two in a vise or similar holding fixture.
9. Carefully remove cylinder rod section one from cyl-
inder rod section two and carefully remove the pis-
ton from the cylinder rod. Remove and discard the
piston seal and o-ring.
10. Carefully remove the guide from cylinder rod section
one. Remove and discard the o-ring, back-up ring,
rod seal, and wiper ring.