JLG 260MRT Service Manual - Manual (Page 35)

SECTION 2 - PROCEDURES
3121801 – JLG Lift – 2-13
2.11 STEER CYLINDER REPAIR
Removal
Before beginning this procedure, ensure that the parking
brake is engaged and the rear wheels are chocked.
1. Tag and disconnect the hydraulic lines to the steer
cylinder, then cap the steer cylinder hydraulic lines
and ports.
2. At each steer spindle, remove the bolt and lock nut
securing the steer cylinder to the spindle.
3. When the steer cylinder is disconnected from the
steer spindles, turn each wheel by hand to give
clearance to remove the steer cylinder from the front
axle.
4. Carefully lift the steer cylinder until the cylinder
mounting block clears the mounting slot in the bot-
tom of the axle, then slowly remove the cylinder from
the axle and place it in a suitable work area.
Disassembly
DISASSEMBLY OF THE CYLINDER SHOULD BE PERFORMED ON
A CLEAN WORK SURFACE IN A DIRT FREE WORK AREA.
1. Place the cylinder barrel into a suitable holding fix-
ture.
2. Using a suitable chain wrench, carefully remove the
cylinder head retainer from one end of the cylinder
barrel.
3. Attach a suitable pulling device to one end of the
cylinder rod.
EXTREME CARE SHOULD BE TAKEN WHEN REMOVING THE CYL-
INDER ROD, SPACER, AND PISTON. AVOID PULLING THE ROD
OFF-CENTER, WHICH COULD CAUSE DAMAGE TO THE PISTON
AND CYLINDER BARREL SURFACES.
4. With the barrel clamped securely, apply pressure to
the rod pulling device and carefully withdraw the
complete rod assembly from the cylinder barrel.
5. Using a suitable chain wrench, carefully remove the
remaining cylinder head retainer from the opposite
end of the cylinder barrel. Remove the head and
remove and discard the wiper, rod seal, 0-ring and
wear ring.
6. Using suitable protection, clamp the cylinder rod in
a vise or similar holding fixture.
7. Carefully remove the head from the cylinder rod and
remove and discard the wiper, rod seal, o-ring and
wear ring.
8. Carefully remove the spacers from the cylinder rod,
then remove the retaining rings securing the piston
in place on the cylinder rod. Discard the retaining
rings.
9. Carefully remove the piston from the cylinder rod.
Remove and discard the T-seal and o-ring.
10. Remove the cylinder rod from the holding fixture.
Cleaning and Inspection
1. Clean all parts thoroughly in an approved cleaning
solvent.
2. Inspect the cylinder rod for scoring, tapering, ovality,
or other damage. If necessary, dress the rod with
Scotch Brite or equivalent. Replace the rod if neces-
sary.
3. Inspect the threaded portion of the rod for excessive
damage. Dress the threads as necessary.
4. Inspect the inner surface of the cylinder barrel tube
for scoring or other damage. Check the inside diam-
eter for tapering or ovality. Replace the barrel if nec-
essary.
5. Inspect the piston surface for damage, scoring and
distortion. Dress the piston surface or replace the
piston as necessary.
6. Inspect the seal and o-ring grooves in the piston for
burrs and sharp edges. Dress applicable surfaces
as necessary.
7. Inspect the inside diameter of the spacers and
heads for scoring or other damage and for ovality
and tapering. Replace as necessary.
8. Inspect the seal and o-ring grooves in the heads for
burrs and sharp edges. Dress applicable surfaces
as necessary.
9. Inspect the outside diameter of the spacers and
heads 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.
11. Inspect the cam follower for wear or damage.
Replace as necessary.