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Section

4-22

LX 31/41 Work Platform

Maintenance

4.11 Steering Cylinder

(Figure 4-22)

REMOVAL

1. Remove the two capscrews holding the front axle

cover in place (4WD only).

2. Remove and cap the hoses. Mark them for refer-

ence.

3. Remove the hair pin retainers from the clevis pins at

each end of the cylinder.

4. Remove the clevis pins.
5. Remove the cylinder from the chassis.

SEAL REPLACEMENT (FIGURE 4-23)

Note: Provide a clean work area for this operation,

and observe clean assembly practices. Seals and

hydraulic cylinder components are highly sensi-

tive to contamination that may not even be

visible to the naked eye.

1. Use a spanner wrench to rotate the head until the

retaining ring becomes visible in the grove milled

into the side of the cylinder. Insert a screwdriver

under the beveled edge of the retaining ring to start

it through the opening. Continue to rotate the head

until the retaining ring works it's way out of the

opening.

2. Remove the rod, head, and piston from the tube.
3. Unscrew the locknut from the end of the rod.
4. Remove the piston from the rod.
5. Slide the rod out of the head.
6. Remove all of the old seals and wear rings, discard.
7. Thoroughly clean all parts with solvent. Rinse the

inside of the tube and allow to drain. A high pres-

sure rinse and wipe with a lint free rag is preferable.

8. Inspect the rod, head, piston, and tube for

scratches, pits, or polishing. Check seal groves and

sealing surfaces. Scratches or pits deep enough to

catch the fingernail are unacceptable, replace the

affected component. Polishing is a sign of uneven

loading, when this occurs, the surface should be

checked for roundness. Surfaces not round within

.007" should be replaced.

9. Lubricate all components and seals with clean

hydraulic oil prior to assembly.

Note: During seal replacement steps, do not use

sharp edged tools to avoid cutting the seals. After

assembling all seals, allow at least one hour for the

seals to elastically restore to their original shape

before assembly. Refer to Figure 4-16 for component

identification and placement.

10. Stretch the o-ring loader into the seal grove on the

piston. Verify that it has not been twisted or

pinched. Start one edge of the bidirectional piston

seal into the grove in the piston and work it around

into the grove with your thumbs. Be very careful

not to cut the outer diameter of this seal.

11. Install the wear ring into the grove on the piston.
12. Twist the u-cup seal into a 'C' shape and snap it into

the grove inside of the head. Note that the 'U'

groove in the seal should face the inside of the

cylinder.

13. Use the above technique to install the wiper into the

groove inside the head. Note that the blade of the

wiper should face toward the outside of the cylinder.

14. Install the static backup ring into the groove closest

to the inside edge of the head.

15. Install the static o-ring into the above groove, making

sure that it falls inside of the static backup ring.

16. Slide the head onto the rod.
17. Install the static o-ring onto the end of the rod.
18. Install the piston onto the rod.
19. Install the locknut onto the rod, torque to 250 ft.-lbs.
20. Slide the piston, rod, and head into the tube. Be

careful not to damage any of the seals during assem-

bly. If necessary, use shimstock to prevent the seals

from extruding into the retaining ring slot.

21. Using a spanner wrench, rotate the head until the

retaining ring hole is visible in the groove milled into

the side of the cylinder. Insert the retaining ring

hook into the hole and rotate the head 1-

turns

until the retaining ring is drawn completely into the

tube and the ends are covered.

INSTALLATION

1. Align the ends of the cylinder with the mounts on