JLG 450A_AJ Series II Service Manual - Manual (Page 291)

SECTION 5 - HYDRAULICS
3121290 – JLG Lift – 5-51
Axle Lockout Cylinder
Refer to Figure 5-106., Axle Lockout Cylinder.
DISASSEMBLY
CONTAMINATION MAY DAMAGE EQUIPMENT. DISASSEMBLE CYLINDER ON A
CLEAN WORK SURFACE IN A DIRT FREE WORK AREA.
PISTON CAN FALL OUT OF HOUSING AND CAUSE INJURY
OR DAMAGE TO EQUIPMENT. BE CAREFUL WHEN REMOV-
ING AXLE CYLINDER. OPENING BLEED VALVE CAN CAUSE
PISTON TO FALL OUT OF HOUSING.
1. Open bleed valve (8). Rotate piston (2) and remove from
housing (1).
2. Remove wiper (6). Do not scratch housing bore.
3. Remove two wear rings (5) and rod seal (7) from grooves
in piston bore. Do not scratch housing bore.
4. Remove check valve (9), if required.
CLEANING AND INSPECTION
1. Inspect bore and piston for scoring, pitting, or excessive
wear.
2. Remove minor surface blemishes with wet 2000-grit
sandpaper. Pitting requires replacement of housing or
piston.
3. Clean all parts with approved solvent and dry with com-
pressed air.
ASSEMBLY
Refer to Figure 5-106., Axle Lockout Cylinder.
1. Install two new wear rings (5) and rod seal (7) in piston
bore grooves. Make sure they are not twisted.
2. Install new wiper (6) in housing.
3. Lubricate piston bore with clean hydraulic fluid.
INSERTING PISTON OFF-CENTER CAN DAMAGE PISTON AND PISTON BORE
SURFACES. USE EXTREME CARE WHEN INSTALLING PISTON.
4. Install piston (2) in bore and push to top of bore.
5. Install check valve (9). Torque to 25 - 27 ft-lb (33 - 36 Nm).
6. Bleed system. Refer to 3.6, Oscillating Axle Bleeding Pro-
cedure and Lockout Test.