JLG 600SC_660SJC Service Manual - Manual (Page 133)

SECTION 6 - UNDERCARRIAGE
3120898 – JLG Lift – 6-29
Assembly
NOTE: Make sure that all of the parts of the hydraulic track
adjuster are clean and free of dirt and debris prior to
assembly.
1. Replace all o-ring seals with new o-ring seals.
NOTE: Completely fill the seal grooves in the piston with
Molybdenum Grease. The grease will displace air
when the o-rings and the backup rings are installed.
2. Install two backup rings (10), two backup rings (9)
and two o-ring seals (8) on piston (6).
NOTE: O-rings and backup rings must be installed in the
correct position in order to ensure the correct opera-
tion of the hydraulic track adjuster. Backup rings are
distinguished by the color of the ring. Backup rings
(10) are black in color. Backup rings (9) are brown in
color.
3. Apply Molybdenum Grease in the groove for lip seal
(7). Use tooling (A) to install lip seal (7). Install lip
seal (7) until the seal is 0.02 ± 0.02 inch (0.5 ± 0.5
mm) below the surface of cylinder (5). Install lip seal
(7) with the lip toward the outside of cylinder (5).
4. Make sure that all of the passages in cylinder (5) are
filled with Molybdenum Grease. Make sure that air is
not trapped in the passages in cylinder (5).
5. Install relief valve (3) in the body of the cylinder. Do
not tighten the relief valve.
6. Install fill valve (4) in the body of the cylinder. Tighten
the fill valve snugly. Do not torque the fill valve.
7. Fill the cavity of cylinder (5) with Molybdenum
Grease.
8. Put a small amount of Molybdenum grease on the
sliding surface of piston (6). Put a minimum of 4 in
3
(60cc) of Molybdenum grease on the end of the pis-
ton (6). This grease will prevent air from displacing
grease in the cylinder during installation of the pis-
ton. Make sure that the grease covers backup rings
(10) and (9) and o-rings (8).
9. Center piston (6) in cylinder (5). Insert the piston into
the cylinder.
NOTE: It may be necessary to use a soft faced hammer to
install the piston into the cylinder.
10. Make sure that grease is expelled from the vent hole
for the relief valve. Tighten relief valve (3) to a torque
of 25 ± 4 lb. ft. (34 ± 5 Nm).
11. Add approximately 0.3 in 3 (5 cc) of Molybdenum
Grease through fill valve (4). Apply a force to piston
(6) and open fill valve (4) in order to purge all the air
from the hydraulic track adjuster.
12. Tighten fill valve (4) to a torque of 34 ± 5 Nm (25 ± 4
ft. lb.).
13. Install plate assembly (1). Install two bolts (2).
14. Install the track adjuster. Refer to Disassembly and
Assembly, "Track Adjuster - Install" in this manual.
Table 6-11. Track Adjuster Required Tools - Assembly
Tool Part # Description Qty.
A 1P-0520 Driver Group 1