JLG 600SC_660SJC Service Manual - Manual (Page 48)

SECTION 3 - CHASSIS & TURNTABLE
3-12 – JLG Lift – 3121607
TRACK TENSION AND IDLER ROLLER DISASSEMBLY
1. Relieve all pressure from track tensioning cylinder.
2. Carefully separate track chain and lay it on the ground.
3. Remove recoil device group.
4. Remove track tension group.
5. Remove two (slide brackets) support groups and idler
pin from side frame.
6. Remove idler roller from machine.
7. Examine all fasteners and seals for damage. Replace
damaged components.
TRACK TENSION AND IDLER ROLLER REASSEMBLY
1. Clean, lubricate, and check all components for damage.
2. Reassemble idler roller with support group and fork and
install into side frame.
3. Install track tension group.
4. Torque all fasteners to correct value.
5. Reassemble track chain to side frame and lack master
pin and bushing as required.
6. Pressurize tensioning cylinder to achieve the correct
track adjustment.
7. Install cover over opening in side frame for valve used
for tensioning cylinder adjustment.
IDLER ROLLER DISASSEMBLY
NOTE: Remove recoil components to access idler roller.
1. Remove one of the dowel pins that fasten the bracket to
the shaft.
2. Remove remaining components which are now free of
shaft.
3. Press out bushing. (Bushing can only be removed by a
vertical press with correct tooling.)
4. If necessary, remove remaining dowel pins and bracket.
IDLER ROLLER ASSEMBLY (SEE FIGURE 25)
1. Press bushings into idler shell.
2. Mount a bracket on shaft.
3. Insert seal group into idler shell seal seat.
4. Install O-ring on shaft.
5. Insert complete sub assembly in idler shell to point
where it bottoms the seal group.
6. Invert idler and assemble components as in steps 1
through 4.
7. After loose assembly press tightly together using a verti-
cal press.
NOTE: Seal group is assembled same as in bottom rollers.
IDLER ROLLER AND TRACK TENSIONER REMOVAL
AND REPLACEMENT TO SIDE FRAME
SERIOUS INJURY COULD RESULT IF THE PRESSURE IS NOT RELIEVED FROM
TENSIONER AND RECOIL SYSTEM.
1. To remove pressure from cylinder, carefully back off one
or two turns on the fill fitting. As soon as lube starts to
come out vent hole STOP backing off fitting.
2. Once pressure is relieved it is safe to remove roller and
tensioner assembly.
3. Assemble fitting and fitting seal in end of each shock
assembly. Torque to chart specifications.
INSTALL SHOCK
4. Assemble shock assembly in position. Secure with bolts,
washers, and JLG Thread Locking Compound PN
0100011. Torque to 65 ft-lb +10-0 (91 Nm, +15 -0).
5. Using an adequate lifting device, pick up spring assem-
bly upright onto idler assembly. Install using bolts, wash-
ers, and JLG Thread Locking Compound PN 0100011.
Torque to 165 ft-lb +15-0 (231 Nm, +21 -0).
6. Reference offset in idler spring from centerline of idler
(to be oriented down). Using gantry crane and sling, pick
up and slide spring/idler assembly into pre-greased
slider area. Use nylon sledge hammer lightly to assem-
ble.
7. Push idler assembly against seat. Using special adapter,
pump in grease to expand shock assembly just enough
to inspect for proper assembly.