JLG 680S Service Manual - Manual (Page 74)

SECTION 3 - CHASSIS & TURNTABLE
3-26 – JLG Lift – 3121234
3.5 TORQUE HUB
Disassembly
1. Position hub over suitable container and remove
drain plugs (10) from unit. Allow oil to completely
drain, then replace drain plugs.
2. Remove eight bolts (41) and four shoulder bolts (42)
securing cover assembly to hub (7). Remove cover
assembly (23) and discard o-ring seal (22).
3. Lift carrier assembly and top thrust washer and
thrust bearing(39, 40) from hub. Thrust washer may
stick inside cover.
4. Pry ring gear (21) loose from hub and remove it.
Remove o-ring seal (22) from hub counter bore and
discard it.
5. Remove input gear (37) and thrust spacer (36) from
input shaft assembly and remove input shaft assem-
bly from hub.
6. Lift internal gear (12) and thrust washer and thrust
bearing (39, 40) from hub. Thrust washer may stick
to bottom of carrier.
7. Remove retaining ring (9) from spindle (1) and dis-
card; lift hub from spindle.
EYE PROTECTION SHOULD BE WORN DURING RETAINING RING
REMOVAL.
8. Remove inside bearing cone (6) and bearing shim
(8).
9. If necessary, pry seal (2) out of hub using screw-
driver or pry bar. With seal removed, outside bearing
cone (4) can be removed.
10. If necessary, remove inner and outer bearing cones
(3, 5) using a suitable slide hammer puller.
WHEN REBUILDING TORQUE HUB, REMOVE AND REPLACE ALL
O-RINGS AND RETAINING RINGS.
Cleaning and Inspection
1. Thoroughly clean all parts in an approved cleaning
solvent.
2. Inspect bearing cups and cones for damage, pitting,
corrosion, or excessive wear. If necessary, replace
bearings as a complete set ensuring that they
remain covered until use.
3. Inspect bearing mounting surfaces on spindle, hub,
input shaft and carrier. Replace components as nec-
essary.
4. Inspect all geared components for chipped or bro-
ken teeth and for excessive or uneven wear pat-
terns.
5. Inspect carrier for damage, especially in anti-roll pin
and planet shaft hole areas.
6. Inspect all planet shafts for scoring or other dam-
age.
7. Inspect all threaded components for damage includ-
ing stretching, thread deformation, or twisting.
8. Inspect seal mounting area in hub for burrs or sharp
edges. Dress applicable surfaces or replace compo-
nents as necessary.
9. Inspect cover for cracks or other damage, and o-
ring sealing area for burrs or sharp edges. Dress
applicable surfaces or replace cover as necessary.