JLG 680S, Service And Maintenance Manual

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SECTION 3 - CHASSIS & TURNTABLE
3121234 3-51
3.9 DRIVE 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 counterbore and discard it.
5. Remove input gear (37) and thrust spacer (36) from
input shaft assembly and remove input shaft assembly
from hub.
6. Lift internal gear (12) and thrust washer and thrust bear-
ing (39, 40) from hub. Thrust washer may stick to bottom
of carrier.
7. Remove retaining ring (9) from spindle (1) and discard;
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 screwdriver 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 DRIVE HUB, REMOVE AND REPLACE ALL O-RINGS AND
RETAINING RINGS.
Cleaning and Inspection
1. Thoroughly clean all parts in an approved cleaning sol-
vent.
2. Inspect bearing cups and cones for damage, pitting, cor-
rosion, 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 neces-
sary.
4. Inspect all geared components for chipped or broken
teeth and for excessive or uneven wear patterns.
5. Inspect carrier for damage, especially in anti-roll pin and
planet shaft hole areas.
6. Inspect all planet shafts for scoring or other damage.
7. Inspect all threaded components for damage including
stretching, thread deformation, or twisting.
8. Inspect seal mounting area in hub for burrs or sharp
edges. Dress applicable surfaces or replace components
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.
Repair
1. Cover Assembly:
a. Remove two bolts (25) securing disconnect cap (26)
to cover (23) and remove cap.
b. Remove two bolts (25) securing cover cap (24) to
cover and remove cap.
c. Remove disconnect rod (27) from cap and remove
o-rings (28, 29) from cover cap. Discard o-rings.
d. If necessary, remove pipe plug (30) from cover.
e. Clean and inspect parts in accordance with Clean-
ing and Inspection procedures. Replace parts as
necessary.
f. If removed, screw pipe plug into cover.
g. Slip o-ring (29) over cover cap and against face.
h. Place o-ring (28) into cover cap internal groove. Dis-
connect rod may be used to push o-ring into
groove.
i. Place cover cap into cover with large hole located
over pipe plug. Secure cover cap to cover with two
bolts. Torque bolts to 70-80 in. lbs. (7.9-9.0 Nm).