JLG 450A_AJ Series II Service Manual - Manual (Page 120)

SECTION 3 - CHASSIS & TURNTABLE
3-70 – JLG Lift – 3121180
IF COMPRESSED AIR OR ELECTRICALLY OPERATED IMPACT
WRENCH IS USED TO TIGHTEN BEARING ATTACHMENT BOLTS,
CHECK TORQUE SETTING ACCURACY OF TOOL BEFORE USE.
7. Tighten bolts to an initial torque of 130 ft-lb (176 Nm)
following torque sequence shown in Figure 3-50.,
Swing Bearing Torque Sequence. Tighten to a final
torque of 190 ft-lb (257 Nm) following same
sequence.
8. Remove lifting equipment from bearing.
9. Use suitable lift equipment to carefully position turn-
table assembly above machine frame.
10. Carefully lower turntable onto swing bearing. Ensure
scribed line of inner race of bearing aligns with
scribed mark on turntable. If a new swing bearing is
used, ensure filler plug fitting is at 90 degrees from
fore and aft centerline of turntable.
11. Apply a light coating of Loctite 271 to new bearing
bolts and install through turntable and inner race of
bearing.
12. Tighten bolts to an initial torque of 130 ft-lb (176 Nm)
following torque sequence shown in Figure 3-52.
Tighten to a final torque of 190 ft-lb (257 Nm) follow-
ing same sequence.
13. Remove lift equipment.
14. Route hydraulic lines through center of turntable and
frame. Connect as tagged prior to removal.
15. Following all applicable safety precautions, activate
hydraulic system and functionally check swing sys-
tem for proper and safe operation.
Turntable Bearing Mounting Bolt Condition
Check
NOTE: This check is designed to replace existing bearing
bolt torque checks on JLG Lifts in service. This
check must be performed after first 50 hours of
machine operation and every 600 hours of machine
operation thereafter. Replace missing or loose bolts
with new bolts and torque to value specified in
torque chart after lubricating bolt threads with Loctite
#271. After replacing and re-torquing bolt or bolts,
recheck all existing bolts for looseness.
Check Frame To Bearing Bolts
1. Fully retracted boom and elevate to 70 degrees (full
elevation).
2. Try and insert a 0.0015" feeler gauge between bolt
head and hardened washer at positions shown in
Figure 3-51., Swing Bearing Feeler Gauge Check.
3. Ensure 0.0015" feeler gauge will not fit under bolt
head to bolt shank.
4. Swing turntable 90 degrees, and check some
selected bolts at the new position.
5. Continue rotating turntable at 90 degrees intervals
until a sampling of bolts have been checked in all
quadrants.
3
7 21
17
13
9
5
1
24
20
16
12
22
18
14
10
6
2
23
19
15
11
8 4
17
13
9
5
1
16
12
18
14
10
6
2
15
7
3
11
8
4
Figure 3-50. Swing Bearing Torque Sequence
.0015" Feeler Gauge
Figure 3-51. Swing Bearing Feeler Gauge Check