Service Manual Owner's manual

Table Of Contents
SECTION 3 - CHASSIS & TURNTABLE
3-110 – JLG Lift – 3121139
8. Carefully place the turntable on a suitably supported
trestle.
9. Use a suitable tool to scribe a line on the outer race
of the swing bearing and the frame. This line will aid
in aligning the bearing upon installation. Remove the
bolts and washers which attach the outer race of the
bearing to the frame. Discard the bolts. Use suitable
lifting equipment to remove the bearing from the
frame, then move the bearing to a clean, suitably
supported work area.
Swing Bearing Installation
1. Using suitable lifting equipment, carefully lower the
swing bearing into position on the frame. Ensure the
scribed line of the outer race of the bearing aligns
with the scribed line on the frame. If a new swing
bearing is used, ensure that the spot with minimum
gear backlash (marked with yellow paint) is towards
the centerline of the swing drive (as close as the bolt
pattern will allow).
JLG INDUSTRIES RECOMMENDS THAT ALL REMOVED BEARING
BOLTS BE DISCARDED AND REPLACED WITH NEW BOLTS. SINCE
THE SWING BEARING IS THE ONLY STRUCTURAL LINK BETWEEN
THE FRAME AND TURNTABLE, IT IS IMPERATIVE THAT SUCH
REPLACEMENT HARDWARE MEETS JLG SPECIFICATIONS. USE
OF GENUINE JLG HARDWARE IS HIGHLY RECOMMENDED.
2. Apply a light coating of Loctite #271 to the new
bearing bolts, and loosely install the bolts and wash-
ers through the frame and outer race of bearing.
IF COMPRESSED AIR OR ELECTRICALLY OPERATED IMPACT
WRENCH IS USED FOR TIGHTENING THE BEARING ATTACHMENT
BOLTS, THE TORQUE SETTING ACCURACY OF THE TOOL SHOULD
BE CHECKED PRIOR TO USE.
3. Refer to the Torque Sequence diagram as shown in
Figure 3-55., Swing Bearing Torque Sequence.
Spray a light coat of Safety Solvent 13 on the new
bearing bolts. Then apply a light coating of Loctite
#271 to the new bearing bolts, and install the bolts
and washers through the frame and outer race of the
bearing. Tighten the bolts to a torque of 190 Ft. lbs.
(258 Nm) w/Loctite.
4. Remove the lifting equipment from the bearing.
5. Using suitable lifting equipment, carefully position
the turntable assembly above the machine frame.
6. Carefully lower the turntable onto the swing bearing,
ensuring that the scribed line of the inner race of the
bearing aligns with scribed line on the turntable. If a
new swing bearing is used, ensure that the filler plug
fitting is at 90 degrees from the fore and aft center
line of the turntable.
7. Spray a light coat of Safety Solvent 13 on the new
bearing bolts. Then apply a light coating of Loctite
#271 to the new bearing bolts, and install the bolts
and washers through the turntable and inner race of
the bearing.
8. Following the Torque Sequence diagram shown in
Figure 3-55., Swing Bearing Torque Sequence,
tighten the bolts to a torque of 190 Ft. lbs. (258 Nm)
w/Loctite.
9. Remove the lifting equipment.
10. Install the rotary coupling retaining yoke brackets,
apply a light coating of Loctite #242 to the attaching
bolts and secure the yoke to the turntable with the
mounting hardware.
11. Connect the hydraulic lines to the rotary coupling as
tagged prior to removal.
12. At ground control station, use boom lift control to
lower boom to stowed position.
13. Using all applicable safety precautions, activate the
hydraulic system and check the swing system for
proper and safe operation.
Swing Bearing Torque Values
1. Outer Race - 190 ft. lbs. (258 Nm) w/Loctite.
2. Inner Race - 190 ft. lbs. (258 Nm) w/Loctite.
3. See Swing Bearing Torquing Sequence.
CHECK THE INNER AND OUTER SWING BEARING BOLTS FOR
MISSING OR LOOSENESS AFTER FIRST 50 HOURS OF OPERA-
TION, AND EVERY 600 HOURS THEREAFTER.