Swing Bearing Removal; Swing Bearing Installation - JLG 400S Service And Maintenance Manual

Swing Bearing Removal

1. From ground control station, operate the boom ade-
quately to provide access to frame opening to rotary
coupling.
NEVER WORK BENEATH THE BOOM WITHOUT FIRST ENGAGING BOOM SAFETY
PROP OR PROVIDING ADEQUATE OVERHEAD SLING SUPPORT AND/OR BLOCK-
ING.
2. Attach an adequate support sling to the boom and draw
all slack from sling. Prop or block the boom if feasible.
3. From inside turntable, remove mounting hardware from
rotary coupling mount bracket.
4. Tag and disconnect the hydraulic lines from the fittings
on the top of the rotary coupling. Use a suitable con-
tainer to retain any residual hydraulic fluid. Cap or plug
all openings of hydraulic lines and port.
5. Disconnect wiring harness connected to the rotary cou-
pling and tag and disconnect remote grease fitting line
(if equipped).
6. Attach suitable overhead lifting equipment to the base
of the turntable weldment. See "Swing Bearing Removal
(400S)"
7. Use a suitable tool to scribe a line on the inner race of
the swing bearing and on the underside of the turnta-
ble. This will aid in aligning the bearing upon installa-
tion. Remove the bolts and washers which attach the
turntable to the bearing inner race. Discard the bolts.
8. Use the lifting equipment to carefully lift the complete
turntable assembly from the bearing. Ensure that no
damage occurs to the turntable, bearing or frame-
mounted components.
9. Carefully place the turntable on a suitably supported
trestle.
NOTE: The swing bearing approximately weighs 138 lbs. (55 kg).
10. 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.
3121671
SECTION 3 - CHASSIS & TURNTABLE

Swing Bearing Installation

NOTE: The swing bearing approximately weighs 138 lbs. (55 kg).
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 filler plug fitting is at 90 degrees
from the fore and aft center line of the frame.
JLG INDUSTRIES RECOMMENDS THAT ALL REMOVED BEARING BOLTS BE DIS-
CARDED AND REPLACED WITH NEW BOLTS. SINCE THE SWING BEARING IS THE
ONLY STRUCTURAL LINK BETWEEN THE FRAME AND TURNTABLE, IT IS IMPER-
ATIVE THAT SUCH REPLACEMENT HARDWARE MEETS JLG SPECIFICATIONS.
USE OF GENUINE JLG HARDWARE IS HIGHLY RECOMMENDED.
2. Apply a light coating of JLG Threadlocker P/N 0100019
to the new bearing bolts and loosely install the bolts
and washers through the frame and outer race of bear-
ing.
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 Fig-
ure 3-63., Swing Bearing Torque Sequence. Clean any
residue off the new bearing bolts, then apply a light
coating of JLG Threadlocker P/N 0100019 and install the
bolts and washers through the frame and outer race of
the bearing. Tighten the bolts to an initial torque of
190 ft. lbs. (258 Nm) w/JLG Threadlocker P/N 0100019.
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 fit-
ting is at 90 degrees from the fore and aft center line of
the turntable.
7. Clean any residue off the new bearing bolts, then apply
a light coating of JLG Threadlocker P/N 0100019 and
install the bolts and washers through the turntable and
inner race of the bearing.
8. Following the Torque Sequence diagram shown in Fig-
ure 3-63., Swing Bearing Torque Sequence, tighten the
bolts to a torque of 190 ft. lbs. (258 Nm).
9. Remove the lifting equipment.
3-85