JLG 150HAX ANSI Service Manual - Manual (Page 60)

SECTION 3 - CHASSIS & TURNTABLE
3-22 – JLG Lift – 3120679
9. Using a suitable tool, scribe a line on outer race of
swing bearing and frame. This line will aid in aligning
bearing upon installation. Remove bolts and wash-
ers which attach outer race of bearing to frame. Dis-
card bolts. Use suitable lifting equipment to remove
bearing from frame; move bearing to a clean suit-
ably supported work area.
INSTALLATION
NOTE: Manufacturing tolerances of frames and turntables
are inspected prior to the factory installation of swing
bearings to determine the need for use of Devcon
filler. When servicing machine swing bearing, apply
Devcon filler only to those machines having Devcon
previously applied at the factory. If new turntable or
frame is being installed contact manufacturer for pro-
cedures to determine the need for Devcon applica-
tion.
1. Use suitable standard tools and equipment to care-
fully remove any hardened epoxy residue from bear-
ing mounting area of frame and turntable.
2. Apply a layer of Devcon (or equivalent) filler approxi-
mately 0.125 in. (3.18 mm) thick on bearing mount-
ing plate on frame.
3. Use suitable lifting equipment to carefully lower
swing bearing into position on frame. Ensure that
scribed line of outer race of bearing aligns with
scribed mark on frame (if a new swing bearing is
used, ensure that filler plug fitting is at 90 degrees
from fore and aft centerline of frame).
4. Ensure that all frame and bearing attachment holes
are aligned, and install four diametrically opposed
bolts or clamps to secure bearing to frame. Tighten
bolts or clamps evenly in a diametrical pattern to a
torque of 20 ft. lb. (27 Nm).
5. Allow Devcon filler to cure at room temperature
(approximately 21 degrees C.) for 10 to 16 hours.
6. After the appropriate interval, release clamps or
remove bolts. Use a suitable lifting device to care-
fully remove bearing from frame.
7. Carefully remove any excess filler from frame mount-
ing area, from bearing attachment holes, and from
between gear teeth.
ENSURE THAT TURNTABLE IS ADEQUATELY SUPPORTED WHILE
APPLYING DEVCON AND WHILE INSTALLING THE BEARING.
EXTREME CARE MUST BE TAKEN DURING THE FOLLOWING STEPS
TO AVOID SERIOUS OR FATAL INJURY TO PERSONNEL.
a. Apply a layer of Devcon (or equivalent) filler
approximately 0.125 in. (3.18 mm) thick to
underside of bearing mounting area of turntable
base plate.
b. Use suitable hydraulic jacks to carefully raise
swing bearing to underside of turntable mount-
ing plate. Ensure that scribed line of inner race
of bearing aligns with scribed mark on turntable
(if a new swing bearing is used, ensure that filler
plug fitting is at 90 degrees from fore and aft
centerline of turntable).
c. Ensure that all turntable and bearing attachment
holes are aligned, and install four (4) diametri-
cally opposed clamps or bolts and nuts to
secure bearing to turntable. Tighten nuts and
bolts or clamp evenly in a diametrical pattern to
a torque of 20 ft. lb. (27 Nm).
d. Allow Devcon filler to cure at room temperature
(approximately 21 degrees C.) for 10 to 16
hours.
e. After the appropriate interval, place a suitable
hydraulic jack under bearing and release clamps
or remove nuts and bolts; use hydraulic jack to
carefully remove bearing from turntable.
f. Carefully remove excess filler from turntable
mounting area, from bearing attachment holes
and from between gear teeth.
g. Position bearing on machine frame in same
position as noted in step (c) above.
JLG INDUSTRIES RECOMMENDS THAT ALL REMOVED BEARING
NUTS AND BOLTS BE DISCARDED AND REPLACED WITH NEW
NUTS AND 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.
h. Apply a light coating of Loctite #277 to the new
bearing bolts, and loosely install bolts and wash-
ers through 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.
i. Following the Torque Sequence diagram shown
in Figure 2-8, tighten bolts to an initial torque of
410 ft. lb. (555 Nm). Then following the same
sequence tighten bolts to a final torque of 545 ft.
lb. (740 Nm).
j. Remove lifting equipment from bearing.