JLG M400 ANSI Service Manual - Manual (Page 84)

SECTION 3 - CHASSIS & TURNTABLE
3-42 – JLG Lift – 3121125
2. Installation.
a. Install bearing to rotation box with two cap-
screws, so that fill plug of bearing is as close to
gear as bolt pattern will allow. Do not tighten
capscrews.
b. Line up high spot (blue) of bearing with center
tooth of worm gear. Set backlash to 0.008 -
0.010 inch (0.20 - 0.25 mm). Tighten capscrews
as shown in Figure 3-15., Swing Bearing Torqu-
ing Sequence.
c. Apply Tribol Molub-Alloy 936 Open Gear Com-
pound to bearing and worm gear teeth.
d. Grease bearing with Mobilith SHC Bearing
Grease. Grease fitting is on inside wall of inner
race of bearing.
NOTE: If Tribol Molub-Alloy 936 Open Gear Compound or
Mobilith SHC Bearing Grease are not available,
Multi-Purpose Grease (MPG) can be substituted,
however the service interval will be shorter.
e. Using suitable lifting equipment, install bearing/
rotation box assembly to frame with soft spot
(red) 90 degree relative to load axis. If reusing
old bearing, ensure that scribed line of outer
race of the bearing aligns with the scribed mark
on the frame.
JLG INDUSTRIES RECOMMENDS THAT ALL REMOVED GRADE 8
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 TURN-
TABLE, IT IS IMPERATIVE THAT SUCH REPLACEMENT HARD-
WARE MEETS JLG SPECIFICATIONS. USE OF GENUINE JLG
HARDWARE IS HIGHLY RECOMMENDED.
f. Apply a light coating of Loctite 271 to the new
bearing bolts and loosely install the bolts and
washers 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.
g. Following the torque sequence diagram shown
in Figure 3-15., tighten the bolts to an initial
torque of 130 ft. lbs. (175 Nm). Then following
the same sequence, tighten to a final torque of
190 ft. lbs. (260 Nm).
h. Remove lifting equipment from bearing.
Figure 3-15. Swing Bearing Torquing Sequence