Swing Bearing; Turntable Bearing Mounting Bolt Condition Check - JLG 1200SJP Service And Maintenance Manual

3.22 SWING BEARING

Turntable Bearing Mounting Bolt Condition
Check
THE SWING BEARING IS ONE OF THE MOST CRITICAL POINTS ON AN AERIAL
LIFT. IT IS HERE THAT THE STRESSES OF LIFTING ARE CONCENTRATED, AT THE
CENTER OF ROTATION. BECAUSE OF THIS, PROPER MAINTENANCE OF THE
SWING BEARING BOLTS IS A MUST FOR SAFE OPERATION.
NOTE: This check is designed to replace the existing bearing bolt
torque checks on JLG Lifts in service. This check must be
performed after the first 50 hours of machine operation
and every 600 hours of machine operation thereafter. If
during this check any bolts are found to be missing or
loose, replace missing or loose bolts with new bolts and
torque to the value specified in the torque chart, after
applying JLG Threadlocker PN 0100019 to the bolt threads.
After replacing and retorquing bolt or bolts recheck all
existing bolts for looseness.
1. Check the frame to bearing attach bolts as follows:
a. Fully elevate the main boom. (See Figure 3-63.)
b. At the position indicated on Figure 3-63., try to
insert a 0.0015 feeler gauge between the bolt and
hardened washer at the arrow indicated position.
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SECTION 3 - CHASSIS & TURNTABLE
c. Ensure that the 0.0015" feeler gauge will not pene-
trate under the bolt head to the bolt shank.
d. Swing the turntable 90 degrees, and check some
selected bolts at the new position.
e. Continue rotating the turntable at 90 degrees inter-
vals until a sampling of bolts have been checked in
all quadrants.
2. Check the turntable to bearing Attach bolts as follows:
a. Elevate the fully retracted main boom to full eleva-
tion.
b. At the position indicated on Figure 3-65. try to insert
the 0.0015" feeler gauge between the bolt head and
hardened washer at the arrow indicated position.
c. Lower the boom to horizontal and fully extend the
boom.
d. At the position indicated on Figure 3-64., try and
insert the 0.0015" feeler gauge between the bolt
head and hardened washer at the arrow indicated
position.
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