JLG 1100SB Service Manual - Manual (Page 139)

SECTION 3 - CHASSIS & TURNTABLE
3121265 – JLG Lift – 3-97
Wear Tolerance
1. From the underside of the machine, at rear center,
with the main boom fully elevated and fully retracted,
as shown in Figure 3-50., Swing Bearing Tolerance
Boom Placement - Sheet 1 of 2, set up a magnetic
base dial indicator as shown below and set the indi-
cator to 0 (zero).
2. Next, position the main boom fully extended and
horizontal as shown in Figure 3-51., Swing Bearing
Tolerance Boom Placement - Sheet 2 of 2. Read the
measurement recorded on the dial indicator gauge.
3. If the measurement is greater than 0.094 in. (2.387
mm), the swing bearing should be replaced.
4. If the measurement is less than 0.094 in. (2.387
mm), and any of the following conditions exist, the
bearing should be removed, disassembled, and
inspected for the following:
a. Metal particles in the grease.
b. Increased drive power required.
c. Noise.
d. Rough rotation.
5. If bearing inspection shows no defects, reassemble
and return to service.
Swing Bearing Removal
1. From Ground Control station, operate the boom
adequately 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 BLOCKING.
2. Attach an adequate support sling to the boom and
draw all slack from sling. Prop or block the boom if
feasible.
HYDRAULIC LINES AND PORTS SHOULD BE CAPPED IMMEDI-
ATELY AFTER DISCONNECTING LINES TO AVOID THE ENTRY OF
CONTAMINANTS INTO THE SYSTEM.
3. Tag and disconnect the hydraulic lines from the fit-
tings on the top of the rotary coupling. Use a suit-
able container to retain any residual hydraulic fluid.
Immediately cap lines and ports.
HYDRAULIC LINES AND PORTS SHOULD BE CAPPED IMMEDI-
ATELY AFTER DISCONNECTING LINES TO AVOID THE ENTRY OF
CONTAMINANTS INTO THE SYSTEM.
4. From inside turntable, remove mounting hardware
which attach rotary coupling retaining yoke brackets
to turntable.
Figure 3-52. Swing Bolt Feeler Gauge Check