JLG 150HAX Service Manual - Manual (Page 96)

SECTION 4 - BOOM & PLATFORM
4-16 – JLG Lift – 3120817
8. Chain Anchors, Sheaves, and Pins: An inspection
of the chain must include a close examination of
chain anchors and sheaves. Check chain anchors
for wear breakage and misalignment. Anchors with
worn or broken fingers should be replaced. They
should also be adjusted to eliminate twisting the
chain for an even load distribution.
Sheaves should be inspected for worn flanges,
which would indicate misalignment, and wear on the
outside diameter of the sheave. A worn sheave can
mean several problems, as follows:
1. Chains too tight.
2. Sheave bearings/pin bad.
3. Bent/misaligned chains.
4.3 WEAR PADS
Shim up wear pads to within 5/16 in. (0.8 mm) tolerance
between wear pad and adjacent surface.
Replace wear pads when worn within 1/8 in. (3.2 mm) of
threaded insert.
4.4 PLATFORM ROTATOR BRAKE
The platform rotator is equipped with a brake, which uses
a stack of belleville washers to apply friction to the plat-
form pivot point. To ensure proper friction, torque bolt
securing belleville washers to 140 ft. lb. (190 Nm).
Table 4-1. Chain Stretch Tolerance
CHAIN
SIZE
PIN TO PIN
MEASUREMENT
ALLOWABLE
STRETCH
14 IN (36 CM) SPAN
0.50 in. pitch
(1.27 cm)
14 in. (36 cm)
or 28 pitches
0.42 in.
(1.07 cm)
1.00 in. pitch
2.54 cm
14 in. (36 cm)
or 14 pitches
0.42 in.
(1.07 cm)
1.75 in. pitch
(4.45 cm)
14 in. (36 cm)
or 8 pitches
0.42 in.
1.07 cm
2.00 in. pitch
(5.08 cm)
14 in. (36 cm)
or 7 pitches
0.42 in.
1.07 cm