Lull 944E-42, Service Manual

Page: 84 / 844

Boom
3.38 Model 644E-42/944E-42 Rev. 6/04
a. Component/Assembly Verification
The inner to intermediate boom separation should be
checked when assembling new boom sections or chains,
or when the rear retract chain clevis has been moved
forward on the anchor plate.
Measure the separation between the inner and
intermediate boom top plates (1). The distance should be
at least 8-1/2" (216 mm) and not greater than 9-1/2"
(241 mm) with the boom fully retracted and the chains
properly tensioned. A distance of less than 8-1/2"
(216 mm) could result in interference and cause damage
to other boom components.
If the distance is less than 8-1/2" (216 mm):
1. Tighten the retract chain locknut (3) on the bottom of
the outer boom one or two turns.
2. Measure the distance and tighten until the distance
is between 8-1/2" (216 mm) and 9-1/2" (241 mm). If
the locknut cannot be tightened any more, loosen
the locknut until one full thread on the clevis
protrudes beyond the elastic collar of the locknut.
3. Verify that the extend chain clevis (4) is not mounted
in the last hole (5) in the anchor plate (6). If the clevis
can be moved to the next hole, do so and check the
chain tension. (Refer to Section 3.4.3, “Boom Chain
Tension Check,” and Section 3.4.4, “Boom Chain
Tension Adjustment.”)
4. Measure the distance again and tighten the
locknut (3) until the distance is between 8-1/2"
(216 mm) and 9-1/2" (241 mm).
5. If the extend chain clevis is in the last hole, the
locknut is fully threaded onto the clevis, and the
distance is less than 8-1/2" (216 mm); the chain may
be the incorrect size or over elongated and needs
replacing. (Refer to Section 3.4.1, a. “Inspection
Guidelines.”)
If the distance is greater than 9-1/2" (241 mm):
1. Loosen the retract chain locknut (3) on the bottom of
the outer boom one or two turns. A minimum of one
full thread on the clevis must protrude beyond the
elastic collar of the locknut.
2. Measure the distance and loosen the locknut (3)
until the distance is between 8-1/2" (216 mm) and
9-1/2" (241 mm) or until one full thread on the clevis
protrudes beyond the elastic collar of the locknut.
3. Verify that the extend chain clevis (4) is not mounted
in the first hole (5) in the anchor plate (6). If the
clevis can be moved to the next hole, do so and
check the chain tension. (Refer to Section 3.4.3,
“Boom Chain Tension Check,” and Section 3.4.4,
“Boom Chain Tension Adjustment.”)
4. Measure the distance again and loosen the locknut
(3) until the distance is between 8-1/2" (216 mm)
and 9-1/2" (241 mm).
MU0410
1
MU1410
2
3