SkyTrak 8042 Service Manual - Manual (Page 197)

Boom
3.136 Model 8042, 10042, 10054 Legacy Rev. 03/04
a. Component/Assembly Verification
The secondary intermediate (1) to primary
intermediate (2) 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 secondary
intermediate and primary intermediate boom top plates.
The distance (3) should be at least 8.5" (216 mm) and not
greater than 11" (279 mm) with the boom fully retracted
and the chains properly tensioned. A distance of less
than 8.5" (216 mm) could result in interference and cause
damage to boom components.
If the distance is less than 8.5" (216 mm) or greater than
11" (279 mm):
1. Verify that the retract chain clevis (4) is not mounted
in the last hole (5) in the anchor plate (6) .
2. Make sure that the chain system is properly
tensioned. Refer to Section 3.7.3, “Boom Chain
Tension Check,” and Section 3.7.4, “Intermediate
Boom Chains Tension Adjustment.”
3. To increase the separation distance: Loosen the
retract chain locknut (7) on the bottom of the outer
boom one or two turns and tighten the two extend
chain locknuts (8) equally the same number of turns.
A minimum of one full thread on the clevis must
protrude beyond the elastic collar of the locknut.
4. To decrease the separation distance: Loosen the
extend chain locknuts (8) at the rear of boom equally
one or two turns and tighten the retract chain
locknut (7) the same number of turns. A minimum of
one full thread on the clevis must protrude beyond
the elastic collar of the locknut.
Note: If the secondary intermediate to primary
intermediate boom separation distance cannot be
achieved, contact the local Sky Trak distributor or the
JLG Service Department at 1-877-554-5438 or
1-717-485-6657.
OH2861
1
2
3
MA9450
4
5
6
OA0512
7
MH1780
8