Lull 944E-42 Service Manual - Manual (Page 50)

Boom
3-20 944E-42
3.4.7 Extend Chains Removal and
Replacement
1. Park the machine on level ground. Place the
transmission control lever in (N) NEUTRAL, engage
the parking brake switch, level the boom and shut
the engine OFF.
2. Place a Do Not Operate Tag on both the ignition key
switch and the steering wheel, stating that the
machine should not be operated.
3. Properly disconnect the battery.
4. Remove the boom rear cover.
5. At the rear of the third boom section, disconnect the
retract chain (5) from the anchor link (6).
6. Remove the clevis pin (7) from the extend chain yoke
at the front of the boom. Lay the chain assembly flat
against the third boom section.
Note: Chains and clevis’ are wear items and experience
the same stress. DO NOT attempt to repair a chain.
Replace a stretched or damaged chain with a new part.
Always replace both the chain and the clevis’.
7. Remove the extend chain sheave (8).
8. Attach one end of a string or wire to the extend chain
yoke. The string or wire must be long enough to pull
the extend chain through the boom.
9. Pull the extend chain out through the rear of the
boom. Remove the wire from the clevis, but not from
inside the boom.
10. Inspect wear and condition of the booms, chains,
clevis’, chain sheaves, extend/retract cylinder, chain
rods, clevis anchors and all mounting hardware.
Replace any worn or damaged parts. DO NOT
attempt to make any repairs to the chain.
11. Attach the wire to the new extend chain and pull it
through the boom between the third and second
boom section.
12. At the front of the second boom section, coat the
sheave pin and bore with anti-seize compound.
Install the sheave. Loctite
® 242™ and torque the
capscrew to 90-162 lb-ft (123-220 Nm).
13. If needed, pull the boom out slightly to align the
extend chain yoke with the sheave. Route the extend
chain around the sheave on the second boom
section. Coat the clevis pin and bore hole with anti-
seize compound. Install the extend chain yoke to the
first boom section.
14. At the rear of the boom, install the retract chain to
the anchor link. Loctite ® 242™ and torque to 37-66
lb-ft (50-90 Nm).
15. Check and adjust boom chain tension. Refer to
Section 3.4.5, “Boom Chain Tension Check.”
16. Install the rear boom cover.
17. Properly connect the battery.
3.4.8 Retract Chain Removal and
Replacement
1. Park the machine on level ground. Place the
transmission control lever in (N) NEUTRAL, engage
the parking brake switch, level the boom and shut
the engine OFF.
2. Place a Do Not Operate Tag on both the ignition key
switch and the steering wheel, stating that the
machine should not be operated.
3. Properly disconnect the battery.
4. Remove the boom rear cover.
MU0261
5
6
MU0211
7
8