Lull 944E-42 Service Manual - Manual (Page 55)

3-25 944E-42
Boom
5. Drooping chain, or jerky
boom extend or retract
functions.
1. Chain(s) tension not properly
adjusted.
1. Adjust chain(s).
2. Chain(s) stretched or binding. 2. Replace chains as needed.
Refer to Section 3.4, “Boom
Extend and Retract Chains.”
3. Wear pads loose, contaminated,
excessively worn or damaged.
3. Replace wear pad. Refer to
Section 3.5.2, “Wear Pad
Installation and Lubrication.”
4. Contaminated, corroded or
rusted wear pad sliding
surfaces.
4. Remove contamination and/or
corrosion from wear pad sliding
surfaces and lubricate. If the
surfaces cannot be reconditioned,
replace the boom section(s).
5. Extend/Retract hydraulic system
not operating properly.
5. Refer to Section 8.4, “Hydraulic
Circuits.”
6. Damaged boom section. 6. Replace the damaged boom
section. Refer to Section 3.3,
“Boom Assembly Maintenance.”
6. Boom will not raise or lower. 1. Broken hydraulic hoses or tubes
and/or connection leaks.
1. Locate break, replace hose(s)
or tube(s), tighten connections.
2. Lift/Lower hydraulic system not
operating properly.
2. Refer to Section 8.4, “Hydraulic
Circuits.”
3. Faulty Lift cylinder. 3. Repair cylinder. Refer toSection
8.7.17, “Accumulator Charge
Troubleshooting.”
4. Seized boom pivot pin bushing. 4. Replace bushing.
7. Excessive Lift/Lower cylinder
pivot pin noise and/or wear.
1. Insufficient lubrication. 1. Lubricate at regular intervals.
Refer to Section 2.5, “Service
and Maintenance Schedules.”
Replace worn pins as needed.
Refer to Section 8.7.17,
“Accumulator Charge
Troubleshooting.”
2. Worn self-aligning bushing(s). 2. Replace bushing(s) and
lubricate at regular intervals.
Refer to Section 2.6,
“Lubrication Schedules.”
Boom Troubleshooting (Continued)
Problem Cause Remedy