Usage:
TH63 (3NN, 5WM) TH83 (3RN) TH103 (3PN) Telehandlers
Reference: Service Manual SENR5835, Service Manual Module SENR5843, Systems Operation Testing & Adjusting TH62, TH63, TH82 & TH83, "Boom Chains TH63 and TH83," Page 57.
Reference: Service Manual SENR1230, Service Manual Module SENR1239, Systems Operation Testing & Adjusting TH103, "Boom Chains," Page 52.
The boom extension and retraction chains must be cleaned, inspected, measured for wear every 3000 service hours or every two years. In severe operating conditions this service interval must be reduced.
Disassemble the chains from the boom. The disassembly and assembly procedures are detailed in forms SENR5846 and SENR1241.
Cleaning And Inspection
Use a suitable solvent degreaser to thoroughly clean the chains. Remove all traces of dirt and grease and lay the chains out on a clean bench for inspection.
Carefully inspect the full length of the chains for damage. In particular check the following for possible damage:
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- 1. Cracked or missing link plates.
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- 2. Elongated holes in link plates.
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- 3. Loose or worn pins with damaged heads.
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- 4. Rust or corrosion on link plates.
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- 5. Mark the most noticeably worn section of the chain, this will usually be near the center.
Extension Chain Wear Measurement
1. TH63 and TH83 Apply an end load of 3.19 kN (718.000 lb) to the extension chain to take up all clearances and wear.
TH103. Apply an end load of 3.93 kN (884 lb) to the extension chain to take up all clearances and wear.
2. Measure Dimension B between 16 pin centers of the most worn section of chain. If the measurement is greater than 388.6 mm (15.29 in) the chain must be replaced.
3. Measure Dimension A on all of the inner and outer plates between the same pin centers. If any measurement is less than 22.8 mm (.90 in) the chain must be replaced.
Wear Measurement Points-Extension and Retraction Chains.
Retraction Chain Wear Measurement
1. TH63 and TH83. Apply an end load of 1.42 kN (319.500 lb) to the retraction chain to take up all clearances and wear.
TH103. Apply an end load of 1.81 kN (407.250 lb) to the retraction chain to take up all clearances and wear.
2. Measure Dimension B between 21 pin centers of the most worn section of chain. If the measurement is greater than 388.6 mm (15.29 in), the chain must be replaced.
3. Measure Dimension A on all of the inner and outer plates between the same pin centers, if any measurement is less than 17.1 mm (.67 in) the chain must be replaced.
NOTE: It is not necessary to replace the chains in sets if only one chain is outside the tolerance, but if the boom is disassembled because of chain breakage, both chains must be replaced.
NOTE: The applied end loads specified during wear measurement are equal to 1% of the minimum breaking loads of the chains.
Lubrication
Spray the full length of each chain with Caterpillar Chain and Cable Lubrication on both sides. Ensure that the lubricant penetrates the working surfaces between the links and pins by articulating the chain as the spray is applied.
When the chains are assembled into the boom, lubricate the pins at the anchor points.
Ensure that the proper precautions are taken when using pressurized containers and solvents, and use proper protective equipment and clothing.