COVER 3200348 - Caterpillar

Check Condition
Park the machine on level ground. Fully retract the boom and lower the boom.
Remove the cover from the rear of the chassis.
A limited inspection of the chains can be made through the rear of the boom. The boom extension chain can be inspected by fully extending the boom and looking on top of the intermediate section. If the chains are corroded, the chains must be removed from the boom for cleaning and a full inspection. If the chains require lubricant, the chains must be removed from the boom for cleaning and a full inspection. Refer to the Hydraulic System Systems Operation, Testing and Adjusting, "Boom Chain - Clean/Inspect/Lubricate" or consult your Caterpillar dealer.
Install the cover on the rear of the boom.Check and Adjust the Chain Tension
Slacken the extension chain and the retraction chain slightly. Raise the boom to the maximum angle and retract the boom. This ensures that all sections of the boom are fully retracted. If the retraction chain requires adjustment and the boom is retracted in a lowered position, all the sections will not fully retract.
The boom can fall if a control is moved or if a hydraulic component fails. This can cause personal injury or death. Support the boom with stands. Do not rely on the cylinder to hold the boom up.
Illustration 1 g00836123
Lower the boom to the horizontal position and install a suitable stand under the first section in order to prevent the boom from falling unexpectedly. To properly support the boom, use the following tools:
Table 1
Required Tools    
Part Number    Description    Quantity    
8S-7641     Tube     1    
4C-6486     Stand     1    
8S-7615     Pin     1    
8S-7625     Collar     1    
8S-8048     Saddle     1    
Lower the boom to a position just above the stand and stop the engine.
Illustration 2 g01109371
Illustration 3 g01109372
Set the minimum distance to 224 mm (8.8 inch) between boom section 2 and boom section 3. The maximum allowable distance is 234 mm (9.2 inch). Tighten extension chain (1) in order to move section 3 outward. Tighten retraction chain (2) in order to move section 3 inward. If the distance is significantly more than 224 mm (8.8 inch), slacken both chains and refer to Step 1.
After setting the distance to the required tolerance, tighten the extension chain to 20 N m (15 lb ft).
Tighten the retraction chain to 18 N m (13 lb ft).
Tighten the extension chain to 105 5 N m (77 4 lb ft).
Tighten the retraction chain to 70 5 N m