LINE ASSEM. (no. 6) 8N3456 - Caterpillar

Inspection
Inspect the alternator belt and the fan drive belts for wear and for cracking. Replace the belts if the belts are not in good condition.Check the belt tension according to the information in the Service Manual, "Specifications".Slippage of loose belts can reduce the efficiency of the driven components. Vibration of loose belts can cause unnecessary wear on the following components:
Belts
Pulleys
BearingsIf the belts are too tight, unnecessary stress is placed on the components. Unnecessary stress reduces the service life of the components.Adjusting the Alternator Belt
Illustration 1 g01092641
Typical alternator
(1) Mounting bolt
(2) Adjusting nuts
(3) Mounting bolt
Loosen mounting bolt (1), adjusting nuts (2) and mounting bolt (3).
Turn adjusting nuts (2) to increase or decrease the drive belt tension.
Tighten adjusting nuts (2). Tighten mounting bolt (3). Tighten mounting bolt (1). For the proper torque, see the Service Manual, "Specifications" module.
Reinstall the drive belt guard.If new drive belts are installed, check the drive belt tension again after 30 minutes of engine operation at the rated rpm.Fan Drive Belt
The fan drive utilizes an automatic tensioning idler pulley system.Replacement
For applications that require multiple drive belts, replace the drive belts in matched sets. Replacing one drive belt of a matched set will cause the new drive belt to carry more load because the older drive belts are stretched. The additional load on the new drive belt could cause the new drive belt to fail.