PLATE AS 3694677 - Caterpillar

Inspect and Adjust or Replace
Inspect drive belts for wear and replace if they show signs of wear. Replace the belts in sets only, if one or more belts are worn or damaged. If belts are too loose, they vibrate enough to cause unnecessary wear on the belts and pulleys.If belts are too tight, unnecessary stresses are placed upon the pulley bearings and belts which might shorten the life of both.
Illustration 971. Inspect the condition and adjustment of alternator and fan drive belts.
Illustration 982. To check the belt tensions, apply 45N (10 lb) of force midway between the pulleys. Correctly adjusted belts will deflect approximately 10 mm (0.375 in).Adjust Belts
Illustration 991. To adjust drive belts, loosen alternator pivot fasteners (2) and adjusting bracket fasteners (1).2. Adjust the alternator position in or out to obtain the correct adjustment. Tighten fasteners (1) and (2).3. Check belt tension again to make sure the tension is correct.4. If new belts are installed, check belt adjustment again after 20 service hours of engine operation.