To drive the belts
They snap to the max.
I'm assuming you mean a pulley, which is what the belts run on. If so, depending on which pulley the bearings could be bad or if it is the crankshaft pulley (big pulley near the bottom) the rubber could be getting bad.
Put the new fan belts around the fan pulleys. Slide the top tensioner pulley upward. Tighten down the tensioner pulley when you have achieved the proper fan belt tension.
Large drive pulley, small driven pulley = faster rotation but less torque. Small drive pulley, large driven pulley = slower rotation but more torque.
bottom of engine where belts go
remove all belts,tensioners etc, remove pulley bolt, use HARMONIC BALENCER PULLEY to remove - DO NOT USE NORMAL PULLEY REMOVER - must be pulled from center of pulley not from outer edge
Lift car on jack stands, remove right wheel for better access,remove any belts, remove pulley bolt, then use a pulley remover to remove pulley, carefully pry out old seal thebn tap in new seal with mallet or plastic hammer, if pulley has ridges on it you may have to replace pulley or you might still have leaks. reinstall pulley,bolt, belts and wheel. Good Luck.
First of all, they are the same as the fan belts on any other car. The fan belt(s) are the serpentine drive belt(s) that turn your fan and other accessories (like alternator, compressor, power steering) They are often referred to as serpentine belts, drive belts, and accessory drive belts. The are located on the outside of your engine, driven by the main pulley (crankshaft pulley). R. Mesyef
It could be the bearing in your tension pulley.
remove the varable speed pulley-replace both belts re-install varable speed pulley--your done.
The 1989 Toyota Corolla serpentine belt can be tightened or loosen with the tensioner pulley. Pry to the left on the tensioner pulley until the belt is tight. Tighten the tensioner pulley.