My fan belt squeals bad at about 3500 rpm! It's okay under 3500 but as soon as it reaches 3500 it is a constant squeal. Has done this every since I put the new crate moter in the car. Changed the belt and it worked for a couple of days but then back again. Bought a Gates belt as someone told me it was because of cheap belt. Same thing! Any ideas or suggestions?

Steve

Steve,

I've found that a noisy belt is usually caused by the tension not being correct, which allows some slippage, which causes the belt to get glazed, which causes it to lose its grip, ... and so it snowballs. But I've had other things happen which have contributed to belt noise, like a bad idler pulley on my truck's serpentine belt, or an altenator that was failing and not spinning as freely as it should. One thing to check for as well is that all the pulleys are in alignment (in the same plane, as it were). If one is too far out of plane with the others that would cause some sideways flexing on the belt which would contribute to the glazing, which...

I've tried different belt conditioner/treatment sprays with only short term results. Bottom line, once you've discovered the problem and before you put on the new belt - clean up all the pulleys as they most likely will have some build up of old belt residue on them.

Jim O - Thanks for the reply! I too, have tried belt dressing and even used bar soap at the suggestion of a friend. Temporary fix! The pulleys appear to be lined up, the alternator is new. The belt is tight but I'll mess with the tension some. Someone suggested that I try to find a narrower belt. What do you think?

What pulleys changed when you changed to the crate motor? You may want to look at any new pulleys that you may have changed to see if they have the same v-belt angle as the old ones had. If the angle is different you won't have complete contact between the grove and the belt...which would work at low rpms but may slip at higher rpms.

Good luck,

|UPDATED|11/12/2002 12:30:01 PM|/UPDATED|

Thanks. I used the same pulleys from the 427 but I will check that as soon as I get home tonight. I did have a whirring noise with the 427 now that I think about it. Thanks again!