I can't seem to get the fan belts guiet, I have tightened, loosened and done it over again. New belts, on clean pulleys, maybe too clean, any ideas, thoughts. Is there a spray that might work? This is a newly rebuilt 396 and only out for test spins so far. Belts don't squeal in shop while engine idles, or revved up, so far only when under load and speed is increased. Thanks for your thoughts and response.....

I thought silicone was the ticket...

Belts WILL NOT squeel unless something is WRONG. Belt dressing/silicone/panther **** is just a crutch.

First guess: The pulley(s) are worn. They should have a definite "V" shape where the belt rides, with straight, flat sides at the appropriate angle. If the pulley(s) are worn to a "U" shape, you'll spend the rest of your life trying to stop the squeel.

Second guess: Wrong width belt for the pulley system, or a mis-matched pulley in the set.

Either way, the belt is riding on the bottom face, not on the angled sides. Does the underside of your belt show wear?

I had that problem with new pulley's and belts ( that were the correct ones ). I used some crocus cloth to take the 'polish' off the sides of the pulley grooves and it went away.

I've got same problem. New pulleys and belts but is intermittentmost of the time. I will try the sanding with crocus next. Thanks--RWS

Thanks for the responses and the information. I will definitely check pulleys for wear and also the belts to be sure they are correct and riding in the grooves correctly. If all appears right will try the crocus cloth, a bit of belt dressing and see what happens....thanks again for ideas.

I've been having the same problem...I think it might be a worn pully. What is crocus cloth and where can I find it?

Crocus cloth or emery cloth about the same thing. You can get it at most places selling sand paper products, paint supply houses, Home Depot, etc...

John,
I just had this going on last week and it ended up being the battery was to small to handle what I needed. What I mean is when the car stereo and amps where on, the alternator could not keep up and the belts squealed something fierce. I discovered this buy removing the alternator belt and restarting the car, no squeal. I tried everything up to that point, belt dressing , loosening, tightening belts and brackets, but after I installed the optima yellow top deep cycle battery, it was gone . The guy at the parts store said it's pretty common when trying to run convertible tops, stereo's etc. Might not be your problem, but I thought I would throw it out there.

just my 2 cents

later, graemlins/thumbsup.gif
Tom

All pulleys should be offset just a hair or two to prevent belt squeel.

Pulleys in perfect alignment are also an invitation to throwing belts off.