fan belt squeaks

[Steve Gallegos]

The fan belt around the pulley on the crank shaft is making a terrible noise. When I spay WD-40 on the pulley the noise goes away for about 2 minutes, then comes back. I replaced the belt last for the same thing, I can't believe the belt is bad. Could it be that the belt is too big and after a while it stretches. Should I use a smaller belt?. I have an auto tension pulley to keep the belt tight, but maybe it's at its limit?

[mtrain2000]

I've got two Nissan Altima's doing the same damned thing.

One has a brand new Gates belt, and new tensioner, the other has a new parts house brand belt, and both cars have squealing belts.

I took them both off, and sprayed belt dressing on them, and it did get them quite for a little while, but after a minute or two, here they go again.

I tried hitting them with a bar of soap, and also a candle. Same thing, they quite down, then start up again. After driving for a while they shut the Hell up, but when their cold they're load.

I'm going to try a smaller belt sometimes next week, and see if that will quiet them down..............good luck.

[Steve Gallegos]

On other thing, the pulley has grooves in it going around the pulley. The belt has matching grooves. Should I get a belt that has bumps or ridges across the belt to better hold on to the pulleys?

[DanEC]

I would check your pulley alignment to make sure they are in line with each other. Often you can do that by simply laying a straight edge on the outside of one, extending towards the other pulley and see if the grooves appear to be in line between them. And check that the belt is not too narrow and sitting in the very bottom of the pulley. Other than that - time for a new belt.

[DanEC]

Originally Posted by Steve Gallegos

On other thing, the pulley has grooves in it going around the pulley. The belt has matching grooves. Should I get a belt that has bumps or ridges across the belt to better hold on to the pulleys?

Ohh - this is a serpentine type belt - you can ignore my earlier post.

Sounds odd that both the pulleys and the belts have grooves. You may have hit on something there.

[bingo2]

1. Remove belt.
2. Take some medium Scotch Brite and rough up the pulley(s)/belt mating surface.
3. Clean the pulley(s) and groove surfaces with brake cleaner or acetone.
4. Buy a Goodyear Gatorback belt.

[Tommy]

No expert here, but wouldn't spraying WD40 on a slipping belt make it slip even more?

[BAsque1]

Be judicious with the belt dressing I have seen a belt literally jumped off the pulley. It looks like the grooves must be engaged by those on the pulley.

[cycleguy55]

Belts squeal because they're slipping, so adding anything like WD-40, soap or candle wax will only make that worse. It may help very temporarily by reducing the friction enough to stop the squeal but, once past that, the residual amount will make the belt slip even more. I would replace any belt which has been contaminated by any of these products.

I would second the recommendations of bingo2. For v-belt pulleys (not serpentine), I would also add that replacing steel pulleys with aluminum ones would help, as the aluminum ones tend to grip better. If you have a serpentine, multi-ribbed belt and pulley system those pulleys should already be aluminum.

[Steve Gallegos]

Thanks for the info. The pulley on the cam in groved and I think is aluminum, the whole bracket system is made by Billet corp, as for the belt I don't think the Gaterback type comes in a groved type, I have only seen it in the ribbed belt.