I have a 82 Ta stock everything, the alternator has been changed to a stock replacement type from autozone.

It has broken fan belts twice now and I never hear any noise or know when it's happening.
I buy the belts the books say it takes from AZ.
If I have much slack it slips and squeals but if i adjust it fairly tight then the squeal goes away but the belt only lasts a few months till it brakes again.

what is wrong and what can I do to fix it?

 

Belt part # should end in 450. If so, it's OK.

With the front 2 belts off, check the water pump and the smog pump and make sure they turn freely by hand.

 

probably a worn alternator pulley is the cause-pulley won't grip the belt untill it is tensioned really tight.Using good belts?-not cheapies from china,india,korea,etc I had alternator belt breakage problems with my '82,but only when revved to over 5500 rpm-sometimes when revved over 5500 the belt would flip over in the pulley grooves and break.fixed the problem with a '69z28 style deep groove alternator pulley.

 

It's a new alternator and I have no smog pump and the water pump is new also and everything turns good.

I already threw the belt away but I don't think it ended with number 450.
It was the belt for a ac car like mine.
does it matter if the car has the bigger stock 70 amp alternator?

I might have to go to another store and not AZ this time.

 

Part # is 7450 or 15450 depending on brand. (7/16" or 15/32" wide depending on brand, 45.0" long)

Get a Dayco, Gates, or Goodyear in one of those part #s.

 

To me , the key to your problem is in this sentence . My bet is that your pulleys are "glazed" from the belt slipping previously , and now that the pulleys ARE glazed , it takes excessive belt tension to overcome the slipping . It is this overtension that is shredding your belts so quickly . What you need to do is to clean the shiny glaze off of the pulleys so that the belt can be run at it's normal , proper tension .

Remove the belt and take a wirewheel mounted in a 3/8" electric handdrill and clean all that shiny glaze off of any and all pulleys that have it . Replace your belt cause it's probablly glazed too , install the new belt at the proper tension , and I'll bet ya see a big difference ........

 

This is a short read:

www.gates.com/cool/images/V-Belt_Failure[1].pdf

 

your link didn't work for me Paulo.

I found the sleeve the belt came in and the number is 15445

made in Korea

What does the glaze look like on the pulley, I don't really see anything odd.

 

445 should work OK too; might be a bit harder to get on the first time when new since it's a half-inch shorter, but otherwise, fine.

"Glaze" looks like the pulley is polished. Hard for a belt to grip if the surface is too smooth. You can just take a Roloc pad or something, and bust the shine off th epulley groove surfaces.

 

445 is good- i have that on mine,with 85a 15si alternator and the slightly larger '69 z pulley i am at about 1/3 of adjustment range with a couple years on the belt.

 

I tried cleaning the pulleys but nothing really came off, put the new Dayco topcog belt on and set it pretty close to adjusted right but not tight like before and it has a slight slip to it again.

 

Check the alignment, it's hard to spot a belt slightly out of alignment. use a flash light and look at the surfaces, like sighting a gun. Look at all the pulleys that are running that belt. Now lets take the crank shaft pulley, if you were to lay a straight edge across the surface it should be pointing dead even to a point in front of the alternator. all the pulleys have to point perfect or it will cause wear issues and can throw off the belts. I see belt alignment problems often.

Dave