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Discussion Starter · #1 ·
I am on the verge of giving up this wonderful hobby that I used to enjoy. So that this post is not twelve paragraphs long, I'll get to the point and skip the six other things that have gone wrong and aren't related to this problem.

I replaced my stock alternator with a Powermaster 100. Over the course of today, and switching out the pulleys and alternator fans in various combinations, and breaking three alternator belts, I'm about to lose my mind.

Here are the symptoms. At idle, the alternator is charging and everything seems fine. If I get the RPM's up to about 2000 and above, the belt starts to squeal and (on the most recent belt) little pieces of rubber start coming off of the belt. With the earlier belts, I couldn't go more than a mile or two before the belts finally snapped.

Any idea what the *^%&! is going on? Is my new alternator bad?

Any help would be appreciated.
 

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This may be a rather simple question, but have you ensure that the new alt puts the pulley in exactly the same posision? If you are a little 'off' and it angles the belt, your belts with start to wear on the outer edge first and eventually give way. Depending on how far out you are will depend on how fast the belts wear.
 

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The only two things that I can think of are:
1 Does the V in the belt match the pully's V correctly?

2 Are you sure that the alignment between the pullys is true? Hold a straight-edge between them to be sure.

I know those are obvious but it doesn't take much to eat a belt if somethings even a little bit tweaked. I've suffered that frustration before. Good luck!
 

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Think the problem is in the belt size. Try one a bit large widthwise. Use a Gates brandd for sure. Closely look at the grooves on the pully on the crank shaft andd the alt, should look the same. When tightening thee belt leave just a little play in it betweeen thee pullys, like half inch or little less. Don't over tighten, will wear alt. bearing quickly. Squealing means belt is slipping, not tight enough. Use a solid belt not a serated one. serated is little notchs on the backside of the belt where it rides in pully..
 

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Discussion Starter · #5 ·
Upon close inspection, it looked like my alternator pulley was a little bit out of alignment with the crank pulley. I shimmed the mounting brackets and there is better line up. It still squeaks with a 13 mm belt. A 15 mm belt and my original alternator appears to work fine (30 mile test drive with no incident). The 15 mm belt with my new alternator still squeals about 2000 rpm, but not as bad as prior to shimming the brackets.

As suggested, I'll try a wider belt (17 mm I think is the next size) for the new alternator. By the way, for those wondering, I'm replacing the original alternator to get more amperage for my newly installed electric fan. Otherwise I'd probably settle for the original alternator and forego this latest aggravation.

Thanks again for all of the help.
 
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