Alternator pulley

[Yellow20thAEGti 10+ year member]

I just finished installing my HO alternator. When I crank my car up I notice that the belt squeal is terrible. Could this be due to the smaller pulley on the new alt? If so, would there be any volt loss going back to the stock pulley?

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[Pioneer~Saturn 5,000+ posts]

If it's a direct replacement and youre using the same belt with a smaller pulley, I would try and find a slightly smaller belt. Do you notice it being a bit more loose?

 

[dman4486 5,000+ posts]

did you change anything other than the alt?

 

[Yellow20thAEGti 10+ year member]

Just a little, but not that much. I did notice that the belt does come extremely close to touching where the tensioner pushes on the belt above the AC condenser. Because of this I think I may have to change the pulley. //content.invisioncic.com/y282845/emoticons/frown.gif.a3531fa0534503350665a1e957861287.gif

 

[Yellow20thAEGti 10+ year member]

did you change anything other than the alt?

Nope

 

[Yellow20thAEGti 10+ year member]

I would prefer to change pulleys if this is the problem because I dont have a way of going to get a belt atm.

 

[dman4486 5,000+ posts]

then switch the pulley and see if it solves it

 

[audioarsonal 10+ year member]

Switching th pulley will effect idle output.You need a smaller pulley on most HO alts.

Normally when switching out your alt you will need to get a belt 1/2" smaller then the current one.

 

[Pioneer~Saturn 5,000+ posts]

If youre talking about the tensioner moving more inwards (the way it's pushing)...then I would try a smaller belt to bring it in and see if that solves the problem...dont just go and change the pulley before trying some simple and pretty cheap steps like another belt.

I went and got a slightly smaller belt after my 2nd alt went in and it solved everything.

^x2 audioarsonal

 

[Yellow20thAEGti 10+ year member]

Alright....I appreciate all the help. I guess changing the belt also saves me time from having to unbolting everything again.

 

[Yellow20thAEGti 10+ year member]

Update not anyone cares....I have to change the pulley because nobody carries smaller belts for my car. It is double sided. The dealer did not even carry one.

 

[andrewmoore13 10+ year member]

i find it interesting... did it work?

 

[Yellow20thAEGti 10+ year member]

i find it interesting... did it work?

I haven't taken the alternator to get the pulley removed. Seems that everything on Volkswagens require a special tool to be removed. Will have an update later this evening.

Also since it was stated earlier that I would lose output on idle, does anyone know about how much? Its a 200amp DC power alternator.

 

[InhumanAcura 5,000+ posts]

you remove the pulley and your ho alt isnt going to be as ho as it was...think about it, the alt spins more with the smaller pulley, generating more power. you put a smaller pulley on, and youre going to decrease the amount of power generated. have you tried belt dressing?

 

[audioarsonal 10+ year member]

^^I think you mean larger pulley he will lose output.

OP idle output is directly related to the size of the pulley.And most HO alts don't have output until 2400rpm alt speed which equates to 3-4 times the engine rpm.If your at 4 times the engine rpm now and you change to a larger pulley you would drop to say 3 times the engine rpm.