I've replaced my Alternator bracket thinking that the high pitched sing above 3500 rpm was coming from a misaligned alteranator.

Now I'm wondering if its coming from the aluminum water pump and crank pulleys. Or is it the chrome pulley on my alternator ?

As long as I'm below 3500 rpm nice and quiet, but over it just starts to sing like a ringing sound.
I've made sure the belt is tight.
I've replaced the belt.
I've replaced the alt. brackets.

The condition was present from the first time I got the car together and running.

Any suggestions ?

Thad,

I had the same noise. Went to a deep groove underdrive GM pulley on the alternator. Still could get the noise at high RPM's. My guess is that you'll have to do what a guy at the track suggested to me,......take some emery cloth to your alternator pulley(sounds like the only steel one you're running if I read right). Cured my singing pulley problem:thumbsup: .

I've got the same problem, I'm trying to teach it to sing a new tune every week or so :D

Thad,

I had the same noise. Went to a deep groove underdrive GM pulley on the alternator. Still could get the noise at high RPM's. My guess is that you'll have to do what a guy at the track suggested to me,......take some emery cloth to your alternator pulley(sounds like the only steel one you're running if I read right). Cured my singing pulley problem:thumbsup: .

Yup, you read it right.
Thanks I'll try that.
It's just like me to spend a hundred bucks on a new belt and new billit brackets,
when I could've fixed the problem with a 50 cent piece of emery cloth. :clonk:

Mine was singing.. but poorly...
So I taught it to play the harmonica instead....