Alternator whine problem.

Sometimes you have to look at what makes the bearings fail, like an off balance rotor due to dirt or damage. Maybe even a bent shaft.

If you try to rebuild again, put the rotor on a set of V blocks resting in the new bearings and if you have a dial indicator, check the run out.

Also try rotating it in to different positions to se if it rolls back to the same position indicating it is heavy to one side.

Oh man... I can't believe I never thought of that. I happen to have a dial indicator but I'm not sure if I want to go through the trouble of pulling the alternator out, measuring, putting it in and then running out to get the parts...then pulling it again... etc. Getting to it is a pain in itself. I think I'll just grab one from the wreckers, play with it to make sure it's ok and take it from there. Once replaced, I'll play with the old one as per your suggestions to see what might have gone wrong.

Thanks for the input.

While you have the unit apart, change the brushes and polish out the slip rings.

Thanks Opie....

I did that the first time around. Got new brushes, diode pack, bearings, grease, etc, etc...

Just came back from a junk yard today. Picked one up for $45 and will try to put it in this weekend. I still need to replace the front control arms and wheel bearings... which brings me to another question but I think I'll just create a new thread for the benefit of others.

Oops! I assumed wrong!

Turns out the alternator is working fine, but was able to poke around with a stethoscope and found the idler wheel grinding and whining. Unlike the alternator, this at least will be a quick swap (hopefully).

Alex