'Whistly' alternator...

[wasted]

Ok, since I replaced the timing belt on Igor (in the process buggering up the timing, but that's another issue) the alternator has been making a really, really irritating noise. When sat at idle, there's a continuous whistling sound coming from it - it varies, and sounds very much like an oscillating squeak. As the car warms up, it very gradually goes away - but not totally.

This makes me think that it's something to do with the bearings and/or the axle of the alternator being worn. I've tried loosening the alternator belt, but that just makes it squeal horribly, so it seems to be set to the right tension.

Any ideas? New alternator?

[ianaudia4]

I have a spare alternator 90amp, Works and it good nick.

[wasted]

Hmm, you tempt me, sirrah.

Want to PM me a price including postage?

[markh]

If is definately the alternator ? Have you run it with the alternator belt off to see if the noise stops ? If the timing belt is over tensioned it will make a whistling noise.

[wasted]

If is definately the alternator ? Have you run it with the alternator belt off to see if the noise stops ? If the timing belt is over tensioned it will make a whistling noise.

Yeah, definitely the alternator - I took the belt off a while back, and no noise. Also, I hit the alternator axle gently with a mallet to see if I could ease it off, and it stopped the noise temporarily.

Ian - I've PMed you back, cheers for the info :)

[buggerrit]

WD40 is your friend - a good dose will quieten it down.
Probably get shot down for the answer, but I've been
doing that for years on all sorts of belt driven things!

[wasted]

I might just give that a go :) squirt it in through the axle opening?

[buggerrit]

Yep, I usually give em a squirt either end, ie behind pulley and into split rings/
commutator thingamygiggin. Works on noisy belts as well, not slipping ones tho'

[Nate]

WD40 is your friend - a good dose will quieten it down.
Probably get shot down for the answer, but I've been
doing that for years on all sorts of belt driven things!

WD40 is basically evil. i can't stress this enough. covering your engine bay in it will just make dirt stick to it and make it a horrible place to work. it rots rubber and the dirt sticking to it promotes rust.

assuming that the noise goes when you take the alt belt off, spin the alternator y hand, check that it is smooth and quiet. if it is, try either tightening the belt or fitting a new belt.