New noise since belt replacement.

[brorabongo]

Could my belts be making a noise? It sounds a bit like a turbo whine, but higher pitched. It changes with throttle use, not speed. The only thing thats different is the belts. The new ones are a "toothed V" shape while the old ones where a "solid v" shape.

[sajseven]

Sounds possible! Maybe the new shaped teeth could be causing a sort of wind resistance, therefore making the noise you describe. And because, when you rev the throttle the belt goes faster, the pitch/note will change. This would mean that you wouldn't have heard it before with the different shaped teeth. Or maybe I could be talking utter nonsense and I really should go fetch my coat.

[mister munkey]

Obvious things first matey.

Check nothings overtight. You should be able to twist the belts through 90 degrees. When I replaced my alternator I had the belts too tight, made a noise like that just before the bearings gave up.

[brorabongo]

Thanks guys

I check the tightness tomorrow, I've never heard of the 90deg method.

The belts were replaced as a precaution, as the old ones seem to be the originals, and there were threads hanging from them. I got the local friendly garage to do the belts as I had trouble getting the old'ens off

The alternator itself was ease to replace, and was done so because of noisy bearings? as described in this thread.

http://www.igmaynard.co.uk/bongo/forum/ ... =3&t=19069

Fault on old alternator caused by tight belts?

I'm now looking into refurbishing my old alt, anyone know a good place for bearings?

[dandywarhol]

I wouldn't use the 90 deg. method - that used to be the rule for cambelts.
Apply 10kg of force to th eback of the belt at the midway point between the water pump and the alternator on each individual belt and it should deflect 8 - 10mm. The A/C belt should deflect 11 - 12.5mm at the bottom run.

The A/C belt is probably less critical but if the waterpump/alternator belt is overtightened then you risk damaging the bearings

The only reason manufacturers now fit "toothed" belts to these pulleys is to allow them to work on tighter radii - the tooth bit doesn't drive anything.