Get a piece of garden hose about 18 inches long and use this as a stethoscope to listen to the various bits of the engine and the suspect areas while the engine is running - but be careful not to get bits of yourself trapped in any moving parts.
A quick way of checking the alternator - as long as the belt does not drive anything else - is simply remove the belt - spin the alternator round by hand, you will soon see, or rather hear, if that's the source. Then start the engine - if the noise has gone, and the alternator was running silently and freely, it's the belt!
My wife's old polo use to make a bag of nails noise if the alternator belt got a bit manky - they did seem to disintegrate fast!
Hi folks,
>
> my 83 vw golf has developed a moaning sound which has increased in
> intensity now.i cant pin point it but it seems to be coming from the
> region of the alternator/distributor/water pump and possibly intake
> manifold (but i couldnt get ear close enough to check the last one).
> the alternator belt is quite loose and i got another one which i will
> change next week.
>
> the sound is sort of like a cat moaning or a sound ghosts are supposed
> to make to haunt. it happens loudest after you accelerate and you let
> go of the gas like decelleration of a turbo only i dont have one. >
> i am not sure if it is an air leak problem or a bearings (main engine
> or distributor bearings) problem.
>
> any ideas what is wrong or how to find it?
>
> thanks,
> Sam