Assuming that you've eliminated belt squealing, it may be on its last legs.
Mine started doing that and I took it to an alternator rebuild shop.  The
rebuilder said it was about to spin a bearing and wouldn't have gone another
300 miles (showed me the old bearing...he wasn't blowing smoke).

It was just under $100 for the rebuild, including sandblasting and repainting,
a couple of other internal parts, etc. and I had it back in 24 hrs.

When you hook it up again, make sure the belt tension isn't too strong or
you'll start wearing the bearings quickly again.

-Karl

> My 87 Westy has recently developed a squeaky noise that seems to be
> coming from the alternator.  It tends to make the noises only when it is
> cold.  The battery light on the dashboard remains lit until the accelator
> is depressed.  Does this sound like the beginning of an alternator going
> bad?

Karl and Kristina Bloss, Trexlertown, PA
'87 Westfalia Weekender  "Beverley" - 196K miles
http://www.enter.net/~bloss/vw/
PA/NJ Vanagon owner's mailing list: http://www.enter.net/~bloss/vw/pavanagon/