what pops into my mind is short or worn brushes in the voltage
regulator/brush package unit in the back of the alternator.
Sometimes a new one of those will keep an alternator going a long time yet,
if it's the brushes that are warn.

you should also undo the alternator belt and check the bearings on the
alternator.
I find lots of alternators on 2.1's with loose or slightly worn bearings.

While doing that, also check the mounting bracket underneath the
alternator - or the nuts that secure it - it's a classic alternator failure
area on waterboxer engines. Doesn't happen too often, but when it does, you
want to catch it while it's just a matter of tightening things - left long
enough, you can even have broken off studs to deal with.

you should also just check charging voltage ( I do it at the battery, since
that's what needs to kept up to charge ) with a digital volt meter.
13.8 volts is 'par acceptable .............more than 13.8, up to 14.5 is
nice.
I check it at idle, then at idle with the lights on .  With lights on it
should  maintain the same charging voltage.
Rev it up too and check voltage at other rpm's too........but usually at a
good idle is fine for a charging voltage test.

got a rusty transmission ground strap perhaps ?
I always carry a spare alternator myself, like a good used one, and I have a
few I could sell if anyone wants a spare/back-up.
Scott
www.turbovans.com
Scott
www.turbovans.com
----- Original Message -----
From: "John Graham" <theklube@GMAIL.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Sunday, March 29, 2009 4:50 PM
Subject: 88 Vanagon alternator light problem

> Dear list,
>
> Well, I titled this 'alternator light problem' because that's what
> happened
> first.  Here's what has happened so far.
>
> I was coming back from the campout at Hunting Island when I noticed that
> my
> alternator light was on!  At first it was Oh Sh...t as I was driving along
> a
> two lane road with NO shoulder, but the temp guage was right where it
> should
> be and I had no other indications that anything was wrong.  I stopped for
> gas several miles later and found no missing belts or loose connections in
> the engine compartment. AND there appeared to be no reduction in battery
> power when I restarted, so I'm thinking something other than a gross
> failure
> of the charging system.
>
> While I was sitting in the gas station pondering my situation, the only
> thing that I noticed that was further info was that when I shifted the
> automatic from park down to drive and back, the alternator light flickered
> a
> little.  I tried clicking on the headlights and there was no flicker at
> all
> and the lights seemed to come on full.  So with my tank full of gas and
> only
> 3 more hours of interstate travel to get me back home, I set off.
>
> During my remaining trip, I noticed that the light would go off for long
> periods of time and then come back on.  It stayed mostly on during the
> trip.  I didn't try wiggling any of the instrument panel connections, but
> it
> occurred to me.
>
> I just went out and checked to see the specifics of details as I moved
> that
> auto trans lever.  The light is on full bright in Park and Neutral, but is
> slighty dimmer in Reverse and the Drive settings
>
> Any ideas of where I might look next?
>
> Thanks,
>
> John Graham
> 88 Westy
> Charlotte, NC
>
> --
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