Date: Tue, 04 Feb 1997 21:34:35 -0800
Sender: Vanagon Mailing List <vanagon@vanagon.com>
From: Jim Thompson <jim96003@c-zone.net>
Subject: Re: alternator blues
Tonya Pope wrote:
>
> Hi all--
>
> Well it would appear that my previous post about the freaky alt. and OXS
> lights was indeed due to my alternator. It is still working, but not
> getting the battery a good charging. I have not been back there to look
> at it yet. Kind souls have pointed out that it could just be a corroded
> connection (I hope!)
>
> Thanks so much everyone for all your help!
> Tonya
> 87 Vanagon GL Wolfs
> 74 S. Beetle
Hi Tonya -
Saw your post and thought I could offer a few tips when checking the
alternator:
1. Before removing or checking the wire harness at the alternator (or the
alternator itself) disconnect the battery ground strap to prevent sparks
and shorts.
2. I know you've probably heard this before, but corrosion could be the
culprit, especially where the thick red wire from the battery connects to
the B+ stud on the alternator. Remove it and inspect for corrosion -
clean it if its possible then re-connect to the alternator. If the
corrosion looks like it is "infecting" (best word I could find) where the
ring terminal is crimped onto the wire, you may have to replace the ring
terminal itself - there should be plenty of wire to cut, strip and
re-crimp a new terminal onto it. After reconnecting, put a dab of
Vaseline on the stud and ring terminal to help prevent the corrosion.
3. Recently, on my 80 Vanagon, I was having charging problems and traced
it to the brush assembly which is part of the voltage regulator (on the
back of the alternator - towards FRONT of Van) in where the brushes were
very very worn down. My regulator happens to be the same as your 87 (I
have an updated alternator on my van) and Bentley says when they're new,
they should be about 13mm (19/32") protruding from the brush holder with
a wear limit of 5mm (7/32") protruding from the brush holder. Mine were
less than 3mm! Replaced it and it definitely helped the charging system.
Note: If the end of the brushes are deeply pitted or grooved, forget
replacing the regulator, get another alternator, because the slip
ring/commutator they're riding on is severly grooved and/or worn and
you'll wear the brushes out real quick!
4. Another crazy problem indicative of Vanagons - they have the worst
grounding for the battery I've ever seen - A stud (or bolt?) protrudes
from the base of the battery box for the strap to attach to with a
flimsy, thin washer. And the hidden head of the bolt underneath didn't
feel like it makes the greatest ground contact in the world either. I
would occasionally lose all power and when wiggling the ground strap it
would suddnly come back. Drove me crazy! Got a thicker and wider washer
(8mm ID) to make better contact with the stud/bolt and the metal of the
battery box floor (scraped the paint away too). When I re-attached the
nut, I alternatively tightened, then loosened the nut a few times, then
tightened down firmly to make as good a contact as possible. Haven't had
a problem since.
My 2cents worth
Jim