Date: Mon, 8 May 2000 18:22:09 -0700
Reply-To: Doktor Tim <doktortim@ROCKISLAND.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Doktor Tim <doktortim@ROCKISLAND.COM>
Subject: Re: 84 westy alternator light flickers(longish)
In-Reply-To: <60F1FEB31CA3D211A1B60008C7A45F4302489675@blaze.bcsc.GOV.BC .CA>
Content-Type: text/plain; charset="us-ascii"
At 03:50 PM 05/08/2000 -0700, you wrote:
>Hello Volks,
>
>Here's the deal, Yesterday when going for a relaxing Sunday drive, about 10
>km in, the alternator light in the dash comes on. EEEk. Now, this light has
>ALWAYS come on when the engine turns over, then when it is running a "blip"
>of the throttle and its gone. I read some discussion lately about how this
>is not normal, I though PPff, whatever, it has always done this and never
>posed a problem to date.
Typical. A lot of them do. A lot of them don't. Sometimes this can be
improved with a new bulb, but it ain't a problem if you just rev it once to
excite the alturnator and it goes off every time.
There has never been a problem with cranking
>power. I also have an auxiliary Optima that is connected to the LED. This
>light has recently been in the yellow unless the engine is running,
>alternator charging. In the not to distant past this light was always in
>the green, unless there was a power draw. Hmmm . I believe the consensus was
>that this was normal, to be in the yellow.?
>
Could be a sign of weakness. Make sure the batteries are clean and
terminals and ground straps are Bristol.
>
> The alternator light seams to come on and go off intermittently, and around
>4000rpm it also goes out. The belts are tight, with the engine running, the
>LED for the auxiliary battery is in the green. So I assume the alternator
>is functioning. Excuse my ignorance here, I am no mechanic. Is there a way
>to test the alternator.,
Hook a digital multimeter up to the battery terminals. (Do not use a cheap
analog or digital drug store peg hook meter. Bad data is worse than no data
if you think it's good data. Beleive me, it is the road to HELL.) Note
battery volts with key off. Start engine, note volts, rev motor to shut off
the light, note volts, turn on high beams and heater blower, note volts,
shut off lights and blower, note volts, Shut off motor, note volts, turn on
high beams and note voltage drop till it hits 12.5 or less, shut off
lights, watch volts rebound for 5 minutes, note volts.
With these voltage readings we can KNOW if their is a problem with either
the alt or batteries.
I have also updated the dash to now have the built
>in tach, is there a way to test if this dash light is not functioning
>properly.
If it's not coming on when it's a'spose-ta it's not functioning properly.
Is this bulb holder spiced into something other than the feed from the
reostatt (dash light brightness control)? If all the other dash
illumination is functioning and this one isn't, it's not hook up right.
>
>I am thinking perhaps there is a short somewhere on the auxiliary battery
>side, causing the LED to dip into the yellow, causing the alternator to work
>harder, and it has just decided it is too much(?) Does this sound
>reasonable?
Yes, after verifying batteries and charging with the above data capture,
check the battery voltage again the next morning. If it drops more than
half a volt overnight, you could have a parasite infecting the electrons
somewhere.
>
>I assume I need to measure battery voltage(auxiliary), while pulling fuses,
>watching for any change in voltage, thereby isolating possible causes of
>power draw( if any exists(?)) It seams all the vw problems I have had in
>the past are very common, and somebody on the list has figured out the
>solution, so whatdoyathink?? Do I need to buy the 350 dollar alternator,
>what about rebuilt. Any and all advise appreciated. TIA
If you confirm a weak alt, a Bosch Reman will do you proud at maybe 2/3rds
the dealer list price.
Just like the multimeter, stay away from products designed to be cheap.
They are made of compromises that will waste more time/money than you
thought you could save with the weekend FLAPS brochure special slow movers
at half price.
> David Johnson
>Phone: 620-3251 Fax: 620-3540
>Compliance and Enforcement Technician
>Timber, Horsefly B.C.
Boy, I sure wish we had someone like you around when I was surveying in the
Olympic Pennisula forests. Dem horseflys grow real BIG on elk blood. They
would not comply with our demands to stop tearing hunks of flesh off us and
we had not been adequatly trained in enforcement, evidently, 'cause our
technique was marginally effective as verbal censures only with a self
flailing ritual thrown in of no consequence.
Hope you comply with my procedures, 'cause I won't enforce them on anyone.
Search the archive for Subject:Deutches Method, Multimeters for more
details on this essential tool for knowing fur shur what's up with your
electrons.
T.P. Stephens
San Juan Island, WA
