Date: Wed, 16 Jun 2010 14:18:01 -0700
Reply-To: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Subject: Re: 12.2 V at rest ('85 Westy w/2.1L)
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Hi Rocket,
not sure if I made it clear ...
though I think I mentioned it twice...
I had a fat volt less charging voltage at the battery than at the alternator
with engine running and alt. charging. In almost a year of living with hard
cranking or battery gets too weak in only a few days...
this other cable fixed it.
it was black and white too, not 'sort of' ...but 'thank you finally ! "
lol.
about what is good charging voltage ..
I think lower is better for longer battery life.
Higher is better for good starting cranking.
the guy who originally turned me onto solid state adjustable voltage
regulators for Bosch alternators ...and starter/alternator rebuilder guy -
he likes to see them run at 14.5 volts.
fwiw.
anyway, what fun these fine vans are !
Scott
turbovans
----- Original Message -----
From: "Mike "Rocket J Squirrel"" <camping.elliott@GMAIL.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Wednesday, June 16, 2010 11:49 AM
Subject: Re: 12.2 V at rest ('85 Westy w/2.1L)
> With all due respect to Scott, who has forgotten more about Vanagons
> than I will ever learn and is willing to share it all....
>
> More/fatter wire from the alternator to the battery should not result in
> higher "morning after" battery resting voltage (before starting the
> engine) /unless/ the battery doesn't get a good charge while driving the
> previous day.
>
> Measuring voltage at the dash with a meter of unknown accuracy is not
> very helpful unless there are no other circuits in the dash that are
> drawing current. For example, with lamps on, the voltage at the dash
> will be quite a bit lower than at the battery; instead, a reasonably
> accurate meter connected directly to the battery terminals, as others
> have suggested, is the way to go. Monitoring this voltage while driving
> will show whether the battery is getting sufficiently high voltage to
> put a charge into it. Dennis Hayes wrote yesterday that "13.8 volts
> keeps the batteries at or just below the gassing threshold. While it
> will not fully charge them it prevents damage from long trips."
>
> In my '84, with the stock alternator > battery wire, I routinely see
> 13.1 to 13.5 V _at the dash_ (cigar lighter socket) and 12.5 to 12.6
> volts the "morning after," and that seems to be a pretty okay normal
> value.
>
> Lower than expected charging voltage at the battery when driving could
> be due to heavy loads -- headlights, etc. -- all of which pull their
> power through the same wire that connects the battery to the alternator
> and which has to do double-duty powering those loads and charging the
> battery at the same time.
>
> Karl, you didn't write what voltage you see at the dash when driving.
> You might look at that with the headlights on and off.
>
> As for the starter, running more/fatter wire from the alternator to the
> starter solenoid should not result in more juice in the starter since
> the alternator isn't doing anything useful when starting; the main
> current path to it comes from the battery. That's the connection that
> would benefit from beefing up.
>
> At least that's how I sees it.
>
> --
> Mike "Rocket J Squirrel" Elliott
> 84 Westfalia: Mellow Yellow ("The Electrical Banana")
> 74 Westrailia: (Ladybug Trailer company, San Juan Capistrano, Calif.)
> Bend, OR
> KG6RCR
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