hi.
low beams on at idle drop charging voltage from 13.4 volts to 13.2.
recovered to 13.4 revved up.

I'm sure with all accessories in it would really suck it down.

say it is lowish current..
all there is to work with ....assuming the new Interstate battery is good ..
are alternator or the voltage regulator in it ...
and cables, wires, and grounds.

the amp meter sounds good ..
even if it does say current is low ..
'something' in the charging circuit is sleepy/lowish ..
I only see those two main avenues to peruse ..
alt/reg..........and connections and cables , assuming battery is good.

it's an easy experiment or test to quickly run a fat wire from Alt Pos post
to batt positive post.

I like that ..
if you need a bigger wire, you need a bigger wire.
How profound !
----- Original Message -----
From: "David Beierl" <dbeierl@attglobal.net>
To: "Scott Daniel - Turbovans" <scottdaniel@turbovans.com>
Cc: <vanagon@GERRY.VANAGON.COM>
Sent: Sunday, March 13, 2011 9:32 PM
Subject: Re: charing voltage to battery - 85 vanagon

> At 11:37 PM 3/13/2011, Scott Daniel  - Turbovans wrote:
>>when there is 13.8 volts of charging ooomph at the alternator main
>>terminal ...
>>
>>and only 13.4 at the (  new  ) battery .
>
> What's the charging current?  And before you trust your little
> stick-on-the-wire gizmo, see what it reads with the engine stopped.  Then
> go pay the $60 for a Sears 82369.  They invented DC clamp-on ammeters
> while I wasn't looking, and this one comes with a thermocouple and
> Volt/ohm/continuity/cap meter built in.  That shroud around the charging
> wire means you have to get way too close to the alternator's iron core for
> the little magnet thingy to be happy.
>
> But anyway...start by getting out your voltmeter and finding out where
> that 400 millivolts is getting lost at.  Also, if the lights and blower
> and rear blower and defogger and wipers and megawatt stereo and all that
> stuff are on, what's the voltage drop then?  That goes back to what's the
> charging current...
>
> Yrs,
> d
>
>