At 08:41 PM 9/14/2009, Steve Williams wrote:
>Just to follow up on my '84 Wolfsburg Westy with the anemic alternator ...
>
>I bought an alternator at an AutoZone in Flagstaff, just so I would
>get completely stuck over the holiday weekend.  I left it in the box ...
>
>(With the old alternator:) measured the voltage at the starter
>battery at idle and 2,000 rpm: 13.1V with the headlights off.
>
>I pulled the regulator out of the Autozone alternator ... got it
>installed (on the old alternator).
>
>I started the engine and measured 13.75V at the battery at idle and
>2,000 rpm with the headlights off.  With the high beams on, it
>dropped to about 13.5V.

Even after I wrote the above, I remained suspicious of the old
alternator, so yesterday I had GoWesty install the AutoZone
alternator, along with one of their alternator brackets.

And, oh no!  The AutoZone alternator measures only 12.8V at the
starter battery with the headlights off.

I measured 13.4V between the alternator case and the big B+
stud.  So, yes, I'm thinking of running a fatter wire to the
battery.  But shouldn't the voltage be higher?

The GoWesty tech seemed satisfied with 12.8V, but everything I've
learned about lead acid batteries tells me I want more voltage to
charge it fully!  Am I wrong?  Do we have experts on this forum, or
can someone point me to trustworthy advice on the inkernets?  What
about the deep cycle battery?

Sorry to go on and on about this.  I just don't feel like I
understand yet what the voltage SHOULD be.