Fin,
The stock internal regulator in the Bosch alternator is lazy as
hell and doesn't keep very good regulation. To make the problem
worse, it measures the voltage right at the alternator instead of
at the battery, so voltage drop across the wire from alternator
to battery compounds the "droopy voltage" problem at high load.

You can disable the internal regulator and use an external
Ford style regulator instead. The ford regulator not only woks
better, but it has external voltage sense wire, so it can measure
the voltage right at the battery instead of back at the alternator.
(you need to run a small wire from alternator to battery for this)
I performed this conversion back when I still had a WBX, and
it made a great difference in battery voltage under a heavy load.
Mine was rock stable at around 13.8 volts under most any load.
It also made my headlights brighter, and my fridge work better
on 12 volts......

It's a common enough conversion amongst Volvo owners. I don't
seem to have a link handy, but Google with keywords "bosch
alternator" ,"ford regulator", and maybe "volvo" and you should
find instructions on how to perform the conversion...  it's pretty
easy and works *great*.

Steve
'86 Westy "Escape Pod"  (EJ22)
'84 Westy "Yard Furniture" (Blown WBX)
'73 Beetle "ain't got a name yet" (just bought it)

---------------------------------------

At 09:34 AM 7/15/2004, Fin Beven wrote:

>Here in SoCal during the summer, it's often a long, hot drive from LA to
>Bishop up Hwy 395.  North of Mojave there's a stretch where they encourage
>you to turn on the head-lights, even in day time.
>
>The lights, the heat, and the A/C cause my voltmeter to drop from a
>typical 13+ volts down to less than 12.
>
>I would have thought that the voltage regulator would compensate for this,
>but apparently not.
>
>Has anyone experienced this ?
>
>Has anyone experimented with upgraded alternators or more sophisticated
>voltage regulators ?
>
>Thanks,
>
>Fin Beven
>'90 Carat, Custom Camping Conversion
>Pasadena, CA