Yes, that black thing is the regulator. It is part of the peice that holds the brushes.

I read somewhere that the current output of an alternator is related to the battery condition - with the implication that a bad battery can cause the alternator to generate excessive amperage - which might burn out bulbs.

Here is a good link on bench testing the regulator.
http://www.geocities.com/fwarner_au/tekdata/Reg_test.htm

good luck,
Todd '88 westy

-----Original Message-----
From: Matthew <poll7356@UIDAHO.EDU>
Sent: Oct 15, 2003 2:01 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: [WetWesties] alternator output voltage?

I just measured my voltage at the alternator- I get 14.36 volts. it
remains constant when i rev it. I'll put in another regulator i have and
see what that does. So is the regulator that black thing on the back
that is attached to the brush?
thanks
m