T3: My Fastback ate my voltage regulator

[Schmitt@aerovironment.com (Schmitt, Frank)]

The other night as I was driving back home on the freeway my generator light
came up for no apparent reason. I continued driving, comfortable in the
thought that I had 65 amp-hours worth of Optima deep cycle battery running
the headlights. Upon arriving at home, I made sure that the generator was in
fact spinning.

The next day I checked the voltage regulator as described in the Haynes
manual, and it came up bad. I replaced it, polarized the system with a big
screwdriver, and everything seemed fine.

Then last night I decided to go on another little trip and smelled something
getting hot. I assumed it was just that big resistor under the new regulator
warming up for the first time. However by the time I was on the freeway, the
light started to flicker, and before I got home, lit up again. This time I
had the new cheapo Pep Boys' special group 41 battery.

I'd like to avoid having to buy $30 voltage regulators every time I go on a
trip. What would y'all suggest I look at next? BTW the voltage was around
12V with the B+ terminals disconnected (and hooked together).

TIA,

-Frank