Pelican Parts Forums - Alternator Question

While completing a coast to coast run across Canada I believe that I fried my alternator, but want to make sure.

Was downshifting while approaching a traffic light and heard an ugly groan / growl / grind sound from the rear of the car. I thought I had shifted from 5 to R so shifted back to N and then to 4.

The Oxy Sens and G light both came on. I pulled off as soon as possible, but did hear some slight grinding while getting to a stop.

Shut the vehicle off and did some cursory checks on the side of the road - wind and rain and cold did not make me want to do too exhaustive of a check. All seemed in order and fan belt tight. Re-started the car without problems but the Oxy Sens and G light stayed on. Checked the car while it was running and the fan belt was moving as it should.

As I was on the return leg of my trip, and miles from any Porsche knowledgeable shop, I decided to keep driving. Used the bare minimum for electrical - wipers once in a while, but noticed the electrical side was not working as well. Eventually the tach climbed past red line and then returned to zero - all the while the engine did not change its pitch.

After about 50 miles the engine died and I coasted to a safe place. Could not see anything obviously wrong but car would not restart. Eventually ended up towing it 500 miles home.

My question is whether the grinding / growling sound was the signal that the alternator had failed. Haven't had a chance to rip anything out yet, and may not for several weeks, but want to start in on the research.

Its a 1980 911 SC, 3.0 litre, external regulator.

Thanks

jb