It's Official, I'm an Idiot

Well, we've all had one of these moments. I suppose that since I finally just completed the head replacement on the MG after the rebuild, it was time for me to screw up something else. So I think I've fried my alternator.

I took the MG out for a trip over the hill to Aptos, both to watch the Leland Boys Tennis Team play CCS Individuals today and to put the car under a full range of load conditions (after which I was going to retorque the head). Unfortunately, I turned my lights on for the wooded sections of Highway 17 and forgot to turn them off when I parked. When I tried to depart some hours later, the battery was dead.

But that's no big deal you say. Ahhhh....but it is for me. I enlisted the help of a Leland parent and proceeded to go through the usual jump start procedure: red cables to red terminals on both cars, black to black on the other car, and black to the frame of the MG. This would have been fine but for one small fact--the leads on my battery are reversed.

This is where it becomes clear that I'm an idiot. You see, when I resurrected the MG about a year ago after a 15 year period in our garage, I found that the car had been mysteriously hooked up for positive gound. This is pretty unusual for a 1974.5 MGB roadster. Of course, this arrangement had killed the previous alternator (which was a royal pain to replace). Anyway, when I put a new battery in I tried to change the battery leads around so that black would go correctly to negative and red to positive. But, after much penetrant and struggle, I simply couldn't remove one of the leads. So I gave up and decided to just hook it up with the wrong colored wires in place. I promised myself I'd remember this reversal in the future.

And I did remember it, but only after I began to see smoke emanating from under the hood. I quickly disconnected the battery and opened the hood to reveal my alternator smoking like a steam locomotive. A quick peek at the battery (which is entirely black) revealed a tiny "+" mark beside the terminal with the black lead attached, confirming my recollection. At this point I figured my alternator was shot (or, at the very least, not worth testing); so I had the car towed home.

However, despite the escape of a large volume of pungent smoke, my alternator may yet survive. When I charged the MG so that I could drive it back into the garage, the alternator warning light went off. A check with a voltmeter should provide more definitive information.