Alternator Follies

An alternator is a pretty simple thing. It's a simple, field excited three phase AC generator with built in solid state rectifiers that is controlled by the current flowing in the exciting coils, rather than permanent magnets.

This completely escapes most so-called mechanics and parts counter people.

The basic principles of electromagnetism are taught in fifth grade science class and it is impossible to graduate high school without enough electrical principles knowledge to understand one. Yet, it's treated as A Great Mystery.

The parts counter men at each of the four chains selling parts in my area (we don't have Pep Boys, no great loss) are utterly unable to comprehend that anyone can understand the alternator or that one would want to fix the one they have instead of exchanging it for one on their shelf.

I finally was able to order what I wanted through a marine electrical supply house. They understand car alternators, because-with minor changes to meet USCG regulations-they are boat alternators too. Only they may be 12, 24, 32, or 36 volt, or positive or negative ground, or floating-from-case. I was able, in ten minutes, to order new bearings, rotor, and everything else not only to rebuild my existing case but upgrade it to full USCG marine compliance and increase its amperage to the maximum the case will safely allow.

Also, the man there was able to tell me what the parts clowns had not: that I should convert my setup from the "one wire" installation the previous owner had, to the full General Motors setup. It turns out the one wire setup, beloved of street rodders, is just not very good, and that if it were GM would have used it.

Although I would be happy to give the marine house a plug, they asked me not too. They have enough business as it is. But they referred me to this web site, which they have nothing to do with. And this one too.

Nothing on either of these sites is beyond anyone with a high school education. So why is it beyond all four of the national parts chains?