How many types/makes of Alternators are there for 911's?
 

Bosch, Marchal, Valeo, Rhone. (Internal/External Regulator)

Any others? What differences between them? Which one is preferred? Between '74 and '89, which one is most likely found?

:confused:

?

Good question. I will be looking for an alternator for my 82 soon myself.

What are the differences?

Enlighten us oh great ones............

The best of the lot was 1975 - 81 Motorola/SEV Marchal 980 Watt, externally regulated. 1974 and earlier engines require fan housing to be machined 9.3 mm deeper, or a 1975 or later fan housing.

Best to have your old one re-done by the local shop. Insist on marginal parts be replaced.....the labor to pull it out again is WAY more than the price of the parts....

Buying a reman can be a crap shoot as they only replace stuff that is broken.....I once opened up a reman and found parts in there that I would have thrown away.

Warren: I don't know what alternator is in my '80 engine but, the '82 I am working on has a VALEO 14V - 75A. (France)
It worked fine, bearings feel good, brushes are good and I'll be putting it back in once I finish the SS 3.2 conversion.
I was just wondering how many types/makes of alternators one would find in these engines. Fortunately, they are easy to get at.
Where does VALEO fit in? Any connection to Marchal?

How good are the ones used on 1986 engines?

Gunter,
My '80 has a Bosch AL400X, 75 amp. I don't know if it is original, the PO had it rebuilt (I don't think it is a reman..?). Bosch Alternators have a pretty good reputation so I'll get this one rebuilt whenever the time comes.