Fan Housing – Alternator question
 

Hi All,

I have two 911 Fan housings both marked 901 106 101 5R.

They are different in that one has a deeper seat for the Alternator.

The alternators are of a different thickness to allow for this difference.

One setup is from a 914-6 (911T) but I am not sure what engine the other one is from.

I have never seen a part with the same number be different. Can someone explain the difference??

Thanks,

Ken

B/c it isn't a part number - it is a casting number. The deeper recess will be a later housing w/bigger alt - can't remember the specs off top of my head. I'm sure someone will, though.

Casting # or P/N, still seems odd they would be different.

Ken

Googled the Marchal alternators.

The short alternator that fits the shallow casting is a 55 Amp unit.

The long alternator that fits the deeper casting is a 70 Amp unit.

Ken

Ken

When you think it through, I think you may not think it quite so odd that the casting numbers stay the same until the casting itself needs to be changed. At that point new molds are in order. But until then, use the old masters. Since the parts are machined anyway, it is easy just to change the machining - as in this case.

Heads and cam carriers are other prominent examples (though the heads get a casting date, so they could make other changes where Porsche thought it worth while.

Walt Fricke

Ken, interesting find!

Usually you have to get a 930 (911SC) casting number shroud WITH coil studs to fit the long one. Perhaps one of yours has been machined?