Alternator

fuch'd · fuch'd's Garage

Gents,

My '74 2.7 has a #901.106.101.5R fan shroud. I am trying to find an alternative to the stock Marchal alternator.

I tried a replacement Bosch, but the shaft was too long and caused the fan to protrude out of the shroud and the belts wouldn't align.

Any help on this please?

If I've posted in the wrong forum, I apologize in advance.

Thanks,

Brian F.
cmpd_patch@yahoo.com

Flat6pac · 08-03-2013, 06:28 AM

If your alternator is too long, you need one for the early cars, such as a 73 alternator. The change is 1975 where the 5R had a back space thickness of 19mm to allow fit of the larger alternator.
Your 74 has a back of about 24mm and your alternator is a 75 and later that youre trying to fit.
Where in NC are you?
Bruce

fuch'd · fuch'd's Garage

I am in Charlotte. The unit on the car is identical to this Marchal.

fuch'd · fuch'd's Garage

For some reason, Pelican won't attach the photo I've uploaded.

The alternator is Marchal, marked 712.237.02 with a red half-moon back plate and four connectors, three marked "61" "D" and "B+". The regulator is a screw panel just above with a tab connector marked "D-".

I cannot tell which of the replacement units offered by Pelican would be a direct exchange.

Any help?

Flat6pac · 08-03-2013, 09:21 AM

You have to go to the orange square (post reply) because you cant load pictures @ quick reply

Flat6pac · 08-03-2013, 09:24 AM

look for this part number

911.603.120.00

fuch'd · fuch'd's Garage

This is what is in the car:

crummasel · 08-04-2013, 04:14 PM

To fit a later alternator you can machine the inner flange of the fan housing where the alternator attach on a lathe for some 6 mm (as far as i remember).

Thats absolutely no stunt.

fuch'd · fuch'd's Garage

Thanks to all who replied. I (in fact) do have an external Voltage Regulator (amazing what you find when you pull panels) that is an SEV Marchal unit date coded 07/85.

My guess is that it has given up after 25 years, considering the alternator rebuild was less than four years ago (and less than 2,000 miles).

I have pulled the battery and fully charged same. I figure it will be easier to drop the $60 for a new VR and install to see if it is fixed, before i pull the alternator again.

durant7 · 02-27-2022, 05:32 AM

Trying not to create a new post on a familiar topic. I have a '77 with a 2.7 stock from what I can tell. A rebuilt Alternator 712.237.02 SEV Marchal was put in back in 2007 or 40k miles ago. It died this fall and...I chose to have it rebuilt vs. trying to find the correct already rebuilt. When I put it back in my 901.10610.5R housing, the alternator housing cracked...back half not the front half with the wires. Maybe it was there. Maybe not. My rebuilder said he can try to repair. Got to believe there are some of these lying around that might yield a non crack repaired housing. Thoughts? New to Porsche and hunting down parts. Wanted some input before I drop it back to the alternator rebuilder. He said my particular alternator is not common.

durant7 · 03-10-2022, 01:39 PM

So. Got a new frame. Most expensive alternator ever

So, my question now, while I have wide open access to the top of the cylinders, do I clean with simple green to get oil off or just put it all back together? It was also suggested by 2013 Interstate battery might start the car just fine...but get a new one.

Advice?