Alternator -Question on how to remove from housing, Marchal alternator question

[whimtreasures]

Appreciate any help someone could offer. I have a 911 with 2.7 liter. It has the Marchal 71223702 alternator. I need to install a new one and I have the fan housing/alternator out. How do I remove alternator from housing as I dont want to damage anything? Secondly, is there a cross reference to the Bosch or ? alternator as a match for the Marchal? These Marchals seem hard to find and when I do a search online for the make and model, the Bosch comes up. Are they the same? I just dont want to buy the wrong one. Can anyone help? Thank you..

[clarkd]

Sounds like you have a red plate SEV alternator. I recently rebuilt the same type alternator myself because I couldn't locate an exact replacement. If you aren't up for rebuilding it yourself then you can take it to a local rebuilder and have it repaired. The parts are still available.

I can't say for sure but the alts you are finding online maybe a match and just branded as Bosch because they were rebuilt by a Bosch contractor.

Most on this site will advise you to take your alt to a local rebuilder and avoid the low cost auto parts store rebuilds.

The red plate is an isolation plate which means this style alt requires an external regulator with a slightly higher set point than an alt with a dedicated 3 diode set supplying the voltage regulator.

I think Pelican sells a new replacement that will fit but it has an internal regulator. There are many posts on how to convert from an externally regulated alt to an internally regulated alt. Some will tell you internal regulators get too hot and fail more often than external regulators.

As far as separating the alt from the fan. I used a hammer and brass drift on the end of the shaft to drive the alt out of the fan. I supported the fan on wooden blocks with the alternator hanging in the middle. Once I got a little movement it was not difficult to separate the parts. There are posts with other methods to separate the alt and fan but they all seem to involve some type of banging.

[47silver]

Is the fan connected? If so then put thick towels on the ground. Get 2 2x4's. Spread them so the edges of the housing hit the wood. Hold a few inches above the wood. Drop housing. Fan and alternator come out.
If alternator is out and attachéd to the fan, use the same technique but put the wood over a 5 gallon bucket with towels on the bottom to catch the alternator.

Works every time and you won't damage the alt shaft.
I send my alternators to stellar in Pittsburgh. Don't bother with remanufactured

[Lorenfb]

"I used a hammer and brass drift on the end of the shaft to drive the alt out of the fan."

NOT GOOD! That's how it's done at Pep Boy's or at the Shell gas station.

"Hold a few inches above the wood. Drop housing."

That works or tap the housing on the block of wood with the alt. facing down.

Bottom line: Avoid using any type of hammer on any Porsche parts.

[johndaroza]

thank you 47 silver : I was tought rong buy a 30+ year porsche mac. I just wonder why he dose it rong, It been a thron in my ass for over an hour , 2 drops it was out ,...... THANK YOU THANK YOU !

[B61]

indeed 47Silver simple and great Trick ! Works like a charm.
Is theer a similar trick to remove now the fan from the alternator shaft?

[47silver]

I use a piece of 6 inch plastic pipe, it fits over the alternator and should contact the ring of the fan. Same method, drop the alternator into the pipe(make sure you do not hit the blades). The alternator will fall out , Use some foam or towels to catch it

[B61]

thanks, sound easy also, will try it !

[47silver]

make sure you measure your alternator depth if you get a rebuilt one. there are a couple different depths. That will cause your fan to be in too far or out too far. It was such a hassle with mine that I ended up just getting mine rebult by a local alternator shop, Stellar alternator in pittsburgh can rebulld them (no affiliation). the original alternators use pressed in diodes, rebulits use external diodes that are soldered to the posts.