Need Alternator for 77 911S (I think)

[dave123]

Alternator light came on 100 miles from home. Made it on battery only and have done the following tests after recharging battery:

Cigarette Lighter VM 12.5v with engine off, 12.2v with engine on.

Marchal voltage regulator with engine running D+ 1.6v DF 1.6v.

Alternator started making "bad bearing" noises.

I assume a new alternator with an internal regulator is needed, but I am having trouble finding one. Pelican has one that requires trimming the plastic housing, but I don't know how involved the modification would be. Any other reliable sources? Brands to avoid?

[Mixed76]

Take your old one to an alternator shop and have it rebuilt

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[Jdub]

^ Rebuilding the original is the best route, but it is getting harder and harder to find shops that will or can do this. To find out, ask around at Porsche shops in your area because they will know.

Your next step may be to ID and then purchase a used alternator in good shape. Finally, there is shoeing in a new version with mods - be sure the new one has the same specs as your current one. Also, very important at this time to consider replacing the ground cable because they will hide corrosion - take a meter to each end to verify no resistance or very little (sorry do not know the expected specification for this).

Good luck!

[dave123]

Thanks Mixed76 and Jdub. My mechanic had a rebuild with internal regulator. He made small mod to the fiberglass shield and I am back on the road!