Alternator wiring

[911 envy]

I am replacing alternator and voltage regulator in my 74 911 with a Bosch alternator with built in regulator. I’m fairly certain I know where to hook the hot red wire and blue wire that goes to the instrument panel. I cut and capped the black voltage regulator wire. I’m not sure what to do with a white or faded tan wire that remains. I took pictures of the original wiring but they’re not helping me. I’d appreciate any help I can get.

Ron from Indiana

[PeteKz]

"Tan" should be brown. That's the ground wire. It doesn't do anything with the VR removed, but I would ground it to any convenient nut/bolt/screw.

[911 envy]

Thanks for your help. If I understand correctly the only important connections are red to B+ and blue to D+. Not sure but I also take brown to any place I can use for ground. Wiring diagram says D- but maybe that’s not necessary.

[911 envy]

Originally Posted by PeteKz

"Tan" should be brown. That's the ground wire. It doesn't do anything with the VR removed, but I would ground it to any convenient nut/bolt/screw.

When you say ground it to any nut bolt screw are you saying any nut bolt screw on the alternator or somewhere else close to the alternator?

[PeteKz]

Either the case of the alternator or a stud/nut/bolt on the engine.

[911 envy]

Thanks again.