I haven't smoked it yet!

[futuresoptions]

I decided to stay with the original size alternator on my 77' 911s versus machining the fan housing for the later style alternator that I originally purchased. The original alternator on the car was a 70amp SEV Marchal, I purchased a second alternator and it is a 70amp SEV Motorola. I installed the alternator and it fits correctly, however when I started my car the alternator light came on and did not go off even at 3000 rpm. I checked battery voltage and it is 12.3 volts. I ordered the new alternator as per year and model of my car, and installed a new ground wire to the alternator. What I think may be wrong is that the black plastic cover on the Voltage Regulator says SEV Marchal 14v. Should I have to purchase a Motorola voltage regulator to make this alternator work, or should it be working okay with the Marchal... I would appreciate any help on this matter..... If I need to pull any more hairs out I will have to move to my backside to do so......

Thanks in advance!!

[Early_S_Man]

Marchal and S.E.V. Motorola parts are all compatible ... many times only the markings are different, depending on the target market for the replacement parts.

Voltage regulator can cause the zero output situation you have. As I recall, there was a later regulator with a gray case for the 70 Amp Marchal or Motorola alts.

Does your car still have the three-pin noise suppressor inline before the regulator? If so, remove and discard ... test output Voltage again with relay panel connector plugged directly into the regulator.

[futuresoptions]

Went ahead and did this and no change..... still 12.3volts at battery while running and alternator light is still on. I believe I wired the alternator back correctly and the alternator that I took off was charging fine, just the threads at the pulley were so bad that I had to change out.....