Alternator Wiring

[hooperdoski]

I pulled my engine out of my 71 Corvette about four years ago. My engine is in now and I'm in the process of hooking things up. Today, while hooking up the alternator, I realized I'm not a 100% sure about where the black wire goes. I believe it goes to ground. The alternator in the car is not stock and doesn't have a ground terminal, which I believe the old one had. There are four wires all together. The plug with the two wires is hooked up and the 10 gauge red wire is connected to the battery terminal on the alternator. The only wire left to connect is the black wire. My wiring diagram is vague. Should that black wire go to ground?

Thanks.

 

[gmjunkie]

I pulled my engine out of my 71 Corvette about four years ago. My engine is in now and I'm in the process of hooking things up. Today, while hooking up the alternator, I realized I'm not a 100% sure about where the black wire goes. I believe it goes to ground. The alternator in the car is not stock and doesn't have a ground terminal, which I believe the old one had. There are four wires all together. The plug with the two wires is hooked up and the 10 gauge red wire is connected to the battery terminal on the alternator. The only wire left to connect is the black wire. My wiring diagram is vague. Should that black wire go to ground?

Thanks.

The black gos the back of the alternator case,there should be a hole threaded for a short 5/16ths bolt!!

 

[hooperdoski]

Nope, there is no 5/16 bolt hole. Like I said, the alternator is not stock. However, I do believe if the 5/16 threaded hole was there it would be a ground.

Make sense?

 

[gmjunkie]

Nope, there is no 5/16 bolt hole. Like I said, the alternator is not stock. However, I do believe if the 5/16 threaded hole was there it would be a ground.

Make sense?

Does to me!!

 

[Mr. Chuck]

Nope, there is no 5/16 bolt hole. Like I said, the alternator is not stock. However, I do believe if the 5/16 threaded hole was there it would be a ground.

Make sense?

One alternate ground connection for the Black wire to the alternator housing would be to attach a spade lug (opening for a #10 - #12 screw) terminal to the free end of the black wire, back off (loosen) one of the through bolts (one of the ones holding the alternator housing halfs together) just enough to slip the spade lug under and then re-tighten the bolt.
My 81 has the same black ground wire (large diameter) ring lug as shown in "gmjunkie's" thumbnail; except my 81 alternator also mounts a wire / tubing clamp at the same large 5/16" dia bolt on the rear housing to support gas vapor recovery & assorted vacuum lines.