3-wire alternator

[ErichK]

Alright, in my 1986 GMC I'm trying to hook up a 3 wire alternator, I think I've got it down but I wanted to be sure. Better safe than sorry.




So in the picture, Wire 1 should go to the battery positive terminal, Wire 2 jumps to Wire 1, and Wire 3 should go to an idiot light correct? And also, how should I wire the idiot light?

Would hate to ruin this alternator and have to shell out for another
cheers

[keith61760]

This is the diagram I used with the wire kit I re-wired my truck with. It works good. Ignore the plug with the that it shows. Thats for the voltage regulator. Looks like you got it.

[454HO]

Smart choice to go 3-wire. But you do need to wire it correctly or else you will not be taking advantage of the benefit it offers - remote voltate sensing. So instead of jumpering the Term-2 over to the B+ post right at the back of the alternator, run a wire up to the distribution block on the firewall.

Here is a good read on why and how to correctly wire it - Mad Electrical

And here is a pretty good wiring diagram posted by another board member showing how the charge lamp indicator is wired - diagram

And one more thing, make sure the wire guage you use for the B+ connection is appropriate for the alternator's maximum output current. Use this as a guideline - wire size chart