Upgrading Alternator Wiring Question

[wmpwilson]

Am I correct in suspecting a bad diode in alternator?

[ROOK1]

Sorry to revive such an old thread but I think its better to add to one rather than create another.

I have read this thread several times but still have questions. I am looking to make this "upgrade" today but I cant seem to find the wires Denise mentions. I have attached 2 pics (old alternator installed). One at the alternator end which made sense and one at the regulator end which didn't. My regulator has a black and orange wire that go into the harness. I am not sure which relay Denise mentions but I would think it is the one next to the regulator. I believe the other 2 I see go to the horns and radiator fan. The relay next to the regulator has a Yellow wire, black wire, white/black 2 wire one jumped to another terminal other to harness. I can not find the Red/Yellow and Violet/White Denise mentions.

Thanks in advance.

Chris '71 1608 stock wiring.

[mdrburchette]

Hey Chris. The relay you want is the one with the yellow wire, black wire, and 3 white/black wires.
Yellow goes to alternator and is the exciter wire.
Black goes to charge light on tach. You need to mate the yellow wire and black wire so you have an exciter from the alternator to the charge light.

The white/black wires are insignificant. You can either leave them attached to the relay or disconnect them all and get rid of the relay.

On the alternator, you will connect the big black wires to the post and the yellow should go to a spade connector if I remember right. The grey wire is useless so I have it taped up and out of the way.

The external voltage regulator has a grey wire (went to old alternator)
and big orange wire going to fuse block. I just left the old regulator on the car with the wires connected. You can clean up the engine bay by removing the wiring from it and either taping the wiring up or removing it. I left mine intact in case I had to go back to the original for some strange reason.
Hope this helps.

[ROOK1]

Helps a ton, thank you! But I ran into another problem. The old alternator pulley doesn't fit on the new alternator. I have the pulley coming but that means I am down for a bit.

[mdrburchette]

Dang, what a bummer! One good thing about having a Fiat junkyard is I just pulled an alternator right off a parts car when I did my upgrade.