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wiring questions

1492 Views 3 Replies 3 Participants Last post by  Ken Kaminski
I have replaced the old alt with a new internal regulator design. I printed out the directions on how to re-wire this application but found that my info stopped short of printing the whole thread. I got as far as the blue/white wire for the dash light going to the left spade post of the altenator. What's next???? I couldn't bring up any info in the search department so I apoligize for any repitition.
Also, I replaced the soleniod with a 1 spade/post version. I have a '71 GT & originally had 2 spade/posts on either side of the main wire from the battery. What do I do with the extra wire?? Do I need to go back to the old design??

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Ken, as far as the solenoid connections, one is used to engage the solenoid and start the engine, the other is to apply 12 volts to the coil during starting. When the ignition key is released from the start position, the resistor wire from the fuse panel supplys power to the coil. A little insight on coils, from the time the manufacturers went to 12 volt batteries, the ignition coils have always been 6 volt. Ford uses an internal resistor in the coil, GM and others use a "ballast resistor" to drop the voltage to 12 volts during normal engine running. If you feel you don't need 12 volts to the coil during starting, you can leave the coil wire disconntected and tape the end of it. HTH.

where to look

Ken, I think all the info you'll need to finish the upgrade is in the Forum under Electrical in the thread labeled Altenator/ Headlight Upgrade.


Basicly the other wire needs to hook-up to the big terminal on the back of the alt.

As to the extra wire on the starter, If you decide you do want to hook it up, I would recommend hooking it up using a slightly modifies "otto-start" as a first step:


Then, after that is installed and working, obtain a decent sized diode from your local electronics store. You'll want one that can handle a couple of amps. The annode of the diode will ned to hook up to the one spade lug you still have, and the cathode can then be hooked-up to the wire currently have not connected to anything. This will allow full battery voltage to go to the coil during starting, but will keep the normal coil voltage from making the starter run the whole time the car is on.

Good luck!
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Thanks, guys.
As with any undertaking, it becomes a learning experience. By the time this thing starts & charges I'll know all about diodes, etc, etc. Well, at least where they go if not what they do.

Oldopelguy. These were the threads that I had printed out before but I didn't get the whole story. They were helpful up to a point. Now I have everything that I need........hopefully.
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