I notice a radio noise suppresor on the old voltage regulator. Does that need to be used with the new alternator?  Don't have my new engine running yet, so unable to just try the radio without the suppresor hooked up.  Dave V

SE Wis

Thanks for that advice. Should be easy enough.  Dave V.

SE Wis

good advice thanks for sharing..



"Came too close to dying to stop living now!"

A little diagram I drew to show diode in system.

"The Master Cylinder"

Enjoying life at the beach in SOCAL

Dave, I wasn't asking because you might have the wrong brand nor would I tell you that you should keep it all Ford. The Delco alternator is a great alternator and available everywhere (I have a 10SI on my '55 Ranchwagon). I asked because of the situation I mentioned above. If the Delco three wire alternator is not wired correctly you may (not saying you will) get back feed to the ignition thru the idiot light. Just trying to save you some excitement...

Two solutions to consider IF you get back feed;

• Insure your exciter wire, the one running from the ignition switch to the "Idiot Light" is connected to the accessory terminal of the ignition switch NOT the ignition terminal. This isolates the alternator from the ignition when the switch is in the OFF position.
• Install a diode in the exciter wire near the alternator to prevent  back feed. I use a 6 amp rectifier diode, 6A05. Radio Shack part # 276-1661.

"The Master Cylinder"

Enjoying life at the beach in SOCAL

Master cylinder    The alternator that i am using is a 10SI with the internal regulator.  I know it's not the correct brand but it is a nice easy swap and less to diagnose when broke down on the road.  Thanks for your help.  Dave V

SE Wis

If you look at the regulator it will have 2 wiring harnesses connected to it. One runs to the original generator, the other joins the main harness that runs thru the firewall. You want the main firewall harness, it will have 2 terminals on it that connect to the original regulator.

The terminal with the lighter gauge wire is the Gen Light, you can test it by grounding it with the key on, the Gen Light should come on when it is grounded.

Do not ground the other large wire terminal as it is 12v hot all the time and you will burn the harness, Make sure you insulate it well during your conversion. There will be 2 wires in that 1 terminal, they must remain as the horn relay is powered from there.

Hi Dave. It connects to the "A" or Armature terminal on the voltage regulator. The other wire to the "idiot" light or charge indicator comes from the ignition switch.

"The Master Cylinder"

Enjoying life at the beach in SOCAL

Great to have the use of the site back.  I'm installing an alternator on my 56 Fairlane. Can someone tell me where the idiot light connection is under the hood?  I'm thinking it is one of the wires on the voltage regulator. Which one?  Dave V

SE Wis