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Old 03-02-2019, 11:27 PM   #3
Flathead Fever
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Join Date: May 2010
Location: Yucaipa, CA
Posts: 599
Default Re: Off topic ford alternator question

That is a neat boat, it has a lot character. I want one here in SoCal to go ocean fishing but I don't need anymore more projects.

Here are some diagrams for marine alternators. It shows the EXC terminal going to the ignition. I'm guessing "EXC" is for exciter? The "S" terminal is the stator. Ford calls it the stater pulse rev counter for tachometers. I don't know anything about that? I do know that 1965 mustangs used an idiot light wired to the regulator "S" terminal that was also wired to the "S" terminal on the alternator. The 1966 mustangs have ammeters so the "S" terminal was not used. That is what I know about the "S" terminal. It sounds like on marine alternators it powers the tach with a pulsing AC voltage. I think the "S" terminal is the one they are calling the AC tap terminal in these pictures.

I found where somebody wrote this. "Nearly all outboards made in the last 40 years use alternator (stator) driven tachs. The tach counts the A.C. pulses from the alternator. Car tachs counting primary ignition pulses won't work on them". Who knew?

Last edited by Flathead Fever; 03-03-2019 at 12:18 AM.
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