On a Ford style starter relay, there are two skinny studs/terminals, one marked S where the switch wire goes, and one marked I.

A whole bunch of various applications use these type relays, everything from riding-lawn-mowers to Diamond-T trucks.

What goes on the "I" terminal ??

I know that several applications don't even use the "I" terminal, and some specific application relays have a spot for an "I" terminal, with no terminal there.

As best I can ascertain, there is no continuity between the "I" terminal and any of the other three terminals.

Thanks.

 

The "I" terminal is used to bypass the ballast resistor in the ignition circuit; it applies full battery voltage to the coil for a hotter spark during cranking conditions.
So when the solenoid is energized you should get 12 volts from the terminal in relation to ground.

It has been awhile since I have worked on a spark-ignited engine, I think this how it used to work.

Jim

 

Thank you, sir.

I guess that is why the "I" terminal is absent on many of the starter relays that are diesel specific.

 

LOL, Bearkiller, Jim is 100 percent correct, the only thing he didn't mention is it went out with points type systems, and many today have never even seen a points type distributor much less work on one...

 

Hey, some of us still have a dwellmeter (all the way at the bottom of the toolbox).

 

So if I was to refer to a Charles Kettering or a Kettering ignition most of the youngsters would go Huh? What is that?

Coil, points and a capacitor such a basic idea yet it worked for so many years.

But all of us use one of his inventions every day in your truck, if it hadn't been for Charles Kettering we would still be out front hand cranking out engine to get it to start. His invention was the Self Starter which also doubled as a generator.

Dwell Meter, lets see I still have my OLD AC Delco Dwell Meter, Analog Voltmeter, Carbon Pile load tester, Sun Oscilloscope, Heathkit Exhaust Gas Analyzer (I built myself) and many other pieces of test equipment..
How many of you know what a Growler is?

I now have a reason to use them again; my son and I are restoring his 1962 Cadillac DeVille with a 390 4V engine. Most of the pieces are pictured in the Factory Shop Manual.

Charles Kettering was an interesting man while not as amazing to me as Nikola Tesla but I am easily amazed.
Jim

http://en.wikipedia.org/wiki/Automobile_self_starter

 

Jim, interesting review! I was looking on a shelf the other day and found a tach which has a small rubber tip for holding us against a shaft that has to be 45 years old. Also, a vacuum gage which was for SU carbs adjustment. Kinda like owning an eight track now.

 

My old 500,000 mile K-20 Chevy, that I bought brand-new in April 1978, has a functioning 8-track stereo in it at this very moment, with a tape in it, and if I flip the toggle-switch on, I gaurantee it will play.