I am trying to convert my '71 F-250 (360 FE) over to Duraspark Electronic Ignition. I have refered to the forum, and (I think) every schematic known.

My problem is the truck will spark and run as long as the key is in the start position. When I let off the key, the truck dies.

In diagnosing, I switched the red and white wires coming out of the ignition module. So, when switching, the White wire goes the "S" terminal on the solenoid and Red Wire to a 12V key on source under the dash. When cranking the truck, it won't start or fire. If I leave the key on and pop the solenoid (screwdriver from batt. to "S" terminal) it will fire up and run and idle wonderfully.

To put my mind at ease I had Auto Zone test the module and he tried it six diffrent times and it worked everytime.

I did this conversion to my Dad's truck ten years ago, and I went over to his house and looked at his truck (he has a '70 F-250) I had wired the red wire to the ignition coil wire coming out of the ignition swtich and we left the white wire coming out of the module un attached - just hanging. He has been driving this truck for that 10 year period without any problems.

The only issue I have now with what we did then is the module is getting only 7.3V becuase it is running off the circuit with coil that has the balast on it.

It seems that red wire coming out of the module doesen't work or do anything!

Should I copy what I did 10 years ago, or figure out what I am doing wrong and fix it according to the diagrams? Wait a min, I do have it wired according to the diagrams and it dosen't work!

 

IIRC, when I did this on my '72, I found a wire on the back of the ignition that was hot in run AND start.

 

The RED wire AT THE MODULE is hot in RUN.

The WHITE wire AT THE MODULE is hot in START.

The primary resistor wire powers the coil in RUN only. It is never used to power the module.

There are schematics here:
https://www.ford-trucks.com/forums/member.php?u=1811

Some testing machines do not test the start circuit.

 

I think I read somewhere that when the white wire recieves power that it does something to the dwell or something like that to help it fire better. Not needed to run or start but there to help ease starting.

 

I Love this FORUM!

I think I am going to try leaving my White Wire on the "S" terminal of the solenoid whether it works or not.

I am going to find the coil wire that comes out of the ignition switch and splice the red wire in before the in-line resistor.

I think it will work that way. Thanks for the help!

 

The white wire tells the module it is cranking, and retards the timing. This helps especially on hot starts, since the starter isn't fighting an early spark.
If you are still running the old can-style coil, you need to run a resistor of some sorts. 7.3v sounds about right. If you are running a newer E core coil, then you can run straight 12v on the red wire. I did this on my 84, no problems except when I left the key on for a couple hours- melted the epoxy right out of the box. Just running, though, it lasted for the three or four months I had it in there.

 

It worked. I wired the white wire to the coil wire coming out of the ignition switch (within the first 4" before the inline balast). Red wire still on the S-terminal of the solenoid. Fired right up the first time. I still don't know if the red wire really does anything but hey it's there just in case. Thanks for all the help!

 

so ur saying that u hooked up it opposite then wut all diagrams say? cause they all say to hook up red to 12v. and white to 's' terminal...

 

Yeah, hook the red up to the coil wire, and the white to the selonoid.

 

Yes, Red wire to Solenoid "S" Terminal, and White to the Coil Power wire coming out of the ignition switch.

When I had it wired so the white was to the solenoid and the red to ignition coil wire it would fire right up until you let off the key to go to the RUN position. Then it would die.

I originally had the white wire wired to just a 12V "RUN" power source and it would only start and run if I was bypassing the solenoid with a screw driver.

 

Sounds like your module may be bad. I can't really tell but you may have it wired backwards, check my post above. Check your wiring and wire it EXACTLY as I specified. Set your timing correctly. You just may have the timing set too far advanced also. Remember we are talking the wire colors AT THE MODULE LEADS, not out in the wiring harness, wire colors in the harness can vary and are sometimes reversed for the red/white.

 

This is not a subject you can afford to ignore, and "just get it running."
If you have that module wired incorrectly, you run a great risk of an electrical fire.

Do like Torque1st said: use the color of the wires coming out of the module.

On the connector with 2 wires:
Hook the white one up to 12v while cranking - the S wire at the solenoid is a good choice. (This retards the timing while starting the engine.)
Hook the red one up to 12V with key on - the electric choke wire is a good one , if you have an electric choke.

Leave the other module harness wires alone.

The only other wires you should hook up, if you have the harness from the donor truck, is the 6V to the coil - the wire that originally went to your old points coil needs to go here.

It is that simple to do, and the possibility of an electrical fire justifies the extra work in starting the job over, from scratch if necessary.

 

We'll it won't run wired the other way. I will take the module back to Auto Zone and see if I can convince them to exchange it for me, even though it tests good. I will reverse the White and Red wires and see if she runs. It will have to wait till next weekend. I am going out of town for work - Oh Pooh!

 

Don't haywire this, you will regret it later... Get it right!