I have a "50 F-1 with a 351W and Duraspark II ignition. I followed the wiring diagrams forum members provided but still feel there is a problem because there is a 1 to 3 second delay from the time I turn off the ignition switch until engine stops. This is my wiring scheme and I would appreciate it if anyone sees a problem I need to address.

Wiring Scheme for 351W with Duraspark II ignition
Note: Starter relay(solenoid) references are made looking at relay from front view
Relay Wiring:
Battery cable, One wire alternator bypass wire, and wire to BAT terminal on starter switch are connected to the left terminal of relay.
Main starter cable and 12 gauge starter (on-board solenoid) wire are connected to right terminal of relay.
Wire from relay “S” terminal to starter terminal of ignition switch.
Wire from “I” terminal to the white wire of the two wire connector at the control module.
Control Module Wiring:
Red wire from two wire connector is connected to IGN terminal of ignition switch.
Standard harness is used from distributor to control module following color code.
Green wire from coil harness to green wire of control module four wire connector.
Red/green wire from coil harness to one side of ballast resistor and wire from other side of resistor is connected to IGN terminal of ignition switch.
Misc. Wiring:
Wire from electric radiator fan to on/off switch and another wire from on/off switch to IGN terminal of ignition switch.
Wire from electric choke to IGN terminal of ignition switch.

 

Your resistor bypass wire. You have it connected to one of the large terminals on the starter relay? Take this off and see if the problem goes away. If it does, try hooking it to the "I" terminal of the starter relay.

 

Thanks for helping. The only bypass wire connected to one of the large terminals on the starter relay is from the one wire alternator. My wire from the "I" terminal of the starter relay is connected to the white wire at the two wire connector on the ignition control module.

 

Do you have a small wire running from the alternator to the ignition switch to tell it to charge? And is this the same place the coil + wire is hooked up? If so, then you may need to put a diode in the small wire to the alt to prevent the run-on. As with the other wire, you can take the small wire to the alt off and see if the problem goes away.

 

I guess I am out of my league and don't understand what you mean. I contacted TuffStuff who make this one wire alternator for Fords and they said the only connection required is from the Alternator to the large post of the starter relay which also has the battery conntected to it. I really appreciate your trying.

 

Some of the one wire alternators do have an option to run a trigger wire to make it charge. Otherwise, you might have to "goose" the engine a little bit after you start it to make the one-wire start charging.

For anyone who uses a GM style alternator and have the run-on problem, the alt will feed back some voltage down this small wire and give power to the coil even after you turn the ign switch off.

This feedback from another source could still be your problem. What I would do first is while the engine is running, disconnect the coil + wire. The engine should stop right away. If it does, I would trace the coil + wire back, and find out what it's connected to. If there are other feed wires along with the coil + wire, you could disconnect them individually, and see if this happens to stop the problem. If it did, you could investigate further what that wire feeds.

 

Super input. Thanks.