I have a 1976 f-250 with the duraspark ignition setup. I replaced my valve head gaskets and the fuse for the dome lamp over the weekend and now i cant get it to start!

I checked the ignition module and it checked out ok. I checked all of the coil wiring and distributor position sensor wiring and all checked with the proper continuity and voltage. Checked the coil and resistance checked out ok as well. I have only had thentruck for a few months. The positive side of the coil has never been connected to anything and it has run fine. Maybe is is because the prior owner put on a 12 volt coil....Anyways

Here is the only thing i could find...when i check the voltage to the coil when key is in the run position it only read 1.0 volts. When i unplug the wires to the distributor then i get 12 volts at the coil. No spark from the distributor or coil...any ideas?

 

By the distributor position wire do you mean the pickup coil in the distributor?

 

That is correct. I read resistance across the distributor pickup an it was around 640 ohms

 

If the positive side of the coil weren't connected to anything, there would be no voltage, and it certainly wouldn't run ...