460 87E350. 4180C. Had small fire. reworked carb,replaced vac lines. ran rough at Idle for a minute then ran perfect. Learned a few lines were not right tried to resolve but now no spark during crank. Let go of key and one spark when motor winding down. Frusterated and too broke to go to a shop....

 

ah reread post.... May or may not be related to fire.

Maybe more experienced guys will correct me,but sounds like ignition switch . Maybe procedure to check hereabouts somewhere ?
Luck,Ed

 

Either the key switch it self is bad or the while cranking start circuit is faulty. I would suspect the switch is bad.

 

ran into this exact problem when me and some buddies tried to fire up his rebuilt 460 in the 79 half ton we are building. changed just about everything until we found that the underhood ignition wiring harness was no good.

 

if its carb then you have the duraspark 2?, you could use the gm module 4 pin setup, do a seach in this site "duraspark with gm module", its a 4 wire hookup, it will get you on the road, basically bypassing the ford module and key ignition switch,,,may sound complicated but not as complicated as rewiring some burnt stock wiring, the wiring is pretty easy, for now it it would my route, , good luck

 

Yes either your switch or Duraspark module have gone south. Only other thing is bad wiring and with a fire that is possible.

 

During the start position on the ignition switch 12v is fed to the system. When you release the key to the run position reduced voltage is used. I would look at the start end of this beginning with the brown wire on the starter relay in the I position. You can take the control module to NAPA and they will test it for you for free. Don't yank out a bunch of wires, it is almost never the problem. Fully charged battery, dry plugs, functioning choke, one pump of the accelerator (look for gas in the carb) and try to start it.