Electrical Issues Maybe Pick-up coil?

[Bob]

Electrical issues are no fun for me. Was never very good with the stuff...
Any help will be appreciated. If I can't resolve soon will take to shop and get it over with.

1st off seemed like truck was getting harder to start lately. Then Saturday I went to shut it off and it would not. Not dieseling just the switch wouldn't kill it. Tried going back and forth with the key and to accesories and wouldn't shut down so I stalled it. Go about my business for about a half hour 45 min and come out and the truck won't start. Rolled over fine and checked and no spark. So I figure the ignition switch was bad and get my buddy to run me home to steal the switch out of my 71... slap it in and still no good. Run around looking for an ignition module and nobody had one. Got one next day and still no spark. Put new coil in. Nothing yet.

Anyone know what sort of Voltage I should have at the coil+ side with the ignition switch on but not rolling the engine over? The truck has an ignition module and I'm wondering if it has to be rolling over to get voltage at the coil? (I was getting zero with swtch off and only 0.1V with switch on. I would think 12V -ish should be there when switch is on but maybe module provides juice only when rolling over?)

Something had to keep voltage to my coil (or to the ignition module then coil) even when the key was off. Could that something maybe have been the switch and could the switch in that state have fried my Petronix pick-up coil? My thought is to put the old ignition switch in and see if I have voltage when switch is both off and on. Then figured with swapped out switch should have normal function and that would've sort of proved the bad switch thought. Now thinking maybe clip a hot wire from battery to coil+ and try firing it up. If it runs then problem is from coil back to key and anything in between. If it doesn't then pick-up coil in distributor is bad. Right?

With current ignition switch I have no juice to coil when off. (And not much when on either... ) Still need to look at the switch that was in it when it wouldn't shut down and see if it shows any juice to coil when off.

Any thoughts or help appreciated...
Thanks,
Bob

[Bob]

It's a 72 F250 and it's cured...!!!

copy my 72 f250.jpg

It was driving me nuts and it had stopped raining so I went home at lunch time to check it out some more. I took a jumper wire from the battery to the coil and tried lighting it up and it wouldn't start / no spark. Removed jumper from battery and wedged my probe into + side of coil and stretched the meter around so I could see it and reach through the window to hit the key. Key on but not rolling motor over was 0 - 0.1 again... Took another voltage reading while rolling it over. 9 V +/- a little due to the pulsing. No voltage with key on unless it happens to land on a pick-up thingy. (technical term)

Soooo... Figured the Petronics pick-up got fried when the ignition switch failed. Swiped the Petronics pick-up out of my 66 and put it in and after a little timing tweaking Voila!! It's back on the road...! Course now the 66 is laid up until my new kit comes in. An I need to get a new ignition switch for my 71... The 71 is waiting on the motor from Survival. Spoke with Barry last week and shouldn't be much longer. Can hardly wait to get that one back running.

[Bob]

Another side note...
When I pulled the Petronix pick-up out the sticker on the side was slightly melted and browned up where it started to shrivel up.