Electrical Gremlin with an '83 2.8L duraspark conversion truck

[Fords4Us]

It's been a long time since I've posted. I did a Duraspark conversion on my truck about 8 years ago, and it ran well for many years after that. Then I started having an odd, sporadic electrical gremlin which I could never track down. I ended up parking the Ranger for a few years, figured I'd end up coming back to it and solving the problem. Well, it turns out that time is now. I'd like to get the Ranger back in service. So here's a description of the issue. Maybe someone here can help me figure it out.

The pattern always plays out like this:
1. I'm driving up a big hill, generally in either 2nd or 3rd gear, so my RPMs are relatively high as the engine is under considerable load.
2. For whatever reason, I need to shift, so I put in the clutch. <BOOM!> The engine stalls, and I lose all electrical.
3. I usually have enough momentum to try to restart the engine by popping the clutch. I can feel the vacuum of the engine pulling in fuel to try to restart, but there's no ignition. If I'm stopped and try to crank the engine over, I don't even have my starter.
4. And here's the kicker - if I wait just a minute or two, I can restart and drive away like nothing happened. The problem doesn't reappear until I'm driving up some other hill.

It doesn't happen on every hill, but it happens often enough that the truck became unreliable, which is why we parked it. My hunch is that either the distributor or ignition module is overheating, and temporarily failing. I know distributors do eventually burn out, and I've read that the ignition modules also need to be replaced every few years of regular driving. I can go ahead and replace both, but that feels like a shotgun approach. Can anyone give me any solid ideas of specifically what might be happening? As always, thanks in advance!

 

[franklin2]

If it won't even crank over, then it's not the ignition. It will be a problem farther up the line where the main power comes in.

You lose ignition and the starter doesn't work, the common point for both of those is the ignition switch.

If your 83 is like my 84, the main power that feeds the electrical starts at the battery + terminal. There is a fat wire that runs from there across the front of the radiator over to the driver's side. It comes around, picks up the feed from the alternator, and then goes inside were it splits to the ignition switch and the power all the time part of the fuse box.

This is a intermittent problem so it will be hard to find. If you visually go over the main power feed wiring and do not find any problems, you are going to have to rig a testlight at various places, and then just drive it. If the testlight goes out when the truck stalls, you know the problem is behind the testlight. Then you can look that part of the wiring over again, or move the testlight farther upstream and try again.

 

[franklin2]

Correction; The main power feed starts at the large terminal on the starter solenoid that goes to the battery +. You will have the very large starter wire on the large stud on the solenoid, and then a smaller fat wire on the same terminal that runs forward and around the front of the radiator.

 

[Fords4Us]

Thanks for your suggestions. I'll check those lines and rig up a test light if needed. I was trying to figure out how to test where on the circuit it might be; this is an elegant solution. Thanks again! I might just finally get this resolved without pulling all my hair out!