My tractor(12 volt converted) that had so little spark ground in the plugs that it barely lit one of the testers. Turns out, the ground for the battery and engine and body(all one) was not good. It got red hot, really, really, really quick. But imagine that, hardly getting 12v or maybe not even at the COIL.
Farmall, Allis Chalmers, F*rd, John Deere, or other? I recently got me a ‘49 Cubbie and went through that whole thing. They came with magneto ignition but someone converted this one to points. First, no spark because the condenser was grounded to the distributor housing. Second, no start because the timing was off just enough to keep it from starting. I’d never worked on something so simple. I thought late-70s to early-90s GM was fairly simple, but even that’s like entering the Matrix compared to the really old stuff.
OP: that cooked ignition coil lead is usually from slipshod grounding. You’re supposed to have two grounds: the bolt-down wire shown in the pic and a strap with a pin that inserts adjacent to the hot and tach pins in the cap. I don’t remember the OEM ones having the strap, but I know I’ve fried some supposed quality aftermarket units that didn’t come with them. Much better luck with coils that supply the redundant ground.
If you have spark and fuel, something should be happening. Like everyone’s said, make sure you have enough spark. Did you make sure you felt compression out of #1 when you set timing, aligned the mark to TDC, and then adjusted? It’s sounding like a possible 180* out, but it shouldn’t be if it was running, and you didn’t make any radical changes or pull the distributor.
What about cranking voltage drop? Is the starter dragging around? A dying starter can easily rob an ignition system of much needed juice. And all your grounds are good? I’d get a ninth plug you have lying around and rest the plug on the engine for ground and spin it over. Also make sure your cap didn’t crack, and if you have aluminum pins, that they’re not totally oxidized or the wires burned or shorting while cranking. This test is best performed at night when you can see spark touching places it’s not supposed to.
