Why do you think it's ignition related ? Sounds like it could just as well be a carb issue. I would also avise verifying your grounds, voltages and bulkhead connections. Going to need a bit more info wink beer

BTW: I did have a pickup coil wire break internally years ago, I assume it was from the constant flexing it was subjected to by the vacuum advance. It was a fun one to find biggrin
Another was an elect Ign conversion that had the control box mis-wired to the wrong side of the ballast so it was only seeing about 8V. it was an intermittent that drove several shops into giving up. The owner paid me and said he wasn't convinced it was fixed. That was 20 years ago. I still ask him how's the AAR starting stirthepot LOL popcorn

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