I thought I would just check the spark again; folks told me I would not be able to see a spark in daylight conditions. So, one evening, I pulled the conenctions from #1 cylinder. No spark from the lead to the engine crankcase.
So, I decided to check the other wires to see if *anything* was firing when the entine was on the #2 cylinder compression stroke.
Discovered that #2 cylinder (both upper and lower) were sparking strongly when the impulse coupler snapped. So, the engine was firing 90 degrees off - 2-4-1-3 instead of 1-3-2-4.
I talked with the mag shop and some builders on the Zenith and EAA forums, and everyeone suggested pulling the mags and retiming them. Called it a day.
