I got the airplane out on the ramp today in the bright sunlight. With all that light I could definitely see the magnet just barely touching at least 1 leg of the lower mag. So I will reset the gap on both mags. Since I checked everything else possible, that just has to be the cause of the problems I've been experiencing with the primary ignition.
Interestingly, we did the following prior to me finding that:
1. Removed the ground from the top mag and ran the engine. Turned off the secondary at 2,300 RPM. Engine actually ran OK at that RPM, with a slight miss every now and then. Back the throttle down to 1,700 and it ran rough and finally quit.
2. Re-attached the top mag ground, and removed the bottom mag ground. The exact same results as above.
3. Re-attached both mag grounds. Ran the engine with both primary and secondary, but leaned the mixture. When I turned off the secondary the primary ran just as it did in 1 and 2 above.
I'm a little puzzled why the engine would run on the primary at higher RPMs. I would think it would run equally bad no matter the RPM, if the magnet is contacting the mag(s).
