I read the thread about the bad switch also. When I had the plane on the bench, I tried the switch I had in the plane, 2 others, and several battery packs. All worked fine.

I thought about heat as well. I don't have a temp. gun, but I had about 20 min. between flights, so the engine should have been cool before restarting. Also, the engine didn't sag or give any indications of overheating during the flights.

When I first started noticing the problem, I was seing it in flight, so I thought it had to do with airflow affecting the carb. I tried the tube over the carb. pump vent with fuel tubing into the fuse idea. No help. I also tried a velocity stack in every orientation with no luck.

After Gilcon's post I was trying to remember if I had the problems when I was using non-synthetic oil for break-in. I'm pretty sure I didn't, so I'm going to switch back to non-synthetic and see if I get the same issues.

I'll let you know how it goes.

Ben