In Reply to: 2N Dilema posted by Del Huebner on June 26, 2018 at 12:14:01:
Some time ago, my '48 N did this. What I found was that the condenser, added during 12v conv. from former owner, had an open back. When it got hot, the spring would expand and touch the cowling. I removed condenser and added a pc of cardboard behind it. Never did it again. Granted that may not have been issue, could have been carb had some trash in porting, but all is well.