Engine Hard to restart after it cooling down. You running at 250F is running lean. When the engine cools it change a bit. Your trying to start lean. Richen you HSN by 1/2 turn and try again. Then retune for optimum performance. Cold engine richen it out and retune, like running in afternoon @ 250F, let it cool till tomorrow, 1/2 turn on HSN then retune for the day!!