JimandJacki Cariolano

Hello to the group, I am working on a 96 timber wolf. Runs great until it gets good and warm then starts missing and puffs smoke and dies. Plug then is black and sooty. Clean plug and let it cool and then it runs fine again until it gets warm. Engine has decent compression, carb it clean. What am I missing?

I had a lot of trouble getting a 2001 LT F250F running. It seems that they are sensitive to the gas around here so using ethanol free gas is a start also, the carb must be shiny clean and make sure that you check and adjust the valve clearance