i have a simplicity 3415h it runs great untill it gets hot sometimes, then it starts to run rough misfires pops sputters. i adjusted the points and the one screw on the carb nothing helps. i had this happen one other time and i shut it down let it cool and it was alright this time nothing helps. this is a 1972 model briggs & stratton type 0126-01

vic, May 2013