I posted this once before under STX38 Running Trouble..I have an STX38 with a black deck. My mower starts fine and runs perfect except that once I go over half throttle the engine runs like it wants to blow up. I checked the carb (someone mentioned the butterfly valve). Seems fine. Then I checked the linkage for the governor (Another gentleman suggested this). It seems okay. Unless I am missing something on the linkage thing. Up to know if anyone has a suggestion please do not hesitate to tell me. If there is nothing up to now, then the last thing suggested was an inner governor issue. Is there anywhere I can get a schematic or drawing or help going through this? I am not relying on this mower for mowing so I kind of want to do this myself..Any input is greatly appreciated..