Can this carb be rebuilt? Cant keep it running. Carb has been off and cleaned several times by running cleaner thru all jets ,wire thru ports. It will run only at low speed if the throttle plate is in choke posistion, as soon as you let it have air by opening the plate it will stall. The engine also surges, the governor is constantly trying to compansate.i have sprayed cleaner around the carb while it is trying to run but no change in performance. Am i going in the right direction by carberation? And if i am, the carb drawings im looking at from toro dont seem to have valve seats. Will a carb kit for $50 help this carb or do i need to buy a new one. The mower is an oldy but goody but the carb costs $250.i need some advise as my patiance wears thin.