I own a 2001 60 hp 4 stroke mercury motor....Boat was idiling and not running right for 2 weeks..So today i rebuilt carbs and well now it starts right up idles rough still but once you give it throttle with choke or stick it stalls or backfires? Won't run at high idle for anything. Anything else i should be checking...I do have new fuel in tank,new fuel filter and still not right?