I have a Turf racer HP w/ Kaw. Fh580V 19 HP. Started hunting at idle last week- cleared up for a couple days and back to surging. Filters & plugs have been changed, carb cleaned - Found yesterday the plug on top of carb, in front of limiter was missing and sucking air. cover w/ finger runs like a champ. Install new plug w/ small bead of silicone on and let set up and is surging @ idle today. Ready to replace the carb! Any input? Thanks!