I bought this engine new about 10 years ago and have flown it hundreds of times on my hanger 9 twist. Always prime right up and start with one flip. Always ran it on the rich side (like to see some smoke from omega 15%) New set of Boca stainless sealed bearings about 5 years ago still without play and new piston ring. . I fly this plane almost daily in the good months. Got it out and as usual prime right up and start on first flip. Now won't accelerate, just pops and stops when you give it throttle. Ran perfectly the day before. Checked tank, changed fuel lines. New O ring on needle valve. New glow plug. Check muffler pressure for clog. Richened it up nope! Leaned it out nope! Still will start right up and idle just like always but will not leave idle. Acts like it's too rich but it's not.
Anybody got any ideas or experience with this type of problem.