I have a evolution .46 engine that runs great
after I fly for awhile it will not return to and idle or shut off
I have to keep flying the plane till I run it out of fuel
It wont idle down slow enough to land
I even adjusted my servo travel in flight
I think it is getting air from some where else even when the barrel is closed on the carb

any help would be great

thanks john

Sounds like an air leak. Check the bolt that holds the carburetor to the crankcase. check the head bolts. Check the backplate bolts. Sometimes air leaks in thru the front bearing. This one is harder to diagnose. you have to replace the bearing to fix that air leak.