Originally posted by ED STEFAN
Paul,
3/4 turn seems to be a lot, even considering a 20 deg temp shift. To be on the safe side, you might want to check for loose screws in back-plate, carb, etc.. Could be sucking air. What type engine is this, and is it broken in?
It is a OS LA40. I am/was in the process of breaking it in (4 tankfuls through engine)