ORIGINAL: KitBuilder
What are you calling the muffler.... and what are you calling the silencer? This should model should have a bolt throug the center lengthwise with a nut at the front end correct? Are ou saying the back end is rotating on the fixed portion attached to the engine? If it's not tight you could be having back pressuer issues and that could cause the flameouts. Are the nut or threads stripped on the long rod running through it lengthwise?
OK I stand corrected. it's the rear portion. it is loose enough so that the exhaust port will rotate 180. I didn't try to loosen it. It feels like a car start housing bolt when you can't get it apart. I'm certain that if I try to loosen it the screw shaft will snap. Guess the best thing to do is buy a new muffler.