Does anyone know how to rebuild or take apart the actuator that closes the flap?
thanks!

Air actuator for muffler?????

If so, I rebuilt/replaced the O rings in one of mine that was leaking. The ends were just threaded on caps. They look like they are one piece, but the ends do come off.

Yes the air actuator for the muffler... I did try to turn the ends but all they did was turn and didn't seem to loosen. Not sure what kind they are as i bought them used.