2 OS fs.91 mufflers with worn threads-Problem & fix?
I have two OS fs91's one is old one is II. the old one has gone through two mufflers and now the II HAS JUST DESTROYED ONE. I am sick of buying muffles and now I think they are discontinued. They were tight and the prop is balanced. What do I do now? Is there a M11x.75 helicoil? I've searched and found just a tap. HELP!