Thanks. You guys helped me locate the problem. There is a loose large perforated metal screen inside the muffler rattling around - when intact, goes from one side to the other. It is obvious where it broke loose from when you look inside. I am sure that when it broke loose, it was the cause of the sudden change in the exhaust sound. Although I am tempted to grab it some way and yank it out and keep flying, something tells me it had a purpose more than as a spark arrestor - such as tuning. Since I see no way to repair it, guess I will be forced to spend $1200 for a new muffler to fit my plane. Anyone have thoughts on ripping out the loose piece as long as the exhaust system has no leaks. If anyone now has suggestions that can save me the expense of a new muffler, I would appreciate it.
I took pictures to show the cracked piece as well as my muffler installation. I rattled the cracked piece into the picture - the piece not centered is loose and slides from side to side when I tilt the muffler. I had been unable to attach or insert pictures a few days ago, but I will try again now. If the pictures are not here, it is because I was unable again. I have the picture files showing below as I type this (and the "Remove File" boxes showing) - so it seems when I 'submit' they should go. Note: I just edited to add this note - I do not know how to post pictures.
Thanks,
Dennis
