pitts style muffler will not stay attached! have flown 25 flights with 12 resulting with the muffler loosening up or completely coming off. have tried red permatech thread lock.......replaced the bolts several times (keep losing them). this time i have drilled out the threads in the muffler, used rtv instead of gasket material and red thread lock. i read many posts with the same problem and trying some of the users fixes. wondering what the manufacturer says about all this since they made the dang thing and obviously didn't test it!

TR,

Sometimes the muffler bolts are a hair long, and are bottoming out in the holes before they are really tight. You might want to check that. If so, just shorten them a bit at a time until they no longer bottom out when you tighten them.

Another way to help keep them tight is to insert a piece of monofilament line into the bolt hole and then insert the bolt. It acts just like the nylon insert in a nut.