repeated loose muffler (came with the new pitts style). tried red locktite, didn't help. finally drilled out the threads in the muffler and this gave several flights before loosening. problem now: threads in one side are gone in the jug. will a helicoil hold???? help! like the engine except for this problem.

TR,

Sorry I am not your tech rep for the US Engines, but I have had the same problem. The helicoil will solve your thread damage problem. Do it on both sides. To prevent the screws backing out again, drill the heads and safety wire them. I did this some years back and have never had the loose muffler problem since.

Bedford

thanks for the info! the socket head screws are countersunk very deep into the muffler.........can't wire them. any other ideas?

TR,

If they are countersunk then no. If they are flat on the bottom of the head then you might be able to space them out enough to wire them. That, of course, may cause you fit problems with the firewall and require a slightly longer screw.

Good luck!

Bedford