The most important part of keeping the exhaust diverter on a muffler is to start off with a clean surface, free of oil, and a clean exhaust diverter, AND, of course, to get the right size for your engine. You don't need adhesive, and most will melt or de-bond with the heat.

I have Dubro exhaust diverters on all of my planes, not a one has come off at any time. This is because I did as I suggested, AND used two zip ties in the slots provided. You have to pull the zip ties tight, use a pair of pliers then trim them close. If you break one by pulling to tight, well, remove it and put a new one on. Use the small size that come with the diverter because they are the most flexible and will wrap completely around without having gaps. Again, if you break one, remember how much you pulled it together and put another one on but not quite as tight (common sense stuff).

You only need two zip ties and put them in the spots shown by the manufacturer. I have only used Dubro and they all come with two slots or spots for the zip ties.

The key thing here is to make sure your muffler exhaust port is clean. Use alcohol to get ALL of the oil off and wipe it dry. Check it to make sure oil did not dribble back out on the surface. If it did, clean it more. Depending on the muffler (OS 70 AX for instance has OS Power Box mufflers that come apart), you can disassemble the muffler, clean it really well, then install the deflector first, then put it back together.

CGr.