With the <OS 61 wcII though is the only one I've owned>you want the low end out about 1 turn, the mid range 0.25 turn or closed completely and the high end 1.5 - 1.75 turns open. (According To Which Pipe You Are Using Now)
Poor cooling system can result in engine over heating and a very rough run. This will usually show up with the helicopter running fine in initial hover, but it runs very rough after flying around a little (once it heats up some) Fix this by running the high end and low end a little richer (maybe 1/8 turn)
Settings on that engine could be totally different so set it with extreme caution mind you.
Enya #3 plug I believe works well with this engine.

Fuel, you want to run one that has at least 18% oil in the 15% nitro fuel and 23% oil in the 30% nitro fuels
As my wise ole Dad once said though, try it do not fry it. The ring idea sounds reasonable though....


I would scope out the piston & liner to chk. for large scratches on the side walls. Look for signs of unusual wear-check ring.