ORIGINAL: Tony Iannucelli
Just maybe to help out a bit... I recently changed a ring on an O.S.61SF, and broke it. It moved off the key tab of the piston when I tried to reinstall it into the sleeve, and the result was two pieces in my hand. I figured no problem, went on the Tower web page and discovered I had to cough up $27 to get a new ring, shipping included ($5). Ouch! You can be sure I'll be careful next time, and would recommend the same to you. Be sure the ring stays on the key in the piston if there is a key.
A second 61SF I have has a frozen ring. I've soaked it in acetone and mystery oil. Heat, cold, both, no luck. Any ideas guys?
Regarding break-in, just running a bit rich should do the trick along with varying the throttle while flying. These are O.S. engines... the reason we pay a premium is because the tolerances are what they are. These are my opinions by the way, and are only opinions. Don't try to confuse me with your opinions, or worse, the facts.
By stuck are you saying it is stuck in the ring groove of the piston or the piston and ring are stuck in the cylinder?? If it's stuck in just the piston and the piston is in your hand just drop everything in Liquid Wrench for a few days then use heat. If the piston/ring are stuck inside the engine and you can't remove it then {this will sound silly} put some Olive Oil in the cylinder and heat the engine up to about 400 degrees in the oven for a while. Pull it out and get a prop tightened onto the crank and chuck up the engine in a vise then try turning it over.