Thank you all very much for your inputs. I am guilty as charged: knowing fully well that Duke Fox designed the Eagle III to run on FAI fuel only and that Fox motors (with ring) MUST go through lengthy and controlled break-in periods. It is my understanding that Mr. Fox made a conscious business decision/prediction that nitro would be hard to come by. I bought the engine some years ago but have not run it until recently.

To opine one of own, I have owned K&B, Fuji, HB, Fox, Royal, Super Tigre, OS, Rossi, Thunder Tiger, and MVVS engines, and by far Super Tigre has the metallurgy down to an art. I have replaced rings, bearings, rebuilt carburetors, and repaired busted mufflers, etc. I have done nothing to the Super Tigre engines (3). My HB, OS and Super Tigre engines suffer none to little damage due to deadstick, or crashes. I can not say the same for other brands. I deduce that those engines that don't quit in the air and don't idle well (due to insufficient break-in) will lead to mishaps. I have replaced rings and bearings in my HB and OS engines. What impresses me the most is my oldest engine, a .60 (not .61) Super Tigre, has not lost its compression thru countless flights and years in service. I can also honestly say that every single one of the engines, regardless of brand, that I own has started and run right out of the box with some needle tweaking.

Heeding your advice, I will send the Eagle III back to Fox for repair. To answer Sport_Pilot's question, as a new engine the Eagle III did not idle well due to my neglect to break it in properly. Every one of the 8 to 10 flights I had with it resulted in a deadstick. My Fox 40 ABC did very well as a new engine. Since I treat all engine brands equally, i.e. not giving the special care and attention to the ringed Fox, my next engine purchase will be a Super Tigre.