I have this engine for about 10 months. I initially had it mounted on a World Model P-51 and ran it for about few times until it dead stick on me and subsequently crashed my P-51. After the crash, I just left it along until yesterday when I put it on a test stand and try to start it again. After I fuel it up, it started with just couple of turns. It ran at a very high RPM. I check the throttle and it was at quarter open. I was somewhat surprised on why it ran so hot with so little throttle opening. When I closed the throttle, it did not kill the engine. The engine ran consistently at about 4,000 RPM. When I open to 1/8 throttle, the engine hesitated and I could feel the fuel spread out of the carburetor, the RPM dropped to 3,000 and picked up to about 6,000 RPM. I could see big bubbles in the fuel line between the fuel pump and the carburetor. The only way I could kill the engine is to pinch the fuel line and that took about 30 second before it die on me.

I had been flying for about a year now. I own OS, Revolution, Zenoah, ASP and 3 YS engines and never had this happen.

Your input is greatly appreciated.

Gary