update on my evo 100nx. after two weeks and a gallon of fuel, i got frustrated. but one thing i did notice was almost every time i primed the engine, as soon as i took my finger off the carb, i would notice the fuel in the line would immediately start flowing back to the fuel tank. i checked and the tank sits level to the carb. at this point, we figured that i had an air leak somewhere. i pulled the fuel tank, put a new one in, all new plumbing, tore apart the carb, cleaned everything out, new fuel lines, sealed the carb as ive heard there were problems with the seals on them. sealed the exhaust. took it out yesterday and set it really rich, got it started, tuned it rich and decided it was now or never. it was going home a whole plane, or in a garbage bag. it flew great! a full flight, no stalls. sounded great! checked temp and i could put my hand on it and not burn myself. i dont know what part fixed it, but i fully think it was sealing the carb. let me tell you, when i fine tune this, and get a bigger prob, this engine is going to be a beast!! i hope this helps anyone else that has an evo.