I got a 2nd Hand Nova Rossi .21CC Buggy engine and this engine is my first engine ever. This engine has 4 needles on it (low, high, idle and im not sure about the other one) I put the set-up as 4 turns for high and 1 1/2 turns for the low, made the four unknown needle flush as that is what I got told. I started it and it went up to 340F and than stalled

Im new to this whole thing and am not quite sure what to do now.
Cheers