its a yokomo rx .18 engine in a stadium truck and i think its because the front crank bearing leaks air, some people say its suppose to be sealed so no air can leak and some say its suppose to leak air. i blow on the fuel line with my finger over the carb and air come out easily and i sprayed water on the bearing when it was idleing and it sucked it in and stalled the engine. my engine doesnt have a low speed needle and the only way it will run without stalling from lack of fuel is around 4 to 5 turns out on the high speed needle and it runs like crap and sizzles water drops right off the head instantly after about quarter tank, the bearing only has a metal dust cover not a rubber seal so the cause of it too hot and lean sholdnt be an air leak in the bearing because the factory would have put a rubber sealed bearing if its a problem. i have sealed all the possible air leak areas and nothing worked, the engine has about half gallon through it and the piston and sleeve is worn because of the overheating problem im having, it ran ok for about a week and then i started having problems