the engine is inside actually so cold is not a probelm. i am planning on trying opjose advice tomorrow. haven't been tot he shop today.

He doesn't say the engine is in a different plane, he says a friend gave him the engine, I assumed he meant not on a plane. Check the case for leaks or a warped backplate, check the liner like OPJOSE says. If it just pops on a prime, it would have nothing to do with tank, lines or carb. If the engine is aspirating fuel properly, it should run on a prime until the fuel in the case is exhausted.

well guys i finally got a chance to take that engine apart and i found that the top of the piston was pitted pretty bad and the ring was totally ceized in that slot on the side of the piston. i will have to pry it out of there somehow. also there is an indent on the head where it seemed the piston was hitting. and that seems a little pitted too. did some reseach on where the engine actually came from and it was bought from a guy on rc groups and he said that he was in the middle of breakin it in and then decided to sell it "yeah, i wonder why" he said it worked great but i guess thats why we couldn't get it going........or is it? wonder what you guys think or how this happened..........by the way the top of the piston is really blackened.