I recently purchased a 30% carden extra 300 with what appears to be a sachs 4.2. Being new to gas I recurted help getting the engine ready to fly. anyway the engine starts great cold, but after its run a while and shut down it will not start back up until it has completely cooled down. I've changed plugs, battery,and switch, still the same problem. If I'm missing something please let me know.

Thanks in advance.
Tim