oh ok so you mean it might not be tuned correctly? after the first couple of trys i dont give it gas at all just prime the engine then try to start it. after i tryu and start it for a couple of mins and nothing happening i check the glow plugmake sure it lights up put it back then prime the engine with alittle more fuel. i also play with the throttle alittle bit. i just had it running today for half a tank. the thing is also that sometimes it just stalls out and then it wont start again maybe the engine is to hot i don tknow but thats another thing thats a problem i use it maybe about half a tank then it stall and wont start up again. i will get the check valve.