I have a tower hobbies .46. I started it up once, and it ran decently well. However, it will not start up again. Even when I prime the engine, i cannot get any fuel into the fuel line. Fuel is getting into my exhaust too. I know this is a newbie problem. I also think it has something to do with the needle valve. Any suggestions on adjusting it? It may also be flooded. I'm not sure about any of it. Any suggestions would be appreciated.