I have a yamaha 200e that sat in my barn for 4 years. ran when the guy parked it. I went out, put some gas in it, and pulled the pull starter. It idled for about a minute then died when I gave it gas. I started it a few more times, same thing. now, a month later, I cant even get it to start. I dont know whats wrong, but I want to get it running. where do I start? what should I do?