I was given a 1986 trailboss 250. The starter dosen't work, but I am able to pull start it. I have a brand new spark plug and fresh gas. I was able to get it started but it dies soon after. What I have to do to keep it running is literaly blow through the carb vent hose. Also to get it started I have to open the throttle, blow through the hose until I see gas coming out of the carb, with the airbox off, and then pull start it. And keep blowing in the vent hose. Any ideas why this would be? I belive the vent hose is just suppose to hang down?

Thanks

 

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