[gss036]

I think you are picking up junk in your fuel pick up in the tank. That was exactly the same way mine was acting/running last year or so and I ended up replacing the tank. I could not believe all the junk I had in the bottom of the tank. Try blowing back through the fuel line from the primer bulb, (probably have to take the bulb off)if you can a little while and then the problems reoccurs, then you have a problem w/junk in the tank. Some tanks have a filter attached to the pick up tube. The Racor filter does a really good job of stopping the junk from getting into your engine lines up stream. Most fuel pick up tubes just unscrew from the tank. Lots of pro and cons on anti-siphon valves. My old tank did not have one, but the new ones does.I used to be able to siphon off gas for the lawn mower, but now w/the anti-siphon valve you have to manually pump it out w/the primer bulb.