After running for about 15 minutes or so it starts missing like it isn't getting enough fuel. At the same time it starts to shoot flames out of the muffler. I pump the fuel bulb and it fixes the problem for only a little bit. As long as I am constantly pumping the bulb it runs fine. It doesn't do it every trip, but it is starting to happen more frequently now. The motor is an 09 with only 25 hours on it. I already checked for the obvious problems like the vent on the tank and loose hose connections and that is not the problem. What can I do to fix this?

It is a 36hp Briggs. Thanks for the help.

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