AT THE END OF 5 MINUTES HOW MUCH FUEL DO YOU HAVE LEFT? YOU MIGHT BE ON EMPTY AND AIR IS IN FUEL LINE WHEN YOU PIT.IF SO YOU MAY HAVE TO LEAN IT OUT A BIT JUST TO EXTEND YOUR RUN TIME IF NOT TRY RUNNING MORE FUEL TUBING OR XTRA FUEL FILTER .I HAD SAME PROBLEM JUST RAN XTRA FILTER