have been working on a fuel starvation issue on my Arctic cat 250 now for several weeks with no results. So far I have rotated the tank 180 degrees, shortened the fuel line to about 6 inches, swapped out petcock and gas lines to 5/16", removed the in-tank filter, and installed a large inline fuel filter.
Here's the problem. After long up hill climbs or long full throttle runs, the gas line runs dry. It's as if there is a vacuum lock or some type of air back pressure that will not let adequate fuel come out of the tank. The fuel will not flow even when I remove the gas cap, but if I disconnect the fuel line from the carburetor, fuel flow is excellent.
I even primed the inline filter to capacity prior to completing my gas line connection, but after about five minutes of riding, the fuel filter was empty and did not refill.