+1 Moe...sure sounds like a clogged "hidden filter" if it takes that long to recover. A sure test of fuel flow would be to attach a clear hose to the bowl drain nipple and open the screw to see what kind of flow you get (into an appropriate container, of course).

A positive attitude may not solve all your problems, but it will annoy enough people to make it worth the effort. Herm Albright (1876 - 1944)