Hi All I have a 1977 Onan 7.5 MDJE that was running rough. I replaced the primary and secondary fuel filters as well as the cleaning out the catch bowl at the fuel transfer pump, the fuel had evidence of water in it. Everything back together I can't seam to manually pump the transfer pump. There is a lever to manually prime the system but it's dead, zero resistance. Is it supposed to have zero resistance? What am I missing?