Some of the older fuel hose is not compatible with ethanol and can delaminate internally causing a blockage. I wold replace the bulb and fuel line since you are having the bulb problem.
Make sure the fuel line isn't pinched anywhere. I had the same problem with my new Seaark and the fuel tank had slid over against the fuel line and was pinching it closed.
2015 Seaark 1872 MV CC Etec-90
Two Helix 12 CHIRP SI's, , MinnKota Riptide ST80/i-pilot Link, Bob's Hydraulic
Bitter Gun Owner