I have a 89 3.7litre mercuiser 4 cyl that wont start. Started bogging down as if starving for fuel...i replaced the fuel filter and it ran good for a while....then it stalled and will not start...I'm thinking fuel pump but they say its pretty rare...any suggestings? Also, anyone know whether this is a Ford or Chev engine it seems pretty rare as most 165 hp mercs are 6 cyl as opposed to 4?