95 350 Magnum

[TKO2013]

So I just purchased a 95 Mariah with a 350 Magnum Merc.. boat runs great. But after an hour of running its very hard to start and have to pump the accelerator to get it going again. Its almost like the float bowls are dry. fuel pump is working well... the coil leads are all attached and fine. takin the carb apart and everything seems clean and fine..
any ideas?
Thanks
one suggestion was to run the blower continuously... because of possable vapour lock.

 

[hystat]

did you ever look down the venturis to see if gas was flowing during hard starts. Flooded and dry symptoms are pretty similar.

I would also pull spark plugs after a run, and see if any water droplets on the plugs indicating failing water shutters, manifold, riser or gasket letting water into combustion chambers.