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Do you leave gasoline in the carburetors when engine sits for prolonged periods of time ?-------Sounds like a float valve is stuck.-------Possibly look
If you do not know how old the water pump impeller is you should install a new one.
Orange wires going to the correct coil ?
From your link: You need either OMC 250212 or OMC 250213, depending on hose size. 250212 fits 8MM hose, 250213 fits 9.5MM hose.
Remove the carb and check it carefully for loose fuel line connections- the needle valve also might not be seating properly and is causing flooding.