Currently been wroking for a couple of weeks on this boat. Haverelaced and rechecked head gasket, new rotor, points, cap....new heat exchanger, new plugs and wires and rebuilt the carb (merc 2bbl - two screw rochester). Every time that I have retuned the engine ( reset idle, started reset on carb screws and cleaned the plugs), I have gotten it started and it has run like a dream (out of water with fake a lake). This is the same one that when I put it in the water, it ran for a while and then stalled in idle, out of gear and was impossible to start. Compression on all four cynlinders is okay - not stellar - on the bottom side of within limits. Problem I am having is that after a couple of starts, it winds up dying at idle when it starts to run rough (doesn't matter if it cold or not). I have not checked the fuel pressure however the pressure line out of the pump to the top of the carb only gives me about 1 psi. I was thinking that the carb needs to be replaced because even after rebuilding, I can't seem to get the mixture right and I am continually fouling the plugs (lots of carbon buildup over very little time). Need some help on this one !!!! - (Could be the exhaust flappers ? Fuel pump ? Carb ?)
