1978 johnson 85hp fuel problem

[monte100727]

I have a 1978 johnson 85hp that runs out of fuel at 3/4 to wot, I started with rebuilding the carbs as this motor set for over two years, also installed four new coils, new fuel pump,and water pump kit, when I did the fuel pump I also replaced all fuel lines from tank to motor and retaped through hull, tank,and seperator fittings, I had a holley red carureted fuel pump laying around so I installed it between tank and seperator and removed bulb and put new bulb in toolbox for back up.The mootor now starte good idles out good but at 3/4 to full throttle the carbs will start running drie so I have toturn on electrical pump to keep up or back off the throttle a little, I didnt do anything with the tank vent as I over filled it once and had gas coming out of vent, assumed it was O.k. any body have any thoughts?

 

[James R]

Re: 1978 johnson 85hp fuel problem

The more junk you install between the tank and the motor fuel pump can only result in a restricted flow. I suggest you clean it up and get back to the simple bulb and line system.Be sure that the bulb is in the right direction and if you have an inline filter in the fuel system make sure that the arrow points in the right direction. There is a check valve in both of those items that will allow limited flow but not enough for high RPM.