1971 18hp Evinrude Fastwin

[Swivelhart]

I replaced the coils, condensors, points, rebuilt the carb and have great waterflow from the impellar. When i first take off it seems to run smooth and strong after running full throttle for about 1 minute it starts to choke and sputter and will not run wide open after that. It doesnt stall but acts like its starved for fuel. I do not understand and am quite frustrated. What haven't I done. Anyone else with a similar problem?

 

[crxess]

Re: 1971 18hp Evinrude Fastwin

Aged fuel lines
Fuel pump
Bad primer bulb
Blocked tank vent
Bad fuel pick up in tank.
Air leak anywhere in the fuel system.

When it sputters(loses power) give the bulb a squeeze. If it picks back up the likely culpret is the fuel pump.

 

[Daviet]

Re: 1971 18hp Evinrude Fastwin

When you overhauled the carb, did you remove and clean the high speed jet and passage, and blow it out with compeseed air?