I just bought a 1967 Evinrude 3 hp lightwin. I put in new plugs, changed the fuel filter, and put in fresh 50/1 gas mix. I also put Sea Foam in the gas. It starts and runs at slow speed, but when I advance the throttle it does not speed up. It actually begins to run rough. If I pull the throttle back it will smooth out. Sometimes it will actually rev up a little if I back off of the throttle even more, but any advance past "start" speed and I get no increase in speed. I've played with the rich/lean dial but it doesn't seem to do have any effect on the problem. Why won't this little motor rev up to full speed when the throttle level is advanced?
Thanks.
Thanks.
