1980's Evinrude 7.5 HP fuel problem and speed.

Hi, this could be a very simple problem if you know the answer I rebuild the carb on the engine because it would not start problem solved, now the problem is it will only run in low speed everything is good until you want to bring up the speed and you get nothing. I am at a dead end I would pull the carb again,but i have no idea if that is the problem, and then what do I fix without any idea whats wrong. any help would be great. Thanks.

Likely running on just 1 cylinder.-----Post your compression numbers.----And does spark jump a gap of 3/8" or more with a test device.----Sparkplugs are not used for that maximum output test.

I want to thank racerone for getting back to me I used a spark tester and got a good spark 3/8 in I did not have a compression tester, but I do not feel that is the problem it seems to be a fuel problem or a fuel adjustment somewhere in the system. It went up to speed then fell off and then start over with the trouble shooting. This thing starts on the first pull, but it runs ruff in slow speed, and then no high speed. Is there an adjustment for the throttle to open up something to allow the speed to increase I am into guessing the problem now. One last guess is their something in side the carb that could be causing this rpm problem. Done guessing.

Perhaps fuel pump diaphragm has a hole in it.----If motor was here it would take no more than 10 / 15 minutes to determine where the issue is.----Good luck with it.