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73 Johnson Low Speed great Rough and weak open throttle

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Walap42

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I have a '73 20R73A Johnson. I boiled out the carb and now it has a GREAT low speed. I have decent mid range on throttle (tiller) but when I open it up there is a brief moment that sounds as it she'll take off but, then it bogs and runs rough. I never noticed before but, today my hand contacted the intake manifold while under load and it was icy cold. Maybe that says something. Any help appreciated. Minnesota summers are too short be fixing when I should be going.
 
Any liquid that evaporates needs HEAT and that heat comes from the carburetor body and intake manifold.-----Simply put that is the basic theory of a refrigerator.
 
Thanks for feed back. I guess 6th time is the charm. I found a carb kit on line and it gave mea few necessary pieces I did not have before. Since I had a high speed issue, I boiled out the carb bowl casting where the high speed jet is located, and then replaced a hardware store washer with the right one from the kit. Goes like a scalded cat now. Funny how the right part and a bit more attention to cleanliness can make a difference.
 
My guess is that there was a restriction in main jet causing fuel deprivation. Common mistake with carb cleaning jobs....don't feel bad, you fixed it. MN is an ethanol mandated state....one of 7. Why? We got tons of ethanol corn fields. Keep ethanol away from your collector car/truck, small engines, and outboards. If gas pump didn't have a dedicated hose for non oxy, then either make sure last purchase was non oxy, or pump a gallon first into your newer car or truck. I drive a 1974 Chev pickup....it gets alcohol free fuel. So then I keep a gallon can so I can pump out the ethanol first. Then I use that fuel in the newer car the wife drives.......life's tough enough, I don't need ethanol to make matters worse. I do marine and small engine repair here at home. Keep non oxy clear in several 265 gallon tanks. It lasts for 10 years WITHOUT stabilizer. Add Stabil and it will keep 15 years or more. Just took delivery of 1400 gallons in April. Paid $2 a gallon.
 
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We finally have a vendor nearby that sells non-oxygenated high test. What is really peculiar about the ethanol push is, it was allegedly an attempt to reduce carbon emissions. Those who are honest enough will admit that it does not reduce carbon emissions as hoped. It takes carbon powered facilities to create a fuel that provides fewer BTUs than gasoline thereby reducing available power to the vehicle, reducing the potential for better mileage, improved vehicle engineering not withstanding. I noticed on a rip to Texas years ago that my fuel efficiency improved when I left the corn fed states as I headed South. I was getting 22 to 24 mpg on alchy mix and over 28 or pure regular. So, we are burning more fuel to go the same miles than we would on good old "gasalone".
 
Right on brother. The whole concept was created to support certain farmers and "renewable energy". It costs more to produce than pure petrol and a very limited storage life. It is also deadly to rubber compositions and many synthetics.....crank seals, tubing and hoses, sound suppressing foams used in motor cowlings, some wire insulations, and encourages oxidation and deterioration on many alloys of aluminum and magnesium. As a result, the FAA has made it illegal to use in airplanes and helicopters......etc.
 
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