When you said that you cleaned the carb, did you remove the float bowl and clean the needle valve and seat? Did you clean the jets? Don't forget, if you remove the adjustment needles to count the number of turns to completely closed, write down the number, remove for cleaning, reinstall to closed, open the correct number of turns. I don't know that particular engine but some of these now have cover screws over the adjustment screws. You should be able to get a manual at any Sears Service Center and your closest store should be able to tell you where that is.