I have been buying a few of the older Lawnboys, which were 2 cycle. I have learned to clean carburetor, but always had problems re-installing carburetor. Could do it, but very tricky getting air vane through hole, and getting the two long screws into the heat plate.
The other day, it dawned on me that if I took the self-propelled cover off the unit, it was such a very simple installation! No problems at all, and did it "with ease". I always had a little problem before, but now....no problem at all. Guess I learned something each day.
Working on my Lawnboys is a lot of fun, and I wish I had started a few years ago.