Skip to 1:56 to see the carburetor being rebuilt.
Also remember when rebuilding, cleaning is just as important, if not more. Carb cleaner basically gets shot in all of the tubes and orifices in the carburetor using the straw. Other videos on Youtube as well as one of mine go into more cleaning detail.
In this video, I show you how to completely rebuild a Tecumseh Carburetor. I go into more detail as to replace the orings in the emulsion tube. I should have changed the primer bulb as well. The machine always ran well, but I decided to rebuild it later when winterizing sine it hadn't been done upon cleaning. I didn't necessarily notice a great deal of a difference in performance, but it stopped my gas leak problem from the bowl gasket being old and brittle.

This was my first howto video video, so I may have been a little slow at presenting the information. It's best for someone who hasn't done this before.
I believe the bowl nut was actually a half inch and not a 13 mm.

The engine starts on the first pull every time.