Tecumseh used that carb on the their four stroke lawn mowers, edgers, etc as far back as I can remember. I began working at my uncle's lawn mower shop starting around 1965 and they were using it at that point. It works essentially the same as the Walbro but has NO pump. It simply uses gravity feed to provide fuel to regulating side of the carb. All of the ones I have worked on in my career had a metering needle in the center of the carb body actuated by the diaphragm. The Walbro uses a rocker to transfer the diaphragm motion to the needle but that's about the only difference in the metering. I would think one could use a separate pump with this carb and have the same results as a walbro. Best of luck with the conversion and Happy Flying.