Tecumseh went through a perverted period of using diaphragm carbs on all sorts of engines 2 and 4 cycle. My opinion is that I would not likely bother with any such engine unless I had a float carb to put on it, or it was something really special. The only good thing to say about it is that the motor likely has very low hours due to people giving up on starting it.
The water tube is better than the pump as the pump impeller may not be readily available. I suspect Eska went to the pumps when they started to use neutral clutches, as there would be no flow in neutral with the prop still.
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