Upon further review, I think it may be some sort of pump. What looks like a carburetor is some sort of metering device for flow. I thought of the possibility of it being a diesel, but don't see any water intake or discharge, unless that is a tub below the "exhaust, and is a water intake, and and some how exits with the exhaust. I don't see any signs of heat from any kind of ignition. The markings on the side of the mounting lug are interesting. Similar to markings like you would see on a foreign built carburetor like a Bing. Definitely a curiosity!
Type at you later,
Dan McEntee