I have a 1979 Johnson 35hp (35el79a that I recently transplanted to my aluminum boat from a donor boat. After re-wiring the engine, controls, and cleaning the carb it fired up with half a turn. But, I didn't see any water coming out anywhere, just some smoke. I only ran it for about 10 seconds, In fear of over heating or something. Does the thermostat open at a certain temp. like a car, or does it constantly pump water? Any help would be greatly appreciated.