I have a service manual on the
boat and will get you a drawing of that
pump today when I go there. If I am not mistaken, that is just a plain jane
diaphragm pump operated by a lever driven by a camshaft lobe. Two screws holding it on the
engine. Same system used on most engines since about 100 BC. Sometimes you may need to rotate the engine by hand a quarter turn to take pressure off the lever and maek
removal easier.