Every time I change the oil in my rebuilt 1955 235, after I let the oil set for about six hours in a clear container I notice water at the bottom of the container. The oil isn't murky which would make me assume a bad head gasket. Additionally the coolant level stays the same. The water is clear and not the color of antifreeze. The engine doesn't have a oil filter and the amount of water that is present is less than a pint. The engine runs great so any advice as to whats going on.