This is probably a stupid question but is a 2001 5.7 Mercuiser carburated engine with Alpha one sterndrive a "coolant" model or a "raw water" model. I see in the manual that both have raw water referenced. How does one tell the difference? I'm trying to determine the locations of the drain plugs on my engine to remove sea water prior to winter storage and there is a difference between the two in terms of number and location of the plugs.