proper winterizing of 1984 3.0L and 96 9.9 merc 4 stroke
Change the lower unit oil! add sea foam and take it for a ride. Top of your fuel tank. Don't over fill! You don't even have to put the boat in the water just shake it up. Tilt motor down so you have no water. Blow out your intakes for live wells. That's it. Oh check the plugs in the spring. If you have NGK spark plugs they should be good for many, many years. I have the same plugs in my Chevy Suburban since I bought it new in 2003. I think if one of your motors is a 2 stroke you do need to fog?