I have a 1987 18 foot 2+3. I have owned it as the second owner since 1989. Every year I winterize it. I was taking care of my Mom at the time and in her later stages I could not leave the house to use the boat. I am concerned about the motor seizing up. What I did to winterize it was to using the spray can of fogging fluid while the engine was running at an idle and opened the secondaries, and slowly added fogging fluid until the motor stalled. I know you are supposed to put a teaspoon of oil in the cylinders and crank it but that is not what I did.
So anyhow I won't be using it this summer but want to know what I can do now in order to prevent the motor from seizing up. It has been over 5 years since it was run. I would like to spray a combination of WD40 and motor oil into the cylinders through the spark plug hole without having to crank (starter replacement due) but am wondering how best to do it. I know I don't want to overload the cylinders but just blow a fog in there. Any suggestions. I was also thinking of placing a torque wrench on the crankshaft pulley and give it a partial spin to guarantee it is still moving. Which direction is the way to move it, or doesn't it matter. No battery in the boat.
Background. I had a body shop for 20 years and also became a licensed state inspection mechanic. I appreciate your suggestions. Cars and boats are two entirely different ball games. This boat only has about 600 hours on the original motor. Thanks ahead of time. The photo is the original gel coat.