kbkindle this is the first year that i used seafom additive rather than ring free in my yamaha hpdi engine. some say not to add stabolizer and seafoam that seafom in enough what say you kb does not say in any books but seafom says stabolizer not needed i dont know

I've heard of plenty of guys just using the seafoam as a stabilizer and it's worked out good for them.

Have no idea, as I have never had to winterize my boats. Even when I lived in Colorado I would still use my boat every weekend. Just had to drive further