I have a 1992 Vovo ib-ob. It has the two cooling system where it picks up the lake water and the closed water system. Well today i started my boat up for the first time from winterization.It was over heating. Starting cheaking things and found out the resivor that holds the antifreeze was empty.I filled it up and the heating up problem was gone.But where could have the antifreeze gone. After i filled it up and ran it for awhile i recheaked it and it was still full.The only thing i can figure out is maybe the guy who winterize it drained it for some reason.any ideas will help