If you truly have a fuel leak, I'd be looking for the source. Also its mixed with water? If the cover isn't leaking, you might have the foam filled hull saturated with water. What year/type of boat is it?
It's a trailer queen. Sort if. I wouldn't bother putting bottom paint on if it's not left in for extended periods of time. I'm doing mine without bottom paint, if its an issue later I'll put it on. But I'm in freshwater.
Just recalled from back in the day.... In tech school me and a buddy rebuilt the transmission in his moms car, road tested just fine. Cleaning up drain pans, found a thrust washer Laying there. What to do..... She drove that car for another eight years without issue. Stuff happens.....lol
Just...
If the batteries are fully charged and disconnected when you put it to sleep, they should be fine in the spring. I disconnect the negatives to eliminate any parasitic draw. If the battery goes bad by spring, it didn't want to be a battery anymore anyway. As far as charging, leave them in place...
I suspected the race was missing from the earlier pics also. I just assumed he took it out before the pics were taken. If its loose enough to remove by hand, it needs a new hub.
Yes, battery test, new ignition, and clean all connections at the battery and Bloch, including the grounds. After you think the connections are clean , clean them again.
Low hours on an old boat, truck, or car, could lead to problems. Think letting a car sit for a year in the driveway, or more, it will have issues. Boats sit alot. A daily driver seems to run well,