by Alan » Mon Jun 06, 2011 11:09 pm
Looks like the outside of a Depersia self-bailer, original equipment on the DSII. It's made of aluminum, and on the inside of the hull and visible on the cockpit floor, there's a brass hex plug with a rubber gasket that screws into the casting. That's how it is on my 1980 DSII, anyway.
There's a modern substitute, made of plastic, available from D&R Marine. I have one in my box of shiny stuff, and it does contain a floaty ball. My original one doesn't, but I suspect it might have at one time.
My understanding of the ball's function is that you can leave the self-bailer open, and the ball will float up and block water from coming into the cockpit. Then, when you're moving forward and creating the necessary venturi effect, the suction pulls the ball downward to open the self-bailer and any water in the cockpit is sucked out of the boat.
I've seen this work in practice in a 40-horse Boston Whaler, so I know it works if you've got fast-enough enough forward motion.
I may steal the ball out of the new self-bailer and install it in the old one.
The original Depersia self-bailer has about the same shape as the new one - a bit too flat to conform with the curves of the hull. Someone - my best guess would be the factory, since the PO's favorite solution to problems of this type was to slap car Bondo on the outside - created a fit of sorts with gray goop that looks like chewing gum from under a movie-theater seat circa 1965.
Having given it a lot of thought, I'll probably remove the aluminum self-bailer, clean it up, and reinstall it with some new marine-grade sealer. If I hit an obstruction (not that I would ever do that, of course) it would be a lot better to have aluminum take the hit than plastic.