Lloyd's answer is very complete.
I would only add, since the topic comes up often on the CS group, is that
many boats claim "self bailing" but rarely deliver fully on that promise.
If a heavier engine is put on the transom ( often a 4 cycle instead of the
designed for 2 cycle) it can cause the stern to be heavier than the original
design. If one stores their batteries; gasoline tanks; baitwells, etc. near
the stern... often that weight will put a drain under water. If it rains a
lot, and the boat is left in a slip, lots of time leaves or other debris
will block the drain holes, and the boat will fill and can sink. If a
heavier than designed boater runs the boat, and he steps near the stern...
often the boat will be below the designed level.
In the case of a Carolina Skiff; a Boston Whaler; or other fully foamed
hulls, sinking isn't the normal result. However, they, too, can still allow
a lot of water to get in... if the stern gets too heavy.
Lloyd's comments about boats ( such as yours... apparently,) that have
bilges below their "self bailing " decks can go under if the "self-bailing"
doesn't work well. Water, sooner or later, can work its way below and sooner
or later the battery will run down after pumping that water out. This is
assuming that a boat is left for a long time moored or tied to a dock, and
lots of rainfall is present.
I installed "flapper" and "ball type" fittings on the drain openings on my
former boats, to allow water out, but not in. They didn't work perfectly,
since the seal is not compete. Water would leak in if I stood near the
stern. Not a lot of water, but enough to have to clear the decks with a run
forward, allowing the "self bailing" hulls to finally, self bail.
Certainly, most self-bailing hulls will clear their decks while you are
under way. Not quickly, but they will clear. If you took a heavy wave over
the bow, the long drain time can be disconcerting.
I hope all of this isn't too discouraging,...but I haven't found a perfect
"self bailing" hull yet. RG
--
RichG manager, Carolina Skiff Owners Group on MSN
http://groups.msn.com/CarolinaSkiffOwners
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