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Troubleshooting 101
- Water
"If water can find
a way to get in, it will." It isn't a proverb, but it should be. Ask anybody
with a boat. Chances are good, they'll have a story.
Most
of the time, water stays outside of a boat's hull. Most of the time. But
when it doesn't, a boater has to make some fast decisions, the most important
of which is, how fast is it coming in? Here is a fact you will never remember
if faced with the sudden appearance of water around your ankles while
boating: a two-inch hole that is one foot below the waterline results
in 78 gallons/minute entering the boat. Water weighs on average seven
pounds/gallon so with every minute the hole isn't plugged, you are adding
almost 500 pounds of weight to the boat. That ratio increase as the boat
sinks lower in the water.
A big
cause of trailer boats taking on water is found-or in this case-not found,
at the center of the transom. A missing drain plug that is used to close
off the cockpit drain when launching is responsible for 12% of trailer
boat sinkings (and this usually occurs at the ramp). Unfortunately, it's
a common theme in the "Off Ramp" stories that are found on page
36 of every BoatUS Trailering Magazine. Maybe more unfortunate
is the fact in each case, the boat didn't have to take on water at all.
Forgetting to put a drain plug in happens to all of us. Having a replacement
drain plug nearby doesn't happen enough. It is suggested every trailer
boater have a plug either attached to the wheel of the boat or in a place
where it can be quickly inserted in the event it is needed. Even at a
boat ramp, water will be looking for a way to get in. If you haven't unhooked
the boat from the trailer, it's probably best to try and pull everything
up the ramp and let the water drain while looking for the missing drain
plug (if too much water has gotten into the boat however, the tow capacity
of your vehicle may have been exceeded).
After
reviewing hundreds of claims a few years ago, BoatUS Insurance concluded
30% of boats sink away from the dock as a result of water coming over
the gunwales. This happens when the boat is out in seas for which it wasn't
designed (the freeboard is too low and the boat is being broadsided by
the waves). Trailer boats, however, get into trouble when waves come over
the transom, usually through the "cutout" where the outboard
engine is attached. BoatUS Insurance claims reveal 13 of 15 trailer
boats that sank away from the ramp, were hit by waves coming over the
stern. "Usually this doesn't happen with a single wave," says
BoatUS Technical Director Bob Adriance. " The first one will put
a lot of water in the boat but it's the second or third wave that will
swamp it." Once this happens, a bilge pump isn't going to be able
to offer much assistance because the waves will continue to roll across
the cutout as a result of the boat sitting even lower in the water.
One way to
get out of a situation like this is to put the engine in gear and slowly
move forward, allowing the water to actually drain through the
cockpit.
The problem, however, is with this much water in the boat, chances are
slim the engine is going to start. Of course the best thing to do is
never get
into this kind of situation. Turning on the VHF weather channel isn't
going to tell
you much when the bad weather is already happening.
If the
water has come from one heavy wave while underway or from a day or two
of rain while at a dock or on a trailer, the cockpit drain is usually
capable of getting it out. The key word here is "usually." Drains
get clogged. If you notice water is remaining in the cockpit, first check
the drain cover for obstructions (dirt, paper, hair, even seagull droppings
have been known to block water's exit). If this doesn't produce results,
then debris and the technical term called "gunk" is clogging
the hose or pipe. Take a look and see where the obstruction is located.
But take a look at one more thing as well: is the drain on the outside
of the hull sitting below the waterline? If so, then you've got trouble
(9% of boats sinking at the dock is the result of fittings that were supposed
to have been above the waterline but are pushed below by excess weight
(from water) according to statistics from BoatUS Insurance). This means
there is already a lot of water in the bilge, although most trailer boats
20 feet or less simply use cockpit drains rather than a bilge to handle
excess water.
One good
piece of news about trailer boat designs is the fact all boats under 20 feet
are required to have built in flotation in the hull.
While this won't
be of any help whatsoever in heavy seas or in heavy rain, it does
mean your boat isn't going to go to the bottom.
However,
in the event you find yourself in the worse situation of all, make every
attempt to make a "Mayday" call to the local coast guard, giving
location and the number of people with you. Make sure everyone
is wearing a personal flotation device and then make sure everyone stays
with the boat.
While
trailer boats usually don't have a bilge pump, there are numerous models
over 23 feet in length that are designed with a bilge to hold excess water
(and keep it fom covering the cockpit). If your boat has one, here's something
to understand about bilge pumps: they are rated on the basis of gallons
per hour that can be pumped (360gph, 500 gph, 800gph and up to 3700gph
are available through BoatUS). The ability to pump 360 gallons of water
per hour may seem like a pretty powerful pump but keep in mind this is
based on the pump and the hose and the water outlet all being at the same
level. Most, if not all bilges, are below the waterline which means a
pump may have to be powerful enough to move water as high as three-four
feet above where it is positioned. This means less than the rated capacity
of gallons per hour is pumped. And that means your bilge pump may not
be up to the job.
The
bilge is also home to gunk and debris that has settled after passing through
the cockpit. The screens need to be inspected, preferably before you launch
at the ramp. Some bilges are designed so the pump actually sits on a ledge
above the deepest area and, as a result, has less of a chance of getting
clogged than if it were at the very bottom. If your bilge isn't built
this way, give some thought to carrying a replacement screen (or two)
on your next trip to a BoatUS Marine Center.
While most
trailer boats don't have thru-hull fittings, statistics prove underwater
fittings are the cause of sinking in half the boats left in
a slip. These same fixtures were linked to 18% of the sinkings of boats
that were underway. Hoses attached to thru hulls or raw water cooling
systems or even outdrive boots can be the cause of a boat taking on
water. And when this occurs, the speed at which the problem is discovered-and
resolved-is crucial. This is why, on days when the boat is on the trailer
or in the water, spending five minutes to find potential places water
could enter the hull is time well spent.
BoatUS
Technical Director Bob Adriance says part of this inspection should include
taking a look at how these hoses are attached. This should be part of
the spring inspection but, more important, each hose should all be double
clamped to its fittings (especially the cockpit drains). Test the hose
itself and determine if there is any leak occurring (chances are good
the cockpit drain hose you have is the original).
Knowing where
to look if water gets into your boat is the most important step you can take.
Knowing what to do is the next. Thinking ahead,
however, before the water even gets in, is the best preventive
measure of all.
Seaworthy "Why
Boats Sink" http://www.boatus.com/seaworthy/sinking/ |