FOR IMMEDIATE RELEASE
Press Contact: Scott Croft, 703-461-2864,
Date: January 9, 2007

REASONS WHY INBOARD/OUTBOARD POWERBOATS SINK

BoatU.S. Goes to the Insurance Claims Files for Answers


After publishing a recent study identifying the causes for accidental
outboard powerboat sinkings, Seaworthy, recreational boating's damage
avoidance magazine, has combed through the BoatU.S. insurance claims
files to identify the reasons why inboard/outboard (I/O) powerboats
sink. Interestingly, while outboard powerboats are similar in design to
I/O's -- and often made by the same manufacturer -- the study found
vastly different reasons why each accidentally sinks.

Outboard powerboats tend to sink at the dock due to poor cockpit
designs that trap water, but an I/O's weakest link is the delicate
connection between the inboard engine and the outdrive unit, called
bellows.

"The use of bellows or boots -- pleated, flexible rubber membranes --
that run between the inboard engine and partially submerged outdrive to
seal the transom where cables and shafts pass through have one
weakness: a limited lifespan," said Seaworthy Editor Bob Adriance. He
says that bellows should be inspected annually -- and more often in
hot, sunny climates. "Any bellows that is over five years old is living
on borrowed time," said Adriance.

He adds, "Many boats have more than one bellows (driveshaft, shift
cable, exhaust, etc.) any one of which has the potential to sink the
boat. And if one shows wear, they all should be replaced."

Here are the top reasons why I/O's sink:

At The Dock:
#1 (44%): Leaking bellows. A surprising number were attributed the
small shift cable bellows.
#2 (23%): Failed below waterline fittings, hose clamps, and melted
hoses as a result of overheating.
#3 (15%): Failed above waterline fittings. Heavy rains overwhelm
cockpit scuppers.
#4 (11%): Poor docking arrangements: Boats or outdrives that snag on
docks.
#5 (6%): Uninstalled drainplug.
#6 (1%): Miscellaneous such as a cracked engine block.

While Underway:
#1 (36%): Struck a submerged object such as rock or logs.
#2 (24%): Failed below waterline fittings.
#3 (20%): Leaking bellows.
#4 (12%): Swamping.
#5 (8%): Miscellaneous.

Gene Kearns wrote:
On 9 Jan 2007 12:48:19 -0800, Chuck Gould penned the following well
considered thoughts to the readers of rec.boats:

Outboard powerboats tend to sink at the dock due to poor cockpit
designs that trap water....


.... are we talking cut-away transom here or ?


I think they're talking about boats designed so that the scuppers can
become easily clogged. We've had 30" of rain around here in the last
few weeks. If a boat were left unattended out in the weather, and if
the scuppers got clogged with debris from a tree or similar
obstruction, it could sink pretty easily. It's not uncommon to see
dinghies tied alongside a dock that are completely swamped this time of
year. A lot of those swamped dinghies would also be reported as
"outboard power boats", but it's hard to imagine many people making an
insurance claim for a swamped dinghy.

Short Wave Sportfishing wrote:
On 9 Jan 2007 21:33:02 -0800, "Chuck Gould"
wrote:

Gene Kearns wrote:
On 9 Jan 2007 12:48:19 -0800, Chuck Gould penned the following well
considered thoughts to the readers of rec.boats:

Outboard powerboats tend to sink at the dock due to poor cockpit
designs that trap water....
.... are we talking cut-away transom here or ?
I think they're talking about boats designed so that the scuppers can
become easily clogged. We've had 30" of rain around here in the last
few weeks. If a boat were left unattended out in the weather, and if
the scuppers got clogged with debris from a tree or similar
obstruction, it could sink pretty easily. It's not uncommon to see
dinghies tied alongside a dock that are completely swamped this time of
year. A lot of those swamped dinghies would also be reported as
"outboard power boats", but it's hard to imagine many people making an
insurance claim for a swamped dinghy.

That's what I was wondering. The main focus of the article is the
vagaries of I/O design, but somehow outboards got lumped into it.

I don't think I've ever seen a outboard swamped at dockside after a
heavy rain, but I've seen a few I/Os full to the brim over the years
and not necessarily from rain either.

Although to give the article some credence, I did have my Ranger at
the old marina a couple of years ago after the Contender was pulled
for late season fishing. The Ranger has a cockpit drain system that
lies towards the stern in the corners and has a ball/float system
keeps water out and drains when there is excess water. After one rain
storm, there was excess water in the cockpit as one of the ball/floats
got stuck somehow, but other than a slight list, the boat didn't sink.

I can see Gene's point about open transoms with outboards. A couple
of the salvage boats I've looked at over the years had open transoms
which I imagine could accommodate swamping easier.

If the boat owner does not check up on his boat during the fall and
winter, it is not uncommon for leaves and pine straw to clog the
scuppers during the fall, and then the heavy winter rains to cause the
boats to fill up with water.

Chuck Gould wrote:

Gene Kearns wrote:

On 9 Jan 2007 12:48:19 -0800, Chuck Gould penned the following well
considered thoughts to the readers of rec.boats:


Outboard powerboats tend to sink at the dock due to poor cockpit
designs that trap water....


.... are we talking cut-away transom here or ?



I think they're talking about boats designed so that the scuppers can
become easily clogged. We've had 30" of rain around here in the last
few weeks. If a boat were left unattended out in the weather, and if
the scuppers got clogged with debris from a tree or similar
obstruction, it could sink pretty easily. It's not uncommon to see
dinghies tied alongside a dock that are completely swamped this time of
year. A lot of those swamped dinghies would also be reported as
"outboard power boats", but it's hard to imagine many people making an
insurance claim for a swamped dinghy.


I wish I would have saved the Boatus magazines that had all articals on
sinkings. They had run a series on why boats sink. Each month they
would spotlight a certin style/type of boat - ie io's, inboard and
outboards. And cruisers, open's sportfish, runnabouts. This artical
looks like part of one I saw, maybe the whole thing.

Capt Jack R..

Reginald P. Smithers III wrote:
If the boat owner does not check up on his boat during the fall and
winter, it is not uncommon for leaves and pine straw to clog the
scuppers during the fall, and then the heavy winter rains to cause the
boats to fill up with water.

Or they thought the bildge pump would take care of the flooding, that
is, until the battery went dead, and.....