What Sinks Sailboats (wood excluded)– Survey

[GordMay]

Bob:
You cannot mix intake (engine) & discharge lines. You could connect the various drains (sink, & bilge pump) to the cockpit drains, as described. The head discharge would probably be a pretty long run, though.
An electrician’s “fish tape” (or part thereof) is a handy multi-function tool aboard, which could also clean out clogged cockpit drains (straight to gently curved). The fish tape isn't much use in harvesting fruit, though ...

[bobola]

Gordy,

Think of 2 pipes, one on either side of the cockpit (port and starboard) going straight down, which puts them on either side of the keel. This keeps the intake from drawing in from the outake.

I drew just one side for the sake of simplicity...

As most cockpit drains are probably undersized anyway, this arrangement solves that issue.

As tenknots said, a failed bilge pump is just a symptom. A boat should not take on water. This includes wood boats, Most do to some degree, but as an example, my double ender, built in 1940, has only a manual bilge pump. (a large one, and 2 back-ups, but manual never the less). I usually pump the manual after each sail, about 4 gallons for a day of beating upwind. I take on no measurable water at dock. The true cause of sinking vessels, wood or not, is negligence. Not installing anti-siphons, not checking or maintaining hoses and seacocks, etc. A regularly sailed wooden boat is no more likely to sink than any other boat.
Now, before this becomes a true rant about wooden boats, I said my piece, and I'm done.

[delmarrey]

I see some major defects with the system you've discribed/drawn.

First, that's fine if your sitting in port but what happens when your transom rises up over the crest of a wave and slams back down or like on many vessels with positive bouyancy aft ends. Or, where the transom may over hang as much as 3 ft., like mine. http://cruisersforum.com/photopost/d...0TRIX1-med.JPG

Second, it's not really a good design to have the cockpit drains below the waterline, as you can see by some of the first posts on this survey.

I agree with the manifold design for intakes but prefer overboard discharge above the waterline providing the sinks and such are high enough for drainage. There's less back pressure and less chance of another source of sinking.

As for the Groco setup, the problem I see there is it has a large thruhull, then it reduces it down before the manifold (top of the elbow). What good does that do to have a large thruhull?
The manifold should be as large as the thruhull and then the outlets reduced.

So far, the lack of maintenance and good common sence seems to be the main source of sinking vessels.

[Sunspot Baby]

I have a plaque on the boat. It says:

Keep the water our of the boat
Keep the boat off the ground
Everything else can be worked out.

Simple but not always easy.

Sunspot Baby

Sunspot, I stand by my signature.

[bobola]

I see some major defects with the system you've discribed/drawn.

First, that's fine if your sitting in port but what happens when your transom rises up over the crest of a wave and slams back down or like on many vessels with positive bouyancy aft ends. Or, where the transom may over hang as much as 3 ft., like mine. http://cruisersforum.com/photopost/...20TRIX1-med.JPG

(you are correct – this idea would only work with a center cockpit, where the cockpit through hulls are in the center of the boat, down deep. Another option is to feed the aft cockpit drains via flex hose toward the deep bilge, into 2 manifilds and plug the existing holes aft. This is way more work than anyone would want to do but I still like the 2 hole idea. )

Second, it's not really a good design to have the cockpit drains below the waterline, as you can see by some of the first posts on this survey.

(I probably drew it wrong. I agree that the cockpit drains need to be above the waterline, or at least should be there)

I agree with the manifold design for intakes but prefer overboard discharge above the waterline providing the sinks and such are high enough for drainage. There's less back pressure and less chance of another source of sinking.

(agreed. Another setup I like is sink drains feeding into the deep bilge to a container and the water then fed overboard by a bilge pump. Hair and slime build up which means it needs lots of maintenance, but it lessens the chance if water incursion)

As for the Groco setup, the problem I see there is it has a large thruhull, then it reduces it down before the manifold (top of the elbow). What good does that do to have a large thruhull? The manifold should be as large as the thruhull and then the outlets reduced.

(agreed. If the engine is drawing off the manifold there can be no restrictions for the water it needs and the pipe feeding the manifold would need to be quite large)

So far, the lack of maintenance and good common sence seems to be the main source of sinking vessels.

(agreed. I recall a Morgan 41’ owner saying that there were 19 holes in the hull below the waterline. Nineteen is a big number! i first heard of the 2 hole idea in an email from a lake Michigan sailor. He went so far as to say that he lowers the depth sounder down one of the cockpit drain fittings, on a stainless rod, and plugs the cable into a cockpit electrical fitting. He has 2 large pipes feeding 2 large manifolds, and no other holes. nada!! When he leaves the boat he religiously turns the through hull valves off thereby guaranteeing the boat can’t sink…well…..nearly impossible to sink…. By his method he also guarantees that the vales get regular exercise. All too often you hear about someone doing through hull valve maintenance and they say that the valve is frozen. A frozen valve is a scary thing! I would rather have 2 holes than 19 any day, but getting there with a factory boat would take a lot of time and $$$.)

[captqrunch]

Ballast keels sink boats. :-)

Nahhh, I still maintain that owners sink boats

[CaptainK]

Quite simple.

Human error!!

Like the computer guys used to say GIGO
After all boats are perfect machines! Right?

[CaptainK]

[messingabout]

I once saw 18 foot skiff get chopped in half on Sydney Harbour. It was being raced by some hothead who expected a 45 foot solid wooden mono to give up right of way and turn on a dime.

[messingabout]

Q: What's the one thing all sunken sail boats have in common?
It's the main cause of sinking.

A: They're all monohuls with a heavy weight hanging underneath just biding its' time.

Cheap shot I know but I couldn't help it.

[delmarrey]

I've seen more power boats half under water then sailboats.