Seacocks? open or closed advice please

mickyp168

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Hi
Just watched an old episode of the TV series' Dragons Den'. It featured an entrepreneur who had the bright idea of an emergency bung for a failed seacock . It was a sort of long handled floppy plastic mushroom that when your seacock had failed at sea and you were sinking, you pushed it down the pipe and the water pressure sealed it by pressing against the mushroom flange from the outside. He was promoting that it would become part of standard safety equipment, as necessary as a life jacket. Well it was a few years ago and I have never seen or heard of it anywhere.
But it got me thinking. I just leave my seacock , which is in good condition, for the heads and sink open all the time. Should I be closing it when sailing or the boat is unattended? At sea, I am quite happy with 'bucket and chuck it' . Just wondering what is the best practice? I have never heard of anyone's seacocks failing.
Cheers Mick
 
just google seabung - you will see lots of them for sale

and yes close all sea cocks when you leave the boat for any length of time - if you dont and the worst was to happen there is no doubt your insurance co would not want to pay out on a claim
 
Hi
Just watched an old episode of the TV series' Dragons Den'. It featured an entrepreneur who had the bright idea of an emergency bung for a failed seacock . It was a sort of long handled floppy plastic mushroom that when your seacock had failed at sea and you were sinking, you pushed it down the pipe and the water pressure sealed it by pressing against the mushroom flange from the outside. He was promoting that it would become part of standard safety equipment, as necessary as a life jacket. Well it was a few years ago and I have never seen or heard of it anywhere.
But it got me thinking. I just leave my seacock , which is in good condition, for the heads and sink open all the time. Should I be closing it when sailing or the boat is unattended? At sea, I am quite happy with 'bucket and chuck it' . Just wondering what is the best practice? I have never heard of anyone's seacocks failing.
Cheers Mick

You can buy his invention and there have been several threads about it. The general feeling was that it would work well in certain circumstances but it is expensive bearing in mind the limited number of circumstances you could use it in. A better approach is to make sure that all your seacocks are made of the right material and are working properly.

What is not in doubt is that all seacocks below the waterline should definitely be closed when the boat is unattended for anything other than short periods. Cockpit drains shouls always be open of course. When sailing it depends upon heeling angles, position of through-hulls, use of anti-syphons etc etc. I don't close any seacocks when sailing but I don't heel!

If you don't close yours you might find they are gummed-up by shells in the open position. Don't force them if you are in the water. Take care to work them open in small movements if necessary.

Richard
 
just google seabung - you will see lots of them for sale

and yes close all sea cocks when you leave the boat for any length of time - if you dont and the worst was to happen there is no doubt your insurance co would not want to pay out on a claim

That's my practice too, although the evidence so far (about 35 years of sailing) is that no hose has ever failed. However there is a bigger risk (if you have others work on the engine for you, or move the boat) that the engine seacock, if shut, could damage the engine. Never quite sure of the right answer on that one, apart from our habit of leaving a big note on the cockpit table saying "OPEN SEACOCK BEFORE USING ENGINE".

We just have a set of wooden bungs but like the idea of these mushroom ones which I hadn't heard of before.
 
However there is a bigger risk (if you have others work on the engine for you, or move the boat) that the engine seacock, if shut, could damage the engine. Never quite sure of the right answer on that one, apart from our habit of leaving a big note on the cockpit table saying "OPEN SEACOCK BEFORE USING ENGINE".

Great minds Rupert. I'm aware that the marina might have to move the boat quickly in a fire situation or something so I put the ignition keys in an envelope on the table with ENGINE SEACOCKS CLOSED written on it. My only tiny concern is that the marina staff might just run around with any old Yanmar key and not even go into the saloon. However, engines take a while to overheat so if they don't move it far it should be OK and Speedseal Life seawater pump covers should preserve the impellers for long enough.

Richard
 
What is not in doubt is that all seacocks below the waterline should definitely be closed when the boat is unattended for anything other than short periods. Cockpit drains shouls always be open of course.

I've posted this before but it bears repeating. I once discussed this with my then insurers and was told that should the boat sink due to a seacock (even a cockpit drain one) being left open then I would not be covered. Equally I would not be covered for any damage or sinking due to rainwater inundation were the cockpit drain seacocks closed..
 
I would stick with wooden bungs that will work in all situations and dont degenerate over time. The lifespan of these plastic things is much shorter than the liklihood of an incident requiring their use, hence when you need them they will invariably be well out of date and disintigrating. Tie a wooden bung of appropriate size to each sea cock and know where your hammer is.

Closing the cocks is up to you and your insurance. I can see arguments both ways, that a seacock that is left alone is unlikely to suddenly fail but one that is opened and closed all the time might. Or that, if you don't open and close them regularly then you won't know if they are working should you need them. Of course, in any event they should be inspected at 'regular intervals', whatever that means.
 
I've posted this before but it bears repeating. I once discussed this with my then insurers and was told that should the boat sink due to a seacock (even a cockpit drain one) being left open then I would not be covered. Equally I would not be covered for any damage or sinking due to rainwater inundation were the cockpit drain seacocks closed..

It might be in your insurers interests to know a little bit more about boats. I know of at least one yacht which sank at its berth because the cockpit drain seacocks were blocked. Closed is just a more efficient way of blocking them.
 
I've posted this before but it bears repeating. I once discussed this with my then insurers and was told that should the boat sink due to a seacock (even a cockpit drain one) being left open then I would not be covered. Equally I would not be covered for any damage or sinking due to rainwater inundation were the cockpit drain seacocks closed..

Get a different insurer, one who understands boats.
 
I've posted this before but it bears repeating. I once discussed this with my then insurers and was told that should the boat sink due to a seacock (even a cockpit drain one) being left open then I would not be covered. Equally I would not be covered for any damage or sinking due to rainwater inundation were the cockpit drain seacocks closed..

They can't have it both ways. In the event of a rejected claim, the civil courts would throw that clause out as being unenforceable.

Richard
 
I don't see how a failed seacock would cause a vessel to flood, unless it snaps off due to corrosion ie poor maintenance. However a failed hose would flood a boat if the seacock is open. So as far as I'm concerbed bungs are a waste of time as if a hose fails you could close the seacock.
I do check hoses and hose clips occasionally and leave my seacocks open, working them occasionally to prevent seizing.
Modern boats have so many skin fittings each having a seacock most of which are difficult to access (due to bad sighting by builders) that closing before leaving the boat and opening when arriving is a right pain.
My last boat had the following seacocks :-
Cockpit drain 2
Engine intake 1
Generator intake 1
Engine exhaust (below wl) 1
Generator exhaust (on wl) 1
Aft heads 3
Forward heads 3
Galley 1
plus several on the topsides eg bilge pump outlets, shower tray pump outlets etc. which could cause flooding while sailing.
 
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Just wondering what is the best practice?

Lots of people religiously close all their seacocks whenever leaving the boat (or in severe cases of seacock-paranoia, even whenever the engine/toilet/sink is not being used at that moment) but have not yet provided a rationale for it that I find remotely convincing. I suspect it originates in the days of lead plumbing and gutta-percha where you really couldn't trust the internal pipework.

The cry is always "but what if the hose fails"? Well, why would it? It's made of reinforced PVC. Your hull is made of reinforced polyester. What if that suddenly develops a hole for no reason? Why is one a risk but not the other? Yes, if you have 60-year-old indiarubber hoses that are soft, sticky, and covered in white gunge then you have a problem - but the solution is to replace the perished hoses, not resign yourself to them failing and do your best to ensure that at least you'll be on board when the boat starts sinking.

Similarly, the idea of the hose "falling off the seacock" is also nonsense, as anyone knows who's tried to remove one deliberately. It's 50/50 whether heating, twisting, and the strength of a grown man will suffice, or whether you have to resort to a hacksaw. And that's even after removing the hose clamps. The internal pressure is basically nil, so again there's no reason for the hose to even be trying to jump off the seacock anyway.

Some people have badly-installed toilets that leak water into the boat if the seacocks are left open. That's temporarily a valid reason to keep them closed, but only until you can fit a high loop with an anti-siphon valve to eliminate the problem. Otherwise you're reliant on every crew, guest, and small child following your pedantic lavatory instructions to the letter to ensure you don't sink. Unless you only allow ex-submariners on board, that seems like an unacceptable risk to me.

In summary, my approach is to maintain the internal plumbing properly and leave seacocks open. "Maintenance" needn't be onerous, just satisfy yourself now and every few years down the line that the hose material is in good condition (not soft or sticky or obviously ancient or perished), that it's the correct size for the fittings it's on, that the ends are properly clamped and that it isn't chafing anywhere. You should be able to give it a good old yank without any niggling worries about something coming adrift. A couple of times a season, close and open each valve just to stop them seizing (you do still need to be able to close them to work on the plumbing, engine, etc). I also close mine before being lifted into the water from the yard, just in case I dismantled something over the winter and forgot to reassemble it.

There is nothing in my insurance policy requiring me to close the seacocks.

Pete
 
Lots of people religiously close all their seacocks whenever leaving the boat (or in severe cases of seacock-paranoia, even whenever the engine/toilet/sink is not being used at that moment) but have not yet provided a rationale for it that I find remotely convincing. I suspect it originates in the days of lead plumbing and gutta-percha where you really couldn't trust the internal pipework.

The cry is always "but what if the hose fails"? Well, why would it? It's made of reinforced PVC. ...

Well said, that man. The only seacocks I regularly use are the two sink ones, and that's only because the sinks fill if the boat heels a lot. The others - heads and engine - get opened at the start of a trip and closed at the end, and that's really only to keep them working which only really matters, of course, because I open them at the start of a trip and close them at the end ...
 
I think there are too many of these "your insurance won't cover you if you forget to do X,Y or Z". To take the example of domestic theft insurance and you forgot to lock your door, the insurance is still obliged to pay up for damage and loss. It is unreasonable to expect the insuree never to be forgetful. It would be different if a proper lock were not fitted and used normally. The same would apply to seacocks (although I too do not see how one could fail without some external cause.)
My own practice is to close all of them except cockpit drains on leaving my boat for an extended period and to exercise them regularly so you know they will work when needed. Incidentally, 2 boats I have owned had no cocks on the cockpit drains, this is bad practice as you have no way of isolation to facilitate changing hoses.
 
Incidentally, 2 boats I have owned had no cocks on the cockpit drains, this is bad practice as you have no way of isolation to facilitate changing hoses.

My boat has no seacocks on the cockpit drains, but they come out above - just above - water level. Fitting them would only be adding an additional potential point of failure. Didn't ball toilets, as originally fitted to Hanto Biru, have no seacock at all?
 
All my through hull seacocks are closed when leaving the boat, not too worried about sinking due to hose failure, but as my boat was on a drying mud berth I've found random critters i.e. crabs which have decided to have a look up the inside of the pipework and either end up in the strainer or causing issues with the bog. I've even found one wandering around the bilge before, which I think made it through the the sink drain! Little devils!

Plus obviously the mud then nicely plugs their escape route.
 
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