Cockpit drains

brianbaldwin

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Hi,
I'm fitting out a Colvic Victor 40 and am about to do the cockpit drains. The cockpit is very deep and protrudes into the aft cabin. I can't take the drain hosepipe to above waterline at the sides as it would get in the way of access to the cabin. The hoses could go go down below waterline and then up again to exit above waterline or straight down through seacocks through the hull. Any one know of any yachts with below waterline drains and problems with this arrangement?
 
G'day Brian, and welcome to the YBW forums with your fist posting.

Re Cockpit drains, are you sure you need them? I would think that with an aft cabin you would be getting a bit of spray or rain perhaps but not a lot of swamping.

Have you considered a small auto on/off pump?

I would row a mile rather than have extra holes below the water line, and it sounds like running any drain system that will drain above the water line is going be problem no matter how you rout it.

If you must have large drains, consider a flexible line between the cockpit drain and out to above the water line that can be clipped up out of the way when not sailing.

Andavagoodweekend......
 
No problem with the hoses going straight down to seacocks below the waterline. The Westerly Berwick I sail is like that and I imagine other similar Westerlies are the same. Make sure you use good sturdy reinforced hose and double clips on the seacocks even if not on the drain fittings. You will have to leave the seacocks open if you want to drain rainwater but exercise them regularly to prevent them seizing.
Going down and then back up again to above the waterline does not sound like a good idea. It will slow down the rate at which water will drain and there will be a greater potential for them to become blocked.
 
Hi Many thanks for the advice, I did trawl through the thread you linked to but it didn't really solve my dilemma - all boats are different I guess. The transom is above the DWL so could try to get hoses to there, but they would have to go "uphill" through a couple of dwarf bulkheads and a watertight aft bulkhead so not an elegant solution. I also need them to be quick draining as I beleive the RCD stipulates minimum times for draining cockpits and this boat is supposed to be Ocean capable, although I will probaby use it only in coastal waters.
 
Try very hard not to allow anything other than a steady downward slope to the hoses and they need to be crossed. I had large hoses fitted to my last boat; they were crossed as they are supposed to be, but they also were horizontal or slightly up hill as they crossed and sand etc tended to accumulate in the hoizontal part. I tried to clear it by pushing a running hose down the drains from time to time, but, I suspect, they were steadily becoming filled with sandstone!
 
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So they drain effectively on either tack

[/ QUOTE ] Sorry I do not understand how crossing them will help.
Neither my own boat nor the Berwick I have crewed for many years have them crossed. I suppose mine could have been crossed if I had put the skin fittings closer to the centreline but I have not found any reason why the should be. They are separated in the Berwick by a large chunk of Volvo Penta mechanical gubbins so crossing them would be impractical.
 
Hmmm lots of food for thought. I think I will have to go for underwater skin fitting given the layout of the aft cabin, although it wil give me some worries as I will have to leave one of the drain seacocks open to cope with rain water when on its mooring. Are ball valves suitable as seacocks when fitted to a brass skin fitting and should a non return valve be fitted as well? I am fitting two 1 1/2" cockpit drains. Thanks awfully for all your contributions here. /forums/images/graemlins/smile.gif
 
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I thought the idea of crossing the drain hoses was to prevent water coming back into the cockpit when healed rather than facilitating drainage

[/ QUOTE ] Now that I can understand but it is only relevant if the corner of the cockpit where the drain is situated goes below or at least close to the water level when heeled.
 
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wil give me some worries as I will have to leave one of the drain seacocks open to cope with rain water when on its mooring

[/ QUOTE ] Don't worry unduly about it. The aforementioned Berwick has not had any of its seacocks, with the exception of the engine cooling water inlet, shut in 30 years. Now of course they can't be shut and the owner realises that following the "good advice" he was given was a mistake.

If a seacock fails it wont make any difference whether it is shut or open and if you use good reinforced hose double clipped to the seacock then that is not going to fail either. It's as sturdy as the grp layup in some small boats. Ball valves are often used as a less expensive alternative to seacocks but do not use ordinary brass for anything below the water as it dezincifies. Dezincification resistant (DZR) brass is the absolute minimum you should be considering but the best, without doubt, is bronze. Stainless steel is not generally considered suitable below the waterlevel either. Beware of an alloy known as "Tonval" it was discussed on here at length a couple of years or so back after it featured in the near loss of a fishing vessel. You may be able to find what was said by searching but it can be an uphill struggle sometimes to find things with the inbult search function.

Non return valve are not normal except for the "joker" valve sometimes fitted in toilet outlets.

Try to keep this thread live until at least Monday as by then all those lucky enough to be out sailing this wekend will be back at their desks, bored out of their minds and only too anxious to give you loads of advice.
 
Thanks Vic S,
Can it be assumed that Marine Chandlers only sell DZR brass skin fitttings and are they marked as such? I inherited two unfitted brass skin fittings with the boat so how do I tell? FInally, how have ball valves failed in the past (rather than the skin fitting they were attached to) as they seem pretty sturdy to me.

PS Wish I was out sailing rather than building!
 
Has anyone tried timing how long there cockpit drains take to empty a full cockpit of water?.
Our yachts previous owners did and it took over an hour, they fitted two 4 inch plastic pipes straight through the transum.

Brian
 
If it helps, Avocet has two drains in the bottom of the cockpit and it's not far above the water line. They go straight through the bottom of the boat via a couple of Blakes seacocks and we've had no trouble. (never had green water in the cockpit though)!

If you don't like the idea of cockpit drains going through the bottom of the boat (and I can understand this!) how about letting them go to a holding tank somewhere convenient and then having a bilge pump to empty the holding tank? Not ideal if you DID get swamped but I've an idea that Avocet's twin bath plugholes wouldn't actually help much either! IF you want effective fast self draining, you really need a couple of HUGE holes!
 
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Can it be assumed that Marine Chandlers only sell DZR brass skin fitttings and are they marked as such? I inherited two unfitted brass skin fittings with the boat so how do I tell

[/ QUOTE ] No you cannot assume anything. You must always check. I don't know if they are marked. Probably just with the makers part number. The only way you will be able to tell for sure if anything is unmarked is by chemical analysis but that will cost more than the items are worth. There are some portable spark spectrometers about. You might find one at a scrap merchants and be able to persuade them to test your fittings for a reasonable sum but you would have to be certain that the instrument could give you the information you require and that the operator really did know how to use it. Dodgy that!
 
I think the previous owners got swamped in mid Atlantic on there way to the States, as the pipes are marked made in USA. I would concider 2 x 4 inch pipes as HUGE enough, this winter plan to fit rubber flaps to stop following seas joining the crew.

Brian
 
Hi

I was swampt this by a ferry off dunkirk in july the wave broke over the side of the boat filling the cockpit, I thought we were done for. The washboards were in so very little water entered the cabin. But the cockpit was full, we were sitting up to our waists in water. It drained through the transom very quickly, say 15 secs, but then the "hole" under the seat is around 12 x 18".

The "bath plug fittings" I have seen on westerlys and victors would have taken hours to shift it. I have sailed a few victor 40's and the wave that did for me would have broken over the deck saloon of the victor, filling its cockpit with a ton or more of water. Not a good thing but we are asured that yachts are supposed to remain stable in these conditions - I for one wouldnt like to test the theory.

I can understand 4" cockpit drains! The bigger the better as far as my experience is concerned.

My mirage (previous boat) had bath plug drains in a centre cockpit that went straight down into skin fittings in the bilge. Because they went into the "engine room" the insurers insisted that they were metal at least up to the water line.

Hope this lot helps a bit.
 
Hope this is not too late

but I replaced the ball valves on my cockpit drains with Blakes seacocks; the ball valves became very stiff to operate after a few years and I suspect that the (?nylon?) seatings had swollen slightly. No such trouble with the Blakes seacocks of course.

I close the seacocks on the mooring and fit a cockpit cover.

Drains are crossed and the hoses are reasonably straight. I made a couple of "wooden mushrooms" to stop debris getting into the pipes during refits.
 
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