Cockpit drains-mismatched hoses to below waterline seacocks

Ross · Dec 15, 2009

Change the cockpit drains to 1 1/2 inch .

Stu Jackson · Dec 15, 2009

Whatever you do, don't use 5200 for anything but a hull to deck joint and maybe for your keel to hull joint.

OD sounds very strange for boat hose. Hose is measured in ID.

While WM may not have hose couplers, try a plumbing store, or ACE Hardware.

And what do the "dreaded Forespar valve handle" issues have to do with the cockpit drains?

Bud22569 · Dec 15, 2009

ccarmody said:
We are new owners of a O'Day 37 and have come across the dreaded Forespar Marelon/RC Marine seacock/valve handle breakage. I have replaced the valve, but the previous owner used 1-3/4 hose from the cockpit drains to the 1-1/2 tailpipes on the valves. Since the valves are below the waterline and need to remain open all the time for rain, I'd really rather use the proper hose size on the tailpipe - 1-1/2" - the problem is joining that w/ the 1-3/4" OD of the cockpit drains. At first I thought I'd build some sort of coupler between the two hose sizes, but west marine and others seem to stop at 1-1/2" fittings (or go to 2", 3"+)

The next thought is to bond a 1-1/2" marelon tailpipe via 3M 5200 to the bottom of the cockpit drain and then have one contiguous 1-1/2" piece of hose between the two. The OD of the tailpipe threaded section and the cockpit drain are about the same- some 5200 followed by covering in fiber glassing should be ok? Ok w/ the different material types? Thoughts?

Thanks!
Chris & Jess
1979 O'Day 37 CC

I understand your plan and think it is a good plan. The new drains will be permanent, but I think that is what you are after. I think hose adapters would be a weaker plan than the plan you have presented.

Ross · Dec 15, 2009

What you need is "Fernco" rubber couplings. Go to any plumbing supply and tell them what your need is and they can supply you with the correct fiitings.

Roger Long · Dec 16, 2009

The only proper response I can see here is through hulls and seacocks that match the cockpit drain hose size. It's a quick job, less than an afternoon with a helper. Bigger is always better with cockpit drains.

The neck of a through hull that size is going to be pretty long. You might find that the top is actually above the waterline when installed. In that case, if you use bronze, you might consider not installing seacocks. Since you have to leave them open, you aren't getting much safety benefit from them and there is no standing water pressure on the hose. After all, most sailboats are floating on a piece of rubber hose that connects the stuffing box to the shaft log and that has to take constant vibration and twisting from the shaft. No seacock there. Use the heavier hose intended for the same purpose. It will be stiff enough that you may have to insert the seacock in the hose as you insert it through the hull and take up on the nut.

If the seacocks are too low, you may still be able to get the top of the bronze above the waterline by using through hulls with full thread necks, a coupling, and a hose tailpiece.

If the drains are in an area where heavy stored items could fall against them or they could become hand or foot holds while trying to do something like fix an engine, then they should have seacocks.

Maine Sail · Dec 16, 2009

Roger Long said:
The only proper response I can see here is through hulls and seacocks that match the cockpit drain hose size. It's a quick job, less than an afternoon with a helper. Bigger is always better with cockpit drains.

Agree 100%!

Roger Long said:
In that case, if you use bronze, you might consider not installing seacocks. Since you have to leave them open, you aren't getting much safety benefit from them and there is no standing water pressure on the hose. After all, most sailboats are floating on a piece of rubber hose that connects the stuffing box to the shaft log and that has to take constant vibration and twisting from the shaft. No seacock there.

I do not believe you can buy long lengths of real stuffing box hose. It usually comes in short 6" lengths and would be quite expensive to buy six feet of it? Perhaps a call to Buck Algonquin may answer this..?

Also to satisfy the OP's insurance company, which will usually default to the surveyors suggestion, which is usually in-line with ABYC, you need a seacock.

ABYC H-27
"27.5.1 All piping, tubing, or hose lines penetrating the hull below the maximum heeled waterline, shall be equipped with a seacock to stop the admission of water in the event of failure of pipes, tubing, or hose."

Stuffing box hose vs. wet exhaust..

BTW Groco makes both a straight and sweep elbow 1 1/2" NPT to 1 3/4" hose, pipe to hose adapters. Personally I would not re-use Marelon in this application where the valve will not get regular exercise.. You do not need to Mickey Mouse this as the adapters are available..

Please also keep in mind that a full flow designed scupper system for 1 1/2" ID will NEVER use 1 1/2" ID hose. By design it can not. If you want to maintain an 1 1/2" ID for full flow you must use a larger hose. An 1 1/2" OD hose barb does NOT have an 1 1/2" ID and would not maintain the designed flow rate of 1 1/2".. Using an 1 1/2" ID hose on an 1 1/2" seacock will yield a restricted flow of roughly 1 1/4" to 1 3/8" due to the cross sectional thickness of the hose barb.

Your scuppers are likely an 1 1/2" ID thus 1 3/4" OD. The seacock pipe to hose adapter should be the same. Hope this helps..

Roger Long · Dec 16, 2009

Maine Sail said:
Also to satisfy the OP's insurance company,

Good point. I don't plan to ever sell my boat and my insurance is already as high as I can get it so I don't think about the hassle that can come up after a survey.

I would certainly put in seacocks if you can but, ABYC and insurance aside, if it is a choice between a nice straight, short run that you can run a stick through for clearing (as was the case on my boat) and a curving run of hose just to get to a through hull location where a seacock can be installed, I would go with the former as long as the bronze ends well above the normal resting waterline.

The ABYC maximum heeled waterline requirement covers just about every hole in a boat below the rail and I think it's pretty commonly ignored for through hulls above the resting waterline. It shouldn't be but a through hull that you can stop leaking just by tacking is a bit less critical than one that will always be immersed.

Stu Jackson · Dec 16, 2009

Any hose that HAS to mate with a fitting will eventually HAVE to be removed.

Using a glue makes NO SENSE, ever. Use a sealant and double hose clamps.

Please, for your own sake.