Blanking off a through-hull

[AndrewB]

As a result of re-arranging my galley, there is now one through-hull that has no function. I don't want to weld it over, as I might use it again later.

What is the best way of blanking it off for the time being, before we relauch? The seacock is still on at present, but I don't want to rely on that alone -- after all it might accidentally get opened.

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[snowleopard]

option 1: whack a softwood plug up it from outside with a good coat of mastic then saw off flush.

option 2: if it's a ball valve, i.e the through-hull itself is threaded, you could get a blanking cap from a plumbers' merchant, screw on in place of the valve with ptfe tape.

option 3: if it's a blakes or similar, remove the seacock leaving the outside plate & bolts, cut a blank disc of scrap grp, drill to match the hole pattern and bolt down onto a bed of mastic.

as long as you avoid any solution with dissimilar metals you'll be ok.

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[vyv_cox]

Add a foot operated seawater pump to your galley. Extremely useful device and one that I shall have when I've worked out how to do it without removing space from this very crowded area on my boat.

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[upstream]

Excuss my ignorance, but why would you want a sea water pump in the galley?

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[snowleopard]

lots of uses for sea water in a galley to save use of fresh water:

first rinse before washing up

add 50% to water for cooking veg or rice

rinsing veg while cooking

making coffee for uninvited guests ;-)

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[AndrewB]

To be honest ...

... it was just that, a sea-water inlet cock. While I agree with all you say in theory, in practice I found I didn't use it enough. Not around European shores, anyway. Yet it had to be kept serviced.

As I'm revamping the galley, I've simply done away with the tap, so the seacock is redundant. Some day I might fit a watermaker, so I want to leave the through-hull there for the time being.

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[duncan]

Re: don\'t forget...

...the emergency live bait storage.....

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[vyv_cox]

I can't really improve on snowleopard's suggestions. If you have ever entertained a party of six for a spaghetti Bolognese or a highly coloured curry you would greatly appreciate the benefits of washing most of the remains down the sink without using precious fresh water. On any lengthy offshore cruise it will save a great deal of water if rinsing and preliminary utensil cleaning is done in seawater, just the final rinse in fresh. Vegetable washing and peeling are also OK in seawater.

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[Sinbad1]

Andrew

leave in place. Attach a length of appropriate sized pipe/tubing and to the end of the tubing attach another open/ close valve. Locate this above waterline if possible.

Your throughhull then has two valves to close and even if in the unlikely circumstances of both being accidentally opened, the end being above the waterline would prevent water ingress.

Whole system is then ready for use when needed.

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[30boat]

If it it's a ballvalve you can just remove the handle.Come to think of it you can do it with most types of seacocks.However, don't forget that seacocks need to be opened and shut regularly or they will seize.

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[poggy]

Hi,

Why not blank of the seacock at the outlet, then you will not need to risk a blanking plate on the hull and if it is opened by mistake it won't let in any water. It will also allow you to open/shut the seacock to keep it working for the future.

I would think it is best to avoid making any through hull changes unless absolutely necessary as it can create problems.

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[Guest]

Soft thick rubber pad + two wahsers and bolt

A thick rubber pad, cut to diameter of hole, two large flat metal plates and bolt + nut.

Drill centre of pad, fit bolt through with metal plates either side of pad. wind on nut and then fit into hole ..... wind up the nut onto the plate and squeeze pad out to be very tight fit in the 'ole ..... sealing it up. Make sure the bolt is not too proud and basically cut flush to the nut ..... I would leave the seacock in place and 'lash' the valve handle closed .... I would NEVER remove the handle completely.......



<hr width=100% size=1>Nigel ...
Bilge Keelers get up further ! I only came - cos they said there was FREE Guinness !

 

[AndrewB]

Thanks guys ...

I was hoping someone might know of a blanking cap for the through-hull, but it looks like they don't exist.

Of the many good suggestions, I will go with Sinbad1's, except I'll just cork and jubilee clip the end of the tubing above the waterline.

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