Galley sink drain question

[Boo2]

Hi,

Sunrunner currently has the galley sink drain plumbed to a T-piece in a cockpit drian (see pic beloe) but my survey report said that this is not very good because a fault in the gally sink drain pump or the long hose from its outlet could sink the boat. It recommended plumbing the drain to a "skin fitting high in the topsides" but this will mean leaving dirty streaks down the side of the boat. I wondered whether it would be OK to plumb to a skin fitting and seacock just above the waterline instead ?

All opinions welcome,

Boo2

 

[pvb]

... my survey report said that this is not very good because a fault in the gally sink drain pump or the long hose from its outlet could sink the boat.

Essentially, a fault in any seacock hose - long or short - could sink the boat. However, it's worth remembering that there's virtually no pressure on any of these hoses. If the hose is in good condition and properly secured, what's the real risk??

 

[Poignard]

My galley sink drain is plumbed, via a hand-pump, to a seacock below the water line. It works perfectly well and is no more unsafe than anything else connected to a seacock. The seacock is, of course, shut when the boat is left unattended for any length of time.

 

[prv]

Is the top of the sink below (or very near) the waterline? If it is, then the one-way valves in the pump are the only thing holding the sea out and I understand the surveyor's concern.

Otherwise, I'm not convinced it's that much of a problem, though of course minimising the number of holes and hoses below the waterline is always desirable.

Pete

 

[Rivers & creeks]

The Kipper has the sink plumbed to a drain 2 inches above the water line, no foody streaks. We put an inline ball valve so that should we ever heel far over (ha ha Colvic Watson 34, more stable than a cat!) we can shut it off.

 

[johnalison]

The only question seems to be whether your hose from sink to fitting is accessible for inspection or repair. If part of it is not accessible, the surveyor must be correct, but otherwise I can see no risk worse than mine which is the same as parsifal above, and one skin-fitting fewer.

 

[PetiteFleur]

My Moody 33 is exactly the same and although there is a ballvalve on the skin fitting, it never gets turned off as I would have to empty the cockpit locker & dismantle the locker floor to get at the seacock everytime. I'm happy with the arrangement as I've personally inspected and renewed any suspect bits.

 

[GrahamM376]

Our galley sink has its own gravity drain via a seacock, discharging just above the boot line, as do both heads washbasins. Never had a problem but do shut the seacocks when leaving boat unattended for long periods but wouldn't want to shut cockpit drains so, I prefer separate drains.

 

[pathfinderstu]

if your worried about stains down the hull why not cut a lip for the hull discharge hole and glue it there, you could use an old squeezy fairy liquid bottle etc for the material, easily replaceable if knocked and would sqash flat.

 

[theoldsalt]

Boo2,

In my experience once a surveyor has put a comment into a survey report, however advisery, unnecessary, illogical, stupid etc, then the insurance companies pick up on it and insist that the is "fault" is rectified/changed. This seems to be particularly favoured by the "cheap" companies. It seems only the larger, more reputable companies that are willing to see sense.

In this particular case my sink outflow goes to a skin fitting at boot-topping level, ie about 2inches above the waterline - of course via a sea cock. My boot-topping is hard antifouling and therefore easily wiped clean.

 

[mawm]

Boo2 - My sink is plumbed exactly the same way as you describe and it was responsible for my boat getting swamped. A couple of gull feathers and a cake of their p** on top blocked the outlet at the seacock, a week of very heavy rains allowed the water to flow into the sink and then into the boat to at least a foot above the sole. That's a lot of water! If it had been any more I think that there would have been a back flow up the cockpit drain and……….

 

[mitiempo]

I think the sink drain should have its own outlet - good example of why above.

If you cook while underway the best place is well under the waterline so it will drain on both tacks if it is a sailboat. For powerboats and cats the boot top works well.

Seacock or ball valve in each case of course.

 

[Talulah]

Our sink drain outlet is about 150mm below the water line.
I would be more concerned by your green 'bilge' hose between the skin fitting and 'T' piece. I have found once old that type breaks really easily.

 

[Gordonmc]

For the sake of peace and quiet don't put your skin fitting just above the waterline.
That's where my sink drains come out and the racket of water gurgling in and out of the hole with every ripple is a real irritation.
Closing the cocks makes little difference.

 

[Strathglass]

My sink drain exits a few inches above the static waterline but there is a non return valve and a seacock in the pipe. Quite small diameter pipes are used. We sometimes have to use a rubber hand pump thing to clear it when it becomes blocked but that is not a real problem or a safety hazard.

The cockpit drains are a different and more important matter.

Two 2" diameter crossed short pipes. The cockpit empties very quickly - even from full. (had that happen in the North Sea)

I would never compromise the cockpit drains by adding additional potential problems.

Iain

 

[NormanS]

if your worried about stains down the hull why not cut a lip for the hull discharge hole and glue it there, you could use an old squeezy fairy liquid bottle etc for the material, easily replaceable if knocked and would sqash flat.

That's what I do. I make short "Gargoyles" simply by using duck tape in the skin fitting.