Foot operated galley seawaterpump: Which seacock

[vw1961]

On my Beneteau Oceanis 361 i have just pressurized water but I want to fit a foot operated pump for sea-water rinsing the dishes.

Under the sink there is just one valve for the drain, so I need to get the water from somewhere else.
I first thought about a T connection to the cooling water">engine cooling water intake but I am afraid to suck air into the engine so I won't do that.

Then I remembered that there is a second seacock close to the engine, it is connected to the drive shaft seal and to the aircondition. Could I attach it there? Whats the purpose of the Waterhose connected to the drive shaft seal?

Pictures attached. Yes there is corrosion on the sea cock, I will have it changed this winter



Thank you very much for your opinion, Markus

[JPA Cate]

Markus,

Maybe you could install a "T" fitting into the sink drain one, and run the pump off one side of the "T", and keep the other for the drain? Do it when you're hauled out, although it "could" be done in the water, using a "plumber's friend" over the outside of the inlet, to keep the water out.

Ann

PS. The run from the sink drain should be short, and easier to access and keep your eye on.

[bobnlesley]

Whilst we had probably similar concerns to yourself, we tee'd ours into the engine inlet 'just to see if it worked' about three years/300 hundred hours ago; it's still working fine. Engine's a Yanmar 3GM30F

[Suijin]

FYI the hose to the shaft seal is to ensure that it remains wet/lubricated. Some seal designs only require a vent/burp hose while others require a water supply. Adding a T to that would probably be fine, at leasts functionally for the seal, as it's not a pressurized system.

As for sharing it with the AC, I can't comment on the wisdom of that.

I would NOT plumb it to the engine intake but that's just me.

[Sailmonkey]

Originally Posted by JPA Cate

Markus,

Maybe you could install a "T" fitting into the sink drain one, and run the pump off one side of the "T", and keep the other for the drain? Do it when you're hauled out, although it "could" be done in the water, using a "plumber's friend" over the outside of the inlet, to keep the water out.

Ann

PS. The run from the sink drain should be short, and easier to access and keep your eye on.

YUCK!!

If you tap into the sink drain that your rinsing the dishes into, you’ll recirculate the stuff you’ve just rinsed off of the dishes!

I’d go with the other fitting. The A/C isn’t going to pull water back through the foot pump, and the stern tube just doesn’t care.

[nautitrix]

Originally Posted by bobnlesley

Whilst we had probably similar concerns to yourself, we tee'd ours into the engine inlet 'just to see if it worked' about three years/300 hundred hours ago; it's still working fine. Engine's a Yanmar 3GM30F

I too am questioning whether or not to "T" into heat exchanger intake for the same purpose. Are you using a foot pump or a saltwater-washdown type pump? I was wondering if the raw water pump would intake air but I thought the valving of the pump would stop this. I Also have a3gm30f so you have solved my quandary thank you. Three years and three-hundred hours is a good enough experiment for me.
BobV

[jamhass]

Ours is plumbed into the engine raw water line after the strainer. There is a good quality check valve in the line to ensure no air getting into the raw water for the engine. Our foot pump is a Whale, and the internal valves are quite reliable. Never had any issues re air in the raw water.

[JPA Cate]

Originally Posted by Sailmonkey

YUCK!!

If you tap into the sink drain that your rinsing the dishes into, you’ll recirculate the stuff you’ve just rinsed off of the dishes!

I’d go with the other fitting. The A/C isn’t going to pull water back through the foot pump, and the stern tube just doesn’t care.

You're right, it would not be bacteria free. It would not, in any case, most, if not all, seawater contains bacteria. Plus, it is always immersed, and its purpose is to rinse dirty dishes, pre-wash.

If you take the sea water off the engine intake, you have to not use it, or at least use it very carefully, when the engine's running, in order to not deprive the engine of cooling water. This would probably only be a concern with a voyaging boat; one could plan to do dishes not underway.

Ann

[deblen]

When you tee into a thru hull/seacock,you are setting up for a possible problem(s) later.

If both lines to the seacock tee are suction (exe. engine & sink faucet),a leaky faucet,etc could cause the engine to suck air,etc into the cooling water.

If one line is a drain & the other is suction (exe. sink drain & water intake,you may suck the sink drain trap contents into the water intake.If there is no trap,you will only suck air down the sink drain.

Yes-many have tee'd several items into a common seacock,& sometimes it works ok.
Before you try it,draw a diagram & think it thru.Ask yourself all the what ifs.

Personally,I believe teeing at seacocks is dangerous & more risk than installing another proper seacock,but that's me.

Len

Note: the corroded thru hull/skin fitting in your pic is not a proper seacock & I question the metals used in all of it's outlets. Also,I question the black hose.It looks like "auto heater hose" & not proper below the waterline marine hose. Suggest you read Maine Sail's Seacock article" & check closely @ your next haul out.
Hope this helps.
http://www.pbase.com/mainecruising/replacing_thruhulls

[TrentePieds]

This can't be so urgent that it can't wait till next time you haul. Then just add a dedicated seacock. In a frozen snot hull they aren't hard to install when you are on the hard. If it's worth doing at all, it's worth doing right :-)!

In a boat as beamy as yours, you'll want to keep the new seacock near the centreline. While you are at it, you might as well make it big enuff for a deckwash/anchorwash pump while you are at it, even if you aren't installing that pump at the same time.

TP

[vw1961]

I always thought it is safest to have as few through-hulls as possible, but i start to change my mind: It is probably far safer to have a through hull under the sink with the pump and the faucet directly attached to it, than to T- into an existing through hull in the engine compartment and run 5-6 meters of hose through the boat in inaccessible places.
The through hull under the sink, at least at my boat, is also much mor convenient to open close when leaving rhe boat than the engine seawater inlet for which i have to lift the metress and wooden board in the aft cabin.

@nautitrix: i think whether to "T" into the engine intake is not so much a question about which engine you have but more depends which kind of water pump for the dishes

[TrentePieds]

VW: I think you are on the right track. As I see it, there are two criteria that must be satisfied simultaneously: 1:There should be as few "X-mas trees" as possible, i.e. no complicated branchings of the plumbing. 2: ALL seacocks should be positioned so that they are CONVENIENTLY accessible, lest they should be forgotten or become victims of the "It'll be alright just this time"-syndrome.

Seacocks that are exercised regularly do not seize up. Seacocks that get ignored because they are inaccessible WILL seize up.

PROPERLY installed, PROPER seacocks are not a threat to the ship.

TP

[jamhass]

One advantage of plumbing the foot pump to the engine inlet is in the event of a loss of raw-water flow to the engine, the foot pump can serve as a quick diagnostic. If the foot pump pumps, the line from (and including) the through-hull is likely clear. If it doesn't pump, look for an obstruction in the inlet line. May serve to avoid unnecessarily opening the raw-water pump.

[Jd1]

Do I see a regular hot dip galvanized cast iron tee in the second picture ? The second shutoff isn't even hot dip galvanized and is likely brass underneath.
Of course you don't have a proper thru hull either (why do it proper when you can do it cheap).

Scary stuff looking at that picture !!!!

[nautitrix]

This has been a good conversation with a wonderful variety of opinions and ideas.
For my own part I will instal the "t" on the raw water intake.
I will be attaching the line after the sea-cock which for me is easily accessible and less than 2 meters of hose to the tap in the sink.
I do not normally think of installing a check valve on any hose in a boat but this is
possibly the only place I can think of that will not cause any direct problems. The tap and the pump each stop air from entering the line while the engine is running and the check-valve is triple redundant with no bugs likely to crawl in and make it fail.
I agree that the particular engine does not, per se, matter too much, but an engine with the same coolant requirements is a good example to follow.
This was not my thread but it has served me well so thank you to the original poster and all the contributors.
BobV