Chemicals and seacocks

[eddystone]

My galley sink has become blocked. So far I have only tried boiling water and a length of cable without success. Next time I will try boiling water again but also use a suction plunger. I'm reluctant to attempt to remove the hose from the seacock whilst in the water - the similar one in the heads needed cutting off. My daughter suggested bicarbonate of soda - mixing it with white vinegar makes for a vigorous reaction but I guess boiling water would also do. I can't think bicarb can harm a seacock?

 

[Tranona]

No harm to seacock material.

 

[RivalRedwing]

Bicarb is a gentle (alkaline) abrasive and when mixed with an acid (vinegar) it will fizz, making your vinegar less acidic... little harm to a seacock but also unlikely to have much effect on your blockage. Hopefully the plunger will be your friend.

 

[Pye_End]

Remove the hose from the sink, and bend it over, below the water line, into a bucket. If this still doesn't work, rod it down the pipe, or us a dinghy pump on the pipe to blow it through.

 

[vyv_cox]

Caustic soda is the usual household chemical for unblocking drains but nasty stuff to have on board. Mechanical methods seem more appropriate.

 

[thinwater]

Bicarb is a gentle (alkaline) abrasive and when mixed with an acid (vinegar) it will fizz, making your vinegar less acidic... little harm to a seacock but also unlikely to have much effect on your blockage. Hopefully the plunger will be your friend.

That is not how it works.

The bicarb is allowed to soak into the blockage. When the vinegar mixes with it it fizzes ... behind the blockage, physically pushing it off and breaking it up from within. It is the physical action of the bubbles behind the deposits that does the work. The longer the bicarb soaks (within reason) the deeper the bubbles form.

I didn't understand it at first either.

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There may be hard growth in the mouth of the seacock. Does the handle turn easily? If not, you need to go for a swim with a screwdriver and remove the barnacles. Common.

 

[davidej]

Are you absolutely sure that this is a blockage rather than the seacock sticking closed. With some types of cocks, the actuating axle can break and you can move the handle to open without the ball moving.

 

[eddystone]

Are you absolutely sure that this is a blockage rather than the seacock sticking closed. With some types of cocks, the actuating axle can break and you can move the handle to open without the ball moving.

No that is a possibility as ball valve is over 10 years old - unlike all the others which are Blakes just can’t see; although maybe blocked by fouling more likely. It’s because I don’t have total faith in the seasick that I wouldn’t contemplate cutting the hose off whilst boat is in the water

 

[rogerthebodger]

Is your gally sink sea cock above waterline of below water line.

If its above water line, no problem in removing the hose from the seacock.

If its below the waterline you could just remove the pipe from the sink outlet and the lower the pipe until you can push a rad along the pipe and out through the open seacock

You could also knock a wood tapered plug into the outlet from the outside to stop any inrush of water

 

[James_Calvert]

If it's like my Sadler 32, the seacock is directly below the sink in a straight line from its outlet. And below the waterline.

Surprised you couldnt shift the blockage by poking at it. On mine a straightened wire coat hanger is just long enough. But sticking the dinghy pump nozzle into the sink drain, and jumping onto the pump can also work.

Apart from a failed seacock, which you should be able to diagnose from the length of wire going into the drain, have you any idea what blocked it? The first few inches from the bottom of the hose will normally be full of seawater. If fat is poured down the sink, it can solidify there. Maybe boiling water might help shift it.