Whats with the gurgling sound?

[Bambooboat]

Hello wise forum,

We have recently purchased our new to us Carter Offshore 50, hopped onboard and have set out cruising. Very very steep learning curve in so many ways!! Coming now to 2 1/2 months aboard and here is my burning question:

The galley sink makes quite loud gurgling sounds. It kind of makes sense I guess as the drainage from the sink flows mostly straight out to a thruhull slightly above the waterline. But it is loud. Funny thing is that I hadn't heard it the first few weeks. I believe at some point I was cleaning the bottom and found barnacles inside the thruhulls so I cleaned them off with a stick/dowel. I believe the noise might have started (or gotten louder) then. Does this make sense?

Does anyone have this on their boats? Is this normal or is it maybe a sign of some incorrect installation I might need to address?

As always, your thought are greatly appreciated!

[atoll]

your sink acts like an amplifier for sound!

you could fit a u bend under the sink,or put the plug in the sink and leave some water in to keep the plug in place.

alternatively become a sailor and mentally tune out the sounds ,untill they stop,at which point you wake up when the sound changes.

[Privilege]

It's not an indication of improper installment...just a boat thing. Possibly the easiest fix is to put a one-way valve on the hose above the water-line just inside the thru hull. It'll stop the water from coming in and from gurgling as it leaves again.

[peghall]

Possibly the easiest fix is to put a one-way valve on the hose above the water-line just inside the thru-hull.

Maybe, maybe not. The water that goes down a galley sink drain contains any grease and/or oils used in cooking, even in the foods themselves. They build up on the drain walls, trapping food particles and lead to slow running drains and can clog a one-way valve even faster than the drain. If the noise is really objectionable, the best solution might be a seacock on the thru-hull even though it's above waterline. That would also make it a lot easier to clean the drain line by filling it with a cleaning solution to soak overnight.


--Peggie

[El Pinguino]

Put the plug in........

[Mr O]

Strang that the thru Hull for the sink is above the waterline. Should be below to eliminate the gurgling and keep the hull from getting an ugly stain. It could be moved next haulout but that’s a project. If you have easy access to the seacock, close it when you want quiet. A check valve might cause problems and I would not recommend it. Check valves are meant for pressurized systems and a sink drain may not have enough pressure to open. And it could get clogged.

[Privilege]

Originally Posted by Mr O

Strang that the thru Hull for the sink is above the waterline. Should be below to eliminate the gurgling and keep the hull from getting an ugly stain.

Sorry, but I can't agree with that. Why would you put a thru hull below the waterline when you don't have to? Sinks, aircon drain, locker drains, water-maker discharge, shower sumps etc...should all be above the waterline. Some one-way valves like the one above have a flap inside. If they are facing 'downhill' it needs no pressure to allow the escape of water and they will only close with the water trying to get in. I have these just inside the hull of each of my above water level thru hulls for this very reason. Bearing in mind that we are talking about water which is splashing up against the hull or being forced up there by waves, I'm not suggesting that they are suitable for below water level installations.

[sailingchiro]

I just shut my valve to the thru hull. I just need to remember to open it before we use the sink again. Mine makes that noise when we have waves coming at an odd angle such as current and wind are not aligned. We are on a cat and my thruhull for the sink is between the hulls. My opinion all thru hulls should have shut off valves but I digress.

[Bambooboat]

Thank you all for your views and comments! I will put a plug in place first and see how that goes :-)

[JPA Cate]

^^^
That should work. Works for us, when we go fast, the sinks gurgle. Plug in stops the gurgling, no extra water needed.

Ann