Galley and Head sinks Siphoning

[Bent Bugle]

Seasick lever?, wish I had one of those I could turn on & off, seriously though a good quality check valve would be fine, I've installed plenty of them, a ball valve on the outlet line under the sink is a good idea as well, especially if the thru-hull valve is a pain to access.

[MJH]

Originally Posted by blackjacobin

Hey amazing people, I have a SoutherCross 28 and when we are heeling to port both the galley and the head sinks siphon water, usually its not an issue the water stays in the sinks, but sometimes it does splash out a lot. I put rubber stoppers in the drains when we are going and that works but it can be a pain when we right and the suction really makes the stoppers hard to remove. I guess my question is: Is it a good idea to put a check valve in between the sink drain and the through hull?

Cpt Mike A., SV Katrinka

Some clarification is needed. Is the water fresh or salty...taste it. If fresh, where are the fresh water tanks located? Are both the head and galley sinks on the same side of the boat? Are they located outboard or centerline located.

I had a similar problem on my previous San Juan 28 and it took me years to figure it out until one day I went to the head while heavily heeled and saw water pouring from the spigot and missing the sink.

[wrwakefield]

As Mike mentioned, a properly installed purpose made pump will also solve these issues.

Whale makes a line of automatic diaphragm pumps specifically for this purpose, and no sump is required. And one pump can handle waste from multiple drains.

We are in our third year [full time cruisers] using the Whale Gulper 320 IC pump system for our shower drains [two heads with showers] and it would work equally well for sink drains...

These will pump anything that fits down the drain line, and empties the line because it keeps pumping for 10-15 seconds after there is no more water in the manifold (which is included with the pump.)

We put a drizzle of Rariton CP enzyme cleaner [which also removes soap scum...] down the drain every few weeks to keep them fresh and clean.

You can fit the pump near the discharge fitting [preferably high in the freeboard or transom] outboard of a vacuum breaker loop [as a fail-safe even though the Whale pump doesn't allow water to back-flow...]

Of course, closing the seacocks is cheaper, but also disables the sinks...

In case this is of interest.

Cheers, Bill

[nofacey]

Given your starting point, I like the idea of going straight to a pump & just pumping it out…..makes the sink work under all conditions, is easy to install and easy for everyone to use.
- I second the reliability of the gulper pumps, would be my go to for this application

[jt11791]

My head sink seacocks are difficult to operate, I can close them, but my wife can't. I installed a second ball valve right under the sink. It's easy to reach and operate and it is above the waterline when not heeled so it stays clean and easy to turn. It's our standard practice to close them when underway. Our galley sink drains to a graywater tank and is pumped overboard. Works fine so long as I can keep people from sending food down.

[Americanrancher]

Originally Posted by wrwakefield

As Mike mentioned, a properly installed purpose made pump will also solve these issues.

Whale makes a line of automatic diaphragm pumps specifically for this purpose, and no sump is required. And one pump can handle waste from multiple drains.

We are in our third year [full time cruisers] using the Whale Gulper 320 IC pump system for our shower drains [two heads with showers] and it would work equally well for sink drains...

These will pump anything that fits down the drain line, and empties the line because it keeps pumping for 10-15 seconds after there is no more water in the manifold (which is included with the pump.)

We put a drizzle of Rariton CP enzyme cleaner [which also removes soap scum...] down the drain every few weeks to keep them fresh and clean.

You can fit the pump near the discharge fitting [preferably high in the freeboard or transom] outboard of a vacuum breaker loop [as a fail-safe even though the Whale pump doesn't allow water to back-flow...]

Of course, closing the seacocks is cheaper, but also disables the sinks...

In case this is of interest.

Cheers, Bill

Thanks Bill, I have been thinking about doing this but I was concerned that I might be breaking some cardinal rule of not putting an electric pump in a drain line. The bottom of my galley sink is only slightly above the waterline and if the boat is healed severely on the Starboard side (Port Tack) sea water can back flow into the sink and even overflow the sink to flood a cabinet behind it. It's happened in the middle of the Pacific, not pretty! Closing the seacock can limit the flood but not stop it because the drain hose is full of seawater. I don't think a check valve will work either because the sink is so close to the WL, so no fall. I'd love to get my head sink into this solution but it is on the other side of the boat and I don't think I can route the plumbing properly to connect them. 2 pumps is getting a little too expensive for me.
Thanks, Ben
S/V DAWN in Tahiti

[wrwakefield]

Originally Posted by Americanrancher

Thanks Bill, I have been thinking about doing this but I was concerned that I might be breaking some cardinal rule of not putting an electric pump in a drain line. The bottom of my galley sink is only slightly above the waterline and if the boat is healed severely on the Starboard side (Port Tack) sea water can back flow into the sink and even overflow the sink to flood a cabinet behind it. It's happened in the middle of the Pacific, not pretty! Closing the seacock can limit the flood but not stop it because the drain hose is full of seawater. I don't think a check valve will work either because the sink is so close to the WL, so no fall. I'd love to get my head sink into this solution but it is on the other side of the boat and I don't think I can route the plumbing properly to connect them. 2 pumps is getting a little too expensive for me.
Thanks, Ben
S/V DAWN in Tahiti

Hi Ben,

I understand about the two pumps. We also had to do that because the two heads are too far apart for a single pump. However, I did rig the shower and sink drains in each head to a single pump, so I could repurpose the sink drain through-hulls...

The nice thing about the Whale IC pumps is the pump can be above the sink elevation. The only gravity flow required is to the IC manifold; the pump takes over from there.

I haven't been to Tahiti in 30+ years. Good memories. Enjoy creating yours...

Cheers, Bill

PS: If concerned about the sink being disabled if the pump fails, one could install a wye valve in the drain line to the original through-hull drain could be used as a back-up...