Toilet & sea water valve on cruise

MCNav

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I noticed while troubleshooting a waste tank pump issue that the sea water though-hull valve has always been opened on my boat. I checked the Owner's Manual and they recommend to keep the valve closed during cruise. Although it has remained opened for quite some time as it is difficult to access though the engine room, there was never really any excess sea water in the toilet. Are you guys and gals cruising with the toilet sea water valve opened or closed?
 
I hear you. I keep the waste tank valve closed and the sea water valve open. In my engine room it's a big of a pain in the butt to open the lift, go in there, turn the valve on just so someone can flush.

What are the dangers of running with it open all the time? Is it that sea water can creep into the toilet in rough waters making it overflow?
 
It rather depends upon the toilet and the installation.

Fitted with proper anti-syphon loops and valves there should be no problem.

The boat I crewed for many years has never had its toilet (Lavac ) sea-cocks closed in 30+ years.
A mistake because they are now seized solid but other than that no problems
 
We always keep the inlet seacock shut, at sea, anchor or marina. If you leave it open and you have a Jabsco whether you sink or not is determined by a little flapper valve that can jam open. Don't know about other toilets.
 
all seacocks closed when sailing......just because I can ...... having finally got them turning.
 
We always keep the inlet seacock shut, at sea, anchor or marina. If you leave it open and you have a Jabsco whether you sink or not is determined by a little flapper valve that can jam open.

Only if the installation is defective. My flush pipe is transparent, and I can see that most of it is empty of water. Short of serious pressure being applied to the outside of the skin fitting (like someone with a hose) there's nothing to drive water over the hump and into the bowl, valve or no valve.

I usually leave the toilet switch in the "wet" position as I've heard it's kinder on the rubber inside.

Pete
 
Only if the installation is defective. My flush pipe is transparent, and I can see that most of it is empty of water. Short of serious pressure being applied to the outside of the skin fitting (like someone with a hose) there's nothing to drive water over the hump and into the bowl, valve or no valve.

I usually leave the toilet switch in the "wet" position as I've heard it's kinder on the rubber inside.

Pete
I agree - ours are usually open and with anti siphon loops in both the hoses we never have a problem with unexpected siphoning.

Conversely I too have been on boats where it was necessary to shut the seacocks all the time. It all depends on the boat and the configuration of water levels, toilet installations and the way its plumbed.
 
>that little flapper valve is the joker valve

No it isn't, the joker valve is on the outlet side at the bottom of the toilet. Albeit if that blocks open there will be some backflow but not usually enough to sink the boat.

The flapper valve is the valve you move when you turn the switch from pump out to flush. That can sink you if the top of the bowl is below the waterline.
 
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