Toilet, how to get the seawater out of the inlet pipe

simonfraser

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Jabsco setup.
I rinse the bowl and outlet hose with fresh so no smells when I return.
Just pour fresh water in the bowl.

But the stagnant water in the inlet smells when I return, no big deal.
Is most of it in the pipe rather than the pump ?
Recon most of it would drain out if I let some air into the inlet pipe, fit a valve ?
 
Simon, you are declaring war on Biology. I fear you will lose.

Upon arrival, open the valves, flush the bog well, and ventilate the boat. Your aim is to get seawater with dissolved oxygen back in the system. It's only a 5 min job.
 
Jabsco setup.
I rinse the bowl and outlet hose with fresh so no smells when I return.
Just pour fresh water in the bowl.

But the stagnant water in the inlet smells when I return, no big deal.
Is most of it in the pipe rather than the pump ?
Recon most of it would drain out if I let some air into the inlet pipe, fit a valve ?

I fitted a tankette (http://www.tankette.com) in a loop above waterline just after the toilet inlet. If I leave the boat for a while, I unscrew the top of the tankette and pump all the water out of the inlet hose.

The tankette bullets really do work well too. The manufacturers claim lots of magic properties, and mostly they do seem true. They kill anaerobic bacteria so noticeably reduce smells. They supposedly reduce calcite deposits in the outlet pipes. They make the flush water blue which looks cool but also allows instant diagnosis of the source of an occasional flooded bowl.
 
I have connected the toilet inlet hose and the sink outlet together with two tees and value.
Close both toilet inlet and sink outlet open connection valve fill sink with fresh water and pump.
Easy to flush both toilet with fresh water. Winterizing is also much easier...
 
I have connected the toilet inlet hose and the sink outlet together with two tees and value.
Close both toilet inlet and sink outlet open connection valve fill sink with fresh water and pump.
Easy to flush both toilet with fresh water. Winterizing is also much easier...
Our boat was designed with a similar setup from new. We have the wash hand basin with a conventional seacock. After the seacock is a bronze tee that splits the connection between toilet inlet and the sink waste. To flush the toilet with freshwater, simply close the seacock and fill the sink. Works very well.
 
All of the above contrived and fancy solutions are unnecessary in my experience if you flush the toilet REALLY well before you leave the boat. By really well I mean pump and keep pumping to ensure no waste either gets pumped back in and any that gets past the piston in the pump back into the inlet side is well flushed away.

Plain seawater doesn't smell. Seawater contaminated with sewage does.
 
All of the above contrived and fancy solutions are unnecessary in my experience if you flush the toilet REALLY well before you leave the boat. By really well I mean pump and keep pumping to ensure no waste either gets pumped back in and any that gets past the piston in the pump back into the inlet side is well flushed away.

Plain seawater doesn't smell. Seawater contaminated with sewage does.

+1 on T-pieces and valve. Our forward head used to smell but is now fine for at least 8 weeks before needing a fresh water flush.

A lot depends on position of inlet and outlet fittings. Aft head was never a problem, only forward head. Forward head mainly for pee and always gets 24-30 pumps to flush. Aft head goes to holding tank so only opened underway when inlet will be in clear water.

Just pumping a lot doesn't guarantee a smell free inlet pipe but does inhibit calcification. Pumping whilst underway will help but you may still pull in the odd bit of weed.
 
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+1 on T-pieces and valve. Our forward head used to smell but is now fine for at least 8 weeks before needing a fresh water flush.

A lot depends on position of inlet and outlet fittings. ...

Just pumping a lot doesn't guarantee a smell free inlet pipe but does inhibit calcification. Pumping whilst underway will help but you may still pull in the odd bit of weed.

I sometimes forget that not everyone boats in tidal waters. A good tidal stream past the boat ensures what goes out doesn't come back in. The only alternative is to pump lots while under way.
 
Jabsco setup.
I rinse the bowl and outlet hose with fresh so no smells when I return.
Just pour fresh water in the bowl.

But the stagnant water in the inlet smells when I return, no big deal.
Is most of it in the pipe rather than the pump ?
Recon most of it would drain out if I let some air into the inlet pipe, fit a valve ?

The solution which costs less than £10 and lasts forever is in post #19. http://www.ybw.com/forums/showthread...let-pipe-smell

Problem gone permanently. No valve switching required. End of. ;)

Richard
 
But the stagnant water in the inlet smells when I return, no big deal.
Is most of it in the pipe rather than the pump ?
Recon most of it would drain out if I let some air into the inlet pipe, fit a valve ?

It's water left in the pipe. If you've pumped the bowl dry, there'll be no intake water in the pump.

You could fit a valve, but any water will only drain down to sea level, so you'll never get rid of all of it.
 
I sometimes forget that not everyone boats in tidal waters. A good tidal stream past the boat ensures what goes out doesn't come back in. The only alternative is to pump lots while under way.
We have found that leaving the boat for a week or more in hot weather the inlet pipe would get smelly due to saltwater having dying plankton in it. Flushing with fresh water before leaving the boat makes a difference
 
We have found that leaving the boat for a week or more in hot weather the inlet pipe would get smelly due to saltwater having dying plankton in it. Flushing with fresh water before leaving the boat makes a difference

It's not the plankton. Try putting some seawater in a bottle and leave it lying about for a few days. It doesn't smell.

The smell is from effluent either being circulated back into the inlet pipe from the discharge underwater or leaking past the piston in the pump.
 
Not when it's in the sea. But when it's left for several days in the inlet pipe of the toilet, anaerobic bacteria in the water break down and cause a "rotten egg" smell which is released to the atmosphere the first time the toilet is flushed.

I think it may depend on the purity or otherwise of the seawater in which you sail. I have never experienced any nasty smells from the inlet water, no matter how long it's been left in the pipe. (West Coast of Scotland).

The inlet seacock is also on the opposite side from the outlet. :rolleyes:
 
The smell is from effluent either being circulated back into the inlet pipe from the discharge underwater or leaking past the piston in the pump.

Interesting. So how would it happen when the toilet is being discharged into a holding tank? And how would water "leaking past the piston in the pump" find its way into the inlet pipe?
 
I think it may depend on the purity or otherwise of the seawater in which you sail. I have never experienced any nasty smells from the inlet water, no matter how long it's been left in the pipe. (West Coast of Scotland).

You're probably right. Many of us sail in crowded (read "polluted") waters.
 
Interesting. So how would it happen when the toilet is being discharged into a holding tank? And how would water "leaking past the piston in the pump" find its way into the inlet pipe?

It's finding its way back into the end of the inlet pipe which is in the pump head and in the pump itself. It's why the "urinal block" solution works 100% effectively as the block disinfects everything downstream of the filter which includes the entire length of the inlet pipe and the entire pump housing.

If you already have the inline filter it's a no-brainer guaranteed solution as the blocks cost peanuts and last for years. If you don't have the filter, the Jabsco one is £8 or something. ;)

Richard
 
It's finding its way back into the end of the inlet pipe which is in the pump head and in the pump itself.

There's a weighted valve closing off the end of the inlet pipe. It's anaerobic bacteria in the seawater which cause the smell. I'm not concerned, as the inlet pipe on my boat is very short, and I don't notice any nasty smells, even when the boat's been unoccupied for a week or so.
 
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