Question about permeated hoses

[sailing_sunrise]

Hi all-

New to the website. I have been working to tackle our head odor for quite some time. I have changed gaskets, O rings, siphon loop vents/duckbill valves to no avail. I have read Peggy Hall's book and use Odorlos for our tank and C.P. solution for our head. I have even run C.P. through the raw water intake for the head to clean out the bowl rim. We have an in-line sea strainer and that is clean/doesn't smell.

My question is, if the hoses are permeated...can it really create that bad of a smell? The smell happens probably 5-10 minutes after flushing and is a pretty rough sulfurous smell that fills the under sink compartments and head. It slowly goes away/minimizes over about an hour.

Thanks for your help! Pretty frustrated.

[peghall]

Welcome aboard the forum! And thanks for buying my book!



Yes, permeated hoses CAN be that bad. But your description makes me wonder whether hoses are the culprit, because permeated hoses aren't typically just a short section of hose that only stinks immediately after flushing...the entire hose from the toilet to tank--and prob'ly the tank discharge plumbing will be stinky all the time, causing the whole to boat to stink all the time.

So...some questions: Does the odor emanate from the toilet bowl or does it originate under the sink? If it originates under the sink, what else is under there...y-valve? Vented loop? Anything else that's a part of your sanitation system?
If it originates in the toilet bowl, does it happen with every flush or only the first flush or two when the toilet is used for the first time after the boat has sat for a few days or longer?

--Peggie

[sailing_sunrise]

Hi Peggie-

Here is the system:

1)Raw water intake to siphon(with vent) and sea strainer to head.

2) Discharge to vented siphon loop, to Y valve, to holding tank forward.


The smell is mainly in the under sink compartments in the head. Not in v- berth or holding tank area.

I have checked the one way duckbill valves and replaced one in the vented loops...still get the smell....another thought I had might be micro air leaks at fittings?

[NYSail]

There is a vented loop in your discharge? Wouldn’t that vent expell stink? I do see many diagrams with this setup though..... My system goes straight from bowl to tank with no vented loop in discharge and no stink (all new hoses and tank above water line).

Peggie to the rescue! Good luck......

Greg

[peghall]

Is the vented loop under the sink (which would be way too low for it on most monohull sailboats...but that's another topic)? What else is under the sink, including any connections?


--Peggie

[peghall]

There is a vented loop in your discharge? Wouldn’t that vent expell stink? I do see many diagrams with this setup though....

While a vented loop isn't needed in the toilet discharge line if it only flushes into the tank (although a loop can be useful when the run is uphill or the tank further from the toilet than the toilet can push it), a vented loop IS needed in any discharge line that connects to a below-waterline thru-hull. The air valve in it only opens in a line through which liquid is being PULLED...it stays closed in a line through which liquid is being pushed, so there shouldn't be any leakage or odor from the loop. That is, unless the air valve is worn out.

--Peggie

[Cpt Pat]

As with others here, I suspect the loop vent.

What you're smelling is hydrogen sulfide (H2S). The human nose is ultra sensitive to H2S. As it should be: very small concentrations (a few parts per million) can have health and cognitive effects. (See https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2199294/ for one example.) The insidious thing about H2S is, in a short time, it numbs your sense of smell, so it may seem to get better when it actually hasn't.

The hoses used with my "old" head were sufficiently permeable that the smell couldn't be completely eliminated. I replaced the hoses with mil-spec hydraulic line (expensive stuff). That seemed to help.

After finding I was devoting far too much time to fiddling with and fixing the head, especially when I had non-sailing guests aboard who would put things in it that didn't belong there -- despite my instructions (I think we all know what that was), I removed the head and substituted a camping toilet (fancy bucket) that uses waste bags. The ladies don't like it, but all the maintenance issues, and the H2S smell, vanished. I advise the ladies that the alternate head is via direct deposit at the shrouds. Yeah, it's not popular, but all my maintenance memories make me a bit brutal.

[smith8273]

OP, you never answered Peggy’s last question: does the smell only occur if the head has not been used for awhile. Mine gets that first flush smell if not flushed after about 8 hours, then not again until water sits in the intake for a spell.

[njoynthewater]

Not sure if this will help but it sounds a lot like our problem other than the location of the smell. Ours turned out to be from the vent hose fitting on the outside of the hull. When the toilet was flushed the air is displaced from the tank and out the vent. The odor would come back into the boat either through a port light or back in through the companionway. On our boat the vent hose dumps through the side of the hull about half way down the length of the boat. Being at anchor most of the time the wind is running down the hull.

[NYSail]

Originally Posted by smith8273

OP, you never answered Peggy’s last question: does the smell only occur if the head has not been used for awhile. Mine gets that first flush smell if not flushed after about 8 hours, then not again until water sits in the intake for a spell.

Love the smell of dead critters...... I am so happy with fresh water flushing!

[NorthCoastJoe]

I will be removing the head, hoses, tank and valves, entire assembly soon. If anyone wants any of it they can have it free, (tank will be empty)

I did the same on my Pearson 30, porta potty worked fine. No smells no pumpouts or thru hulls to deal with. Going to put in a composting head on this new to us Downeaster 38. Frees up a large amount of space and I am not hauling around 40 gallons ( 320 pounds ) of sloshing sewage. This is going to be done before we spend our first night on the boat, it smells now.

There are several people on here using composting heads. Reading their posts convinced me that is the way to go.Think of the weight and space savings, nothing to repair as well as no stink.

[peghall]

You might consider an "MSD" portapotty instead... The "MSD" designation in the model name/number means it has fittings for a pumpout line and vent line, and is designed to be permanently installed (actually just sturdier brackets than portables, so you could still take it off the boat if you absolutely have to), which means that although it's still called a PORTApotty, you don't have to carry anything off the boat to empty it.Yes, you'd still have to pump it out (or, by installing a y-valve and macerator or manual diaphragm pump in the discharge line, dump it at sea), but can't legally pour the urine containers overboard inside 3 miles and you'd be carrying bags of partially composted material off the boat about as often as you'd have to pump it out.


A 5-6 gallon model holds 50-60 flushes...you'd need at least a 30 gal tank to hold that many from a manual marine toilet. No plumbing needed except a vent line and pumpout hose--so no new holes in the boat...and -0- maintenance needed except for rinsing out the tank--which you can do with a bucket while it's being pumped out. Total cost including the pumpout hose and vent line is about $200--a fraction of what you'd spend for toilet, tank and all the related plumbing needed. And the best part is, you have all the advantages of a toilet and holding tank without giving up a single square foot of storage space.


Check out the Dometic/SeaLand 975MSD Sanipottie. There's also the Thetford 550P MSD, but it's been discontinued, although a lot of retailers still have it in stock.


Just a suggestion...go with whatever floats your boat for you.


--Peggie

[peghall]

There's a simple inexpensive cure for that can be done on any boat that has head sink and toilet on the same side of the keel and the head sink drains below waterline:

Reroute your toilet intake line to tee into the head sink drain line...the tee needs to be below waterline as close to the seacock as possible. Flush normally with sea water until you're ready to let the boat sit for a while. After you've closed the sink drain seacock, fill the sink with clean fresh water water...flush the toilet. Because the seacock is closed the toilet will pull the water from the sink, rinsing the sea water out of the inlet line, pump, channel in the rim of the bowl and the toilet discharge line.

Some boat builders used to plumb their boats this way because it eliminates one hole in the boat and saves 'em the cost of a thru-hull and seacock for the toilet intake. Tartan was one...it was a Tartan owner who gave me the idea in the mid '90s. A LOT of owners have done it and they all love it.


--Peggie