Head stink

[markhunter]

Hi Peggie, I have read and re read your book, yet now feel it is time to get the expert opinion.
I have a Jabsco 37010 electric head that pumps straight into the holding tank. To empty the tank I can pump overboard or suck out via the waste on the deck. I have only just bought the yacht thus am still learning.
The entire fwd cabin and head have that male toilet smell, the holding tank pump is in the cabin, yet the holding tank is under the head itself.
Smell is intense in the cupboard behind the head, it has permutated through bunk cushions and everything in the fwd cabin too.
The vent line does not meet your specs, yet the yacht is 30 years old and am sure it hasn't been smelling for that long! The yacht perviously has a famous owner and a full time skipper! Also the vent line actually attaches to the stanchion which has holes drilled into it to enable airflow (I know that I should change this, yet don't Hinckley know what they are doing?)
I have removed the charcoal inline filter, which leaked when the tank was full. I have notived the syphon break valve leaks on pumping out the tank, this is in the cupboard mentioned earlier, as is the vent line.
I have resealed the syphon value with plumbers tape, so hopefully this has stopped, is that valve a replacable part?
I also notice that when I open the waste outlet on the deck, that is sucks in air suggesting the tank is not getting enough throught the vent. Generally I try to leave this open to compensate for the small and inadquate vent line, maybe I can rig a fan so it forces air into the tank?
Have sucessfully executed the hose smell test, and they were fine, thus the hoses are not the problem. Jocker changed and head itself performs perfectly.

The second head in the aft cabin is set up the same way, vent line and all, yet it has no smell.
Any hints as to what to do next.

ps. Amazon couldn't get your book even after I had paid for it, so I hope you received your cut and Amazon didn't just pocket my $. I found a copy in my local boat shop, so much for internet shopping.

Thx.

 

[Peggie Hall HeadMistress]

You have several problems

A blocked tank vent is only one of 'em. I suspect permeated hoses are another source of your odor, also residual odor from the leaking filter.

It would make sense to have water and fuel vent lines in rail stanchions on sailboats, because that prevents taking on sea water through the vents when the boat is heeled. It just never occurred to the builders or yards that what works for water and fuel doesn't work at all for for waste tanks. However, I doubt that Hinckley installed the tank. Your boat is 30 years old...tanks haven't been required in OZ nearly that long. But even if they did, that doesn't mean you have to keep it!

I also notice that when I open the waste outlet on the deck, that is sucks in air suggesting the tank is not getting enough throught the vent. Generally I try to leave this open to compensate for the small and inadquate vent line, maybe I can rig a fan so it forces air into the tank?

Nope...not the answer. However flushing the tank against a blocked vent will pressurize the tank, which can have very unpleasant consequences. A blocked vent can also cause a pumpout or macerator to pull a vacuum that prevents anything from being pulled out...a particularly strong pumpout can implode a tank. Replace the vent line with a new larger diameter line without any filter than goes to a proper thru-hull. That should eliminate the need for any fans or other devices to improve air flow. You'll use a Aussie product called the Uniseal UNISEAL (scroll through all the pages to see how it works...that's their US site, so you'll have to find their Australian source) to put a new larger vent fitting in the tanks.

The vented loop (anti-siphon device) most likely needs a new air valve, not plumbers tape!

Meanwhile, I wouldn't use the toilet again till you've solved ALL the problems.

The second head in the aft cabin is set up the same way, vent line and all, yet it has no smell.

My guess is, that toilet has always only flushed directly overboard, so any problems with tank venting would never have mattered. I wouldn't use it till I'd redesigned the vent, replaced the air valve and did all the preventive maintenance on that system too.

Getting rid of residual odors left behind after you've removed the source will be your biggest challenge. If you were in the US, I could tell you what products to use...but I don't know what's available in OZ. Locate a supplier of MICROBIAL (live bacteria)--NOT chemical!--pet accident odor eliminator. You'll prob'ly need at least a gallon, maybe two.

Put it full strength into a garden pump sprayer jug (a trigger sprayer will wear out your hand) and coat every surface, nook and cranny in areas that stink. Remove covers from cushions, spray the covers...saturate the foam from both sides with enough to penetrate to the middle. Do the same with any other soft goods, also musty PFDs and foulies...put it all outside in the sunshine to dry for a day.

That's enough to keep you busy for a day or two anyway...get back to me for more help when you're ready for it.

 

[markhunter]

Re: You have several problems

Thank you for your quick reply Peggie, I kind of knew that you would tell me to re do the vent lines. I will do what you suggest then let you know how I go. Might take a while as I am cruising thru QLD at present.
The Hinckley tanks were bulit in from new there completley glassed into the hull, no way to get them in or out! there are anly about 4 Hinckleys in Australia in total, so not a large export market forr them. Rgds Mark.