B361 odor under drop-in head fiberglass surround

Mar 30, 2017
3
Beneteau Oceanis 36 Pt. Richmond
A previous owner had an issue with an accidental discharge of the holding tank on our B361. There remains an odor we believe is residual from the accident, but are unable to access the bilge area due to the modular design of the head. The space between the hull and head is restricted to about 1/2 inch and horizontal access is limited by the stringers that do not allow the passage of fluids / cleaning utinsels into the area. Any suggestions for cleaning and/or reducing the odor to a location we cannot reach?
 
Jan 1, 2006
7,039
Slickcraft 26 Sailfish
I'm not versed on the construction of this boat but I will quote one of my instructors in my semi medical education - "The solution to pollution is dilution."
Can you flood the zone with water/bleach and pump out as quickly? If not, can you cut access to accomplish the same?
 
Dec 2, 1997
8,708
- - LIttle Rock
I see you've just joined our merry little band today...welcome aboard!

The holding tank spill may not be the source...so let's explore a bit. Odors are always strongest at their source, so it would be strongest where the spill occurred or where it ran to that the PO couldn't reach to clean it all up. So where did the spill occur--at the tank or somewhere in the plumbing? If not near the head, could a spill have run downhill to the area you think is suspect?

If it is under the head sole, it may be easier to clean up than you think 'cuz the stringers should have limber holes in 'em that'll let water drain into the bilge, letting you flush out that area. In which case you'll need to be able to flush it out very thoroughly with detergent and water followed by a thorough rinse to get rid of the soapy dirty water.

Or it may as simple as residual odor left behind in the areas that stinky sanitation hoses passed through...in which case it'll be easy to get rid of.

If you can rule out the spill or residual odor as the source, trapped water beneath a cabin sole is often the source of odors that can make a whole boat smell like a swamp or even a sewer...and you can drive yourself crazy trying to find the source....builders can neglect to create limber holes or they get clogged by degree or the gunk that's creating odor. So start by letting your nose lead you to the source...and the best time to do that is when you first come aboard. Don't start airing the boat out...do poke your nose into every locker, settee and other enclosed space...and the bilges.

Once we've nailed down the source for certain, we'll know how to get rid of it.
 
Jun 21, 2004
2,532
Beneteau 343 Slidell, LA
On the Beneteau's that I have sailed and the one that I own, there are no limber holes in the grid beneath the head/shower compartment. There is a drain in the fiberglass sole that drains all of the shower grey water into a sump that is defined by the grid and a pump that drains the sump. The grey water doesn't drain into the main bilge. So, if the holding tank spilled into the head/shower space, the crud is contained in the shower sump. The good news is that the spill affected a relatively small space ; the bad news is that you wont be able to access the sump to scrub it clean. That means that you will have to treat it as Peggy advised; do the "smell test" over the drain hole in the shower sole. If you confirm that is the location of the odor, flush it repeatedly with detergent and disinfectant and pump overboard and then finally rinse a few times with fresh water and repump. If you are averse to pumping overboard, you will have to visit a pump out facility and feed the pumpout hose into the shower space. Use a rubber nozzle on the pump out hose to obtain an adequate seal over the drain hole in the shower to at least get the bulk of the crud, detergent, and disinfectant out of the sump. Alternatively, you could also use a shop vac to vacuum the solution out of the drain hole. However, you are going to have to run some of the detergent / disinfectant thru the shower sump hose to rid the hose of stench. The 361's have been out of production for at least 10 years so you may have to replace all of the sanitation hoses also, if all else fails. Please let us know how it works out.
 
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Dec 2, 1997
8,708
- - LIttle Rock
I can't believe it never occurred to me that the area under the head sole is most likely a sump...I must have been more tired than I thought!

If the shower sump is the source of the odor, it's the easiest thing to clean....in fact, the only job on a boat that requires -0- manual labor! Raritan only markets their C.P. Cleans Potties as a bowl cleaner, but it's also the best sump and drain cleaner on the planet! C.P. is a bio-enzymatic cleaner that not only destroys odor on contact, but the enzymes "eat" hair, soap scum, body oils etc that clog up sump pumps. To use, run enough water down the shower drain to rinse out the sump, then enough water into it to cover the pump intake and put 2-3 oz of C.P. down the drain when it can stand at least overnight...'cuz the enzymes need time to work. There are no harmful chemicals in it, so it can actually remain in the sump indefinitely, so a good time to use it is last thing before leaving the boat. Just run some clean water through it when you return to rinse it out again. And btw, it's also the easiest way to keep sink drains running free and clean...close the seacock, put an ounce or two down the drain, then fill the rest of the drain with clean fresh water--again, when it can stand at least overnight. If you can find C.P. locally, the sbo.com online store has it.
 
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Oct 29, 2006
388
Beneteau 381 Olympia, WA
We have a 361 99 and I'm pretty sure there is no sump in the shower, the whole head is a molded "tub" and the shower drain is just a hose from tub that runs between it and the hull. I removed our black water tank years ago so feel vaguely familiar with that area of the boat, I replaced the tank with electro scan and never looked back. If black water made it down behind the head from the tank it's in a very inaccessible place. That said, at least on ours, it does drain out to main bilge. I had been messing with fresh water lines under sink and didn't tighten one so it slow leaked and water showed up in the small bilge compartment outside head under floorboard. I think you can pour water in there and it'll come out somewhere. Might be a good idea to loosen the tank a bit to see if you can inspect behind it, spending how serious the discharge was. Removing holding tank was surprisingly easy once I dug into it and got over my initial fear of black water plumbing, it will definitely give good access behind the head. Good luck, if they ban electro scan in my area I think I'll go composting :)
 
Mar 30, 2017
3
Beneteau Oceanis 36 Pt. Richmond
Hi Peggy,

Thanks so much for the insights. The B361's head sole drains directly to a hose connected to a shower pump. Which was not water tight when the boat was purchased, but the drain is on the forward side of the blocking stringer. The drain works well for liquids contained in the head sole, but does not help with trapped liquids beneath.

I am certain we also have hose permeation issues, but believe (based on staining and damage to vessel when shipped from NY to CA) that their was a larger unpleasant issue sometime in the past.

When purchased, the deck was not water tight and the bilge was a beautiful green. We could be mistaken in our assessment, and the odor could be mold combined with permeated hoses, but the stains and the way the bilge has been painted makes us suspicious.

In previous attempts to rid the smell from below the heads sink, we hve forced an ingestion of 4 or 5 gallons of water and cleaning solution without any of the liquid making it to the bilge. Will try putting her on a hard starboard tack tomorrow to see if we can displace the liquid.
 
Mar 30, 2017
3
Beneteau Oceanis 36 Pt. Richmond
Syverson, The B361 I have is a 2002. There is a stringer like structure that runs fore and aft between the lateral stringers creating an area that does not drain into the bilge proper, unless we have not hit it with enough water to reach a limber hole, etc. Thanks for the ideas. I have also inspected the holding tank mounting and found I could run a 1" down from there. Thanks for the advice!
 
Oct 29, 2006
388
Beneteau 381 Olympia, WA
I'll have to look at ours again, but you are right there are stringers fore aft under the head wall. The small bilge directly in front of the head door has a hole to drain the area under the sink though. It doesn't take much to drain as the leak I had under sink was tiny and I noticed very quickly there was water as that small bilge is where I keep my beer, making it the most checked bilge area on the boat...
 
Dec 29, 2013
4
Beneteau 393 Oceanis Savannah
We had a similar issue on our 393 (in the fwd head). After several attempts to clean, nothing seemed to work. I got frustrated and pulled a garden hose in through the hatch and sprayed the inner hull and kept flushing. Spraying from all possible angles I was able to dislodge several piles of errrrr........ biomatter! Kept flushing (again from several angles) for hours, keeping an eye on the limber holes and bilge. This finally did the trick.

s/v Luna Sea
www.sailinglunasea.com
 
Jun 2, 2004
149
Beneteau 393 Lake Texoma, Texas
Also a 393 owner that had some less than pleasant liquid leak under the head floor when changing out the primary discharge hose. Flushing it out with a hose as mentioned with the last post helped, but I followed with a generous supply of Natures Own that is available at pet stores to help reduce the odor once the fresh water water rinse was done. Worked well and no subsequent odor issues.
 
Dec 29, 2013
4
Beneteau 393 Oceanis Savannah
We used M9 which is used for colostomy bag odor. Either way yes, I had forgotten about using an enzyme on it.
 
Apr 5, 2017
1
Perry Catamaran 48 Coomera
For getting the odour eliminator into every place imaginable, I found this really nice portable shop fan from Ryobi that is in their rechargeable tool group. It is basically a small leaf blower.
I have the Pure Ayre mix in a 1/2 gallon garden sprayer, and fine mist the solution in front of the blower. (No picture of this as I cant hold everything and take a picture!) I tend not to use Natures Own or Natures Miracle, because these have warning about skin/eyecontact or breathing in the product, which PA does not have those issues.
It gets it everywhere, and works great for really getting it up into all of the isolated areas of the bilge and holds.