a different smelly heads problem

blueglass

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a different smelly heads problem

I have two heads with separate holding tanks fore & aft. The under sole compartments containing the holding tanks and associated pipework are impregnated with an odour which I can only describe as an unpleasant mixture of effluent and chemicals which I reckon originates from use of "Elsan Blue" type additive. It is a clinging smell which has now started to permeate adjacent wardrobes/ drawers etc. The boat is about 9 years old with the original pipework which is not of the new low odour type. Will the replacement of these pipes with low odour stuff (expensive/ unpleasant job) definitely rid me of the smell or is there going to be more to it than that? Have just searched forum on nasty niff syndromes from the heads. Useful stuff on the usual smell from stale seawater/rotting marine life etc in the intake pipe., but this is a different nasty niff. Is headmistress out there? I don't want to spend alot of time & money without some guarantee of success. I am confident root cause is holding tanks as both fore & aft compartments have identical smell, whereas the engine compartment sandwiched between them is fresh as a daisy, even though shower sumps etc are in there. Advice would be appreciated.
 
Re: a different smelly heads problem

From your description, I'm 99% certain that permeated sanitation hoses are the source of your odor. New ones should cure the problem. Just be sure to replace ALL of 'em, including the tank vent line.

But just to be sure, wet some clean rags in HOT water...wring 'em out and wrap one around a section of each hose. When the rag has cooled, remove it and smell it. If you smell the same odor on the rag, that hose has permeated. If you CAN'T smell anything on the rags, the hoses haven't permeated.

I'd money you'll smell it.

A few tips that might make this project a little easier--and a LOT less unpleasant:

Before beginning, pump out or dump your tank, then flush VERY thoroughly with plenty of water...it can be sea water. Also send plenty of water through the toilet to rinse out the head discharge hose...then some bleach or vinegar...let that stand for a few hours or even overnight.

To remove the old hoses (and put new ones on too), warm them first (I've always used a blow dryer)...they'll come off a lot easier. Don't use any sealant for the new ones...just double clamp, with screws on opposing sides of the hose--or at least 90 degrees apart if you don't have access to the "back side."

Before pulling any hose off, put a pan or garbage bag under each connection to catch any spill. Otherwise, you'll be back posting that the odor is not only still there, but worse than before!

Often, the easiest way to pull hoses through areas with difficult access is to pull the new hose through attached to the old hose. Cut the ends very cleanly...use a male-male connector...smear some PVC cement on the ends of the hoses...butt 'em onto the connector as tightly as you can get 'em...you want the smoothest unbroken surface possible so it can't get hung up on anything. Btw...duct tape will NOT work.

If you'd rather wait for cooler weather, you can buy some time by wrapping the hoses in Saran Wrap...has to be Saran, no other brand (I hope it's sold in the UK!) For some reason, it and no other is odor impermeable. I did this to my own, intending to change the hoses over the winter...it kept my v-berth odor free for another year.

Give another shout if I can help further.
 
Re: a different smelly heads problem

Hi Peggie,

I hope you don't live in N'awlins, now!

re: <<For some reason, it and no other is odor impermeable.>>

I read somewhere that Saran is polyvinylidene chloride and the others are polyvinyl chloride. The former is less permeable to small, smelly molecules.
 
Re: a different smelly heads problem

That IS extremely helpful - many thanks. Good tip on joining the new & old pipes together to pull through. I have been told that the new stuff has a slightly larger diameter so I am hoping that won't give me problems. I am thinking the smell will also be clinging to the GRP bulkheads/hull etc and may have a go with my wife's handheld steam cleaner around the whole place, followed by a long period of ventilation with all the hatches up. Can't say I am looking forward to the job, but it's got to be done before it inevitably gets worse. Thanks once again for such definitive advice.
 
Re: a different smelly heads problem

Hi Arthur...no, not in New Orleans, or even anywhere near ANY coast right now...something I've been lamenting till the increase in hurricanes. Not sure you're in a place I'd want to be either!


"I have been told that the new stuff has a slightly larger diameter so I am hoping that won't give me problems."

It will cause problems if the INNER diameter is larger, 'cuz it won't be tight enough fit on the fittings to seal. The solution: new fittings that are a tight enough fit that you'll have to warm the hose to get it onto 'em.

And btw, I forgot to include above: use a little dishwashing liquid--or better yet, K-Y surgical jelly--to lubricate so the fittings slide on more easily. Do NOT use Vaseline, oil or anything that isn't water soluble.

"I am thinking the smell will also be clinging to the GRP bulkheads/hull etc and may have a go with my wife's handheld steam cleaner around the whole place, followed by a long period of ventilation with all the hatches up."

Steam is likely to create humidity and warmth that will encourage new proliferation of odor from any bacteria or spores you happen to miss, especially in hard to ventilate nooks and crannies.

Go to a pet supply store and buy a microbial (live bacteria or enzyme--NOT chemical!) odor eliminator. Put it in a sprayer bottle (the pump up garden type works best)...spray ALL the affected surfaces...don't be stingy with it. Do not rinse...just let it dry. Leave all hatches open so that plenty of fresh air can circulate--run a fan if you can--for 24 hours. That should completely eliminate any residual odor for good.
 
More advice on flushing holding tanks

When flushing tanks, do you simply put a water hose into the on deck emptying point? Can't find any instructions and I don't want to bite off more than I can chew so to speak....
 
Re: More advice on flushing holding tanks

First, completely fill the tank with water. Pump that out or dump it. Then...

If you have an overboard discharge pump, putting a hose--NOT one used to fill the water tank!--into the deck pumpout fitting is the easiest way to flush it out. You can use a sea water washdown pump if you have one.

Fill the tank about 1/4 full...then turn on the pump and let it run while you contine to run water through for 10-15 minutes. To thoroughly flush out the hose to the deck fitting before removing it for replacement, put fill the tank again 1/4-1/3 full and PUMP that out, don't dump it.

If you don't have a means of dumping the tank, it's a bit more effort, but you still do essentially the same thing. Put water into the tank via the deck fitting, because that sends the water into the tank at the bottom to stir up any sludge. Again, fill the tank about 1/4 full...pump that out...put several more gallons in...pump that out...repeat till the water coming out is clean.

And btw, this should be done 2-3x/season--and especially in preparation for winter layup--as routine maintenance to get rid of sludge and rinse out the system.
 
Re: a different smelly heads problem

quote; It will cause problems if the INNER diameter is larger, 'cuz it won't be tight enough fit on the fittings to seal. The solution: new fittings that are a tight enough fit that you'll have to warm the hose to get it onto 'em.

The problem i was concerned with is OUTSIDE diameter, so new oipes difficult to pull through bulkhead apertures cut for the original pipes. I think I'm on my own with that one, but unfortunately some of those places extremely difficult to access without taking the boat apart. Does anybody know anything about the sizes of the new low odor stuff compared to the old. I can only imagine it is made in one size, at least for pleasure boats (as opposed to ships etc.)?
 
Re: a different smelly heads problem

The standard INNER diameter sizes for sanitation head and tank discharge hose is the same for all hoses...it's either 1.5" or 1" (whatever that is in mm). But the outer diameter varies due to wall thickness. Black double wall sanitation hose has considerably thicker walls--and therefore a larger outside diameter--than white sanitation hose...better quality white sanitation hose that's more permeation resistant (also a lot stiffer) has somewhat thicker walls than cheaper softer hose, but not as thick as black hose.

As for what will pass through the openings in the bulkheads on your boat, I'm afraid you are on your own to find out...'cuz there is no standard size for those.
 
Re: a different smelly heads problem

Sounds like the size differences are thankfully quite small so I will just have to suck it and see (?!)
One last thing - to make sure I don't get a recurring problem - the overriding element of the smell is I think from the powerful breakdown chemicals use as additives to holding tanks - brand leader over here is one called Elsan Blue. Is the use of this strictly necessary or is there an alternative?
And another last thing - replacing the pipes leading up to the deck pumpout point looks like the worst one to get to- impossible from inside - how are these fittings attached to the deck? can I for example loosen it at the deck end, attach new pipe to old as suggested and pull it through?
 
Re: a different smelly heads problem

I've never got my head round the idea, that smells escape from pipes, but not air or water. I am aware of the smells, it just dont seem feasable? /forums/images/graemlins/confused.gif
 
Re: a different smelly heads problem

[ QUOTE ]

One last thing - to make sure I don't get a recurring problem - the overriding element of the smell is I think from the powerful breakdown chemicals use as additives to holding tanks - brand leader over here is one called Elsan Blue.


[/ QUOTE ]

Actually, it's not the chemicals, it's the gasses produced by the breakdown of sewage in the anaerobic environment inside the hoses. The best way to extend the odorless life of hoses (not even the very best last forever, though) is to ALWAYS run clean fresh water through 'em to rinse 'em out before the boat is to sit. A cupful of white vinegar through 'em once a week will also help to retard odor, while preventing sea water mineral buildup.

"And another last thing - replacing the pipes leading up to the deck pumpout point looks like the worst one to get to- impossible from inside - how are these fittings attached to the deck? can I for example loosen it at the deck end, attach new pipe to old as suggested and pull it through?"

Like all deck fittings, your pumpout fitting is secured with screws and then bedded. If there's NO other way to get to that end of the pumpout hose, you may or may not be able to remove it and pull it up to replace the hose, then screw it back down and rebed it. The only problem is the hose clamps: will they go through the hole in the deck? Most likely they won't. The only solution: loosen 'em and let 'em fall before pulling the hose out...make sure to put 'em back over the end of the new hose before you attach the hose to the deck fitting. Then you'll have the fun of trying to move 'em up and tighten 'em in a place you can't get to. /forums/images/graemlins/tongue.gif

One caveat: make sure that the screws will still be a tight fit when you put the fitting back down...if not, fill the holes and drill new pilot holes.

As for the question of why hoses soak up odor, but not waste or water...hoses do absorb SOME liquid, but not nearly at the same rate they absorb gasses. The thicker the hose wall, and the tighter the molecules in the hose material (which explains why more odor-resistant hoses are considerably stiffer than those that permeate easily), the slower either happens...conversely, the thinner and softer the hose, the faster the absorb both. Gasses make themselves known very easily...you'd need a highly sophisticated moisture meter to measure the rate of water or waste absorption.
 
Re: a different smelly heads problem

.

But just to be sure, wet some clean rags in HOT water...wring 'em out and wrap one around a section of each hose. When the rag has cooled, remove it and smell it. If you smell the same odor on the rag, that hose has permeated. If you CAN'T smell anything on the rags, the hoses haven't permeated.

Peggie,
Just back from the boat ( it's 250 miles away and don't get to it as often as I would like!) I have tried the wet rag test on 3 or 4 of the pipes and not a trace of the smell is transferred - I was really surprised.
Am now thing of installing an extraction fan in the affected compartments, and spraying out with the microbial treatment you mentioned. What do you think? ( do you know any brand names or key active ingredients to check for?
Thanks,
Dave
 
Re: a different smelly heads problem

Damn...I'd have bet money on the hoses! I wonder if they were replaced shortly before you bought the boat, resulting in a few little spills...that would cause your problem.

If you were in the US, I could recommend a couple of microbial products by brand name...but I don't know what's available in the UK. Go to any pet supply store and ask for a microbial (specificy microbial only) odor remover for accident sites. Get the largest size. Put in a spray bottle (the pump garden spray bottles are dandy for this)...spray it EVERYWHERE odors are strongest immediately after opening up the boat. Just let it dry...keep all lockers and hatches open...turn a fan on if possible...for 24 hours.

If THAT doesn't do it, we need to start looking for trapped water below the sole somewhere....'cuz trapped water left to sit and stagnate will smell like a sewer.

Btw...I'm assuming that you've already cleaned the sumps? Wet dirty sumps can smell like a sewer too.
 
Re: a different smelly heads problem

I know you checked the hoses - but what sort of hose is it?

have seen many boats (incl mine) which use the clearish pvc with steel wire reinforcement.

IF yours are this type, I'd change them anyway,even if they passed the rag test. certainly the ones we have/had are porous enogh to odour that they'll let it through v.quickly , yet once flushed through, the hose itself smells ok, leaving an odour in the area, seemingly not from the hoses.

If you change them, avoid the cheap'ish stiff white hose sold in many chandlers for hard to reach areas - it can be the very devil to fit over spigots, even with heat,lubrication etc. Vetus stuff ,or any black liner'd hose, usually much easier to fit.

Also, what material are the tanks made of?
 
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