Brownish and smelly bilge water

Hi folks…
I´m having a problem with bilge water settling tank, all the water is brownish and smell is very bad. Oil is settling out good and OWS also works but filters gets clogged faster than normal. First
I was thinking that it will clear by time and more water but it´s not working. This has happened before and that time emptying and cleaning the tank helped but I would like to understand what´s going on.
Is it possible that there is some kind of bacteria that causes this? We had to pump some seawater in the tank earlier, could this have something to do with it?
Any ideas or experiences?

I’m afraid I can’t offer any suggestions but I know your pain…

I’ve no idea at all what it is that grows in the bilges of the ORCA but I fear the day will come when it rises up and takes over the planet…

Every now and then I get the idea to sell everything and start living aboard a boat. Then I remember that smell. Hard to find one that doesnt have that unmistakable stench when you lift up the floorboards. Let me know how you solve the problem. Until then its strictly day sailing.

[QUOTE=salt’n steel;150432]Every now and then I get the idea to sell everything and start living aboard a boat. Then I remember that smell. Hard to find one that doesnt have that unmistakable stench when you lift up the floorboards. Let me know how you solve the problem. Until then its strictly day sailing.[/QUOTE]

I lived for three years on a 1941 vintage wooden boat back in the 80’s and believe me the winters was a hellish world of dampness and the ever present odor of diesel. On one’s clothes, the pages of books and in the food even. It made for a very difficult task to find a lady to date…the smells and the ranting usually drove them screaming into the night. Summers were much more pleasant though and then lady who eventually became my wife actually thought I lived the coolest life any man could have. Turned out she had a thing for detective stories and thought I was the embodiment of Travis McGee living large on the BUSTED FLUSH in the Bahia Mar Yacht Harbor in Fort Liquordale

…I wished!

[QUOTE=miketm;150430]Hi folks…
I´m having a problem with bilge water settling tank, all the water is brownish and smell is very bad. Oil is settling out good and OWS also works but filters gets clogged faster than normal. First
I was thinking that it will clear by time and more water but it´s not working. This has happened before and that time emptying and cleaning the tank helped but I would like to understand what´s going on.
Is it possible that there is some kind of bacteria that causes this? We had to pump some seawater in the tank earlier, could this have something to do with it?
Any ideas or experiences?[/QUOTE]

I’ve run into something similar, it was bacteria. Got rid of it by dumping some bleach down the sounding tube of the bilge water tank and adding some to each bilge well once a week. I don’t remember the dosage amount.

What you are dealing with is anaerobic decomposition of petroleum distillates. Similar to a septic tank, this bacteria gives off a foul, septic, sulfur 'rotten egg" odor. It also possesses a slime which will foul filters.

Couple things you can do. First, try to minimize the quantity of oil contained is the dark recesses of the bilge. You can then add bleach , but it is short acting. I might suggest dropping a few chlorine/bromine tablets in there for a bit more staying power. Any swimming pool supply house can set you up.

Works like a charm every damn time, I swear by it!

[ATTACH]4130[/ATTACH]

Hoping this picture goes thru. My boat reading material not as sophisticated.

Sure it is brownish or more blackish? It is bacteria and anaerobic but probably has little to do with oil residues. The critters that usually cause the rotten egg smell due to an anaerobic process are usually the sulfate reducing bacteria (SRB). They also generate bio-slimes. This is the black stuff that can clog filters pre, inside or post the OWS. These solids will plate out on coalescing filters and really make a mess of things. They live in sea water and actually can get the iron from exposed steel (are your tanks coated?) involved in the process. Google sulfate reducing bacteria if you want more on the chemistry involved.

Some of the things I’ve tried are, fitting a bubbler manifold in the bottom of the BHT. I have air bubble in the tank while collecting bilge water. Actually made it work on a timer so it doesn’t agitate the tank too much. The anaerobic bacteria cant live with the oxygen. When I want to process a batch through the OWS I secure the air, let the tank settle a bit first then process as usual. Chlorax or the stronger concentrations of chlorine solutions did not seem to work on this particular type of bacteria but I did try it for a while. Really did not work and who knows what else it is doing to the tank. I did find a Drew biocide called “biosperse” that I treat the BHT with a couple times a week as the water accumulates in the BHT. The combination of aeration and that product seems to keep it in check mostly. Another thing seems to be time spent in the tank so don’t let it stand too long. Collect and process in small batches as it accumulates. Unfortunately heat, while good for separation also seems to promote the critters growth rate and the more of them the more waste products they produce (bio slimes). As with the air, you can collect and aerate a batch, turn off the air, turn on the heat, let it stand for a few hours, turn off the heat allow to settle a bit more and then process with the BHT. Good luck.

Agree with the above comments BUT there is sulfur in some oils. Also, scavaging sulfur from uncoated steel is not essential. I know this from summers on my Dad’s boat. It had a fiberglass bilge below a pair of leaky 6-71 Detroit Diesels. It left unchecked, by September there would be some truly nasty odors down there.

Our fix was a combo of oil sorb blankets, detergent, pressure washing, and a bit of chlorine via bleach or pool tablets.

Thinking this through a bit more, this was about 10 years ago when diesel had sulfur. Not sure if the same applies today now that most the sulfur is gone.

Great fix idea. Agree on the chem treatment too.

We use it but I like the air feed idea a lot.

Successful elimination of this nasty smell in a steel, fiberglass or wood engine room requires wiping all the oil drips. Keep the water out, run a dry engine room and your smell will go away. Like Jet, fiberglass is best, with white containments. A drip of oil can be spotted a mile away in an all white engine room and make monitoring much easier. With wood take a wet vac with a long attachment to the hose and suck the LAST bit of water out, transfer into a barrel or empty fives and use diapers wherever needed. A thorough cleaning is required first.

s[QUOTE=Jetryder223;150477]Agree with the above comments BUT there is sulfur in some oils. Also, scavaging sulfur from uncoated steel is not essential. I know this from summers on my Dad’s boat. It had a fiberglass bilge below a pair of leaky 6-71 Detroit Diesels. It left unchecked, by September there would be some truly nasty odors down there.

Our fix was a combo of oil sorb blankets, detergent, pressure washing, and a bit of chlorine via bleach or pool tablets.

Thinking this through a bit more, this was about 10 years ago when diesel had sulfur. Not sure if the same applies today now that most the sulfur is gone.[/QUOTE]

[QUOTE=seacomber;150497]With wood take a wet vac with a long attachment to the hose and suck the LAST bit of water out, transfer into a barrel or empty fives and use diapers wherever needed. A thorough cleaning is required first.[/QUOTE]

do you have any idea at all how unrealistic all that is? they’re wood boats for God’s sake…it is impossible to vac every last bit of water out because once you do, more water follows and forget the getting the bilges all spit and polish clean. A garden hose and detergent is the best I can muster ever few months…

so here’s a question for the panel…isn’t wood protected when impregnated with oil?

Sea water and oil are good for wood, fresh water is a killer. I don’t see you getting down there and mucking the sludge out, I have done it on three boats. I will not be doing it again…there are times when I thought about saying the hell with it, the worst one was done with a putty knife laying flat and reaching every bit I could, nasty shit. after getting the majority out, I took a steam cleaner to it and pushed the rest to the back of the engine room, this was a good spot to get the remainder. then another washdown and rinse, the water you speak of is always coming in but locating where is part of the fun and trying to stop it is the rest. It all sounds unrealistic and for old farts it is, so hire a young buck and get that shit out of your bilge, fix the leaks and then you wont have to listen to stupid assholes like me telling you how to run your boat.

[QUOTE=c.captain;150498]do you have any idea at all how unrealistic all that is? they’re wood boats for God’s sake…it is impossible to vac every last bit of water out because once you do, more water follows and forget the getting the bilges all spit and polish clean. A garden hose and detergent is the best I can muster ever few months…

so here’s a question for the panel…isn’t wood protected when impregnated with oil?[/QUOTE]

[QUOTE=seacomber;150500]Sea water and oil are good for wood, fresh water is a killer. …then you wont have to listen to stupid assholes like me telling you how to run your boat.[/QUOTE]

Well being my boat sits in Puget Sound I have salt water in the bilges and being that it is powered with a Detroit, I also have plenty of oil so I’m good to go (at least until the black slime monster rises and kills me when I am not looking)

also you don’t have to worry about telling me how to run my boat…I wouldn’t listen to you anyway!

Strike my word run, I meant clean. You are right, you are good to go with salt and oil and scented candles.

[QUOTE=c.captain;150501]Well being my boat sits in Puget Sound I have salt water in the bilges and being that it is powered with a Detroit, I also have plenty of oil so I’m good to go (at least until the black slime monster rises and kills me when I am not looking)

also you don’t have to worry about telling me how to run my boat…I wouldn’t listen to you anyway![/QUOTE]

Is the [I]Orca[/I] wooden hull? I thought she was aluminum.

[QUOTE=txwooley;150518]Is the [I]Orca[/I] wooden hull? I thought she was aluminum.[/QUOTE]

ESTERO is the 30’ aluminum Monarch you’re thinking of…

ORCA is a 45’ fir on oak trawler hull built in 1962 in Bellingham