Sewage smell ....

jff

jff

Member
Mar 29, 2008
510
Atlanta
Boat Info
2017 Crest Pontoon
Engines
Yamaha
We noticed today a sewage smell in the salon area, hard to tell where it is coming from. A few facts:

- our holding tank is near empty and hasn't been more than 1/2 full in the last month
- we replaced the vent filter in the bilge about a month ago
- we noticed the smell after a long run (150 miles)

I'm thinking just some gas somehow escaped but I'm wondering what the full range of possibilities (and ideally accompanying solutions) are?

Regards,
Jason
 
First, go back and check all the clamps and connections for the vent filter. In fact, remove the hoses from the filter, and check to see if you inadvertently left one of the end plugs in (little red cup). Don't ask...........
 
I'll go check, but if that were the case wouldn't this problem have manifested itself in the past 45 days (the filter was replaced about 45 days ago)?

Regards,
Jason
 
Not really, my 390 does it whenever it feels like it. We could go weeks with no problem then open the door and there it was. I have rebuilt the head, replaced hoses, filter, and vacuflush pumps. I'm suspecting the vacuum canister could some be doing it now. Before I sell it I 've got to fix it. Good Luck
 
It may not be your holding tank but your sump box. If you get a funky sump box, the odor/gas will come up through the sink drains, shower drains, etc. It happens to me all the time. Poor a little bleach down a sink or shower drain and see if that clears it up.... then pop open your sump box and give it a good cleaning.

It's good to put a little laundry soap or bilge cleaner down the drain if you are leaving the boat for very long. You don't want to leave bleach in it as it will eat up the 1-way whale valves on it...

If that is not it and you still have a sewage odor, it could be a few things. The one time I had a real sewage odor was because the kids were not flushing the toilet and the o-ring seal on the toilet was all nastied up (they are porous and absorb stuff). The o-ring on the toilet is actually two halves and are like two pancakes on top of one another. One hole is bigger on one of the rubber pancakes than the other and the white ball that flushes the toilet is in the middle of these rubber o-rings/pancakes. The problem is if there is poop or pee left in the toilet and one of the seals leaks a little, it can get in between the two rubber pancakes... and start to stink.

So... I would try the sump box first... and then go after the rubber seals on the toilet next....

Remember... the "If it's yellow let it mellow and if it's brown flush it down" is a very very bad practice on a boat.
 
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Vent filters are sometimes more trouble than they're worth. It'll back up tank gasses if it gets saturated, either from the waste tank or from the outside vent fitting (like from being turned the wrong way into spray, or during washdown). Don't know where it's situated on a 48 though, but double-check it and make sure it's still allowing air to pass through it. I've practically given up on using one and just put a section of hose with fittings in it's place. Enough time up on plane and the tilt seems to lead to waste water getting back to the filter. Can't hurt to recheck the filter.

It would be unusual for the hose on an '05 to be permeated through yet. But if waste is left in the hoses/tank for too long the smell can leech it's way through the wall of the hoses. But you would've probably already noticed the smell if that was the case.
 
I'm with Gary on this. I have to clean our sump from time to time. I know right away when its ncessary. Usually after the boat has set after an extended use. What I do is flush the system with water before we leave, that way only water is left sitting in the sump.
 
Four Suns said:
Remember... the "If it's yellow let it mellow and if it's brown flush it down" is a very very bad practice on a boat.
Click to expand...

Gary, what you do at night time (sleep time) on the boat?
The vacuflush system is loud as you flush it.
We tend to do the yellow / mellow thing during sleeping hours.
 
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It may very well be the hose going from the bowl to the vacuum unit. It does not have to leak to smell. There is a membrane in the hose to keep this from happening. Sometimes the membrane breaks down causing the hose to smell. Take a clean rag, rub it on the hose and take a sniff . that should help you find the problem.
 
I had the same smell and it seemed to get worse when we moved the boat. I had pumped and rinsed several times and replaced the vent filter. I was not having the typical problem of having the smell after a flush. My problem ended up being water that had become trapped between my hull and the subflooring. I never saw an appreciable amount of water in the bilge. Then the odor was so bad I smelled the water in the bilge and it was foul. I removed the water and came back in an hour or so and there was more water only to find that the water was seeping up through a screw that was fastening the pump to the floor. Long story but somehow I got lots of water that was hidden and it festered and smelt worse than the sewage. I hope this is not your problem.
 
Another possibility is that you may have a bad battery. Just happened to me. Thought the sulfery smell was the head but it all checked out OK. Noticed some of the first mates jewelry had also become tarnished so I did a internet search and came up with a forum that talked about smell and tarnish. Seems a bad battery will give off a gas (hydrogen sulfide) which smells like a cross between a rotten egg and a burnt match. Changed the bad battery and voila no more smell.
 
FWIW, i have the same central sump tank as Gary, and if that gets gooped up, the overflow is to the central emergency sump under the S/B stateroom. That is the cause of my "random" bad smells on the boat.
 
MadDog said:
FWIW, i have the same central sump tank as Gary, and if that gets gooped up, the overflow is to the central emergency sump under the S/B stateroom. That is the cause of my "random" bad smells on the boat.
Click to expand...

I have the exact same issue. When I first purchased the boat the sump chest pump was down and so was the bilge pump. The grey water was just sitting in the bilge smelling up everything as it had overflowed from the sump box. Changed the pumps and all was Ok for a while. The smell comes and goes. I just cleaned out my sump 3 months ago but I think its time to do it again.

Jack
 
Jason

I had the same thing.. check the sallon bilge pump area (the hatch just below the TV cabinet, if there is water there it is the foul water coming out the overflow tube of the sump box.

The problem: the sump box looks like a V8 sump, with the pump in the lowest part but (stupidly) the float switch is 3-4 inches higher, so the sump never empties. when you go up on plane there is enough of this foul grey water to spill into the blige but it's not enough to set off the pump (which sets off the high water alarm). it festers in the heat.

I ripped out the float and pump and installed a Rule 2000 with built in float. My sump pumps DRY. once I did this and cleaned the sump box, I don't even get the black mold anymore. The box is DRY.
 
Rich,

Yeah, I bought a Rule 2000 to do that mod with but the Rule 2000 was the wrong shape. I heard they have them round as well, need to look around and find a round one so I can do a direct swap and use the existing pumps mount.

Thanks for all the tips/ideas everyone!

Regards,
Jason
 
I agree with the grey water sump tank. Ours gets so nasty when the faucet is running and the water is pumped out, it smells as though somebody just flushed the toilet. Not a nice job but cleaning it out with a shop vac and killing all of the mold in it is a good idea.
 
I know these are old posts, I have a 460DA that I"ve always had an intermintenet oder, really bad. This weekend I noticed while cleaning the carpet, the hatch by the refrig door had an appreciable amount of water in it and the compartment behind it. I pumped the most discusting smelling water out for about 30 minutes. No leaks. The only thing I can come up with is the drain to the rear bilge pump in the aft bedroom must me clogged. There was little water in it. Since that compartment is under the washer, hot water tank etc, I think it was from an old leak...Will find out soon...Tom
 
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