1999 Brave Very Smelly - Sewage Smell???

[Tararuj]

We bought a 1999 Brave and moved in full-time in May and since we've been living in it full time it continues to get smellier and smellier. It smells like sewage to me. We have done all of the things to try to mitigate this. We have replaced the toilet, we have gotten a hose with an extender to go down inside of the black tank and hosed it fully out, we got products that are supposed to help clean out the tanks,. The gray tank smells just as bad if not worse. When we open the cabinet underneath the kitchen sink it smells like sewer. It doesn't matter if we have just emptied the tanks there is always a smell. I have tried baking soda and vinegar, products that are used for cleaning gray tanks that we've let sit overnight before rinsing the next day, we do not seem to have any sort of clog because all of the water seems to come out just fine but there does seem to be a problem and I'm just at my wits end. I'm just not sure what else to do. Can you help? Anyone else have this problem and was able to resolve it? Also, just to be clear, we are not hooked up to the Sewer because I was concerned that that was the issue so we only hook up our pipe to the Sewer when we are dumping.

 

[Eagle5]

Hi Tararuj,
The best Gray and Black holding tank additive to use is Borax. Add a ½ cup to each tank, and then prime with a few gallons of fresh water. I would not use any other treatment. Borax is the best.
Try to never let stuff stay in either tank for more than a few days. They are not septic tanks; they are holding tanks. Empty them, flush them out as best you can, then add another ½ cup of Borax in each tank with priming water.
Check your sewer vent(s) to be sure they are not obstructed.
Eagle5

 

[Tararuj]

I'll try that! I think we checked the Sewer vents but I'll check again. We dump our tanks every 3 to 4 days so I don't think that it's that we are holding stuff too long. We have a sewer hookup at our site so it's easy to empty them but we also stay near a restroom so we try to use that more often than our RV toilet. Any idea why it stinks so bad underneath my kitchen sink? I can't seem to figure out what the problem is there.

 

[Eagle5]

User Morich is very good at pulling-up plumbing diagrams, so maybe he can chime-in here. It could be some sort of under-sink venting, or perhaps a leak that is so small it is hard to detect. Can you empty-out from under the sink and lay-down paper towels to act as a leak indicator?
Eagle5

 

[Morich]

We woold need to know exactly which Brave to get drawings for the exact location of valve, but general idea may help.
Many RV have an "air admittance valve" under sinks and vanity.
You may spot one by looking along the drain line under the one that smells. It can be hiding in a small place cut into the wall or in the open? May look like a pipe starts upward but has a "lump" at the top ?

https://www.lowes.com/pd/Keeney-Plastic-Air-Admittance-Valve/1069119

These can go bad in two ways.
If it sticks shut and doesn't let air in, suction can be created when water goes down drain and this suction can pull the water out of the trap and down the drain.
this can leave the water gone from the trap and it doesn't stop smell from coming up into the room! If you smell it before you open the cabinet, that sounds right.

But if the smell is much stronger under the cabinet, the valve may be stuck OPEN.
When this valve sticks open the trap keeps smell from going into room but it can come up the pie and in under the sink!

Small way to test? If you run something like a wire down the drain tot he trap, it should come back out wet if water is staying in trap as it should! If dry, suspect the valve not opening to relieve suction as water goes further down the drain!

 

[Tararuj]

Thank you so much for your reply. I appreciate the advice. I think I found what you were talking about and have indicated that in the photo. But my pipe always has water in the p-trap. I can see it just by looking down my drain which I've also indicated in a photo. It stinks all of the time but it does seem to get worse after we use the sink to wash dishes for a day or two. It smells the second you walk in the door but it's definitely worse when I open up the cabinet doors underneath the sink.

 

[Morich]

Good deal! Always nice to be able to look and get a better idea of what you have.
But that still can leave some question, so I might make a couple suggestions and let you decide which fits you best?
Our noses are not really good at pointing us to exactly where and what we are smelling. Grey water, even when it is only soap, etc will leave a pretty bad smell and I've never got a holding tank to what I call clean! So they smell but there "should" be a vent and if all is working rightmost of the smell goes up the vent to the roof and out. This is because the trap should have water to block smell from coming up through the sink drain and into the room as one and then when we are not draining any water the flap inside the valve should flap back into place to seal the smell coming up backward through that valve and under the sink.
Idea is that both routes from the tank to inside are blocked if all is working well! That means most all smell finds it easier to go up and out the vent to the roof.
But there always seems something that might" mess with our mind!

There should be a vent somewhat inline over this sink on the roof! They can have some bends but normally go pretty well straight up and out. They should be something like a 1 1/2" to 2" pipe with a cap on top.
They can get stopped up if you have a really dedicated bug of some sort that doesn't mind the smell!
Mud daubers or wasps that build a paper nest can actually build them tight enough and large enough to nearly fully stop up the pipe! If you can get a good look at that top cap, it might be possible to spot a nest that they built all around just under that cap to hold most of the air in?
Does it look like anything sticking out if you look from the ground?
Or? It might be okay to go for a new valve inside as they tend to be not too pricey but maybe a pain to get to where it looks like you found yours!
They often need something kind of big like large slip joint pliers, etc. to get a good grip to unscrew it. Hard to say how stuck it may be, though!
Changing it to see if the smell goes away might be a handy way to get relief?
But a different way may fit? If it is stuck open and letting smell in, one way to test is to put something like plastic wrap or a baggie over the valve, sealed down tight to keep smell from getting up and into the room?
When you do this, there may be more chance the water gets sucked out of the trap, so be aware that you need to add enough water after draining a while basin! This sucking the water out of the trap is all kind of different, depending on how far the pipe runs and how much water goes out to much the suction!
I see no real good ways to go until you find which of several things "might " be true!!
I've seen a lot of really weird stuff on RV and some of my guesses are based on what I've seen.
But that leaves a whole bunch of stuff that I'm wrong about, too!
My wife tells me I can be as ignorant as the best of them!

 

[Morich]

I've had my dinner and part of it made me think of a different idea that may depend on how well trained your nose may be??
I had some wild caught smoked salmon and that IS NOT a fav with me!

But it made me wonder what the odds of the smell being something different than the tank smell? Any chance of it being a mouse died under the base of the sink cabinet?
I'm not real good at sorting me of that sort but thought to mention that there are often boards that are just laid pretty loose in the bottom of some cabinets and you might check that idea before going too far on others?

 

[Tararuj]

First, I can't thank you enough for taking this much time and effort to help me resolve this issue. I will have to check the vent on the roof tomorrow because it's already dark here but that's a real possibility. If that's not it I will try the Saran Wrap thing. We did have mice in here recently and put out poison but the smell was a problem prior to the mice. Although, mice are another problem that I am struggling with but I'll address that later. The other thing that makes me believe that it is the tank/pipes is that it seems to get stronger when we have any sort of Wastewater in the tank and then is not as strong right after I empty it.

 

[Morich]

A suggestion to try if it is easy enough to make it practical?
If the vent cap is that type that pulls off, maybe sticking a hose in and letting some water run down the pipe will let you know it is open or if there is a wasp or mud dauber in it, the water might make it fall apart and go on down into the tank! Not to put so much water in too fast in case it might flood something inside but the water should just follow the pipe straight on down and not come out inside.
But I never trust that sort of thing too far!
Weird idea to check if it is tank smell or something else? If you pour a cup or so of bleach down the drain, it makes a pretty strong smell that is lots different than dead stuff.
Maybe you can get an idea if the bleach smell comes up strong, then you could say the smell is from the tank?
If you pour beach in and then plug up the drain in the sink, would that let you know the smell is coming out of a stuck valve?

Yes, You are right. I'm just throwing out ideas to think over and maybe one tells you something! Good luck on the search!

As far as my time, I am often stuck here waiting for guys to call after they check some of my ideas on what might be wrong. Here in Austin, we are a bit East of a working oil field area (Permian Basin) and they have several guys who are great at tearing things apart and fixing them but they are not always the best at reading electrical drawings and the fussy stuff about finding problems.
So it's kind of like what we do here on the forum? They call me and ask something like "where does this wire go" and I try to figure out an answer while they drive 10-100 miles out in the bushes! So I spend a lot of time doing nothing but I get paid really well for waiting!

 

[RV_Lee]

Does it have a poop pyramid in the black tank?

 

[Old Navy]

A long shot, but you don’t have a Dometic 300 toilet?

 

[Tararuj]

I do! I just bought it!

 

[Tararuj]

Does it have a poop pyramid in the black tank?

I really don't think so. We got one of those hose extenders that you used to clean the black tank out and we've done that three times. There does not seem to be anything in there

 

[Old Navy]

I do! I just bought it!

There was a defect in Dometic 300s that caused urine to collect in a void inside the toilet. Google “Dometic 300 toilet smell” and you will find plenty of information on the issue. Replacement is an easy job. You can pull the toilet and flush it out the smell for quick fix, but replacing it is the best option.

 

[Tararuj]

A suggestion to try if it is easy enough to make it practical?
If the vent cap is that type that pulls off, maybe sticking a hose in and letting some water run down the pipe will let you know it is open or if there is a wasp or mud dauber in it, the water might make it fall apart and go on down into the tank! Not to put so much water in too fast in case it might flood something inside but the water should just follow the pipe straight on down and not come out inside.
But I never trust that sort of thing too far!
Weird idea to check if it is tank smell or something else? If you pour a cup or so of bleach down the drain, it makes a pretty strong smell that is lots different than dead stuff.
Maybe you can get an idea if the bleach smell comes up strong, then you could say the smell is from the tank?
If you pour beach in and then plug up the drain in the sink, would that let you know the smell is coming out of a stuck valve?

Yes, You are right. I'm just throwing out ideas to think over and maybe one tells you something! Good luck on the search!

As far as my time, I am often stuck here waiting for guys to call after they check some of my ideas on what might be wrong. Here in Austin, we are a bit East of a working oil field area (Permian Basin) and they have several guys who are great at tearing things apart and fixing them but they are not always the best at reading electrical drawings and the fussy stuff about finding problems.
So it's kind of like what we do here on the forum? They call me and ask something like "where does this wire go" and I try to figure out an answer while they drive 10-100 miles out in the bushes! So I spend a lot of time doing nothing but I get paid really well for waiting!

We finally got a chance to get up on the roof and check out the ventilation situation. There is not a cap on the vent above the bathroom. I provided a photo. I also provided a photo of the inside of the pipe with a light. It's hard to see anything but it kind of looks like there might be something obstructing the pipe. There is not a ventilation pipe above the kitchen sink area. I've provided a photo of that area as well.

 

[Morich]

I see one thing that may be part of the problem as the cap on top is missing!
That may mean something got stuck down in the vent pipe? Leaves, insect nests, or if there is really bad news, somebody may have dropped something down the pipe!
People do weird things to mess with the rest of us!

I had a friend who had rental property where the folks had parties out on the roof where a larger vent came up. Suddenly they had plumbing trouble and he finally found somebody had dropped a beer bottle down the vent to stop it!
We'll hope you are not that bad!

But better to add a cap when it comes handy!

Two vent pipes are often combined to use one opening on the roof for two or more vents!
For drawings of your specific RV plumbing, go here and sort to correct RV:

Plumbing Diagrams

Something like this one? Probably not the exact same RV as you have as I did not find info on which model 99 Brave you have.

You may only see the connection for the joint of the two pipes? Or you might be able to see something stopping air coming out of the pipe?
A semi-easy way to learn more might be to try running a garden hose down the pipe? Be aware that it may be a wasp nest, so maybe start the hose end in just a little and stand back before turning some water on. Wasps tend to get even when they find who is messing with them!
But the water should just run down the pie and into the holding tanks, either the black or the grey waste tanks, depending on how the pipes may be built. It should flow easily down from the roof to the tank but I never like to run too much water until I find for sure where it is going! Start slow and make sure it is not coming out in the bed before running a lot?
If you are some place where a little water run on the ground is not a problem, maybe open both black and grey waste tank drains and pour a gallon jug of water first?
If you see water actually comes out the drain, then go for lots more or run the hose down to sort of "feel" if it is going all the way to the tank?
The end may try to hang up on joints of fittings but if you wiggle/turn the hose, it should go on down near eight feet or so!

When I swap RV, I always wonder what I might find!
So far it has been dirty underwear but never a pot of gold!!

Good luck on the chase!
Maybe a squirrel found a neat place to hide his acorns??

 

[Tararuj]

Again, thank you so much for your help! Tomorrow we will run a hose down and see what happens. So your assessment is that the sink in the kitchen and the sink and toilet in the bathroom all run through the same vent? Or am I missing a vent for the kitchen sink?

 

[dkoldman]

I don't know anything about a 1999 Brave, but from a few things I have read, a few things I would try or do.

#1 Drain and flush all tanks
#2 Verify the vents are not clogged. Take a hose with low pressure and let it flow down from the roof to see if it backs up or come out the main drain. Hopeful both will do fine and you get no water seeping on the floor or walls, that is why you do with low pressure. if you d see water draining anywhere but main drains, you have found your problem
#3 Assuming vents are fine, I would the Siphon 360 vents to replace both on the roof. They can help vent with just the slightest of wind.
#4 At this point, I would reverse engineer. Starting with Gary tank, I and after a few rinses I would fill with water being careful not to overflow, verify no leaks, then add a gallon or two of the freshest good smelling laundry detergent you can find, the goal is make it so strong that you can smell it from the sink drains. If the smell goes away you know it is related to gray tank, if you still smell to to #4
#5 Repeat #4 with black tank, at this point your RV should have nothing but strong fresh smell, lets assume it is fresh and bad smell is gone.
#6 Drain gray tank and only use the water that goes to the gray tank, accelerate to fill the tank with normal like usage to see if smell comes back, if not try the same thing with black tank.

I hope this will help you to find it, because I think one of the tanks or seals are broken. You just have to narrow it down.

 

[Morich]

So far I have only been showing random info on vents as I don't know exactly which floorplan you have. Which floorplan RV do you have? With that info we can pull up the correct drawings and see where the lines and vents were placed.
There should be a label somewhere near the driver's left side with lots of info you may need to find exactly which you have if you need to have part for the chassis or some RV coach parts.
One thing that can confuse is when Winnebago buys what they call a stripped chassis from a company like Ford, it may be a 1999 and then by the time Winnebago builds the top on the chassis, it may be 2000 and that means you may have a 2000 RV but to get something like brake or engine parts, you may need to buy them for a 1999!
Item 13 is the one we need to find the drawings for this RV:

For more complete info on this label, this is the owners manual for your RV and it has lots of other info that may help you find small things like drains and electrical things:

https://www.winnebago.com/Files/Files/Winnebago/Resources/OperatorManuals/Operator1999/99Brave.pdf