Black Tank Odors

[DelawareEagle]

Hi Everyone, I've learned a lot from folks in this forum and am hoping someone can give me some advice. After coming back from our recent trip and parking the camper in the driveway I noticed an odor that smelled like it was coming from the black tank. Our camper doesn't have a black tank flush so before we leave I dump it, use the whirly thing that attached to a hose down through the toilet opening. After that I fill it with fresh water until it is completely full, then dump it. I repeat this process two to three times until the water coming out of the tank as viewed through the clear coupling to the tank dump is clear. Finally I put about one to two gallons back in then use the tank deodorizer that is formaldehyde free and drive home. I've never experience this before. I crawled around under the camper and could not see any obvious leaks. I'm wondering if this could be coming from the vent pipe through the roof but if it is venting as it has in the past I wonder why I'm smelling it now. Anyone have an idea on where I can look? Thanks.

[mcfarmall]

Sounds like you keep the black tank pretty clean. How about the gray tank? Those can get stinky too.

[RVhiker]

Here's my opinion.

Tank chemicals are largely useless. The key I think is to keep your tanks relatively clean. I do this by 1) dumping only when nearly full and 2) putting several gallons back into the tank after dumping - the sloshing of the several gallons as you travel to your destination help to break up solids.

mcfarmall is entirely correct that a grey tank - especially the galley tank - can stink. Some grey tanks have vents that are interior to your trailer. If that vent malfunctions - stays open when it should be closed - your trailer can stink. These vents have a flapper valve that is supposed to open when dumping to allow air flow into the tank; the flapper is supposed to close when the dumping is done. The cure (if this is the problem) is to replace or clean the valve.

[Camper_bob]

I'm going to have to agree with the standard tank chems being useless. I use PLENTY of water when flushing, I top off the tank with fresh water before dumping, I rinse out my black tank to get it relatively clean after primary dump, then dump 5 gals of water and a drop in chem pack before leaving the park. Tank with chems sloshes all the way home, trailer goes to storage for a month or more with just fresh water and chems, then when I bring it home for the next trip, stiiiiiiiinky tank. Granted, I only smell it because I'm standing there holding the toilet valve open to rinse the antifreeze out of the bowl, but still, it's VERY stinky.

So I'm going to try the "sewer juice" method while in storage to see if that helps keep the stink down. I immediately went in the house and mixed up a couple batches, one for now (because I can't stand that smell) and one for after we dump and rinse the tank this weekend. We'll see how it smells in a few weeks when I pick it up for our next outing. Last time I used the stuff, I could only smell the Pine-Sol, and that's a pleasant smell for a black tank.

[Danmer]

Here's what I think,
If you have an exhaust fan running in the bathroom when you holding the toilet flush valve open, you will get some fumes from the tank.
Good luck.

Dan

2011 Tacoma
2013 Swift 185

[DelawareEagle]

Hi All, Thanks for the thoughts. I learned the hard way about running the exhaust fan in the bathroom when having the toilet valve open trying to clean the black tank. I figured it was a rookie mistake as we went from tents to pop-ups then the travel trailer. I had not given thought to the grey tank having the odor. I usually fill my sink with water and Dawn and then let the water run to fill the grey tank as the final dump through the sewer hose after flushing the black tank. I thought that would help not only cleaning the grey tank but having soapy water to flush out the sewer hose from the black tank flushing. The problem is the smell is "around" the camper on the outside. There is no odor inside the camper. At the moment it's in the driveway between trips and I notice it when I walk by or near it. I don't have anyplace to try and fill then dump it here. I usually do the water and ice method either going from one campground to another or on the way from home. Yeah I know we'll only fill it again but at least it will have some cleaning. I was just concerned because in the three years we had the trailer this was the first trip that I came back and after putting it to rest in the driveway I could smell the odor around the camper.

[clutch]

Grey tank usually stinks worse than the black tank.

[Camper_bob]

Originally Posted by Danmer

Here's what I think,
If you have an exhaust fan running in the bathroom when you holding the toilet flush valve open, you will get some fumes from the tank.
Good luck.

Dan

2011 Tacoma
2013 Swift 185

See, that's the thing, I didn't even have the fan on (BTDT) and I was still getting a pretty fierce stink!

[lx22f/c]

I use to have black tank odors too. When i had my roof replaced i had them install the siphon 360 on both the black and grey tanks. No more smell at all and only water in tanks. If you watch the video on their website you will know why you get the stink from different times. One place i keep my camper during dove season the winds are forced through a series of barns and every year when parked there my camper would stink bad. When i would move it back to my seasonal site no smell. The wind was creating pressure in my tanks and when we flushed the toilet it would escape to the trailer. Yuck! After the siphon 360 no problems. I hope this helps.

[Jeff61]

Buy yourself a flush-king. Fill it up a couple times. You'll see the last reminants of paper and ca-ca coming out. I havent experience a stinky terlit since! Best $50 bucks you'll spend on accessories

[amaryllis]

I experienced the same thing. I use and love the flush king, but still had the problem. It was the grey tank! Now after dumping I like to add some water (gallon or two) with Odoban or Pinesol and let the ride home clean it up. I use a 5 gallon bucket and dump the grey into the toilet at home. Haven't had a problem with smell since adding this to my routine a few times during camping season.

Good luck!

[Milehi]

Not sure if this helps but we had the same issue with our '03 Jayco with a hand flush toilet. After one season of on again off again smells, regardless of how well we cleaned the tank, i removed the toilet thinking the seal had gone bad. Turned out to be a torn/rotted rubber accordion seal that sealed the shaft that connected the hand lever to the flush valve.
Good luck!

[DelawareEagle]

Hi All,

Thanks for all the ideas and suggestions. The odor seems to have gone away from outside the camper. It is presently parked in the driveway. We are loading it up for our next long trip so I'm going to try some of the suggestions offered. Again the odor was not inside the camper but on the outside as I walked around it. I did dump some water in the black tank and will see how things go. I appreciate all the ideas.

[tnmcouple]

Someone on here told me that he adds a couple capfulls of dawn dishwashing detergent after cleaning the black tank with just enough water to cover the bottom and stores it like that. He says it takes care of the stink. I haven't tried it yet so I can't speak from personal experience.

[xkuzme1]

I flush it til it flows nice clean water. Then instead of using RV chemicals, Ive been using dollar store fabric softener. Smells better, much cheaper, and the TP dissolves better. I was thinking about some dollar store pinesol for when it sits long periods just incase.


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