Is it typical for the trailer to smell like **** after it’s towed?

[cantdrv55]

It doesn’t smell lie that when it’s parked but as soon as it’s moved, it starts to smell.

[Foiled Again]

Sounds like your black tank has not been thoroughly cleaned and/or you have a bad seal in the toilet bowl and/or ypur black tank vent pipe is clogged.
The tank rinsers aren't all that great, and it is good practice to finish dumping the tank, and periodically put 5 to 10 gallons of clean water into the tank thru the toilet bowl, add a bit of bleach, and let it slosh around while you tow the trailer, then flush and rinse again. If that results in your trailer reeking of bleach, replace the bowl seal. A drain snake dropped down the vent pipe will clear mud dauber nests, etc. Of course, precede that with wasp spray of you see any of the little buggers.
None of that effective? Time to look under the toilet for a floor problem and around the tank for a hole or crack.

[OTRA15]

Good advice. Also the black tank’s vent stack may have separated from the tank. Raw sewage contents would eventually fall over the edge of the tank, drip onto the underbelly skin, and eventually leak out onto the ground. Best to diagnose this sooner rather than later!



What age and model is your trailer?

Good luck,

Peter

[Bill M.]

No, that smell after towing is not normal. As mentioned, there is a problem with the sealing of the black tank somehow. The toilet to tank seal would be the place to start looking. Different trailers are connected in different ways. Does the toilet still hold water after traveling? And the black tank vent connections should be checked. And under the trailer for a leak. But somewhere you have a leak from the black tank. Or possibly the gray tank, though the smell is different.

[Mollysdad]

Do you drive with any roof vents open? The black tank vent pipe can be very nasty. If not, then I'd start looking for leaks.
BTW, I'll assume you use a chemical in the tank? Mine doesn't smell bad usually.
If you're using some "all natural, organic, enzymes, made from Unicorn flatulence." type additive, I think I'd go back to "Man, I need a Hazmat suit to handle this!", additive.

[Al and Missy]

If you have a black tank flush there probably is a vacuum breaker in line. Mine is under the bathroom sink cabinet. I never had the smell but my tank flush didn’t work. When I changed my dump valves I cleaned the tank flush spray head and the smell started. It is also apparent when running the fantastic vents in OUT mode.

My theory (suggested by others with the problem) is that towing creates a vacuum around the trailer enough to draw air in through the black tank vent and out through the vacuum breaker inside resulting in a smelly interior. I plan to replace the vacuum breaker with an elbow and use an external one if I flush.

Al

[ghaynes755]

It might not be the black tank. Depending on the trailer it could be a bad air admittance valve or HEPVO valve on the grey tank plumbing side. The smell will be just as bad. Look at the plumbing page of your particular trailers parts book to see which you have and the location in your trailer.

[OTRA15]

Originally Posted by cantdrv55

It doesn’t smell lie that when it’s parked but as soon as it’s moved, it starts to smell.

Good advice so far IMO.

What model/length and age is your Airstream?

Thanks,

Peter

[uncle_bob]

Hi

Without knowing a lot about the specific trailer, guessing what might be wrong will head down *many* different rabbit holes.

Some trailers have a bathroom sink that dumps into the black tank. In that case a sink issue (like a bad drain valve) will create "interesting" smells in the trailer.

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One other (as yet unmentioned) possibility is .... errr ... dead mice. Depending on where the remains lie, the wondrous smell may only drive into the trailer when towing ...

Bob