Black Tank odors

[Meadows11]

First trip of the season and the camper smells are unreal from black tank... Any suggestions before the wife shows up tomorrow?

[bankr63]

Smell should not be coming into the camper at all.

First, make sure that the vent on the roof is unobstructed.

Next, make sure that ALL traps have water in them. The only trap for the toilet is the flush trap in the toilet, but the toilet should always have a bit of water in it. If the toilet doesn't hold water then you need to replace the seal on trap. Smells could also be coming from the gray tank. Most often my culprit is the shower drain as we don't generally use the shower. Pour a cup of water down there and run water into all the sink drains as well.

Final thought is to be sure that it really is a tank that smells. Mice and other rodents have a nasty habit of dying in inaccessible places, and they tend to stink for a while until fully decomposed. A dog with a penchant for rolling in smelly things might help to suss out the location.

[WyEm]

It may not be your black tank. It may be the gray tank. Since each sink does not have a vent to the roof, there is a vent under each sink with a check valve (I don't know the exact description), but sometimes it gets stuck open allowing the gray tank smell into the trailer. Just tap on the vents under each sink to jar it loose and closed and see if that works. I've experienced the stink and this worked.

I googled it and its is called an "Anti-Siphon Trap Vent Device" or "Air Admittance Valve."

[bdreinv]

Had same problem filled black tank to the max used some dawn dish soap let set for a couple hours and dumped.Lots of stuff came out.Did same process three times over about 8 hours.Would guess vent pipe was plugged in tank. See what happens Labor Day Camp out.