Black tank fumes

[fltrker]

Partially emptied the black tank as the receiving facility was full.
Buttoned up the line and closed all valves and drove 1/2 mile and black tank fumes started coming into the m/h maybe around the washing machine area. ?
When we Stopped the smell stopped. But as soon as we moved the next day. They came back.
What is the problem?
Where could it be coming from and how to fix it.
Stinky.

[fltrker]

It was the washer trap.
Thanks

[doxiemom11]

We had that once. The grey tank vent pipe had come apart and slid down into the tank further which was letting the "smell" out below the roof inside the coach, rather than above the roof outside. DH pulled vent tube up and reconnected everything in the correct position and that stopped it.

[BarbaraOK]

Get a rotating roof vent for both black and grey tanks. Will increase air flow over the vents and thus pull odors out and away as you are moving. Also, check the fitting of the drain hose into the drain line - - had to rewrap ours as there was just enough movement to let air/odors escape.

Barb

[MCDDY]

We've had that happen a couple of times. Stagnant gray water stinks like sulphur and will smell up your coach pretty quick. As a precaution just set the washer on a rinse cycle and turn it on, this will fill the P-trap.
Dave

[ArchHoagland]

We close all three of our roof vents when we are moving.

We've had problems when they were open causing a vacuum and drawing black tank smells into the coach.

So try closing all vents and windows to see if that affects the problem.

[sssooo]

it is your washer that is causing the smell,just run a cycle with the machine to get some water in the trap

[crasster]

That's when you pull the "dirty bandito". Open the valve and continue down the road. j/k 🙂

[HappyKayakers]

fltrker wrote:
Partially emptied the black tank as the receiving facility was full.

I wouldn't care how long the line was. I'm sure they would understand an extra 2 minutes to completely empty the black tank.

Having said that, I'd be very careful the next time you pull that sewer cap off. Even though you closed all the valves, you may have closed the black valve on a wad of TP so it didn't close completely and is leaking black water into your sewer line.

[fltrker]

Thanks. The only possible trap w no water could be the washer/dryer. We were not able to turn it on for some reason so unable to restore water to that trap , if it has one.
It only smells when moving. We thought the toilet vent was reentering the coach by way of the roof vent but NOT the case.

[Executive45]

Sometimes you'll get smells back into the coach if you're "P" traps are not full of water and other times just because of the movement of air around the toilet vent. If you determine it is, in fact, odors coming from the roof vent, you could install one of the Cyclone Vent covers that prevent the odors from reentering the coach. Below is a link to these covers, on sale at Camping World.....Dennis

Cyclone Vent Covers

[cpmath]

What do you mean the receiving facility was full? Huh? Once you start to dump you don't stop until your finished dumping. How did you stop dumping?

[fcooper]

May not be the blank tank. I suspect you're smelling the gray tank which can be as bad as the black tank. Be sure all of the traps have water in them ....including the washer drain. If this does not help, then start replacing the air admittance valves under the sinks ($5.00 approx at Home Depot).

I don't have a washer, so I've taped over the drain line so I don't have to worry about the trap losing water.

Also be sure you don't have a stove burner slightly turned on as propane can smell bad also.

Outgassing on a bad battery can be bad also.

Good luck.

Fred