Black tank smell in coach

[What_s_Next_]

I have had our coach for 7 years now and every once in a while while driving I get a really bad smell coming into the coach. It smells like the black tank is venting into the coach. The weird thing is it doest smell bad in the bathroom. I always flush out the tanks really well and add chemicals to the black and gray tanks. Any help is appreciated.

[dougrainer]

Shot-N-Az wrote:

dougrainer wrote:
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subtroll wrote:
We put up with a similar problem for years... bad smell while driving with a partially filled Black tank. Installing a rotating wind vane device on the roof solved our problem completely.

Your problem is still there. Installing those roof top venturi's just goes around the problem. Doug
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What problem would that be?

A holding tank vent problem. Either the mechanical vents are bad or the piping has an open in it. The point I was trying to make is, the roof top Venturi vents are a work around. A CORRECTLY functioning holding tank vent system will never allow odors inside the RV. We FIX the problem. We have NEVER installed Venturi vents to "fix" an odor problem. We ALWAYS find and fix the problem. Doug

PS, 99% of the time, it is a GRAY odor, not a Black Tank odor. Gray tanks usually smell worse than Black tanks.

[Shot-N-Az]

dougrainer wrote:
+

subtroll wrote:
We put up with a similar problem for years... bad smell while driving with a partially filled Black tank. Installing a rotating wind vane device on the roof solved our problem completely.

Your problem is still there. Installing those roof top venturi's just goes around the problem. Doug
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What problem would that be?

[Scars]

Darn, sorry it didn't fix the problem. The only internal opening left would be the shower drain so maybe cover it up with a cup and a towel to hold it in place while you drive to get the roof vent...

[dougrainer]

+

subtroll wrote:
We put up with a similar problem for years... bad smell while driving with a partially filled Black tank. Installing a rotating wind vane device on the roof solved our problem completely.

Your problem is still there. Installing those roof top venturi's just goes around the problem. Doug
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[subtroll]

We put up with a similar problem for years... bad smell while driving with a partially filled Black tank. Installing a rotating wind vane device on the roof solved our problem completely.

[What_s_Next_]

Ok so I replaced all the sink vents, there were 3 of them and I ran the washer and dryer. Leaving Friday for a weekend trip I will let you know how it goes.

[rockhillmanor]

I have never done anything to my grey water tank in any motorhome. Do you folks treat it or flush it. I would be interested in the maintenance you do do to grey tank. I flushed my black tank frequently and have done all the the things like calgon and ice cubes etc...

Calgon is a water softener. and Ice cubes do not work. Think about just how many 5 lb bags of cubes you would have to put in there to accommodate the expanse of the width of a gray tank for it to even attempt to fill the bottom to do any good.!!:W

All depends what you allow to go down your RV kitchen sink on how bad a gray tank can smell. If you put grease down the drain and lots of food stuffs it sticks to the walls and goes rancid.

If you have every parked where they allow dumping of gray water?
1. you'd know first hand just how BAD it smells
2. You'd be on the band wagon of banning dumping RV gray water anywhere.

I pick up a quart of generic lemon cleaner. I dump the gray and add the quart of lemon cleaner, fill with water and dump again. 'everytime' I dump. Cleaner takes any grease/particles off the tank walls and keeps the tank clean and odor free.

[AikenRacer]

We had the same problem and found out that the clothes washer is located in the rear near the engine compartment. Either the heat from the engine will evaporate out the p trap or the p trap is not installed right and it sloshes out going down the road. We always run the washer through a quick cycle once we park and level at the campsite. No other problems.

[outofplace]

What's Next? wrote:
Thanks for all the reply's! I'm going to try the washer dryer first since its the easiest place to start. Then I will try the traps under the sinks. I will keep you all updated. Also yes, the coach had been sitting for a while. We mainly use it during the winter months, we like to go dry camping.

We had this issue and it ended up being the W/D trap dried up.

[RayChez]

Rockhillmanor hit the nail on the head. If your coach has sat for an extended time and the water on the traps is gone, there is nothing to block the smell from either tank. Before hitting the road just run a some water on kitchen, vanity sinks, washer and run some water on the toilet. You will not have that problem anymore.

[What_s_Next_]

Thanks for all the reply's! I'm going to try the washer dryer first since its the easiest place to start. Then I will try the traps under the sinks. I will keep you all updated. Also yes, the coach had been sitting for a while. We mainly use it during the winter months, we like to go dry camping.

[Scars]

We had the same problem and the air admittance vent under the kitchen sink was the culprit. Went to home depot and replaced it and the one under the bathroom sink and no more "Who farted?" looks from the wife:B

[dahkota]

I was driving through Ohio and had a really bad smell coming in. At first I thought it was the area, but it lasted too long - well over an hour. Then I thought there might be some thing on my shoes but that turned out wrong. What was happening was I was about a half mile behind a hog truck.

[Goldencrazy]

I have never done anything to my grey water tank in any motorhome. Do you folks treat it or flush it. I would be interested in the maintenance you do do to grey tank. I flushed my black tank frequently and have done all the the things like calgon and ice cubes etc. I now have an external flush valve which is nice.

[10forty2]

Like already posted, I'd bet on a combination of the vent pipe pushing air back into the tank and into the coach as well as dry sink/drain traps. Even if your traps aren't dry when you start out, the sloshing on going down the road can cause what little water is in the trap to drain out and leave a clear shot from the holding tank into the coach. Remedy? Make sure your tanks are really clean and flushed with copious amounts of water. And add in RV tank enzymes in the black tanks to digest all the waste so it flushes out good. Seems to work really well for mine. When we first got our coach, we smelled the sewer when going down the road. After a thorough cleaning/flushing of the tanks and putting a bottle of the enzymes in after each dump, we have had no more problems.