STINKY PROBLEM 2003 Seabreeze LX 8341

[Kliwks]

I have a stinky problem. When I am camping, I get no odors at all from my black tank. However, when I start driving, I get really bad black tank odors inside the motorhome. It doesn’t always happen, but frequently does. It doesn’t seem constant. It will diminish or go away sometime and then come back. I have tried closing all the rooftop vents and leaving the windows closed. That seemed to help a little. I am not sure how the smell gets in. If you stop an open the bathroom door, there is no smell in there, so I don’t think it comes from the toilet. (New seal in toilet,and the mounting flange). I am thinking there must be a partially disconnected vent pipe or something. Has anyone ever had this problem? I have had the motorhome for 4 years and has always had this problem.
Wondering if anyone has a diagram of the black tank venting system. (i.e. routing and access). I have plumbing schematics but no venting.
2003 Seabreeze LX 8341

[pops2]

Had the same problem in a Tradewind stated using Aqua-chem in both the black and gray water tanks and that poop sell has not bothered us since.

[Rorytug]

I had the exact same issue. It ended up being my grey tank. When traveling the water empties from the shower P trap and allows the gases up into the coach. I now fill a small sandwich bag with water and place it over the drain in the shower while traveling in order to stop the orders. Once parked, The P traps are filled and that blocks the orders. I also treat my grey tank on occasion to help. An aquachem pod and 5 gallons of water for the final drive home.

[Kliwks]

I will try blocking the shower drain, but I don't remember the smell being strong in the shower. But I will try anything. Its gross.....
Do you guys use the same treatment for the black water tank in the grey?
I know Thetofrd makes something specific for grey tanks.

[legryz]

I had a similar problem on the 2008 Dolphin we purchased recently.
One of my problems was the toilet seal, wasn't holding water, replaced the seal.
The second problem was in the vent chase. I guess when they put the vent into the tank they only use a expanding foam sealant (can type) that wasn't done too well, I dug out most of the old stuff and resealed the area.
The third I found while fixing the second problem. The hole in the roof that they cut for the vent to exit wasn't sealed. The outside cap to the roof was sealed but the hole in the roof around the vent was open possibly allowing for the fumes to enter the area above the ceiling. Not sure if all the Nationals were done like this or just the last few when they knew they were closing.
Here's a picture of the much oversized hole that I found, that was not sealed. That's the way I found it.

[Coloradodude]

I have had the problem before in my old motor-home at times..Smell can come from bathroom sink or kitchen sink. Water evaporates/drains on hilly roads from P trap. We keep sinks plugged or full of water. Something u might try.

[Scooter]

Do you have ABS fittings for a washing machine ? If the washer is not installed, the capped end of the ABS may be faulty, letting gray water tank odors into coach.

[Akcontender]

I had problems with my old RV especially when I was driving down the road and I would crack open a window. It was the suction bringing fumes back into the coach. I purchased a device that I can't recall the name of from an RV parts store. It cost around $28 as I remember it and it installs on the roof vent. It senses the wind direction either from you driving or just the ambient breeze and causes the suction to go from the tank to the rood the way it was intended to go. Sorry I forgot the name of the device but it is easily found and not difficult to install at all.

[Kliwks]

Thanks Scooter, but no washer hook ups.
Akcontender, I do have one of those vents. Not sure of the name either.
I did pick up some grey water treatment yesterday. I'll give that a try, and plug the drains.
Last trip coming up this weekend, and I will be dumping at the CG before I leave, so I may not know the answer until next season.

Thank you for the replies.

[okcnewbie]

We installed these this past week. For them to work properly you need wind so on still days you may get some smell. When moving they work perfectly. On windy days I can hold open toilet flapper and still not smell the black water tank.

http://www.amazon.com/360-Siphon-RV-...60+siphon+vent

[brabono]

I have no odor when parked, but smell is terrible when moving. I have those moving whatyoucall it's on both. vents. Use twice as much Happy Camper. Still smell. Checked vents not plugged.

[BEACH]

The problem could also be a bad vacuum breaker under the sink... the one under our Tradewinds galley sink failed and in awful grey tank odor

[Coloradodude]

I have the 2004 8341 SeaBreeze. We just came back from a trip. No smell what so ever. But my wife always plugs the sink drains and fills with a little water.

Might be worth a try.

[Kliwks]

Thanks Coloradodude. I will definitely try that tip next year. Getting ready to put the MH away for the winter. I hope it works.