Black Water backing up in shower when driving.

[BKLaw]

We do a lot of camping where there are not any dump stations. We usually dump when we get back home, but this last time sewer had backed up into shower and bathroom sink. It was a rather smelly cleanup. Any ideas on why or how to prevent this from happening again?

[pjay9]

Show us some pictures of the issue!! Just saying!

[BKLaw]

ticki2 wrote:
I'm not sure of the Six Pac set up but most RV toilets are connected directly to the tank with the toilet flange . IF yours is like that you can remove the toilet and have a 4"access hole in the top of the tank.

Good point.... I have a call into Fourwheel campers to ask if they have any or what kind of support under the tank.

[ticki2]

I'm not sure of the Six Pac set up but most RV toilets are connected directly to the tank with the toilet flange . IF yours is like that you can remove the toilet and have a 4"access hole in the top of the tank.

[Bumpyroad]

jamming a pipe in will put quite a strain on the bottom of the tank in a small area.
bumpy

[BKLaw]

BKLaw wrote:

Joe417 wrote:
I bought 1/2" x 1/2" aluminum "U" channel from Lowe's and attached it across the top of the tank with SS screws. The only weight it has to hold is that of the tank.

So far so good, 3 years now with full tank capacity, but haven't used the 5thW
too much, maybe 4 weeks total. We have been using the TC a lot more.

Top of the tank would be VERY hard to get to on my truck camper. Im thinking of cutting a piece of PVC pipe 5" tall and as big around as the clean out hole and see if I can't use that to push the top up again. Unless someone has better idea. Only good access to tank is thru the clean out.

[BKLaw]

Joe417 wrote:
I bought 1/2" x 1/2" aluminum "U" channel from Lowe's and attached it across the top of the tank with SS screws. The only weight it has to hold is that of the tank.

So far so good, 3 years now with full tank capacity, but haven't used the 5thW
too much, maybe 4 weeks total. We have been using the TC a lot more.

Top of the tank would be VERY hard to get to on my truck camper. Im thinking of cutting a piece of PVC pipe 5" tall and see if I can't use that to push the top up again. Unless someone has better idea. Only good access to tank is thru the clean out.

[Joe417]

I bought 1/2" x 1/2" aluminum "U" channel from Lowe's and attached it across the top of the tank with SS screws. The only weight it has to hold is that of the tank.

So far so good, 3 years now with full tank capacity, but haven't used the 5thW
too much, maybe 4 weeks total. We have been using the TC a lot more.

[MiPaJacks]

Sometime I think grey water stinks worse than black, at least you expect black to stink!

[BKLaw]

After getting back this weekend I think I found the problem. Top of black water tank is sagging about 1/2 way, causing tank to only partially fill. The vent tube is in the center of the tank, so it is lowest point on the top of the tank. Any ideas on a fix beside replacing tank, like some type of spacer or center support? I need some way to push the top/ceiling of the tank back to original heigth.....

[Terrick_down_Un]

( Are you talking about a P-trap, or an actual valve that you can turn on and off? )

It is a swinging rubber flap that is supposed to let the shower water out and into the tank, but when any water tries to flow back the wrong way is swings shut and stops the flow. Here is one from amazon

http://www.amazon.com/Zoeller-30-0181-Check-Valve-Inch/dp/B0009WD1L4/ref=sr_1_fkmr2_2?ie=UTF8&qid=1436481045&sr=8-2-fkmr2&keywords=swing+check+valve+horizontal+PVC

they have it pictured in the vertical position but ours is horizontal.
Hope this helps.

[Deb_and_Ed_M]

BKLaw wrote:

Deb and Ed M wrote:
Just a thought: was the ceiling vent open? I wonder if a slightly-open vent created a suction in the bathroom as you went down the road?? Might explain how the sink could have black fluid, without having the whole bathroom afloat in it? Or maybe the vent stack is creating pressure in the tank?

I know in our previous Class C, having the skylight vents open on the roof created enough suction, that black-tank odors were drawn into the RV unless we created equal pressure by turning on the dashboard air or opening a window. At least on a Class C, the tanks are farther below the bathroom fixtures (plus we seldom boondocked. The tank was usually empty when we traveled)

Yes it was, the one in the bathroom.... That might have had something to do with it.

It was explained to me, that the curved top of an open vent creates aerodynamic suction/lift; and apparently quite a bit of it! If the bathroom door was closed (surely it was while on the road) - then there's no way for air to get into the bathroom to balance out that vacuum, so in the case of a Class C, the air comes from the black/gray tank vent, back up through the drain pipes, into the room. Of course in a TC, the tank is much closer to the fixtures, so you actually got liquid.

Keep the vent closed, and see if it happens again on your next trip??

[BKLaw]

Terrick down Under wrote:
Hey, we had a similar problem just after we had bought our TC. When I opened up the lower space next to the shower I found a non return valve just around the corner, about 8 inches from the shower drain and not easy to get at. When I finally got it out I found all sorts of junk stopping the valve from shutting off. Put it back all clean and have not had a problem since.
Hope this helps.

Are you talking about a P-trap, or an actual valve that you can turn on and off?

[BKLaw]

Deb and Ed M wrote:
Just a thought: was the ceiling vent open? I wonder if a slightly-open vent created a suction in the bathroom as you went down the road?? Might explain how the sink could have black fluid, without having the whole bathroom afloat in it? Or maybe the vent stack is creating pressure in the tank?

I know in our previous Class C, having the skylight vents open on the roof created enough suction, that black-tank odors were drawn into the RV unless we created equal pressure by turning on the dashboard air or opening a window. At least on a Class C, the tanks are farther below the bathroom fixtures (plus we seldom boondocked. The tank was usually empty when we traveled)

Yes it was, the one in the bathroom.... That might have had something to do with it.

[Deb_and_Ed_M]

Just a thought: was the ceiling vent open? I wonder if a slightly-open vent created a suction in the bathroom as you went down the road?? Might explain how the sink could have black fluid, without having the whole bathroom afloat in it? Or maybe the vent stack is creating pressure in the tank?

I know in our previous Class C, having the skylight vents open on the roof created enough suction, that black-tank odors were drawn into the RV unless we created equal pressure by turning on the dashboard air or opening a window. At least on a Class C, the tanks are farther below the bathroom fixtures (plus we seldom boondocked. The tank was usually empty when we traveled)