Sewage & gray water accumulating in outlet pathway

[boyscout]

After dumping our 2018 Solitude retains quite a bit of sewage and gray water in the outlet pathway AFTER the valves for each tank. After we dump, flush, and drain thoroughly and then move to a new site, there's always an unpleasant mess waiting at the dump outlet cap of sewage/gray water that didn't drain out after the valves were closed.

I've tried raising and lowering the front of the trailer with its hydraulic jacks to drain as thoroughly as possible AFTER closing the valves, and a little more sewage comes out, but the outlet system still retains a half-gallon or more of mess to greet me at the next site.

What can be done to address this problem?

[Steve7]

Hi Boyscout,

It sounds like there has to be a low spot somewhere in your outlet pipe, unless you are not level, leaning toward the opposite side.

You can stop the liquid from coming out when you open the cap by purchasing a Valterra twist on valve to connect to the end of your waste pipe. That way you don’t release the valve until your sewer line is all hooked up. Many use this devise.

[Gyrogearloose]

Installed one of these yesterday after dumping the 1/2 gallon of buildup.

[TucsonJim]

I use the twist on valve that Steve mentioned above. It works well 100% of the time.

Jim

[JCR GD]

I added the glue on version of the above. No more problems.

[bertschb]

I don't think I've heard of anybody that hasn't encountered this problem with any RV. The easiest "solution" is the Valterra gate valve as mentioned above.

[vonzoog]

Buy one and be done with the problem. 100%. It works.

[boyscout]

I don't think I've heard of anybody that hasn't encountered this problem with any RV. The easiest "solution" is the Valterra gate valve as mentioned above.

Well for one, our 2018 Reflection did not do this.

[bertschb]

Well for one, our 2018 Reflection did not do this.

You are very lucky - and the first I've read of that has an RV that doesn't have fluid leak out when the sewer pipe cap is removed.

[Superduty]

My 18 Reflection 303 valves either leaks, or the discharge pipe has a low spot which is really what I think, as Steve7 said above.
So, in thinking about this.
Yesterday I made sure all 3 tanks were empty. Opened the drains for 30 minutes, until no dripping. Shut the valves.
I put 8 gallons of water in the black tank, with a bottle of the Blue Tank Oder Stuff.
Before I leave this Thursday, I will pull the discharge cap and see if anything comes out. (if it’s Blue water, bad black valve).
Once I get set up at the RV Part Thursday evening, I will see what comes out when removing the cap hooking up the sewer.
I hope to see no blue water. If I have clear, or cloudy water, then it has to be the discharge pipe with a low spot.
Thought this would be easy Test.
I’m not too concerned on the gray water leaking, just the black water.

[Cate&Rob]

All the tanks have about 1/2" to 1" of liquid in the bottom that won't come out past the lower flange of the gate valve when sitting more-or-less level. Before I replaced my gate valves, I tipped the trailer as high as I could in the front (blocks and fully extended landing gear) to empty the bathroom gray and the black tanks. Then as low as I could in the front to empty the kitchen gray. Probably got 5 gallons of liquid that would still be in the tanks when sitting level. So . . . if your gate valves are not closing fully (a very common problem), even if your drain everything completely "dry" sitting level and stationary, the sloshing while towing will transfer some of this last 1/2" of liquid in what you think is an "empty" tank, into the drain manifold.

Rob

[Superduty]

Rob,
Your discharge pipe. Did you notice during your valve replacement, if it was level or a slight downward angle for drainage?
I might be getting 1/2 gallon of water after traveling, so I wonder is it a low spot on the pipe? I have not gotten any solids so far.

[Cate&Rob]

Hi Steve,

The crosswise manifold collecting the output of the three tanks, is very close to "level". A couple of inches difference in road elevation side-to-side could make the difference between draining the manifold pipe completely or leaving some liquid in the curb side end of the manifold. From your description, I would guess that you have a leaking gray gate valve that allows some "travel slosh" out into the manifold, but your black gate is sealing completely.

When camping, with a twist on gate valve on the output connection, do you gather a full drain manifold of gray water with all three gate valves "closed"? This would confirm a leaking gray gate valve.

Rob

[Superduty]

Rob,
I will have to invest in a gate valve. Never know when I might need one or another camper. I will test this out while on vacation starting this Thursday. I will keep the gray valves close and see if I collect water in the pipe, after I get the gate valve.

As always, good talking with you, Steve

[boyscout]

You are very lucky - and the first I've read of that has an RV that doesn't have fluid leak out when the sewer pipe cap is removed.

To be clear we're not experiencing a dribble or a cup, we're getting a half-gallon or more, sometimes with chunks in it. This after closing the valves, tipping the trailer up and down, and waiting until no dripping when the dump hose is removed. The dozen or so people we've talked to about it during our travels - a few in Grand Design trailers - don't have this experience.

[TucsonJim]

It sure sounds like you have a valve that is not closing all the way.