Black tank line

Traveling Savages wrote:
New to the lifestyle and can't figure out why my black tank line fills while traveling. I emptied the tank the last two times before traveling....and made sure valve was closed. When I get ready to hook up, I opened the pipe to attach my hose and waste pours out. How is it getting past the valve?

My RV is nearly 30 years old. When I remove the outside dust cover to hook up the hose, nothing ever comes out.

It sounds like you are getting leakage past the valves.

An easy way to test is close both valves and remove the outer dust cap.

Then continuously flush your toilet, filling up your black water tank.

If you see water coming out of your dump connection with the gate valve closed, you have a leak.

If not, fill up your grey water tank and see if that is leaking at the gate valve.

FWIW.... I replaced the rubber seals from valtera instead of the entire valve assembly. Mine still leaks a little. I should have changed the entire assebmly- not that much more. I am guessing the blade has scores in it or some abrasion which won't allow it to seal completely eventhough I put new seals in. Pound wise/penny foolish....

On our current mh the black tank is ahead of the rear axel, with the dump station. The gray tank is behind axel, there is a built in pump to move the gray water to the dump station ahead of the axel. Because of this maybe a cup of gray water will always come out when the cap is remover when getting ready to dump.
Because of this I have built a way to dump the gray at a different location.

Dusty

Flushable wipes should never even go in your stick and brick toilet, let alone in your RV toilet.

In over 15 years owning my trailer I have only once ever had something spill out when I open the cap. I'm pretty sure somebody on the storage lot pulled the handle as a joke on all the stored RV's. Other than that the drain pipe is always dry when I remove the cap. I would say if you have more than a few teaspoons full of liquid drain out then you have a valve leak.

Next time you dump flush the tank a few times while rapidly cycling the handles to try to dislodge the paper stuck in the groove. If that fails you can either replace the gate valves or add an additional valve at the cap.

Replacement gate valve

Twist on valve

Never never never never never

never never

flushable wipes never never

never never never







never





ever

I have found in all my trailers that there is residual fluid that just doesn't get drained. It builds up at the sewer cap so you get your feet covered in ..... I put an end of line valve on my sewer line and now no feet getting wet. I also have a clear elbow at the sewer line end of my hose(at the trailer) so I can see when the grey water gets dropped to clean out the black water hose. Look here- https://www.campingworld.com/twist-on-valve-27868.html?cgid=sewer-connection#start=16&cgid=maintain-your-rv%2Fsewer%2Fsewer-connection%2Fsewer-adapters-valves-fittings

Has it always done this, or just recently? It is common for residual water to remain in longer pipe when draining. Then with travel/moving, it gets to the dump exit. If you are talking about a quart-half gal, this is likely your issue. More likely to be gray water though, than black tank water.

My galley tank has a long line to sewer exit, and has done this since new. My solution was to install sewer cap, with garden hose attachment and small cap. I can loosen small cap, hold hose under, open small cap to drain residual, before opening large cap to attach hose.

Jerry

If the valve is a pain to get at, see if you have enough clearance to another valve at the discharge point.

Assuming this isn't a new unit, replace the valve. They are cheap and easy to replace, the gaskets get worn after a while and leak.

How are you making sure the valves are closed? If you're having leakage, I would not rely just on the valve handle's location as an indicator. Do you do a water dump (pour a few gallons of water into the tank) after closing the valve to see if any leakage is occurring?