Black Tank Dump Valve Leaking

[Flyer]

I bought this trailer from an individual about a month ago. I'm near certain my black tank valve is leaking.

Does anyone have any suggestions or howto or even pics of what I would be gvetting myself into?

I know there's an underbelly but I'm not sure about removing it or how much room there is to cut/remove the valve without having to replumb half of it.

[ncitro]

Easiest short term solution is a twist on gate valve right at the outlet. That prevents spillage when you take the cap off. After that yes its removal of the coroplast underneath (screws around the perimeter), and then removal of the valve and replace. I have done it, its not bad but not pleasant either. Its hard plumbed to the Tee that links it to the grey tank so the whole assembly comes out together. Cate&Rob has a write up on his where he cut them apart and spliced it with rubber boots to make individual valve servicing possible.

Here is the twist on valve:

https://www.amazon.com/Valterra-T58-...ps%2C92&sr=8-3

[Country Campers]

Easy button place this on the end of the drain where you attach the sewer hose Amazon.com: Valterra T58 Twist-On Waste Valve, Mess-Free Waste Valve for RV's, Campers, Trailers : Automotive. I have used this for the last 5 years and do not have any surprises when opening the cap on the sewer connection.

Dropping the underbelly is the best way to get at the tank valves. There are screws around the perimeter attaching it to the frame.

Brian

Neil beat me to it.

[Scott'n'Wendy]

It's probably not leaking....just sub-optimal plumbing. After draining there is material left in the drain line after the valve. That won't drain....then ...You drive the trailer to a new spot and you get a little surprise the first time you take the cap off. It's a common occurance.

[Flyer]

It's probably not leaking....just sub-optimal plumbing. After draining there is material left in the drain line after the valve. That won't drain....then ...You drive the trailer to a new spot and you get a little surprise the first time you take the cap off. It's a common occurance.

That is the only thing that has me second guessing.

As a routine, I ALWAYS drain and flush the black tank, then drain the grey tank. My thought process is cleaning out the pipes and hoses with grey water before putting them up.

I get chunks out though and don't think I should with the process I explained above.

[Flyer]

To the others ... I have that valve already. Between my OCD and my inner perfectionist I would prefer it fixed right.

[Cate&Rob]

To the others ... I have that valve already. Between my OCD and my inner perfectionist I would prefer it fixed right.

I can relate to this perspective LOL ! I got into this a few years back . . . replaced all my gate valves, re-routed the pull cables (following cable manufacturer guidelines), modified the drain manifold so that valves can be individually removed, even came up with a way to put grease zerks on my gate valves. Then I installed opening doors in the underbelly to keep things accessible. Everything has been problem free since “making it right’. All is documented elsewhere on this forum if you are interested in going down this rabbit hole.

Rob

[Scott'n'Wendy]

That is the only thing that has me second guessing.

As a routine, I ALWAYS drain and flush the black tank, then drain the grey tank. My thought process is cleaning out the pipes and hoses with grey water before putting them up.

I get chunks out though and don't think I should with the process I explained above.

I do the same......and.....I can verify....using the above procedure you described...it will appear you have a leaking black tank....and you don't.

[JBill9694]

Flyer, a question for you to help determine if you have a bad valve or not.

Between draining is the twist on valve open and black tank drain valve closed?

If yes, and you still get a good gush when you open the black tank valve then you probably do not have a bad drain valve.

If no, try opening the twist on valve while leaving the black tank valve closed, If there are no solids in between the valves and the flow stops after a minute or so then you probably do not have a bad drain valve.

[03Griz]

What I have seen is toilet paper gets caught in the lip where the valve closes, so the valve can't close all the way, not sure how to get that out without taking the valve apart. Perhaps have the black tank open, leave the cap on put enough water in the tank so that the valve is under water, then throw some breakdown chemicals in the tank and let it sit for a couple days? That might eat the paper...... Orientation of the valve could be a contributing factor and the valve closing downward like a guillotine would be worse as the stuff could sit there waiting for the valve to be closed and pack into the lip.