Fixing Leaky RV Waste Water Value

Leaky dump valve?

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Fixing forever the Nasty Sewer Valve Leak

We among the RV motorhome owners who are frequently hassled by a slow leak in either or both the gray and black water holding tank valves.

In our case, it has been the persistent small leak in the gray tank valve. Sometimes it produces a small drip from the cap that covers the outlet to the sewage system. Because I know it is gray water, I’m not too bothered by it. But my wife is; she worries other people at the campground might see it leaking. Other times the cap doesn’t leak but when we are at a RV dump station and open the cap to install the sewage dump line and rush of gray water comes splashing out. That is an additional nuisance we both object to.

In my case I’ve tried various solutions like filling both gray and black tanks with vinegar and soap solutions to better flush out the drain lines. Sometimes bits of material get caught in the tank valve that prevent it from closing properly. When this didn’t provide a lasting solution, I broke down and ordered and installed a replacement gray valve. That solution didn’t last either.

On our unit, and I suspect many other RV layouts, the gray valve is actuated by a long cable. You push or pull on the handle on one end of the cable and the other end is attached to the gate valve. There seems to always be a bit of slop in the cable system; hard to “feel” that the valve is being entirely closed. I guess a final solution would be redirect the entire gray tank plumbing system so we have an separate outlet for the gray valve and can install a directly operated gate valve that doesn’t need a cable. Big job and it means the process of emptying the RV tanks will now be a two piece, two step system, hooking and unhooking the flexible sewer line two times to handle each of the tanks.

The Ultimate Solution to the Leaking RV Holding Tank

Well American innovation has finally come to solve our problem. It is a new product from Valterra RV Products. It is the T58 Twist-On Waste Valve. It is designed to replace your existing RV drain cap and it contains a secondary direct action waste valve. Your existing cap then twists on the open-end of the Twist-On-Waste Valve. The new valve gives you an effective second line of defense against the nagging leaky valve problem. What is nice about it is even if there is gray or black water built up behind the new valve, when you remove the cap to hook up your sewer line no water will come splashing out.

For less than $25 and minimal labor installing it, this nagging leaky valve problem is a thing of the past. You can order that new  Valterra T58 Twist-on Waste Valve from Amazon here

(amazon associate link*)


Installation is simple. Just unscrew and remove the outer dust cap from your present valve. Then screw on the Valterra Twist-on Valve in place of the cap you just removed. The valve handle component will rotate around to work at any angle. The place your old dust cap on the Valterra. That’s it. Now you have two lines of defense against that nasty dump valve leak.

remove the dust cap from your present valve.
Twist on the Valterra valve and install your dust cap on the end.

*We earn a modest commission on Amazon sales, that is paid by Amazon and does not increase the price of the product.