RV Gray Valve Repair — REAL-TIME DIY Holding Tank Valve Replacement

The blade valves on your black and gray tank outlets are the only things standing between you and a tsunami of… well, you get the picture. It’s impressive how well they work… and how long they can last. Our gray valve is the original one that came installed on our RV when we bought it back in 2003. So it’s pretty amazing that it’s held up to full-time use all these years, quietly doing its job of controlling the gray tank contents, letting it out only when WE want it to, and keeping 100% of the 65-gallon-capacity tank fully contained the rest of the time, even while vibrating along thousands of miles of roads.

But recently we began to notice a couple of symptoms of a failing valve: (1) An occasional small drip from the handle itself (primarily when pulling it for dumping) and (2) A small amount of water accumulating behind the sewer pipe cap, even though both blade valves were closed. Thankfully, it was the gray valve that was failing, and not the black valve (hang in there fella)!

So we’re doing a replacement… and we’re doing it “real-time” with only the slightest bit of editing, so you can get a feel for how long a job like this takes, and how easy it is to do.

This is our second “Real-Time DIY” (after our recent propane detector replacement). Leave a comment below to let us know if you like this type of video and if you think we should try doing more of them. And be sure to share any advice you you might have from any experience you’ve had replacing your black or gray valves. Maybe we got lucky and ours was just particularly easy!

Recent & Related Videos:

Featured & Related Products:

Valterra 1.5″ Replacement Gray Blade Valve
Valterra 3.0″ Replacement Black Blade Valve (same replacement process, just a bit smellier ????????)
3/8″ Drive Reversible Socket Wrench with “Speed Rotation Ring” (Sorry… this is RIDICULOUSLY expensive, but was the only socket wrench we could find with the same finger-ring mechanism ours has)

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Don't Let a Sticky Black Tank Valve Make for a Crappy Day! - Lower 48 In Tow

Monday 5th of October 2020

[…] RV Gray Valve Repair — REAL-TIME DIY Holding Tank Valve Replacement […]

Shari English

Wednesday 18th of September 2019

I have a question. Does the new valve have an obvious orientation, or can it go either way? Never replaced the valve, but just bought a 22 year old NASH and need to replace valves.

TheRVgeeks

Hi Shari. Good question! Ours did not appear to have any orientation... and the installation instructions didn’t indicate that there was any special way it had to go in!

bob g

Sunday 8th of September 2019

Thanks for the video. It's always good to see how someone else did it prior to tackling a task yourself. One suggestion I would add is to have a small catch pan of some sort under the pipe when removing the old valve. That way if you have a leak it won't get on the floor of the bay. I also would recommend a little plumber's grease on the seals and valve prior to install.

Lloyd Stanton

Monday 9th of September 2019

That was great. When can you come over and fix mine?

Good tips, Bob.

richard ackroyd

You two probably already know this but for those who don't........ Before working on the black / gray valves dump the tanks with the wet bay side of the RV slightly lowered to get all of the contents out then raise that side of the RV to slightly higher than normal to stop anything dripping out when you take the valve (s) off.

Richard.

Good Idea!

Great suggestion, Richard. Never hurts to be REALLY sure the tanks are dumped fully before working on the valves!

Drew Mueller

One more thing....about greases: I use plumber's grease for seals that are constantly exposed to water- including a Valterra knife valve I use on a Flush King. It was greased over 2 years ago and I haven't needed to reapply since then. The stuff is from ACE Hardware but I'll bet any brand is fine...Very cheap- I think 2 or 3 dollars for a tube.

Thanks Drew!