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The Black Water Holding Tank Valve On Our RV Is Stuck Closed

by Tim
(Nashua, NH)

How to Fix a Stuck Holding Tank Dump Valve On Your RV

How to Fix a Stuck Holding Tank Dump Valve On Your RV

The black water tank valve is stuck, and I can't get it open. I have tried to flush it out with water to see if it would loosen the valve and open but no such luck. Any suggestions?

ANSWER: Hi Tim, well I am sure that you are not happy with this situation. I am hoping that you are hooked up to a sewer. Whether you get the RV Waste Valve open or not it sounds like it is time to replace it. Luckily they are not that expensive or that hard to install.

If your Black Water Tank does have water in it, I would try dumping a whole bottle of original liquid Dawn Detergent In the holding tank and let it sit for a while. You would be amazed at how much crud that Dawn breaks up. It could also act as a lubricant if it reaches the valve.

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You do not tell me whether you have a motorhome or a trailer, but if you are willing to drive the motorhome or pull the trailer around a little bit, I have another suggestion for you. Dump the bottle of liquid Dawn down the toilet and get the motorhome or trailer ready to hit the road, and right before you leave, dump about 10 to 20 pounds of bagged ice down the toilet.

This way, while you are going down the road, the ice cubes will rattle around in the tank, also stirring around the liquid Dawn, and this may be enough to free up whatever debris is keeping the sewer valve from opening. I know
this all sounds kind of stupid, but it works, and once you get the tank dumped, it will be nice and clean.

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Once you are done with your little road trip, you will need to hook back up to the sewer and try to open the RV Waste Valve again. You may have to pull real hard to get it open. I cannot tell you how hard to pull. Before pulling on it, you might want to tap the handle of the waste valve with a hammer and the vibration from that tapping may also help free it up. I cannot tell you how hard to tap it, but I know that right about now, you may be ready to turn a tap into a real hard overhead swing with the hammer, so you may have to use a little bit of restraint when you get to this part of the process.

If after all the agitating, flushing, hammering, and pulling, the valve still does not free-up you may have to take your RV in to have it repaired by a qualified RV Technician, or you can check in your area to see if there is a mobile RV service that can come to you to perform the repair.

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I hope that one of the solutions above work for you.

Do you have any suggestions or comments on this topic? You can add them to this page by clicking on the "Click Here To Post Comments" link located near the bottom of this page.

Happy RVing

RVing Al

Comments for The Black Water Holding Tank Valve On Our RV Is Stuck Closed

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Rating
starstarstarstarstar 		Finally something worked!
by: Anonymous

I have tried everything to get the black tank to drain. Snaked the lines, drilled a hole, baking soda vinegar trick, and everything else under the sun. Poured a large bottle of Dawn and three pans of hot water, stomped around to make vibration so soap would agitate, and the whole tank drained in 30 mins.
Rating
starstarstarstarstar 		Easy fix
by: Anonymous

Tap on inner gate with a 2x2 and hammer. Tap all around inner circumference. This was enough to break the seal that had been made.
Rating
starstarstarstarstar 		An easy fix for me
by: John

I bought an older Scamp to remodel. Fortunately there were no leaks in the water system including holding tanks. However, when I went to dump both tanks (after testing by running water in sink, shower and stool) I found both valves were stuck. Not knowing whether black water tank had been emptied after last use, I was somewhat concerned. So on line I went looking for an easy solution to getting the valve to move- finding none I was preparing for the upcoming mess when I would have to remove the valve the next day.

Fortunately I had some errands to run before tackling this "dirty job". On the way back to the camper while pondering the up coming "mess", it occurred to me that I might actually be able to unstick the valve by using a short 2 x2. I could put it up into the valve gate and gently hammer on the slide all around the circumference. I then also tapped on the pull handle. After putting an oil pan beneath the gate i slowly tried to open the gate. And it worked. Finding there was only the test water that I had put in the stool, I was able to drain it out into the oil pan. I now can take the valve off and replace it.

This worked for me and hopefully it might work for you.
Rating
starstarstarstarstar 		Black Tank Nightmare
by: Lynda

So I pulled my handle for black water tank and the handle came out. Broke off inside. I have opened up the end of the valve to see where the handle attaches and used needlenose to try and pull it but to no avail. Here is my question. Is the pipe at the drain end the same size as the valve replacement which is 3". I am heading to Lowes to hook up a concoction that will allow me to drill open valve without too much mess so it will at least drain enough to replace the valve.
Rating
starstarstarstarstar 		Stuck valve
by: Scotts

Have stuck valve on black water tank,handle pulled all the way out.need to dump.😬
Rating
starstarstarstarstar 		RV Black water
by: Anonymous

If your rv waste is full and your Handle pulls all the way out, how can you empty the tank so you can replace value?
Rating
starstarstarstarstar 		Black Tank Valves
by: John


Vaseline

Here's another hack for both the toilet valve and the black tank pull-valve. I use Vaseline on the toilet valve to keep it lubricated, and I mix a handful of Vaseline with a kettle of hot water, then dump it down the toilet. The Vaseline lubes the pull valve and keeps it from sticking. It also cleans off the walls of the tank. I've been doing this since 1997 [the age of my motor-home] and have never had to [knock on plastic] replace a black/gray tank valve yet.
Rating
starstarstarstarstar 		The correct products for a stuck valve
by: Anonymous


Thetford Drain Valve Lubricant

Thetford makes the correct product to keep this from happening, its called Thetford Drain Valve Lube. They also make products to keep the tanks clean. They are Tissue Digestor and Tank Blaster. Homebrews just don't work as well.
Rating
starstarstarstarstar 		IT WORK2
by: AIRSTREAM2

DONT HV 2 SIGNIN AMAZING! AWAY WE GO = DOLLAR TREE DISH SOAP SOAK 24 ROPE ON PULL HANDLE TAPP TAPP TAPP TAPP SEE BIT OF WATER THEN FLASH FLOOD THANK YOU!
Rating
starstarstarstarstar 		Black and gray rv valve maintenance
by: John


Valterra Valve Replaceable Seals

Ok. If you can feel the black water valve getting hard to pull, (this so you don't get it stuck).

Drain the black tank. If you have the time to let the tank dry do it a lot less messy. I did not. I pulled both valves and replaced the seals. Grey and black. Valterra 3 inch valves have replaceable seals. The black valve had so much hard water I had to replace the whole valve. It was only 12.00

Then coated the seal, shaft, and gate on the valve with silicone grease. Ok if it has gone way too far and the valve is totally stuck you may have to call a septic guy and have them pump out the toilet. Yuck. Then replace the manifold and both valves. Mess mess. A little preventive maintenance
Sure is easier. I am going to completely dry the system out and replace seals and the whole valve if needed. Once a year at least.
Rating
starstarstarstarstar 		Stuck in "little" road trip
by: Anonymous

Dear Buck

Thank you so much for your hands on practical step-by-step advice. I have been on this "little" road trip with my motorhome... the valve opened FINE 8 months ago but the sewage got stuck Ed up...so I'm HOPING to poke it with/ a long green stick to perhaps get it FLOWING again...any suggestions 🤔
Rating
starstarstarstarstar 		sewer valve fit is too tight
by: joe

I had a very hard time getting the broken black tank holding valve out from between very tight fitting pipes. They would not bend enough apart to fit both new gaskets in with the new valve, and had to leave one of them off in order to get the valve in (and it was getting late in the day and getting dark). So some leaking now and I want to put this in correctly. Would you recommend cutting and refitting the side pipe to give a little more space? If doing a modification like this, I'm thinking then of replacing some of the pipe leading to the valve with some flexible tubing so it will remain very easy for future repairs. What would you say?
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starstarstarstarstar 		Broken valve
by: Anonymous

Hi I broke the valve loose from the black water tank , now I can't empty the toilet. My trailer is a 1978 Holliday travel trailer.
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starstarstarstarstar 		Cleaning black water tank
by: Earnue


Bleach


Before leaving on a trip I run water into tank , add a cup of bleach and dishwashing liquid to clean sensors while you drive . Worked pretty good
Rating
starstarstarstarstar 		HANDLE BROKE OFF THE VALVE, TANK FULL. HELP
by: Anonymous

LDF PLEASE COME BACK HERE IF YOU CAN HELP.
Rating
starstarstarstarstar 		Valve seems to be stuck closed
by: DeeAnn

I ended up calling my RV Repair man and he drilled a hole thru the pvc pipe I had going to the septic tank and snaked the black water tank. Paper had clung to the valve and kept it from closing tight. He said to always rinse the tank really well each time it was emptied and to keep a lot of water flow at all times when flushing. Solids had built up inside blocking the opening. It was quite embarrassing but has never happened again. Sometimes you just have to call for help :)
Good luck to all!
Rating
starstarstarstarstar 		Building tiny house
by: Tj

My black tank was clogged and this method helped me fix it 100%. Thank you!
Rating
starstarstarstarstar 		Black tank
by: Anonymous

I went to open my black tank and the handle pulled all the way out. Is it something I could do or not? Thanks
Rating
starstarstarstarstar 		it works!!!!!!!!!!!!!!
by: Sam

so our cable was REALLY tight...we were afraid we were going to have to cut into the underbelly and replace it....we tried this first and OMG the cable works as good as new!

BTW we used generic soap from Dollar Store and it worked (didn't have any Dawn)
Rating
starstarstarstarstar 		BROKEN HANDLE
by: Anonymous

I TRIED TO EMPTY MY BLACK WATER TANK AND THE HANDLE PULLED RIGHT OFF. I AM HOOKED UP TO A SEWER BUT NOTHING CAME OUT. I TRIED TO PUT THE HANDLE BACK IN AND IT WOULDN'T GO. I WAS GIVING THE TANK A CLEANING TREATMENT SO I KNOW IT IS FULL. HELP.
THE CAMPGOUND I'M IN IS SEASONAL BUT THEY CAN'T HELP ME. I AM CALLING RV DEALERS RIGHT NOW. I CAN'T
DRIVE IT ANYWHERE. MY TRAILER IS IN A PERMANENT SITE. AGAIN HELP
Rating
starstarstarstarstar 		my cable actuator broke
by: Anonymous

my handle wasnt stuck like the others ...the cable broke when I tried to open the black water...now I don't know how to empty it. I can't find any specs on how to replace it. mine is on an 04 mobile suite...its in the underneath compartment...so I cant let the black water pour out under there...help!
Rating
starstarstarstarstar 		stuck black water valve
by: Anonymous

my black water tank valve was stuck shut. I used your trick with dawn and it worked like a charm. thank you.
Rating
starstarstarstarstar 		PENETRATING OIL
by: Anonymous

I USED BLASTER PENETRATING OIL ON THE VALVE AND LET IT SET FOR A COUPLE OF DAYS AND IT LOOSENED IT UP ENOUGH FOR ME TO OPEN THE DRAIN AND THEN I REPLACED THE VALVE.
Rating
starstarstarstarstar 		Valve seems to be stuck closed
by: DeeAnn

This has just happened to me. I am in hopes that the valve is just stuck and not bent or broken. I can push the lever in and pull it out but only a little water comes through. Maybe a few gallons a day. I am semi-permantly set up in my space so cannot hit the road, but will try the soap trick & see if it helps.
I took off the drain pipe outside (pvc instead of slinky hose) and pushed a piece of garden hose up the pipe toward the tank and hit a solid wall of metal or plastic. Then I tried the same method inside down into the blackwater tank. Same result. So even though the handle is pulled to open outside...the valve still seems to be closed.
Any more ideas?

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