Wednesday, September 28, 2022


Ask Dave: Black water tank handle hard to pull open. How can I fix it?

Dear Dave,
It has become increasingly difficult to pull open my black water tank handle. I’ve been needing to use a claw hammer to pry it open. (I know that this is probably not ideal.) I have tried lubricating it with RV slide lubricant and that didn’t work. Please help, as I live in my RV full-time and need to dump often. Thank you in advance. —Chiara, 2020 Forest River Wildwood 40FDEN

Dear Chiara,
I tried looking at several factory videos and used for-sale photos to see if your valve and handle are connected directly to the drain pipe or if a cable is set up, and I can’t tell. The floor plan shows the bathroom on the curb side, so your black water tank will be over there with the drain handle typically on the other side. Some manufacturers run a solid pipe from the tank to the other side with the spade valve out in plain sight, like the in the photo below. Others have the actual valve at the tank and run a cable to the other side with the handle.

Fixing the black water tank handle: two areas to lubricate

Typically Valterra is the manufacturer of the valve, and they are now owned by Dometic. There are two areas that need to be lubricated for easy black water tank handle maneuvering: the shaft pushing and pulling the actual valve, and the rubber seal inside the tank. Thetford makes a drain valve lubricant that you pour into the toilet and it lubricates and softens the rubber seal. Sometimes the plastic spade valve can get stuck to the rubber seal, so it’s a good idea to do that a couple of times each year.

The next item to lubricate is the shaft which pushes and pulls the valve. I would not suggest slide room lubrication as it could clean away the actual lubricant that was originally in the shaft housing. Valterra recommends a silicone such as 3-in-1 or CRC Power Lubricant. I would suggest using that on the shaft. If you do have the cable type, you might need to take off the underbelly and lubricate the actual valve.

If lubricating does not help, then I would drill a small hole in the top of the valve housing, which is the square plastic piece, and lubricate inside the housing with the straw that comes with the CRC Lubricant.

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Stress-free RV black water tank cleaning and maintenance

They are every RVers’ most dreaded chores: emptying the RV’s black water tank and cleaning the black water tank. In other words, properly maintaining your RV’s sewage systems.

You’d be hard-pressed to find a more user-friendly and comprehensive RV black water tank guide than this video.

Click here to watch

Dave Solberg is a leading expert in the RV industry and the author of the “RV Handbook.”

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1 month ago

My valve was inside the belly near the tank. Had a long cable to the valve. Since there was a fair amount of work to get to the valve and the cable was long, I went a different direction.
I installed a electric Valterra valve and hopefully have solved the problem. It opens and closes in 1.5 seconds and appears to have solved this issue.

Bob Weinfurt
1 month ago

I did the same thing as Joe plus was able to spray some silicone up to the inside of the valve. It’s worked well for the past several years.

1 month ago

I’ve wrestled with this, and Nick is correct, it’s just better to replace than to try to keep old valves working.

Find an RV shop that is willing to replace your valve setup; let them look at it and order any parts needed. The morning of your repair appointment, dump, flush, rinse your tanks well, then drive up to the shop with the cap off so any stray water can drain out.

1 month ago

At some point, it is just easier to replace the valve. It is not expensive (less than $30) and is not difficult to replace (when the tank is empty). These are plastic pieces and a rubber gasket – they won’t work perfectly forever.

1 month ago

I did the “drill a small hole in the top of the valve housing”. It worked for me and I lube the valve and also handle several times a year with silicone lubricant. I used a self tapping screw with a metal washer and then a rubber one to seal it up. And only do the job when the tank is empty!

Samuel Yates
1 month ago

If things continually get worse, you could secondary valve and just add between the sewage line and the existing valve… Not a perfect solution, but could get you through.

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