Black tank flush

Ranger431

Senior Member
Joined
Nov 1, 2010
Posts
413
Wanted to see if anyone had any ideas on this....

My black tank flush doesn’t seem to be allowing any water into the tank. It worked fine last year. After winterizing, I have a hose (with and without) a dedicated valve and it is not allowing the water to flow into the black tank. Any ideas on what could be preventing the flow of water into the black tank flush system?
 
The only things I can think of are some obstruction in the line to the tank or a stuck check valve. The check valve is there to prevent back flow but should open to allow water into the tank.
 
I agree with 2edgesword: It's probably the check valve. Mine locked up several years ago. I was going to replace it, but it's inside the kitchen cabinet and is impossible to reach (at least for a full ground, somewhat overweight man). So I bought a Camco toilet cleaning wand. I just run a garden hose through my front door and into the bathroom, attach the wand, open the flush valve on the toilet, and insert the wand into the tank. The wand has a shut-off on it, so I turn it off, go outside and open the black tank valve and turn the water on. Then I go back inside and open the shut-off valve on the wand to flush out any "debris" while the black tank is draining. Contrary to what the Jayco instruction manual says, I close the dump valve for 1-1/2 minutes to let the BW Tank partially fill. Then I open the valve and allow the tank to drain. If needed, I'll repeat that process. Since I can turn the wand and move it around inside the black tank, I've found I get a much better flush than I ever did with the built-in black tank flush. After the second time I used it, the level indicators started working again. My wand had four "fixed" holes. A couple of months ago, I found one with a "spinner" on the end. It has both more water pressure and more water flow than the "fixed hole" wand had, so it does an even better job. Once the water coming out of the drain is clear, I shut the water off, then go inside to remove the wand from the hose, and feed the hose back out the door. With this new wand, the whole process only takes about 15 minutes. ;)
 
I agree with 2edgesword: It's probably the check valve. Mine locked up several years ago. I was going to replace it, but it's inside the kitchen cabinet and is impossible to reach (at least for a full ground, somewhat overweight man). So I bought a Camco toilet cleaning wand. I just run a garden hose through my front door and into the bathroom, attach the wand, open the flush valve on the toilet, and insert the wand into the tank. The wand has a shut-off on it, so I turn it off, go outside and open the black tank valve and turn the water on. Then I go back inside and open the shut-off valve on the wand to flush out any "debris" while the black tank is draining. Contrary to what the Jayco instruction manual says, I close the dump valve for 1-1/2 minutes to let the BW Tank partially fill. Then I open the valve and allow the tank to drain. If needed, I'll repeat that process. Since I can turn the wand and move it around inside the black tank, I've found I get a much better flush than I ever did with the built-in black tank flush. After the second time I used it, the level indicators started working again. My wand had four "fixed" holes. A couple of months ago, I found one with a "spinner" on the end. It has both more water pressure and more water flow than the "fixed hole" wand had, so it does an even better job. Once the water coming out of the drain is clear, I shut the water off, then go inside to remove the wand from the hose, and feed the hose back out the door. With this new wand, the whole process only takes about 15 minutes. ;)

I also leave my back tank valve closed while using the flush (I use both the in tank and the wand) BUT, I will never walk away from that task. I will not do anything else other than flush and dump the tank as getting distracted and not remembering the valve is closed will be disastrous!!
 
I also leave my back tank valve closed while using the flush (I use both the in tank and the wand) BUT, I will never walk away from that task. I will not do anything else other than flush and dump the tank as getting distracted and not remembering the valve is closed will be disastrous!!

+1

I set a timer on my phone, and/or my watch. DW thinks I'm "wasting time" standing there waiting for the tank to fill. But I explained to her in detail what could happen if I "forget" about it and it overflows. She stopped asking questions. She doesn't deal with the "waste management" function! LOL!!

To be fair and honest, I might actually do a couple other things while I wait for the tank to fill, but never more than a few feet away from the blade valve or the water valve, and never without a timer running.

I hope I never have to go after that check valve, I don't even want to think about how difficult that will be to access in my rig...
 
+1

I set a timer on my phone, and/or my watch. DW thinks I'm "wasting time" standing there waiting for the tank to fill. But I explained to her in detail what could happen if I "forget" about it and it overflows. She stopped asking questions. She doesn't deal with the "waste management" function! LOL!!

To be fair and honest, I might actually do a couple other things while I wait for the tank to fill, but never more than a few feet away from the blade valve or the water valve, and never without a timer running.

I hope I never have to go after that check valve, I don't even want to think about how difficult that will be to access in my rig...

I usually do the same thing. That’s what seemed odd. I waited a while to let it fill, and then when I pulled the handle and nothing came out, that’s a problem.

Never heard of a check valve failing - not sure if there’s anything I can do to fix that, but it seems like warranty work to me...
 
On my old motor home the check valve was part of the 3/4 water hose connector identical to the fresh water inlet check valve. I don’t know about the Jayco
 
Never heard of a check valve failing - not sure if there’s anything I can do to fix that, but it seems like warranty work to me...

Check valves fail all the time. Especially the factory ones that manufacturers bury deep inside inaccessible places!
 

New posts

Try RV LIFE Pro Free for 7 Days

  • New Ad-Free experience on this RV LIFE Community.
  • Plan the best RV Safe travel with RV LIFE Trip Wizard.
  • Navigate with our RV Safe GPS mobile app.
  • and much more...
Try RV LIFE Pro Today
Back
Top Bottom