Black tank won't empty - stuck valve? Clog?

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Phil Hyde

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Hi all - went to empty the 'rear' black tank this evening, pulled the handle, and nothing happened.  Didn't feel any different than usual.  Could this be a sign of a clog?  Anything easy to check?

This is the 'rear' black tank, which because of it's location gets plenty of use.  We always leave the valve closed and empty it when really full.

Thanks in advance.
 

Phil Hyde

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When I pulled the handle, it didn't feel any different (no easier), which seems to be a common symptom of the cable coming loose.

I did notice, when pulling back and forth, that I heard a small amount of liquid enter the pipe.

Hasn't gotten below freezing here.  41 was the lowest I've recorded.
 

Gary RV_Wizard

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At our Silver Springs FL home
Do you have a waste line fitting that has a hose inlet on it? Try back-flushing with the valve as open as you can get it.

http://www.campingworld.com/shopping/item/RV-Hydro-Flush-45-Degree/14496/&?&affiliateid=3274&cvsfa=2734&cvsfe=2&cvsfhu=3134343936&gclid=COaY-7e5zLMCFQU5nAodnSEAWw
 

SeilerBird

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St Cloud Florida USA
I bought one of those back flushers like Gary posted and it didn't work. The problem is that in order to work it needs to be a straight shot from the hose into the tank. My tank has a 90 degree elbow between the sewer hook up and the tank. But you should get one anyway. It is great for monitoring the output of your tank. When the water runs clear the tank is clean. They also make then straight instead of curved and that would be the one I recommend.

However I did have extremely good luck with this tool:

http://www.amazon.com/Camco-40074-Flexible-Swivel-Shutoff/dp/B0006IX7YC/ref=pd_sxp_grid_pt_0_0

Open the toilet valve (with the water pump off) and push the hose down into the tank. It will clean the inside of your tank until it is spotless. Move the hose around occasionally. You can monitor the success with the clear plastic goody. The first time I used it I had junk coming out of the black tank for an hour. Lots of junk, gobs and gobs of it, all from the previous owner.

Both items are available at most Walmarts in the RV section of automotive.
 

Phil Hyde

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Out of curiosity, I opened the tank when I got home this evening.  A little bit of liquid started to come out.  So I closed the valve, and filled the tank up as full as I could get it.  Went back outside, opened the valve, and WOOOOSH!  So it would seem that I had a blockage.  When I get some time this weekend I will do a more extensive flush of both tanks.

Thanks much for the advice.  :)
 

BruceinFL

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Mar 12, 2005
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3,205
I use Pure Power Sensor Power in each tank at least once/year. Fill the tank, leave it sit for 24 hrs and then dump. Works like a charm. Check it out here: http://www.opproducts.com/SensorPower.html. BTW, it also is recommended by Drainmaster to keep the valves cleaned up and free.
 

Mopar1973Man

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New Meadows, Idaho
Phil Hyde said:
Out of curiosity, I opened the tank when I got home this evening.  A little bit of liquid started to come out.  So I closed the valve, and filled the tank up as full as I could get it.  Went back outside, opened the valve, and WOOOOSH!  So it would seem that I had a blockage.  When I get some time this weekend I will do a more extensive flush of both tanks.

Thanks much for the advice.  :)

Typically when I return home I will fill all the tank with fresh water again and then dump again this just insures there is no left over sewage left behind. So far I've dumped a few time before heading home to find solid matter still visible through the toilet. So load it up and dump it again at home. I'm lucky yo have a sewer clean out right next to the driveway so I back in and dump. Water faucet is just a few feet away.  8)
 

Phil Hyde

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Sep 5, 2011
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United States
I should probably clarify that by "got home this evening", I meant when I returned to the trailer.  It hasn't moved in almost 5 months.
 
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