Black water tank won't drain

[Morich]

We may never know if the OP doesn't come back to tell us what they found but I suspect this is more than the "normal" situation if the right treatment and water were added. I find little trouble if things are done right when it is only the normal, however, I'm guessing this is a broken valve. Getting used to what the pull action feels like versus when it's broken can help.

[71_340]

I agree with you on a bad dump valve. There is now way that you can have so much solids in your tank that they almost completely block the drain.


If it was mine I would verify that the valve does not move and then just cut the square portion of where the valve plunger goes in and out. That will give you access to the actual valve plate so you can grab and move it and drain that way.


There is no way I would just unbolt the valve and take a waste shower, neither will the mechanic at the dealership.

[cptrick]

I was going to mention the ice thing but it looks like someone beat me to it. Worth a try and just cost a bag of ice and a little gas.

[Sheilag1848]

I am holding tank chemical trained user LOL. Honestly, I spent about 3 hrs chatting with the different manufacturers of those chemicals and learned a ton. Mostly those are all almost worthless unless all you need is to get rid of smell. BUT, if you want to BREAK DOWN THE SOLIDS....you need ENZYME chemical. That ENZYME is the ONLY thing that will breakdown the solids and allow the tank to be fully drained. Camco brand BLUE color is the one I buy all the time and I have never had an issue - been rving since late 70s.I'm sure there are other manufacturers of an ENZYME product and guessing those will all work as well. Dont worry about not getting a nice smell...once the solids are disolved and sent down the drain, a quick back flush to rinse the tank will eliminate all those human orders.

[mudslidemary]

So sort of like a power washer?

[Sheilag1848]

Well...power washer will have a force to it, i.e. the water is propelled at a high rate of speed so it becomes sort of a blaster. An enzyme will cause the natural break down of the solid waste and allow it to either just drain along with the rest of the "liquids" and/or if any remains after dump is completed, you can back flush the remainder.

[Bubba48]

Sorry for the long delay in responding. I did have to replace the valve or rather have the dealer do it.
Disappointing that a 3 year old trailer that had only been used a half a dozen times would have this kind of failure.