Black Water not draining

[Gcworth]

Ok so my black water holding tank is full. When I pull the lever i can hear just a tiny bit of fluid come out then nothing.

Is it common for the inner part to break off the metal shaft or are they pretty well one peice and maybe I have something clogging the outlet instead?

I poured a bottle of the blue stuff in there and some blean to try and break down any possible blockage but Im thinking becasue the tank is full it might not have been enough if thats the case.

If in fact it is not a blockage and the gate/door thing is broken, what are my options to drain the tank so I can repair it?

Thanks,

[Gcworth]

Does that blue stuff in the RV section actually break down solids or just mask the smell ?

[doxiemom11]

Buy a box of water softener - that will help soften and break down any solids. Check in the laundry section at your local market.

[HappyKayakers]

Gcworth wrote:
Thanks all.

I didn't leave the cable open all summer. I just went we have been using it since the summer. I was pulling the valves and just assuming the black was draining with the rest.

Here over the last few weeks is when I noticed the gauge was showing it was not empty.

I got a 25 foot snake I'll tryout this weekend once I get down there.

I assume dumping a gallon of bleach wouldn't hurt anything right? Just trying to think of chemicals that could help break down any solids to assist if it's not s broken cable and it's just a clog...

Gauges are notoriously inaccurate. If that's your only concern you may be getting worked up over nothing. Bleach will disinfect, not break down solids.

[Gcworth]

Thanks all.

I didn't leave the cable open all summer. I just went we have been using it since the summer. I was pulling the valves and just assuming the black was draining with the rest.

Here over the last few weeks is when I noticed the gauge was showing it was not empty.

I got a 25 foot snake I'll tryout this weekend once I get down there.

I assume dumping a gallon of bleach wouldn't hurt anything right? Just trying to think of chemicals that could help break down any solids to assist if it's not s broken cable and it's just a clog...

[Old-Biscuit]

Gonzo42 wrote:
I know this idea is not too likely but it happened to me. When dumping my black water to my sewer cleanout I had almost no flow. I started to loosen the connector and heard leaking air.

When I propped open the toilet flush valve, the water flowed. Apparently when closed there was a tight enough vacuum seal that the water would not flow. Need to turn off the water pump at this time, too, or the system tries to pump more water into the toilet.

Open dump valve and no flow until you open toilet flush valve....????

That means you black tank vent line to roof is blocked (birds nest etc)
Or the vent line inside tank is below liquid level and can't vent to roof.

You need to clean the vent line.

[doxiemom11]

Had neighboring campers with that problem - previous owner had let crud build up and left valve open. Their first clue was the odor, then no draining. They called the company that comes to the campground and pumps tanks out and explained. They came and sucked it out thru the toilet - then did a power flush with their hoses - sucked back out (all kinds of crud) and then gave them some stuff to put in over the next couple of weeks to help soften and get rid of anything left. They then came back, did another power flush until water ran clean and they had no further problem. Couldn't believe -- only charged them $79 to do all that.

[Joe417]

I think what you are saying is you left the valves open all summer and "assumed it was draining".

If you had the valves open all summer, your problem may be that the solids built up in the tank stopping the drain pipe up. Since there is no P trap to block evaporation in the 3" drain, liquids run out and allow the solids to dry hard, you use it again and more builds up until you have a problem.

That also allows solids to build up in the valve slot which can stop it from working.

If some liquid runs out, you may have a "solids" dam built up at the drain. I would buy a clear elbow and see if it drains a little when you have it open and run water into it. If it does you may be able to keep running water until some of the solids break up.

If nothing is running out, I would use a Flush-King and back pressure it to try to open it up.

If it's a straight shot from the outlet to the tank, I don't advise a broom stick, unless your real real fast.

If this is the problem, never leave the valves open. Drain them when you need to but don't let them dry with solids in them.


I can assure you the broken valve scenario would be a more pleasant undertaking unless the pull rod is completely missing from the valve.

Good luck.

[Taxman2004]

Had a similar problem. When I opened the valve gate it did not come all the way open and only got dribles. Closed it and reopened all the way and it worked. Also, my unit tends to clog in the sewer pipe just below the toilet flap. Periodically, I have to use a sewer snake to unclog it. If you have that it could cause the suction the other poster was referring to. You cannot count on the gauge, they usually always say full because the controls are contaminated. Only way to test for sure is to open the black water valve, have someone monitor the outside and try to use the toilet. I would flush, pour a gallon of water, use a hose and finally a sewer snake from the top down. These steps in that order will tell you whether your tank is full and not dumping. After dumping you should add one to two gallons of water. It will help with the operation of the toilet and minimize the smell. If that doesn't work, the only other option I can think of is to open the black water valve and use a snake from the bottom. That obviously risks making a very big mess, so be careful where you do it and have a change of clothes and shoes handy if you get to that point. I have also heard of newer units that have a cutout piece of plastic that is stuck in the tank creating problems. Good Luck

[Gonzo42]

I know this idea is not too likely but it happened to me. When dumping my black water to my sewer cleanout I had almost no flow. I started to loosen the connector and heard leaking air.

When I propped open the toilet flush valve, the water flowed. Apparently when closed there was a tight enough vacuum seal that the water would not flow. Need to turn off the water pump at this time, too, or the system tries to pump more water into the toilet.

[Gcworth]

I do t think it's a cable. It has a handle that's attached to a metal rod that goes into the door and when you pull it, it yanks the door open.

I'm going back out there is weekend so I'll snap a picture. I may try blowing it out with a spare hose and see if it's a clog.

We have been using it since this summer. I pull all three valves and just assumed it was draining until I started smelling it in TE trailer. Looked at the gauge and saw it was full.

[RJsfishin]

How long since it was empty ?
How long did it take to fill it ?
How long has it been full ?
All in trying to determine if its a clog.

I would think if operating the valve (cable or otherwise) feels normal to you, the valve is opening properly.
In that case, you mite be on your own as to how to get rid of the clog.

Me ?? Maybe I would install a cap w/ a hose bib on the outlet.
Then push a hose nozzle up against the bib and give it a shot or 2,....see what happens,.....then go from there.:((

[2oldman]

I hope it's not that you haven't been using enough water!

[HappyKayakers]

If you have a cable operated dump valve, it's also possible that the connection has broken right behind the frame. If that's the case, you can drop a small portion of the underbelly and pull that cable. If you have a blockage at the outlet, your best bet is to get the valve all the way open and let nature/gravity take its course.

Before you go too much further, you should add a clear sewer extension to the end of your pipe so you can actually see what's going on instead of relying on sound.

[Old-Biscuit]

Sounds like you have a cable operated dump valve and can't actually see the valve.

Cable has pulled loose from valve stem....have to get access to valve and open using pliers on end of stem

Enclosed under belly?
Cut a 3 sided window then fold down to access valve (folded side towards front of trailer so when you close and tape it shut using eternabond tape or Gorilla tape