Holding Tank won't Drain

[td7298]

Hello! We have been in our 31RLSS for one month now and love it! We are fairly new to TT life. We have drained the black tank a few times already with no problems. Tried to empty it last night and it stopped draining after a few seconds. Still registers 2/3 full and we can see it's about that full when we look down the toilet. I've read some other threads on here and realize that it is most likely clogged. We tried flushing the tank, but that didn't work.

My question is - how do we find the problem and get rid of the clog? I've read in other threads where people have removed the valve and something else to access the bottom of the tank or the drain, but we have no idea how exactly to do this. Can someone please walk us through the steps? We are a little confused on how to access it because the underbelly is enclosed. Also, I assume that to remove the clog, the sewer hose will not be hooked up. How do you keep it from going everywhere once removed?

Again, we're pretty new to all of this, so we may not know the technical names of some of the parts. If this is answered someplace else in the forum, please let me know. Thanks for any and all help/advice!!

BTW - each time after draining, we have put in a couple gallons of water and liquid chemical before using again. We use TP made for RVs and we don't go overboard when using it.

Dina & Tim

 

[2010augusta]

Well you got a problem... You can't remove the valve with stuff in the tank or 30-40 gallons of "stuff" WILL pour out. I would play with the valve and open and close it several times and hope that something gives and lets everything drain.

 

[boatto5er]

If you aren't able to get it unstuck using Alan's suggestion, I'd advise you to take it to your dealer and them "fix" it. Sometimes the cutout from where the drain pipe attaches will get left in the tank and block the drain. The only other thing I can think of is to drive it around making a lot of turns and stops and hope the action of slinging the contents arounds loosenes whatever is causing the blockage.

 

[Two Hands]

Some other thoughts: are you sure your tank is full? In our Big Horn you can't see down into the holding tank because of the bend in the pipe. Our black tank usually shows two thirds full even when we know it isn't. We blame this on being off level and, mostly, on toilet paper stuck to the sensors. After three or four good flushings through the black tank sprayer the sensor reads empty. Before we had a black tank sprayer we used the clear plastic elbow with the hose connection to rinse out the black tank.

 

[JohnDar]

If the valve seems to function freely and there's no resistance to fully closing it, it may be something in the soup itself. Sometimes, the TP and/or other "items" can get hung up at the valve opening from the tank and create a dam. If you have an RV store nearby, get a DrainKing or HydroFlush adapter for the sewer connection and try backflushing the line. Run the water up the piping for a bit, then shut it off and let it drain. You may need to repeat this a couple of times to get the logjam to move. Even if it is construction debris, backflushing may help to dislodge it, or at least move it enough to allow the tank to drain. BTDT, even with the Bighorn and the black tank flusher. One solution may be less fiber in your diet, the "items" won't be quite so stubborn to break up

 

[irvin56]

I have a flush king.

http://www.campingworld.com/search/...de+matchallpartial&Ntk=p_keyword&Nty=1&Ntpc=1

Just put on drain line. close FK valve and Open tank valve and fill tank from bottom. This will back flush anything in line.

I have done this all the time I dump. Works good also to flush Grey tank, as you get alot of stuff from your sinks also.

The tank flush helps but I find this is a great product and would not hook up my sewer lines without it.
Only need 1 bad day to figuer it out. Trust me

 

[SilverRhino]

2nd the Flush King

I have also used the Flush King with great results. First fifth wheel did not have a tank flush system.....so I thought the FK would be the next best thing......NOW......I have both.....and routinely use both!

Just my opinion.

Good Luck & Travel Safe!

 

[jmgratz]

If the tank is truly clogged you can drive around letting it slosh around or also pour a bag of ice down the toilet and then drive around. Many times this will cause the clog to break up and allow you to flush the tank.

 

[td7298]

Thank you!

Thank you all very much for all of the advice! We have the tank flush that comes on the trailer, but we are definitely going to invest in a Flush King. Sounds like it would be a good investment even if the valve never clogged.

 

[66Vettster]

TD7298, It is recommended that after you get the tank flushed (don't fprget to close the black tank valve) that you add at least 4 gals of water and chemicals. I usually mix a gallon of water with the right mix of chemical and then add 3 more gals of water. I also use the flush king to do a final flush and it works great after a couple of flushes.

 

[newbie]

My question is - how do we find the problem and get rid of the clog? I've read in other threads where people have removed the valve and something else to access the bottom of the tank or the drain, but we have no idea how exactly to do this. Can someone please walk us through the steps? We are a little confused on how to access it because the underbelly is enclosed. Also, I assume that to remove the clog, the sewer hose will not be hooked up. How do you keep it from going everywhere once removed?


Dina & Tim

You can only remove the valves on an empty tank. You'll have to get the tank unstuck before you can even consider removing the valves.

Also, I don't think you need to go to the dealer for a clogged pipe. I would try some of the recommendations on here and I am sure you'll get it unstuck!

Good luck- John

 

[irvin56]

td7298

It may be the handle has come unhooked from the valve.
If thats the case you will have to undo the screws holding under belly cover, and take cover off the area where the valves are to acess the level to the valve. and try to open it then.

Before I did that I would try, with the FK on. close the FK valve and hook up water hose to it. and add water from that to the tank. Make sure the dump valve on waste tank is openned.

With the valve on FK closed and water turned on, it should force the blockage back into tank. With the water turned on you should hear the water entering tank. That would tell you if the valve is open or not..

Also can try to fill the grey tank to full, run water hose into bathtub and fill that way.
When the bath tub does not drain anymore. Tank is full.
Then with FK valve closed, Open the grey water valve. This will back flush the waste tank(black).

I do this everytime I dump to backflush the black tank. Only I don't fill the bathtub.(this step was so you get lots of volume and back pressure)
Even though it looks clean when dumping black tank. You would be surprised how the back flushing works, the sudden pressure and volume
of water going back wards stirs up the stuff really good.
Do it once and you will know what I mean.

Now I do the action with grey water to black for about 3 or 4 seconds. then close grey, open flush king and drain. then I repete this a couple of times. then I drain the grey tank to clean the hose.

Sounds time consuming but not really, you dump close valves back and forth a few times and flush hose.
I would say it adds about 2 mins extra time.
But it cleans tanks good.

 

[JohnDar]

A word of caution when using a FlushKing, DrainKing, or any name of backflush sewer adapter. Be real aware of which valve is open and which is closed. If you forget and have the tank dump valve closed AND the adapter valve closed and set up to backflush, you will get a wet surprise when the line between the valves pressurizes .

This is one of those operations where you don't want to walk away, make a sandwich, or be otherwise distracted.

 

[newbie]

I can honestly say that I have never gotten the urge to make a sandwich while dumping/flushing the black tank

 

[PUG]

Another thing to try is keep the outside cap on, fill the grey tank full and open both valves. This should push grey water into the black tank pushing a plug back. Let us know how you came out.

 

[JohnDar]

I can honestly say that I have never gotten the urge to make a sandwich while dumping/flushing the black tank

Why not?? Ralph Cramden's pal, Norton, used to eat his lunch in the sewers all the time . ....and awaay we go....a little traveling music!

 

[2010augusta]

Another thing to try is keep the outside cap on, fill the grey tank full and open both valves. This should push grey water into the black tank pushing a plug back. Let us know how you came out.

??? But how do you get the cap back off if the valves have been opened with the cap on and now you have a couple gallons of "stuff" between the cap and the valves. Even once you close the valves again you still gotta deal with the "stuff" in the pipes. I hate to deal with the cup or so of "stuff" that will slosh out of the pipes while in travel, I can't imagine dealing with a gallon or more.

 

[jmgratz]

I bought a cap that has a small garden hose type cap built in. I leave that open so when traveling so any "stuff" will just flow out into the wind. No messy hands.