So we've gone dry camping twice in a new to me 2002 Cougar Fifth wheel. Both times we've had a blacktank/toilet backup issue. Emptying the black tank does not help. Yes I know about putting enough water in there and all that. It appears the solids/paper are just not making it into the tank and they back up by the second day to the toilet. The first time I poked it from the top with a rotorooter type snake while my buddy banged on the tank from the bottom in the area where the pipe goes in and it finally went. This last time I just poked it and it seemed to go easier this time but I'm not sure if it's a bad design or what. There are two 45 degree elbows on the way down because the tank is not directly under the toilet. I used to have a TT which never had this issue. How hard is it to remove the black tank? Any ideas? Thanks....

As a starter I would check the vent to make sure it is open. Probably 2 elows before the tank may not be the best design. You may want to check to see if there is some restriction in the elbows that is not getting completely cleared out.

WyoTraveler wrote:As a starter I would check the vent to make sure it is open. Probably 2 elows before the tank may not be the best design. You may want to check to see if there is some restriction in the elbows that is not getting completely cleared out.Well the double 45 degree elbows I really don't care for at all. As far as restriction at those elbows I highly doubt as I pretty much have visual access to the first 45deg and it looks pretty clear when it's not backed up. My hunch is that the issue is where the pipe dumps into the tank as it takes a couple days for the stuff to reach the toilet. If it is indeed a bad design I could easily sell it and find something else as I don't have a lot of money into it. I really do LOVE the floorplan and everything else about it for my use of occasional dry camping but dealing with this is NOT what I signed up for lol.

Add water and dish detergent then take it for a drive over a bumpy road followed by a dump.

My 5th wheel has two 45 degree elbows, one at the toilet flange and one where it dumps into the black tank. Never have clogs.Three common causes:1. The vent pipe for the black tank is clogged. Take the cap off at the roof and run a snake down the pipe or use a hose to run water down the pipe.2. Something is caught in the sewer pipe leading to the black tank. The toilet paper builds up and clogs the pipe. I've read where in the manufacturing process once in awhile stuff gets dropped down before the toilet is installed or kids drop things in toilets. 3. Dried up gunk has created a pyramid and it's partially blocking the entrance into the black tank.Number one cause is the vent clog so I would check it first.

krazymatt wrote:WyoTraveler wrote:As a starter I would check the vent to make sure it is open. Probably 2 elows before the tank may not be the best design. You may want to check to see if there is some restriction in the elbows that is not getting completely cleared out.Well the double 45 degree elbows I really don't care for at all. As far as restriction at those elbows I highly doubt as I pretty much have visual access to the first 45deg and it looks pretty clear when it's not backed up. My hunch is that the issue is where the pipe dumps into the tank as it takes a couple days for the stuff to reach the toilet. If it is indeed a bad design I could easily sell it and find something else as I don't have a lot of money into it. I really do LOVE the floorplan and everything else about it for my use of occasional dry camping but dealing with this is NOT what I signed up for lol.My previous TT was a great black tank design. Deep tank and no problems. My MH has a very shallow wide tank and I have to really pour in the water when I flush. In fact it is so shallow a couple of uses without a lot of water will start backing up right below where it empties into the tank. I try to make the bowl pretty full before I push the lever all the way down so lots of water goes in.

Black Tank Backing Up-Please help! | Good Sam Community

30 Replies

krazymatt
Explorer
Jul 08, 2015
On another note, that Camco flexible wand is designed quite well and provides plenty of power. I believe it's better than the permanent mount tornado type because you can move it up and down.
krazymatt
Explorer
Jul 08, 2015
IAMICHABOD wrote:
That is good to hear that you found the problem,and corrected it.
Hopefully you wont have the same problem again.

Maybe the previous owner used those so called flushable wipes,they will wreck havoc on a holding tank,they will never break down,just clog up everything. Never put those in a holding tank.

Yeah there's nothing flushable about them. I think they are the Clorox or Lysol wipes because they were all together as in a very long piece as those things are perforated so if you don't cut them they can be quite long. Maybe the PO had someone clean it before he sold it and they didn't know any better. Who knows.
IAMICHABOD
Explorer II
Jul 08, 2015
That is good to hear that you found the problem,and corrected it.
Hopefully you wont have the same problem again.

Maybe the previous owner used those so called flushable wipes,they will wreck havoc on a holding tank,they will never break down,just clog up everything. Never put those in a holding tank.
krazymatt
Explorer
Jul 08, 2015
Well I ran the flexible wand and mightve found my problem. After a few drain and wash cycles I saw what looked like a very huge piece of what appears to be Clorox or Lysol wipes come out. Afterward the tank actually sounds hollow when the wand head would hit the bottom and it would echo so there was definitely a big blob of that stuff likely causing the issue. I won't know for sure till the next camping trip but I feel pretty good about it now. Thanks for all the replies. I will update after I camp next time in the next month.
whs9841
Explorer
Jul 07, 2015
Can you change out plumbing going from the toilet to the black tank? That would save you from having to drop the black bank. I'm not sure what type of access you have to the plumbing, but running a larger diameter pipe from the toilet to the black tank may help.
Joe417
Explorer
Jul 07, 2015
I didn't read the whole topic, so if this is similar to other input please excuse the waste of time.

I've had the same issue with our 5th W. Before we found the real problem we did two thing to circumvent having it stop up. 1: Wife tested all toilet tissues to make sure it disintegrated quickly and 2. flushed twice anytime there was paper involved.

The rest of our "fix" is in the post below:

http://www.rv.net/forum/index.cfm/fuseaction/thread/tid/28451939.cfm

Didn't know how to make it a "clicky".
myredracer
Explorer II
Jul 07, 2015
There are many dimensions and configurations of holding tanks and some black tanks are very shallow while being long and wide. For these, it won't take long for the pyramid of poo to block the entrance into the tank. An outlet can be in the center or at the end. Poo does not somehow "melt" and flow around inside the tank and slide towards the outlet. It just sits there in a blob. There's got to be a better way...

Ours is like that and we can't get more than 3 days if doing #1 + #2. However, if doing just #1 and using the CG facilities for #2, we've gotten 9 days and maybe could have gotten more. Major difference. With our first TT, we never, ever once had an issue with use or dumping of the black tank. Wish we had the old tank back.

I doubt that the pipe extends too far into the tank as they use a flange on top of the tank that the pipe is glued to.

Always add lots of water before each use of the tank (3-5 gal.) and make sure the tank is rinsed out as well as you can. I leave the in-tank rinser on for 5 - 10 min., then fill the tank up and dump and I repeat if needed. We are lucky that we can look down into the tank to see if it's clean. If you have a built-in rinser, the head is just below the pipe into the tanks and I doubt that the spray reaches the ends of the tank very well, if at all and there must be "stuff" always left in there.

You could try a Valterra clear backflush elbow. You also try a length of heavy rubber-walled 1/2" garden hose and push it back into the tank and rinse and also down into the toilet. A CG employee gave us a piece of hose like this when we had a problem with our tank the first time.

Our owner's manual says to use Liquid Drano to clean the black tank if needed. Have done this once before and just did it again a week ago as our tank was getting to be a problem again and was always giving false readings. We have the Horst Miracle probes and it hasn't helped with false readings.

I would suggest trying the Liquid Drano method to get the tank back to what it was like when brand new. If you do this, never dump it into a private on-site septic system as it will cause serious damage to the drainfield.

If all attempts to clean the tank just haven't worked, I'd buy one of those USB pipe inspection snake cameras like this one on ebay and see what's going on inside (only around $10-$50). If the factory used an excessive amount of glue, you can have a bunch of "stalactites" hanging down around the bottom of the pipe which can impede the flow of #2 and TP into the tank like in photo. Easy to remove if pipe is vertical but not if there are bends into the tank.

Below is a diagram of dimensions of a 32 gallon tank. You can see how it shallow these things are relative to length and width. Outlets can be on the bottom, side or end.
krazymatt
Explorer
Jul 07, 2015
IAMICHABOD wrote:
Amazon does sell one type,cheaper.

Thanks for the link. I found a couple other companies that sell similar products. They're all around $100 to $150. I'll see what the camco thing does to it first. As bad as my situation is I doubt it will knock anything loose.
IAMICHABOD
Explorer II
Jul 07, 2015
Amazon does sell one type,cheaper.
krazymatt
Explorer
Jul 07, 2015
Hmmm, this could work by running it in from the toilet end then running it from the outside...

http://www.cloghog.com/