We've been parked (in the Cameo fifth wheel) for several weeks in one spot on a site with a sewer hookup. I leave the gray open constantly draining out. Every so often, I drain the black tank. This time, when I went to drain the black tank - no glug, glug, glug - it doesn't seem to be draining at all. I am assuming all the tissue & solids have become impacted at the bottom and are blocking the exit port. We don't usually have any odor problems (or any other sewer problems at all until this) so we haven't used the sewer fluid/deodorant that helps with breakdown. I guess I'll try that first to see if that breaks the logjam.

RV supply stores like Camping World sell wands you hook to a garden hose. Run the hose through a window and shove the wand down the toilet to spray the insides of the black tank and unjam them. They work. There are also kits to install a built-in sprayer than many like to use where you attach the hose in the wet bay. It sounds like you are draining the black tank when it is not very full, it should be at least 2/3rd full when you drain it. When the tank is mostly full it drains fast and takes away everything. Dumping when it is not very full puts you in a situation like you describe, affectionately called the "pyramid of death". Wait for it to pop water back up when you flush since there is little room for the water and waste to go, then dump the black tank.

Thanks Bill! I do have that Sani-Flush system but was unsure whether to use it under these circumstances (I didn't want to compound the problem). Do you think that filling it with water via the Sani-Flush system would free it up? Of course, the level sensors don't work but that seems to happen to everyone I talk to, so I can just monitor the water level from inside with the toilet valve open.

Yes, the Sani flush is exactly what you need. If you almost fill the tank, that should unblock it and then you are good. What a lot of people do is flush the black tank after emptying it every 3 or 4 times. Just leave the dump valve open and flush it for 5 or 10 minutes.

Thanks Fred - That's what I'll do.........

Since we're not paying extra for water, we flush our black tank after every dump. After reading Howard's last blog, I think we'll replace that clear elbow we had from the old trailer and flush the grey tank as well...

Could be the drain is plugged. Had that happen a couple times. My solution was to purchase a closet auger. I know some 5th wheels have long pipe runs from the drain valve to the tank so this may not work for you. You will need to be able to snake all the way to the tank.

If you're real brave you can unhook the hose and shove a stick or snake(auger) in the black water pipe to try and dislodge the "Pyramid of Death". This only works if the liquid has all drained out and you are sure only solids are left. Break up the solids. Replace the hose, close the valve, fill the tank with water and then dump. You should hear "Swoosh" instead of "Glug, Glug Glug....".

Most honey wagon operators will not hook up directly to your drain valve. If they did, they just might collapse your tank. Most of them use a bucket and drain slowly into the bucket and put their suction hose in the bucket. I would never be so brave as to push a stick up into the drain valve. MAN, that would be a mess.

That's not been our experience Ken. We've not had that many, but every honey wagon, maybe 5-6, has hooked directly to the discharge pipe, without problem. Aren't all black tanks vented to the roof, which should prevent collapse from suction? I agree with you on the stick up the drain. No way, Jose!

Fred, based on what I have seen of the vacuum exerted by the honey wagons, the 1-1/2 inch black tank vent would never keep up with the suction. I guess if the operator was very careful it might be OK, but I would be as nervous as a long tailed cat in a room full of rocking chairs. We use probably too much water when we flush, but thankfully, we have never suffered the dreaded brown tower of death. A friend did though, cost him a bunch of money to get it cleared. We also use a digester called RVTrine, seems to break down waste rather well.

We are on full hookups 99% of the time so we use a LOT of water and no chemicals at all.There is a certain sound when flushing you will learn means it is full.Might be overkill but I use my black tank flush every time I dump. I do plan to get a flush king so I can back flush both grey tanks also to clean soap scum and food particles. As for the honey wagon I've never even seen an RV type but the trucks that emptied our septic system in our former stix and brix was very powerfull. I would not be willing to let him hook to mine.He could empty an 1100 gallon septic tank in 30 minutes so lots of suction.

-- Edited by Racerguy on Wednesday 13th of October 2010 05:52:21 PM

FWIW, I have used my closet auger on both my black and gray tanks. I know it sounds crazy. I had visions from the RV movie. But the surprise was, I bet I didn't spill more than 1 cup of liquid. Once the auger broke through to the tank I yanked the handle on the auger and closed the valve. No big mess. Keep in mind that I have the 3' auger...if you need a longer one to reach your tank then the potential spill could be larger.

We've had our tanks pumped many times by the honey wagon when we're at the Nascar races. They hook directly to the outlet and both tanks out in less than 5 minutes -- and we have big tanks! Never had a problem.

Sometimes the RV manufacturer leaves the plastic plug inside the tanks when the drill the hole for connecting the sewer pipes. I just might be that this time the plastic plug had aligned itself over the hole. Hope not. It is not a pleasant thing to remove it.