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Alden Miller · 07-12-2013, 05:38 AM

One issue we have had since aquiring our current Airstream is that the black water tank does not drain well. I usually end up repeatedly running a hose into the outside drain to fill it with more water and act as a snake to get things flowing. Not my favorite thing to do at the end of a trip.

I used the soap and ice cubes method to scrub the inside of the tank but still it wouldn't empty without assistance.

Finally I picked up an inspection camera that I can run through the plumbing and see what is going on, I was sure there was something stuck in the pipe that was causing this problem.

I found that the waste valve and pipe are clear but I have hardened "debris" on the bottom of the tank. This includes a pencil and what looks to be part of some eyeglasses.

Prior to us purchasing the trailer an older couple lived in it in Florida, it was up on jacks in permanent trailer park. I think that because of the static position and the heat from Florida that this allowed this to happen.

At least now I know what is going on inside the tank, I think the next steps will be to remove the toilet, install a lot of plastic sheeting, and get out the pressure washer. I think once the inside of the tank is clean and smooth I ought to be able to empty it easily again.

-Alden

jdalrymple · 07-12-2013, 05:43 AM

I would fill with water and soap then let it sit for several days, like a week.

A pressure washer may make more of a mess than you want to clean.

Regards,

JD

mandolindave · 07-12-2013, 07:42 AM

When I am hooked up at a camp ground, I leave the dump valve closed. When the tanks are close to being filled I open the dump valves. The large amount of rushing liquids move the solids. FILL the tank with clean water, and dump again. I NEVER get clumps or even visible pieces of TP because I am using the enzyme treatments, which doesn't call for a spotless black tank. It sounds like you have a dried TP build up, due to the PO leaving the dump valve open. Yeah, a long full tank soak with enzymes might work. I would try to wash out all of the blue treatments, because the blue stuff impedes the enzymes from doing their job. The enzyme method calls for some liquid AND some solids for the enzymes to " eat ". When not in use for a long time, or over the winter, you can still do the spotless tank method. You could also try waiting a few days after getting home, to dump. Allow the TP and " stuff" to dissolve. Google search Phred's Poop Sheet

Silver Goose · 07-12-2013, 08:15 AM

I'm on board with a good long soak also. I would try filling it about half way with water then add a cup of laundry detergent and a cup of Calgon water softener. Let it sit for several days, a week isn't too long, then take it for a ride through the neighborhood with many left and right turns to slosh things around, then fill it as much as practical and dump and then inspect to see if this made any progress. Repeat if necessary. It will also help after dumping to add and leave 1" or so of water to the BW tank to assist in dissolving anything that may have remained. We typically don't accumulate enough liquid in the tank through normal use to permit a complete flush when dumping so additional water helps. Enzyme treatments may also be beneficial in the long run.

Protagonist · 07-12-2013, 08:20 AM

Quote:

Originally Posted by jdalrymple

I would fill with water and soap then let it sit for several days, like a week.

A pressure washer may make more of a mess than you want to clean.

Regards,

JD

Use an enzyme treatment, double-strength, rather than soap. Soapy water will soften the solids, but not dissolve them. Enzyme digestion should dissolve the solids down to a slurry that should drain.

Alden Miller · 07-12-2013, 08:21 AM

I've done the long soak with the Calgon followed by ice cubes prior to travel and I still have a hardened mess.

I do follow Dave's method of filling the tank completely before flushing, then filling with water again before flushing. This trailer also has a setup that I can hook a hose to and rinse the tank but I think that the stuff that is hardened in there is almost in a fossilized state at this point.

I was given another suggestion of TSP and then Rid Ex which I might try before resorting to the pressure washer.

-Alden

dznf0g · 07-12-2013, 08:24 AM

I'm with Protag. RidEx now makes a liquid enzyme solution now....no grit. I would leave it in for weeks if in storage.

AirsDream · 07-12-2013, 09:18 AM

Probably a lot of buildup from prior owner ... will take time to "flush." I'd just keep doing the detergent or enzyme treatment plus occasional treatment with 25lb. of ice and driving around. It may take time, but I bet it will slowly do the trick.

blickcd · 07-28-2013, 06:38 AM

You are on the right track with the long soak, ice cubes, etc. You will eventually get it all out of there.

One other thing, it is possible that your holding tank vent is clogged with a mud dauber nest or some other similar obstruction. An easy test would be the next time you dump the black tank, have someone hold the flush valve on the toilet open and see if it drains noticeably faster.

The only way I know to clean that vent stack is to get on a ladder and blast water down the stack with a garden hose.

Alden Miller · 07-29-2013, 06:30 AM

I soaked the tank with 10 gallons of water and a box of TSP for two weeks. I went to drain the tank so I can rinse it fill it with water and add RidX to it. I opened the valve and nothing came out.

I got the inspection camera out and verified the valve was opening just fine so I went and bought a hand held drain snake to see if something was clogging the line even though the tank had been empty prior to the TSP soak. I can run the drain snake all the way in, it comes out wet but nothing comes out...

I checked the trailer level and it is reasonably level, not perfect but not enough that 10 gallons of liquid should stay in the holding tank.

Now I am totally confused, I wonder if the tank is sitting at an angle or something like that. I think next step will be to pull the toilet and see if I can get a better look inside the tank with a flashlight and mirror.

-Alden

TG Twinkie · 07-29-2013, 07:12 AM

Not to be a smart a##. But are you sure you are opening the black water valve and not the grey water valve?
How do you know which tank the snake is headed for? Because there is a sanitary Y somewhere that connects the grey and black water lines.

Alden Miller · 07-29-2013, 09:54 AM

Quote:

Originally Posted by TG Twinkie

Not to be a smart a##. But are you sure you are opening the black water valve and not the grey water valve?
How do you know which tank the snake is headed for? Because there is a sanitary Y somewhere that connects the grey and black water lines.

That's a fair question, opening the wrong valve is not beneath me...

If I am opening the correct valve, that is the tank that the snake is going into. Whichever valve is open is the one it is going into, otherwise it would just stop when it hits the valve.

Now I have something to check when I get home!

-Alden

Alden Miller · 07-30-2013, 05:53 AM

Well, TG Twinkie was right...

I have no excuse except maybe that the valves are reversed from our old trailer and I did not get down on my knees to check what was printed above the valve.

Now happily the 10 gallons of TSP and poop is out of the tank and it is now filled almost to the top with water and RidX which will stay and soak until we go out towards the end of September.

I sure hope I wasn't doing this all last season... Anyway, I labeled the valves a little higher up so I don't have to remember or get on my knees to see which one is which...

-Alden

Lance M · 07-30-2013, 07:10 AM

Alden,
Glad things seem to be working for you now. I wanted to let you know about this stuff I've used. It is called ByoGon. It is some sort of accelerant for the bacteria to consume the solids. The owner of the local SOB RV place claims that they use it with great results when the tank is completely plugged with solids. Dump six oz down the toilet, fill the black tank completely full and let it do its thing for two-three weeks. I recently treated my half full black tank this way and when I dumped the tank, the only thing that came out was clear water with a slight green hue. I was amazed. I hope you get it all cleaned out.

**jcanavera** · 07-30-2013, 07:38 AM

Quote:

Originally Posted by Alden Miller

Well, TG Twinkie was right...

-Alden

It's hard to break that habit. After 17 years of owning an SOB with the rear most pull handle being the black water, and now 12 years owning 2 Airstreams with the reverse, I still have to be careful to pull the correct handle. Thank goodness mine are labeled because I know that in some moment in one of my brain clouds I'd pull the wrong one. Not the biggest issue in the world when you are hooked up to a drain, but could be mighty embarrassing if I was sitting in the drive at home doing my grey water drain when I winterize or when I dewinterize.

Alden Miller · 07-31-2013, 11:47 AM

Quote:

Originally Posted by Top

Alden,
Glad things seem to be working for you now. I wanted to let you know about this stuff I've used. It is called ByoGon. It is some sort of accelerant for the bacteria to consume the solids. The owner of the local SOB RV place claims that they use it with great results when the tank is completely plugged with solids. Dump six oz down the toilet, fill the black tank completely full and let it do its thing for two-three weeks. I recently treated my half full black tank this way and when I dumped the tank, the only thing that came out was clear water with a slight green hue. I was amazed. I hope you get it all cleaned out.

Thanks! I have the tank filled with RidX now, I will keep this in mind if it doesn't come out clean at the end of September when I drain it.

-Alden

Alden Miller · 09-24-2013, 09:42 AM

Well, this last weekend was the test of the TSP and RidX. Everything came right out of the tank when I drained it once we got to the campground. I was happy at that, the inside of the tank looked clean also.

Yesterday when we were getting ready to leave I ended up spending 1 1/2 hours getting the tank to drain. I open the black water valve and nothing comes out. I ended up filling the tank with water over and over and opening the valve again, each time more solids came out (fun).

I think now that I have some sort of leak in the valve and or the tank. A slow leak but enough that the fluids leak out and leave a pile of solids.

So now I think I need to investigate the valve and or the tank. Does anyone have any tips on gaining access to one or both of these?

-Alden

mandolindave · 09-24-2013, 10:33 AM

Did you get the pencil and eyeglasses out? Could there be a clump of TP that is preventing you from closing the valve all of the way. I would fill the holding tanks with water, then monitor the drain. BUT the seals on those valve could be coated with gunk , or could have been worn out, dried out, or been ruined by the PO if they used Liquid Plumber or some other product Sorry, just trying to think of everything..

mandolindave · 09-24-2013, 10:46 AM

If it was me, I would know exactly what the problem was. It would be my eldest daughter, who for some reason is constantly dropping her cell phone in the toilet. Really....not all that funny. OK it's a little funny.
BUT since it is not me....it could be that the PO dropped a big wad of hundred dollar bills down the toilet.

Sorry, thought you might need some comic relief.

Alden Miller · 05-12-2014, 09:21 AM

Well it took a while before I got serious about tackling this. Last weekend I lifted the side of the trailer and gained access to the black water plumbing. I can't remember if I mentioned it but it looked like it had been worked on before so it was easy to get to. I had to drill out about 10 rivets and remove a dozen screws.

Once I had access I could see that it had a leak from the side of the valve. Once the valve was removed I could see that the valve would not shut all the way.

Attached are a couple of graphic photos (sorry can't be helped when working on this stuff). You can see the valve and the blown gasket causing the issues. I fixed this by getting a rebuild kit for the valve from ODRVM. A little careful work putting it back together and the last major repair on the trailer is complete!

-Alden