Unblocking my black water tank

[Simoneau]

I've almost survived the first Massachusetts winter in my 2005 25' International CCD. I'm hooked up to a septic system, but my black water tank is no longer draining properly. It only drains very slowly and has backed up all the way into the toilet. My gray water tank is draining fine. My guess is that either the black water tank itself or its outflow pipe is blocked up. I've tried the mild enzyme-based septic tank treatments without success. My only thought is to try something more serious, Drano or the like, but the Airstream manual has made me paranoid about using something so corrosive in the system. Should I not worry about this? Is there something else I can try?

Thanks for your help!

[mistral blue]

What a crappy first post!

Sorry. Couldn't resist. Is snakin' it a possibility?

[RedSHED]

I'm definitely not an expert, but have you thought of hooking up and taking it for a drive? That sloshes things about and beats up the paper products a bit. Speaking of which, do you use RV single ply paper? I admit we use Cottonelle single ply paper because I'm cheap (RV paper is pricey in my opinion) but it has plugged up the toilet once already. RV single ply is much thinner and breaks up faster. I noticed our Target has it in our camping section. We may switch to that.
Mrs. RedSHED

[overlander63]

Do you let the black tank fill before draining it, or are you leaving the drain valve open all the time?

[lewster]

Originally Posted by overlander63

Do you let the black tank fill before draining it, or are you leaving the drain valve open all the time?

Matthew,

I have cleared 'more that one' black tank clog. Some are easy, most are difficult to impossible. It's important to know if you have been leaving the black tank valve open while connected or not.

It it HAS been open, then you have what's known as the 'black hills' residing in your tank. This is caused by insufficient water from each flush letting the liquids drain and the solids remain.

The accepted technique is to let the tank fill and then drain it in it's entirety, flushing it 1 or 2 times after that.

If you do indeed have Black Hills Syndrome, the only way I have found to clear this is to fill the tank with water, call a local septic service that has experience with RVs AND HAVE THE TANK PUMPED!

This is the only method I have used that works every time.

[2airishuman]

hi mathewsim and,

holy crap!

also welcome to the forums....

IF you are leaving the black tank always open to drain,

then you've got a poopy teepee growing right under the drop zone...

like a giant cherry mash!

if however you are correctly draining the black tank only when full and along with adequate fluids...

it could just be a paper plug...

before calling the suction tanker guys (a good idea) try this...

2 approaches to this issue,

into the mouth of the beast or at the exit...

wearing gloves and a mask or bandana and using a 10 foot section of old garden hose...

shove said hose down from above into the tank, push at least 8 feet in...

then rotate, agitate and other wise wiggle d' hose...

now open the black tank valve...any movement?

if not carry the hose outside and run'r up the drain valve with only the black tank open...

again agitate AND ya might want to wear high water boots for this step...

this will open up all but the most hardened coprolites...

please take some pics, we need a little humor this week...

and it seems i've misplaced my photos...

cheers
2air'

[Simoneau]

Wow! Thanks for all the speedy replies. Here are the answers to your questions.

Have people had good luck with a snake? I really don't have a good sense of how the plumbing is laid out. In my imagination, there's a pipe from the toilet, a big tank, and then a pipe out. It seems like it would be tough to get to the outflow pipe from the inside, if that is where the blockage is, but a snake would work if the blockage is "upstream". I'm a bit worried about snaking from the outside and releasing the 18 gallons because I don't know how fast I can get the sewerage pipe back on. Still, snaking from the inside would be an easy experiment. I'll definitely try it.

I think a drive is a great idea to "shake things up" in there, but the winterizing I needed to do on the pipes makes this a hassle and I was hoping to make it to the spring thaw without moving.

I've been using regular paper, but I'm switching to something more Airstream-friendly after this experience. Thanks for the tip about the single ply paper.

I leave the tank open all the time. This has worked fine except for in the coldest of winter, about two months ago, when it froze up and I had to hook up a heat cable to fix it. I may have Black Hills Syndrome. The tank is draining very slowly, so it would take some time (weeks?) for it to empty. I think this rules out the drain-and-fill trick. I may indeed have to call a septic service for this, but would love some other ideas to try first. I wish I could see what's going on in there.

Is the garden hose technique sounds promising. Is it just being used as a snake, or is the water flow critical? I really can't get any more fluid in there without creating a serious mess.

Thanks again to everyone for their replies!

[2airishuman]

ok your second post on #2....

your toilet sits directly over and on the tank...

it is straight down...

the garden hose is softer than a traditional sewer snake...

since the tank and fittings and valves and sewer lines are poly don't use a metal snake...

it will nick up things...

don't connect the hose to water, in fact cut off the end so there is no fittings to catch on things..

don't ask me how i know but the hose works...

cheers
2air'

and yer black tank should only be drained when full and especially if you are parked long term....

you may think 'always open' has worked 'fine' until now, but it takes time to build a cherry mash!

[lewster]

Matthew,

This may sound a little defeatist, but FWIW, you're wasting your time trying to undo the 'Black Hills'. I have tried and discarded just about every technique, gadget and rumor out there to try to clear black tank blockages caused by an open black tank valve.

You are sure welcome to try them, but if you really want to save your time and ultimately your $$$$$.........CALL THE SEPTIC SERVICE!!

The huge power of the vacuums on those trucks is the only thing that will get you cleaned out. And BTW, have them do it 2 or 3 times with you filling the tank with water each time. IT WORKS!

[Simoneau]

2airishuman, I followed your instructions. No luck from above, no matter how much I thrashed the hose around. I don't think the drain is directly below the toilet in my tank. I poked around the bottom with a headless plunger and couldn't feel the outflow pipe. Anyway, I took the hose outside and removed my sewer hookup. The black water pipe drops vertically out of the bottom of the Airstream, turns 90 degrees to the horizontal, and then runs about two feet before it connects to the grey water pipe and the the sewer hookup. I could push the hose up the pipe only about a foot and a half before running into the blockage. After about 10 minutes of poking, I felt it begin to move. I quickly withdrew the hose and there was a moment of panic when it snagged and I realized I couldn't close the valve with it in the way. Fortunately, the 18 gallons of black water was held back for a few more critical seconds and I was able to get the hose out and the valve closed. After re-attaching the sewer pipe, I opened the valve and the tank drained successfully! I flushed it a few more times and everything seems to be operational again.

Thanks again to 2airishuman and everyone else for their replies!

[overlander63]

Originally Posted by matthewsim

I opened the valve and the tank drained successfully! I flushed it a few more times and everything seems to be operational again.

Thanks again to 2airishuman and everyone else for their replies!

Now, for the big question:
Have you learned from this experience, Grasshopper?

[steelbird312]

Be prepared to get dirty.
Close the black water drain valve.
Pour three 5 gallon buckets of water into the black tank.
Let it sit for several hours.
take the slinky hose loose from the ground drain, leaving it attached to the trailer.
Pull the opening up about waist high.
While holding it at that level, have someone pour a couple to 3 gallons of water into the slinky hose.
Stuff the end of the hose with plastic Walmart bags.
Now, this is the trick- I will try my best to describe it.
Hold the hose down close to the ground , and then raise it as high as possible, as quickly as possible, holding the hose only at the end next to the ground drain connector. This will cause the 2 to 3 gallons of water to go rushing back into the black water tank with the pressure of about 18 lbs rushing against what is most likely clogged up paper in the black PVC piping.
You may need to do this a number of times. I would do that motion at least a dozen times, before remmoving the bag plug, and trying to see if the tank will indeed drain.
This will work except in the most seriously packed cases. Sometimes, it takes 2 dozen sloshes (back and forth water action against the clog) to break it loose, however, it works. Believe me, from experience, I can say it works.
Credit for this solution goes to the late Dick Norsworthy and the ever present Ben Millard, both WBCCI members in the GA unit.
Good luck.
If you have questions, give me a call

Best of all- its FREE!!!!!!.
Jerry 404-376-5937

[Darol Ingalls]

Now, after the spring thaw and you hit the road again, drain your tank as well as possible, add a couple gallons of cold water and a couple bags of ice cubes from the store. Drive over something else than smooth freeway for a few miles (until the ice melts) then drain and flush with clean water. Should break up any remnants left over from the clog. Darol

[2airishuman]

hi mathewsim...

wait no pictures....oh man

good to read about your movement!

now that flow is re established,

i suggest running about 3 full tanks of water through the black tank system...

then after the 3rd tank, close the valve again and add an enzymatic and bacteria to the tank.

Wastewater Treatment RoeTech · manufacturers of wastewater treatment products

a product like roebic k-37 or k-57 and a few days with the valve closed, allows the bacteria to eat-n-digest...

Bacterial Treatments by Roebic Laboratories, Inc. - 203-795-1283

it would also be useful to fill and drain the grey tank 2-3 times...

very likely, there are small 'mounds' in both drain pipes, so full flushing is useful...

the bags of ice (as darol suggests) are a great way to break up dry crud and stuck debris on the tank walls...

once you are back on the road, and travel is very good for regularity too!

cheers
2air'

[dwightdi]

Next year do not leave the tank valve open all the time. Discharge the tank only when it has built up sufficient volume to keep the stuff in suspension. You also might try to use one of those 90 degree bend flusher extensions on the garden hose once in a while (when you have a couple nice days during the winter) to stir up the tank before you drain it.

[Steve & Susan]

Hello -

We have a 2005 28' CCD and foound some construction debris that was jamming up our black water tank. Here are my two cents...

Go to the auto parts store and get yourself an inspection mirror - telescoping.
Then get a powerful flashlight - 3 D Maglite.

Put the mirror in the toilet with the valve open and shine the light either down the toliet hole or in through the black water dump valve. This should show you exactly what your problem is and then you can pick the appropriate solution from all of the above posts.

One thing we learned VERY quickly from tent camping, taking my Scout Troop camping, backpacking and now Streaming - a bad experience in the loo will ruin your trip. Also, you'll develop a tolerance for all things connected with poo!

Best of Luck!

[Chuck]

glad to see you flushed out the problem....

so, where are you parked? I see your profile says "Boston"...not many campgrounds in the city, at least, of which I am aware.

We're having our first wbcci rally of the season in just 3 weeks at Salisbury beach. come on up and see us! we're a fun group.

[Simoneau]

overlander63, I learned about the hazards of the black hills and how to avoid them.

steelbird312, your technique sounds a bit dangerous, but I bet it works. I'll keep this in my bag-of-tricks for next time.

Darol and 2airishuman, thanks for the after-care suggestions.

Thanks again everyone!

[Simoneau]

Sorry, I'm just now noticing the second page of replies. Thanks for the additional info dwightdi and szy8xj.

Chuck, it seems I'm still in some denial that I'm not living in downtown Boston anymore. I'm living in a trailer park in Westborough for the winter, which is almost an hour west of Boston. I'd like to find a place closer to the city and preferably a bit more scenic for the summer. I won't be able to make the Salisbury rally, but I'll definitely be hitting one soon.

[dieterdog]

2 air,, too funny!!!!!! have found that a small amount of dishwashing liquid and a bag of ice ,, and pouring dishwater into the commode helps to maintain regularity also,,, keeping a good mix of liquids and solids keeps the slinky smilin,,,, donna