Black tank clog

rblake39 · 03-07-2016, 09:54 PM

We've had our Columbus fifth wheel for a couple of weeks now. I've emptied the black tank twice already no problem. Today I went to do it again. Pulled the lever and all was good. Pulled the gray, all good. Used the black tank flush and filled up the tank again. Pulled the lever, nothing. Black tanks not draining. I had to drive someone to the airport so didn't have time to check anything. Tomorrow's project. This is our first RV. What should I be checking for. We had my girlfriends kids here for a few days. Told them only toilet paper in the toilet. All in their upper 20's so don't think they flushed anything else down. So what could it be?

TURBS · 03-07-2016, 10:01 PM

Possibly not enough water when flushing.
Very common to not use enough.

Full bowl is the key!

I fill my bowl every time and do not have any problems!

2015 Columbus 320RS
2008 2500HD Duramax
2015 nights camped "34"

rblake39 · 03-07-2016, 10:05 PM

But the black tank emptied fine the first time I emptied it. Then when I went to flush it with the black tank flush it went to 2/3 full. Pulled the valve and it won't empty.

TURBS · 03-07-2016, 10:15 PM

First of all do not rely on the worthless tank sensors.
I'm guessing the black tank flush loosened up some "crap and tp" and plugged your outlet.
Now it's "possible" the valve isn't opening properly.

We've also seen a knockout from cutting the tank holes has been left behind in the tank and plugs the outlet as well.

Just giving you some ideas.

2015 Columbus 320RS
2008 2500HD Duramax
2015 nights camped "34"

rblake39 · 03-07-2016, 10:18 PM

So I'm guessing open it up and spray water with a hose and hope it loosens the clog?

TURBS · 03-07-2016, 10:34 PM

Or run a snake up the outlet [emoji51]

2015 Columbus 320RS
2008 2500HD Duramax
2015 nights camped "34"

VinceU · 03-07-2016, 10:37 PM

Quote:

Originally Posted by rblake39

We've had our Columbus fifth wheel for a couple of weeks now. I've emptied the black tank twice already no problem. Today I went to do it again. Pulled the lever and all was good. Pulled the gray, all good. Used the black tank flush and filled up the tank again. Pulled the lever, nothing. Black tanks not draining. I had to drive someone to the airport so didn't have time to check anything. Tomorrow's project. This is our first RV. What should I be checking for. We had my girlfriends kids here for a few days. Told them only toilet paper in the toilet. All in their upper 20's so don't think they flushed anything else down. So what could it be?

Could be the valve stem is stripped from the disc. Opening the valve may seem easier than before.

Too Tall · 03-07-2016, 10:47 PM

That could be very dangerous, ha. That may be your only alternative but IMO it should be your last for obvious reasons. I take it you looked in the toilet and verified the tank is really full? If so, it can only be one of two things, the valve stem has come loose from the gate and it is closed. I never heard of this. It would take a h_ll of a plug to hold back a full tank of fluid. But possible, especially if the wrong kind of toilet paper was used, I guess. you could fill the gray water and with the cap on open both and maybe back flush gray water into the black water. I'd be reluctant to do this with a hose as you could over pressure the line and blow it up if the valve is closed Stay with gravity, IMO.

fonzie · 03-08-2016, 06:00 AM

When you used your black tank flush did you hear water flowing? maybe the vacuum break check valve has been installed in reverse and there is no water flow, so reason why no water flowed out of black tank after the flush???

youroo · 03-08-2016, 06:32 AM

Quote:

Originally Posted by fonzie

When you used your black tank flush did you hear water flowing? maybe the vacuum break check valve has been installed in reverse and there is no water flow, so reason why no water flowed out of black tank after the flush???

I am here,Low Water/No Water in tank! Dont take this the Wrong way but 20 year old Kids

Just looking back in Time!

Youroo!!

nomad297 · 03-08-2016, 06:44 AM

Quote:

Originally Posted by VinceU

Could be the valve stem is stripped from the disc. Opening the valve may seem easier than before.

Usually when this happens, the whole handle and rod come out.

Bruce

youroo · 03-08-2016, 06:59 AM

Quote:

Originally Posted by nomad297

Usually when this happens, the whole handle and rod come out.

Bruce

Maybe Cable operated?

Youroo!!

**Mr. Dan** · 03-08-2016, 09:39 AM

Quote:

Originally Posted by fonzie

When you used your black tank flush did you hear water flowing? maybe the vacuum break check valve has been installed in reverse and there is no water flow, so reason why no water flowed out of black tank after the flush???

This is also my guess from a distance. We've had several reports of black tank flush not allowing any water through the vacuum break.

Sent (I think)

rblake39 · 03-08-2016, 10:46 AM

Took the drain hose off this morning. Looked down with a flashlight. Assuming the valve is silver it is not opening. Looks the same down there whether the lever is pulled open or pushed in to close. Gray doesn't drain either. I've been assured nothing but the Scott RV toilet paper we bought was flushed down. And we have had no problem with that for the last few weeks.

5picker · 03-08-2016, 11:09 AM

It sounds like the gate valve to the tank is not opening but it does seem odd that BOTH the black and grey would quit working at the same time. Especially, since you mentioned you emptied them yesterday during the first go round with no problem.

Run some water in the sink/shower with the grey valve open and see if water comes out the sewer port?

You said you seen something silver inside the sewer pipe. Most gate valve blades I've seen are black or white/translucent. Maybe there are metal bladed valves but I've not seen any?

If you get no water from either the grey side (or the black side) and you feel confidant the valves are connected to the pull handle/cable and working, I'd guess there is some kind of blockage in the pipe. A snake may be the only option.

I'd start with only the grey valve open when snaking.

whj77372 · 03-09-2016, 02:05 PM

I have a 2015 Wildcat 327ck fiver and there is a tag near the black tank flush and it states not to close the blank tank valve when using the black tank flush. Is that the case with the Flagstaffs?

OldCoot · 03-09-2016, 02:10 PM

Quote:

Originally Posted by TURBS

Possibly not enough water when flushing.
Very common to not use enough.
Full bowl is the key!
I fill my bowl every time and do not have any problems!

And this from a guy that made a BIG point in Goshen that HE NEVER DID #2 in his camper toilet. Ms. Amy said she did and he would empty it whether he liked it or not!

SO, do you or do you not do #2 in your camper toilet????

bob caldwell · 03-09-2016, 02:11 PM

They all say that.......if a person gets distracted, well..............

**Iwritecode** · 03-09-2016, 02:39 PM

Quote:

Originally Posted by whj77372

I have a 2015 Wildcat 327ck fiver and there is a tag near the black tank flush and it states not to close the blank tank valve when using the black tank flush. Is that the case with the Flagstaffs?

That's the case with any RV with a black tank flush. It's because it's easy to turn it on, get distracted with something else and then have a huge mess to clean up in the bathroom because the tank overflowed.

Rich5117 · 03-09-2016, 09:39 PM

Agree that the drain line after the valves is probably clogged. You can do a snake but be prepared to have someone shut off any open valves or you will have a real mess. You could also try to use a clear adapter with the flush connection and reverse flush the line, this may free up the clog. If you determine that it is a clog, I Would ultimately do the following get a clear adapter with the flush connection, unscrew the flush connector and run the snake up thru the opening this way you can leave the tanks open, to have that pressure help move the clog, once the clog lets loose put a rag over the connector hole and let the tanks empty.

To prevent this in the future make sure you keep several gallons of water in the black tank. This will prevent what is called the dreaded mound. This is when all the material that is flushed drops straight down the toilet and forms a mound of hard material. Keeping water in the tank lets the material move away from the bottom of the toilet.

Please let us know how you make out. Good luck.

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