Tank level indicators were all showing crazy amounts. Drained and flushed tank with built in rinser. Closed valve and let rinser wash out and fill tank. Drained.. Did this several times until water was running pure. One more time for good measure...;) I got distracted setting up the Grandkids fishing poles and next thing I know I had water coming out of the vent pipe. It was clear but I had some water on the floor around the toilet. Opened valve but without the air vent it would not drain. Flushed toilet and it exploded in my face.:o Cleaned up water while tank drained.Question is...did I do any damage to anything by letting the tank overfill and flow out the air vent?Sad thing is..tank level indicator still not correct!

Wipe your face off and go camping :)Probably didn't damage anything assuming there is no water damage to the floor. I wouldn't worry about it.

My children borrowed my MH for a fun week last year. Daughter called me to check the hookups, and said there was no water pressure in sink.???? While talking about it she screamed the toilet was overflowing!!!! Yup, she hooked the water up to the black flush line. No damage other than to her pride. They still borrow the MH regularly.Happy Trails.

I've done a very similar thing. Just be thankful it was after several rinse cycles. Just make sure any wet spots are cleaned up and allowed to dry.

And this is a prime example of why I don't "flush" my tank. I've seen this happen way too many times on here. I just don't need a chocolate river flowing through or over my RV. When I look down the bomb bay door and see the offending items close to the bomb bay door opening I know it's time to dump the dumper. :B

Black tank overflow !!! | Good Sam Community

wa8yxm
Explorer III
Sep 29, 2014
One thing to do is go topside and remove the "Hat" from that vent pipe.

On my coach the pipe you see is about what, 2" (Standard size) the pipe itself is like 1 1/2 inch inside that pipe with lots of room for liquid to drain back down inside the wall if you pull a Robin Williams...

Of course, this rig, won't push water that high, overflows...elsewhere,,,first.
Rvpapa
Explorer
Sep 29, 2014
To the O/P,
If you don't post pics it DID NOT HAPPEN
Please recreate problem and post full video. If using U tube audio would be ok. :B
Art.
Drew_A_
Explorer
Sep 29, 2014
I had this happen years ago and the black tank dislodged from the supports due to the bulging that happened while it was overfilled.

I didn't notice right away, and the tank eventially cracked where the outlet pipe exits.

You might want to inspect it from underneath.

-Drew
kroghville
Explorer
Sep 28, 2014
Tank level indicators are known for being un reliable. I basically ignore them and dump once a week. With just DW and me using the rig we have learned that we can go at least that long without filling any of the tanks. The fresh water tank level indicator is the only one I would trust. If the tank gets overfilled it just runs out the over flow onto the ground. No damage done.
Harvey51
Explorer
Sep 28, 2014
I hate to admit it but we had the reverse experience last trip. After four days boon docking we still had lots of water in the freshwater tank so I didn't even worry about the black tank filling up. No dump site nearby. One more day. Noticed a bit of sewer smell outside on the driver.s side, thought it might be the neighbour but did put some odour control stuff in the toilet in case it was us. Headed for home. After an hour of driving and a couple more flushes, we stopped at an art gallery. I did the walk around and noticed the much stronger smell was with us . . . and a brown streak on the side downwind from the blank tank flush inlet. Definitely time for a dump!!
Old-Biscuit
Explorer III
Sep 26, 2014
austinjenna wrote:
OR, Yes I did and this solved it for good. Sometimes stuff gets stuck down there. Reach your arm down the hole as far as you can. When down to the max feel around for anything chunky. Grab it and squeeze it between your fingers until it gets smaller then dump some water in it (After you pull your arm out of coarse}. Do this once a month for regular maintenance. Wash your hands before cooking. I do have a self help video available. Hope this helps.

Umm...yah...that sounds like a good plan.... or maybe use a flusher and not stick your arm down a toilet to squeeze poo every month, but hey to each his own I guess.

That's 352s cure for any/all black tank issues...even overfilling one by accident.
austinjenna
Explorer
Sep 26, 2014
OR, Yes I did and this solved it for good. Sometimes stuff gets stuck down there. Reach your arm down the hole as far as you can. When down to the max feel around for anything chunky. Grab it and squeeze it between your fingers until it gets smaller then dump some water in it (After you pull your arm out of coarse}. Do this once a month for regular maintenance. Wash your hands before cooking. I do have a self help video available. Hope this helps.

Umm...yah...that sounds like a good plan.... or maybe use a flusher and not stick your arm down a toilet to squeeze poo every month, but hey to each his own I guess.
352
Explorer
Sep 25, 2014
OR, Yes I did and this solved it for good. Sometimes stuff gets stuck down there. Reach your arm down the hole as far as you can. When down to the max feel around for anything chunky. Grab it and squeeze it between your fingers until it gets smaller then dump some water in it (After you pull your arm out of coarse}. Do this once a month for regular maintenance. Wash your hands before cooking. I do have a self help video available. Hope this helps.
ScottG
Nomad
Sep 25, 2014
To answer your actual question; no, it wont hurt anything for liquid to up the vent stack.
Old-Biscuit
Explorer III
Sep 25, 2014
Concerns when a tank has been overfilled like that....

Tank may have bulged which can cause splits, may have dislodged vent and/or toilet dump line connections at tank (some are glued to tank some use a grommet/gasket), may have weaken/loosened support straps.

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