Toilet bubbles when flushed

[Moose509]

Have a 2011 Forest River Palamino Sabre 31RETS, the issue is when the toilet is flushed, it bubbles first and then goes down. It bubbles like it has air lock or pressure in the black tank. Is there a vent valve in system that might be stopped up.
Where do I start??

All suggestions will be greatly appreciated.

[rana]

If you're sure you aren't full it could be that your exhaust tube is plugged. You'll have to go up top and check for any obstructions. If you have a bend in your inlet leading from the toilet to your black tank, it's also possible that you have a partial obstruction.

I would check the exhaust vent first though. It's much easier to diagnose and clear.

[merrykalia]

Mine does that when it gets close to being full, but it did it once before and I knew it had just been emptied. I ended up getting a hose and blowing water down there there at a pretty good pace and cleared out whatever obstruction there was in there. It has worked fine since then.

[OldCoot]

Could be the vent pipe has slide down in the tank. Might pull the cap off and measure down to the bottom of the tank and then hook the side of the pipe and see the difference. Should be at least 5" or 6" difference. If not, pull the pipe up and secure it with a pop rivet or screw thru the roof flange or just drill a hole completely thru the pipe and put a pin/bolt thru it.

[dannyabear]

I had this problem on a previous 5th and one of my brothers had same problem a week ago..The culprit-the DW using too much tp... Bring a hose inside and run it theu toilet to wash out the blockage..My TT doesn't have this problem because its a straight shot down into the tank. You may need to feed several feet of the hose thru the toilet.

[TURBS]

Sabre black tank is not a straight "shot" from toilet, it has two elbows before going into black tank.
I'd guess partial blockage.
Use plenty of water when flushing.
I'd do as suggested and use a water hose to run water down toilet pipe.

TURBS
08 duramax tuned n modded, 32bhok Sabre
2015 camping "4 nights"

[Fred H.]

Mine did the same thing the very first time I took the RV out. Found that I cannot wait until the "level lights" show full before dumping. It also happened to my friend with his RV.
Conclusion is that the vent pipe is protruding into the tank several inches. When the level reaches that point the toilet will blow bubbles when flushing. Don't let your tank get more than 3/4 full before dumping.

I also agree with others about giving the tank a good flush via the vent, then through the toilet using a hose.

[Grn_Mtns]

We use a stick to knock solids down Toilet sleeve into tank. I may have pipe protruding into the black tank too far. Happens too often GRRRRRRR.
Good Luck!

[Ken Halloran]

Had the same problem. Tank not getting enuf water. I put 5 gallons (5 bowls) in tank after clean dump - 2 oz. of Calgon water softener (keeps tank sides slippery) - 1 capful of liquid laundry detergent (slippery and cleans up) and the chemicals. Haven't had a problem since (2 years - lotsa dumps)- it's just basic tank maintenance - especially if you don't have a straight drop into the tank - mine is a subtle curve pipe to the tank - stuff would accumulate in the pipe at the point it entered the tank. Good luck. Ken

[DAISY BOYKIN]

After dumping black tank & flushing it thoroughly. I add approximately five
gallons of water to black tank so it will not be dry. I then add three "PODS"
for dish washer to the bowl with about a gallon of water along with the recommended "POD" of chemical (THE ORANGE TYPE) to let it dissolve.
After letting the dishwasher "PODS" and orange Chemical for the black tank dissolve, I then dump the toilet bowl into the black tank.

I look at it this way, The dishwasher "PODS" clean the tank along with "NO-SPOT" chemical on the pods cleans the tank and no clinging of "STUFF"
(brown gold fish as we said in the plumbing business in the navy) is stuck to black tank.
After almost four years, no black tank problems!

[j free]

my Columbus did the same thing when I was dry camping and the black tank seems to be narrow to other tanks that I have had. the TP was building a mountain under the port and prevented the product from exiting evenly.

[mike1m]

I have had the same problem in my Windajammer. It has happened about half a dozen times and I have advised the better half to use less TP. Since then it has been better. I usually use a stick to move the mound of TP that is stuck at the bottom of the pipe. I recently switched out toilets (for other reasons) and noticed where it drops into the black water tank the gap between the top of the tank and bottom is very small and seems like a poor design. Too much coming down at once and it cant float to the other end of the black water tank easily.