Forum Discussion

zach477's avatar
zach477
Explorer
Jul 05, 2016

I finally figured it out!

I think I finally figured out why I have been getting black tank oder. It seems to go away when I plug the hole that the flush water comes out of. Now, I have been told that the "newer" Thetford Aqua Magic toilets do not have an overflow drain, and I can't visibly see one. My RV is from 08.

I don't see an overflow drain, and it certainly doesn't act like there is one when I purposefully overfill it. If that's the case, why is there odor coming from there?

I have noticed that after letting go of the flush handle the water stops running like it should, BUT about a second later there is a little "burp" and a small amount of extra water trickles out. It's not the kind of burp you get from the drain when your black tank is full. It's a burp that comes from the flush hole...if that's what you call it. :/
Class A
  • dave17352's avatar
    dave17352
    Explorer
    Jul 06, 2016
    Sounds like a bad seal at the flange. I had one of those toilets with the overflow drain that leaked sewer gas it was awful! My present truck camper appears to have the same overflow but does not leak gas. If it does I will replace it no questions asked. But your if your present toilet has no overflow drain then it has to becoming from the flange or a leak in the vent system someplace. Does your flapper hold water. If it doesn't you will have the same problem.
  • zach477's avatar
    zach477
    Explorer
    Jul 06, 2016
    dave17352 wrote:
    Sounds like a bad seal at the flange. I had one of those toilets with the overflow drain that leaked sewer gas it was awful! My present truck camper appears to have the same overflow but does not leak gas. If it does I will replace it no questions asked. But your if your present toilet has no overflow drain then it has to becoming from the flange or a leak in the vent system someplace. Does your flapper hold water. If it doesn't you will have the same problem.


    I have replaced the flange, and the bowl holds water. I have a previous thread that discusses all the possible causes. Now I have discovered that I can make it go away by just plugging the hole where the water comes out. That's where the problem is.
  • braindead0's avatar
    braindead0
    Explorer
    Jul 06, 2016
    How in the world would the water inlet be getting fumes from your black tank? That sounds very odd.. and perhaps a bit disturbing (fresh water meeting up with black?)
  • dave17352's avatar
    dave17352
    Explorer
    Jul 06, 2016
    braindead0 wrote:
    How in the world would the water inlet be getting fumes from your black tank? That sounds very odd.. and perhaps a bit disturbing (fresh water meeting up with black?)


    Yes I agree with this. Totally!!something screwy going on around here!
  • zach477's avatar
    zach477
    Explorer
    Jul 06, 2016
    braindead0 wrote:
    How in the world would the water inlet be getting fumes from your black tank? That sounds very odd.. and perhaps a bit disturbing (fresh water meeting up with black?)


    That's why I'm asking! Haha.
  • dougrainer's avatar
    dougrainer
    Nomad
    Jul 06, 2016
    zach477 wrote:
    braindead0 wrote:
    How in the world would the water inlet be getting fumes from your black tank? That sounds very odd.. and perhaps a bit disturbing (fresh water meeting up with black?)


    That's why I'm asking! Haha.


    There are no overflow holes. I would take the complete toilet out and look at the inside cavity. There can be a lot of sewage buildup and you need to use gloves and bleach and a water hose to clean out that cavity. Once you pull the toilet and look up from the bottom, you will see what I am talking about. Doug
  • braindead0's avatar
    braindead0
    Explorer
    Jul 06, 2016
    zach477 wrote:
    braindead0 wrote:
    How in the world would the water inlet be getting fumes from your black tank? That sounds very odd.. and perhaps a bit disturbing (fresh water meeting up with black?)


    That's why I'm asking! Haha.
    However the subject of this post is "I finally figured it out!" which isn't a question.
  • zach477's avatar
    zach477
    Explorer
    Jul 06, 2016
    braindead0 wrote:
    zach477 wrote:
    braindead0 wrote:
    How in the world would the water inlet be getting fumes from your black tank? That sounds very odd.. and perhaps a bit disturbing (fresh water meeting up with black?)


    That's why I'm asking! Haha.
    However the subject of this post is "I finally figured it out!" which isn't a question.


    I figured out WHERE it's coming from, but not WHY. There were multiple questions in my original post. Now you're just being difficult. :P
  • braindead0's avatar
    braindead0
    Explorer
    Jul 06, 2016
    Point is you might want to change the topic (edit first post, should be able to change topic) to something that's more likely to result in good feedback. perhaps "Help - Black tank odor from toilet fresh water inlet"
  • norwestie's avatar
    norwestie
    Explorer
    Jul 06, 2016
    If your coach has a washer/dryer and you don't use it much, the p-trap may be empty of water, allowing fumes into the interior of the coach. Try running a rinse only cycle with some towels and see if that makes a difference.

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