Forum Discussion

Fordy1's avatar
Fordy1
Explorer
Aug 11, 2015

Toilet Bowl Won't Seal

I have a Dometic 310 in my 2010 Cougar, bought new in 2010, after the first 6 outings the bowl would not hold water, took it to the dealer at the end of that first season and they replaced the seal, since then I have gone through three more. I have cleaned the bowl and flush gate, tried Vaseline and/or plumbers grease each time. The last one I replaced only lasted two outings. Questions 1) is there an adjustment for how tight the flush gate mates to the rubber seal, 2) is it time for a new toilet? 3) is there a better toilet?
Seeking Advice
  • rickhise's avatar
    rickhise
    Explorer
    Aug 12, 2015
    Those seals have a right side up

    But like the previous poster said you have a poorly molded plastic shi--ter,
    Replace it

    Those units as u know already are two nuts an replace a hose clamp simple list fix,

    If it's from an upside down seal your water should slowly drain. An give u enough time to have water In the bowl. Useable but I'm sure your thinking of the extra holding tank water your using. Let's us know how it turns out
  • rode2nowhere's avatar
    rode2nowhere
    Explorer
    Aug 12, 2015
    I have a dometic 310 also, it has a hairline crack in the flapper thing. And of course dometic says its not a replaceable part
  • jwmII's avatar
    jwmII
    Explorer
    Aug 11, 2015
    Ron3rd wrote:
    If someone's sticking a toilet brush down past the valve, it's easy to dislodge the seal, the wife does it all the time on our 310 and the fix is easy. There is a procedure from Thetford that calls for re-seating the seal and filling the boil with nearly boiling water and let it sit for a while. Maybe somebody can post this procedure as I can't get to it right now. Works every time.







    Does Dometic Have the Thetford line. It was my understanding that the Thetford line was part of NORCOLD. If so the Hot water fix might not be the thing to do on a DOMETIC product.
  • Ron3rd's avatar
    Ron3rd
    Explorer III
    Aug 11, 2015
    If someone's sticking a toilet brush down past the valve, it's easy to dislodge the seal, the wife does it all the time on our 310 and the fix is easy. There is a procedure from Thetford that calls for re-seating the seal and filling the boil with nearly boiling water and let it sit for a while. Maybe somebody can post this procedure as I can't get to it right now. Works every time.
  • therink's avatar
    therink
    Explorer
    Aug 11, 2015
    I've had this problem numerous times over the past few years (every 3 months or so). When the bowl doesn't hold water anymore, I put on a latex glove, grab a good dab of vaseline and work it around the upper and lower edge of the rubber seal. I have found that mineral deposits and other nastys coat the seal surfaces over time causing voids. It just needs to be cleaned real good and lubed. The works well for me.
    It isn't for the faint of heart but give it a try. Btw, turn off water first and don't have the bath fan on.
  • BTPO1's avatar
    BTPO1
    Explorer
    Aug 11, 2015
    lovetotow wrote:
    My in laws have a 2008 cougar, they had to get in the slot where the seal fits into with toothpicks to clean small pieces of toilet paper that gets chopped off when the bladder closes too fast


    X2, but I don't know about using toothpicks. I use a piece of a coat hanger with the end bent into an "L" shape to clean out the particles that are stuck. I also leave water in the bowl to keep the seal moist. Some have told me not to do that but, if you don't the seal will dry out and will not hold water. JMO
  • lovetotow's avatar
    lovetotow
    Explorer
    Aug 11, 2015
    My in laws have a 2008 cougar, they had to get in the slot where the seal fits into with toothpicks to clean small pieces of toilet paper that gets chopped off when the bladder closes too fast
  • 100ton's avatar
    100ton
    Explorer
    Aug 11, 2015
    I had good results with this issue by removing the water and adding a cup or two of vegetable oil and letting it set for a while. Although, since you have already tried replacing the seal, this may not be the solution in your case. Let us know once you find the remedy.
  • midnightsadie's avatar
    midnightsadie
    Explorer II
    Aug 11, 2015
    its time to throw it out,, sounds like its a defect in the plastic mold . I,d quit fooling with it, and buy the wife a nice birthday present.. A NEW THRONE.

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