Forum Discussion

psa0298's avatar
psa0298
Explorer
May 20, 2014

Leaking toilet blade seal fix

I replaced all the seals in my Thetford toilet about 4 years....it cost about $60...rediculous. Last fall the blade seal started slowly leaking again. I tried cleaning it, scrubbing the groves with a brush, etc without success. I figured they should last a little longer. I decided to order an entirely new mechanism service package(another $60 from amazon).....4-6 weeks delivery time. When I was dewinterizing and cleaning I decided to throw a littlte CLR in the bowl and it has since stopped leaking. There must have been some sort of mineral buildup on the blade that the CLR has removed. I'm not sure if anyone else has tried this but it might be worth a shot before replcing you seals.

Moved to Tech Issues forum from DIY.

  • ryanw821's avatar
    ryanw821
    Explorer
    May 20, 2014
    CLR is some great stuff, we have such hard water here you can drink it with a fork, so we use CLR in dang near everything in our stick and brick, sinks, dishwasher, toilet, tub, you name it. :)
  • remdog_1's avatar
    remdog_1
    Explorer
    May 20, 2014
    Rub some vegetable oil on rubber seal once a year, keeps it from drying out
  • Old-Biscuit's avatar
    Old-Biscuit
    Explorer III
    May 20, 2014
    YEP....when cleaning seal gotta scrub blade/ball valve.

    CLR works well. Just be sure to not let CLR sit too long and rinse seal then lube it with veg. oil/olive oil/plumbers grease....not vasoline/petroleum.

    When I winterize I poor some oil in bowl for the winter.
  • bob_nestor's avatar
    bob_nestor
    Explorer III
    May 20, 2014
    $60 for the seal kit? I got TWO kits for mine for under $30 by shopping on-line.
  • ScottG's avatar
    ScottG
    Nomad
    May 20, 2014
    psa0298 wrote:
    Won't oil cause the seal to deform?


    Not vegetable oil.
    Works good on dump valves too.
  • B_O__Plenty's avatar
    B_O__Plenty
    Explorer II
    May 20, 2014
    Think about this..adding oil to the toilet will only allow the oil to float on the water above the seal, doing nothing. Go around the edge with a toilet brush while holding the toilet open. Then close the flap, and with your fingers, press down on the rubber seal all the way around to reseat the seal. After all that..pour a pan of boiling hot water into the bowl and let it sit until cool. Problem will be fixed. This info comes right out of the Dometic manual. This has worked for me EVERY time!

    B.O.
  • kaz442's avatar
    kaz442
    Explorer
    May 21, 2014
    B.O. Plenty wrote:
    Think about this..adding oil to the toilet will only allow the oil to float on the water above the seal, doing nothing. Go around the edge with a toilet brush while holding the toilet open. Then close the flap, and with your fingers, press down on the rubber seal all the way around to reseat the seal. After all that..pour a pan of boiling hot water into the bowl and let it sit until cool. Problem will be fixed. This info comes right out of the Dometic manual. This has worked for me EVERY time!

    B.O.


    He stated when winterizing. You would have the water off then flush so there's no water in bowl.

    I just fixed mine by cleaning and spraying some silicone lube in about 1/4" (without water) and let it sit overnight.

    JKaz
  • steveh27's avatar
    steveh27
    Explorer
    May 21, 2014
    I have the recirculating thetford. I am getting ready to replace mine for the 3rd time. Seems they last 40-50 openings and closings over 4 years before the blade catches the seal edge & bends it back. Seems like a poor design. And in my B I have to get under the van to unbolt the through floor bolts to remove the toilet. A 2 day job & too much effort. I can remove the top easily. In the future I'll do this after emptying and directly apply some lubricant several times a year. Thetford has their own product.

    I will try that hot water fix soon first. Hope the tip works.
  • Dave_H_M's avatar
    Dave_H_M
    Explorer II
    May 21, 2014
    kaz, do you mean that you sprayed the silicone in there until it puddled in the bottom of the toilet? Right now i am using plumbers grease (silicone grease) on mine.

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