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Topic: Dometic Toilet doesn't hold water (Read 548 times) previous topic - next topic

Dometic Toilet doesn't hold water

About three or four years ago, I replaced the Microphor toilet in my coach with a Dometic toilet.  It has the round ball that rotates to flush and has rubber gaskets to make it water tight.

Well it no longer holds water and will leak down over a few hours.  Has any one else had this problem? If yes, what is the solution, other than buying a new toilet.

1998 U320 40'
2005 GMC Yukon
MC# 17609

Re: Dometic Toilet doesn't hold water

Reply #1 –
Hey Steve, try some CLR for a couple of hours, then. Then clean as best you can with an old tooth brush on the sealing surface. Don't get your tooth brushes mixed up😬👍
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country

Re: Dometic Toilet doesn't hold water

Reply #2 –
And if that doesn't work I'm thinkin you'll have to pull the top half and replace the rubber gasket.

 Replaced ours a few years ago with the dometic that you change the seal from the top.....  I love that.
Robert and Susan
 1995 36' 280 WTBI 8.3 3060r
 1200 watts on the roof, 720 Ah of lithium's
 Build # 4637. Motorcade # 17599
        FMCA  # 451505
        18  Wrangler JLUR

Re: Dometic Toilet doesn't hold water

Reply #3 –
Just had our toilet seal repaired while at FOT. Had to pull toilet and flip it to repair ball seal... holds water now. Dometic/Sealand toilet...could have done myself, but we were here getting other stuff done and only cost a couple hundred bucks...not much in the scheme of things😂😂
Keith and Dawn Hudson #18766
Current- 1999 U295 DFGE 40ft. - Build #5405
Coach Name: 4BUS4US
Previous- 2008 Nimbus CE338: 40th Anniversary Edition- Build #6486. 
Toad: 2021 Jeep Cherokee Trailhawk

 "I know something about a lot of things..a lot about something's..and everything about nothing "

Re: Dometic Toilet doesn't hold water

Reply #4 –
The rubber seal can be replaced from above. You should be able to see the black seal.
Hold the flush handle down and reach in and grab the seal and pull it off, then you have to make the new seal "snap" in or it will fall off and be in the black tank. I am sure the ball needs to be cleaned good also. A little silicon spray or even a thin film of vaseline will help for awhile. The seal dries out and gets brittle when there is no water in it.
I hope this helps
Ron
Ron Clark
Sherwood,Arkansas
1999 U 295 40 foot Build # 5550
2020 Jeep Gladiator
Motorcade # 18173
FMCA # F485593

Re: Dometic Toilet doesn't hold water

Reply #5 –
If you don't want to use CLR try vinegar, same process.  I use silicone plumbers grease to lube the seal on our Microphor toilet, works great. I have read someplace where vaseline (a petroleum product) can be hard on rubber parts.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Dometic Toilet doesn't hold water

Reply #6 –
I just went through this, it's pretty easy to do. There are 2 Sealand/Dometic rubber kits, with the circle and without. You can also check if you have a drain tube from the base. If you have the circle/drain tube, I have a new kit I'm going to sell, I bought the wrong one, otherwise Amazon has the other type. My post has photos of this as well as the why.

post Sealand toilet base

I'd also recommend going a step further and replacing the seal for the base, it comes with new bolts. Yours may be good if it was replaced a few years ago but if it wasn't it's a leak waiting to happen. LMK if you have any questions.
Jason
2000 U295 36' Non-slide  ISC350

Re: Dometic Toilet doesn't hold water

Reply #7 –
Thanks guys. I will try vinegar, because we have that.  I will move down the repair list if that doesn't work

This site is the best
1998 U320 40'
2005 GMC Yukon
MC# 17609

Re: Dometic Toilet doesn't hold water

Reply #8 –
Another "trick" is to clean the recess/rubber seal.

Take an old fashion wood clothes pin and cut it down to just narrower than the recess.  Use it to clean the recess.  All it takes is a small piece of toilet paper stuck in there to cause a leak down. Yes, be gentle.

And agree with lubing with silicone plumbers grease after cleaning.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Dometic Toilet doesn't hold water

Reply #9 –
You can hold the ball open and feel the underside of the seal with your finger, detecting any deposits that may allow leakage. If it is rough, empty the bowl and put a paper towel over the closed seal and add a bunch of vinegar OR use something like CLR Lime Away.  The paper towel will delay the seepage and let the calcium have time to dissolve.  Then, you can use toothbrush, fingernail, nylon scrubby sponge ... anything gentle enough not to scratch the seal but strong enough to rub off the deposits ... to get it smooth.  We used a very sticky silicone paste on our cleaned seal for lubrication.  May soak into the "rubber" a bit, but it keeps the seal soft for a good while and resists deposits building up.  Of course, replacing the seal is a good start, also, and then you can just clean regularly and maintain.

I know more about that everlasting commode than I EVER wanted to. 
Carol & Jeff Savournin
Usta have a '93 U225 36', Usta have a '95 U320 40', Usta have a '02 U320 40'
Usta have a 2006 Born Free, Usta have a 2011 Phoenix Cruiser
Usta have a 2012 Jeep Wrangler Unlimited 4dr
"Your time is limited, so don't waste it living someone else's life."  Steve Jobs

Re: Dometic Toilet doesn't hold water

Reply #10 –
I am at FOT now and had the same issue after I wintered in Yuma last year. Should have used my filtration and softener always and didn't. They had to remove and take it apart. Replaced all the seals after cleaning the calcium buildup off. Works great now.
Steven Green
1997 U-320

Re: Dometic Toilet doesn't hold water

Reply #11 –
I worked on cleaning the gasket today.  Wow,the gasket is black not light tan.  Yeah there was a lot of calcium.  I ended up using my finger nail to scrape it off.  The vinegar didn't begin to dissolve it.  It still leaks out, but slower than before. 

I will work on it again in a few days.  Based on previous discussion there should be a groove in the gasket for the edge of the ball valve to fit into.  I will work on that on the next "fix it" attempt
1998 U320 40'
2005 GMC Yukon
MC# 17609

Re: Dometic Toilet doesn't hold water

Reply #12 –
When my Dynast toilet was leaking I emptied the bowl and poured CLR into the
bowl and left it overnight. That fixed it.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport
 

Re: Dometic Toilet doesn't hold water

Reply #13 –
There are 2 grooves, one to keep it in place, this is the right front as your facing it. The larger hole is at the rear at the 12 o clock position. Do you have a tube coming from the rear of the base? This is not the spigot or water valve tubes. The hole at the spot is larger than the 5 o'clock stay. See my other post for pics of this larger hole. In my case, I had the hole in the base but the drain valve was plugged. Other thread states why.
Jason
2000 U295 36' Non-slide  ISC350