Drop commode seal question

wvcampers wrote:
Dometic says to put hot tap water in the bowl. I have done this twice and both time the seal started holding water again.

No doubt that may work but there is a point that the seal needs to removed, cleaned, lubricated and replaced. There may also be a time to simply replace the seal.

Dometic says to put hot tap water in the bowl. I have done this twice and both time the seal started holding water again.

Maintenance on the 300 series Dometic is very easy. Simply push down on the go pedal and pull out the rubber seal. Clean it up dry it and add a layer of Vaseline to bottom side of seal. With the ball closed push the seal in place. While seal is removed give the ball a good cleaning.

If a Dometic 300 series toilet, you don't need to remove the toilet to replace the rubber gasket but you probably don't need to replace it anyway. I had the same issue. I pushed down on the gasket all the way around and then cleaned it thoroughly with soap/water. Then I applied petroleum jelly (Vaseline) to the underside of the gasket (the side that comes in contact with the ball). That did the trick and I haven't had any further issue.

Wax rings are not recommended for RV toilet use. The normal vibrations while underway can spread the wax destroying the seal. The toilet manufacturers supply a closed cell foam seal made for the purpose. Without knowing the model of your toilet, it's difficult say what the flush ball seal replacement requires. On my Thetford Aqua Magic Style Plus porcelain bowl toilet, changing the ball seal takes about 15-20 minutes without lifting the entire toilet.

Which MODEL???

Some the seal can be removed/replaced w/o having to disassemble toilet (can be done w/o removing toilet)

Some you have to disassemble toilet. (Easier to do by removing toilet)


WAX Ring....
RV toilets use a 'foam gasket' between toilet and floor flange


So WHAT MODEL?



Many times seal/ball just need a thorough cleaning/lube job
Turn water off
Open Ball and using your hands (you can wash them afterwards!) go over the seal flexing it/feeling it/removing any mineral/stuff on it.
Then put some dish soap in your hand and scrub seal top/sides/bottom
Do same with ball ....clean it across top surface
Then rinse seal/ball clean
After rinsing all soap off lube up seal & ball with plumbers grease (OR Olive Oil)....no vaseline ---it is sticking & can attract crud