Dometic series 310 flush ball problem

[carlson]

Just wondering if anyone has had a problem with their Dometic series 310 toilet and the flush ball not sealing against the seal? All of a sudden the flush ball does not seem to return tight enough against the rubber seal to keep water in the bowl of my toilet.I've taken the seal out and cleaned it along with the flush ball and it seems like maybe the spring(s) do not have enough tension to completely close the flush ball. Contacted Dometic and customer service advised to clean the seal and flush ball and if that didn't work, maybe the spring(s) were the problem. The camper/toilet are 8 years old so maybe springs have lost tension over the years? Of course that model toilet supposedly has no repair parts for springs/flush ball. Before spending $200.00+ on a new toilet, thought maybe someone had some ideas. I am going to try and get at springs to spray with silicone to see if maybe that will help. Thank you.

[cboss]

Try a little Vaseline on the seal and track then let the seal slam shut (just move your foot off the pedal to the side).
Hope this helps.

[Rhumblefish]

Actually, this is a known issue, and identified in the toilet manual (like toilets come with manuals) (pro tip: they DO!).

The seal gets a little lazy. You can replace them (the gaskets themselves are super cheap, like 2 for $9), or you can 'refresh' them by pulling them out, soaking them in hot water for a while, then reinstalling. The manual's procedure is to push down on the seal a little bit IN place (ball opened), then closing ball and adding hot water to the bowl. You decide what will work for you.

There's some other things to try, including silicone or seal conditioner, but the hot water trick is mentioned in the manual... video below is more exhaustive, I'd give the hot water trick a try.

Hope this helps.

https://www.youtube.com/watch?v=fGJh09MyLoo

[carlson]

Thanks for the rapid responses. I did read the owners manual for the toilet and did see the information about cleaning which I tried and even removed the seal, cleaned and re-tried.
Thanks for the video, I will go through the steps once again and see if anything changes, if not I'll try a new seal and see what happens. It just seems the flush ball is not returning to a position to seal.

[TitanMike]

I just finished servicing my 310. The old seal just had zero lube on the side that contacts ymthe ball.

Going forward I'm going to periodically turn off water (pump off, no city water connected) and with ball valve fully open just reach through and clean bottom of seal with wet paoer towell. Then apply a coating of silicone faucet stem grease to both seal and top of ball valve.

My toilet now retains water in the bowl and was still there a week after I returned from my last trip.

Yes, seals are cheap and I have had one in my kit since I bought my trailer but some easy maintenance can put off the task of replacing it for a long time.

[carlson]

Thanks for the reply. Ironically, the problem with the flush ball started right after I applied some plumbers silicone grease to the flush ball seal as I thought it may need some lubrication after 8 years.

[NMWildcat]

Originally Posted by carlson

Thanks for the reply. Ironically, the problem with the flush ball started right after I applied some plumbers silicone grease to the flush ball seal as I thought it may need some lubrication after 8 years.

I just replaced my seal after 10 years. Before that, I would use plumbers grease occasionally to maintain the seal so the toilet would hold water.
A caution with plumbers grease; use sparingly! Too much seems to cause as many problems as too dry.
Too much grease seems to attract other things like hair, bits of tp, etc that will stick to the ball/seal and cause it not to seal.
Our toilet ball doesn't always return back far enough if I don't let it snap back. So don't be afraid to let the pedal snap back instead of easing it back up

[bubbles]

The flush "ball" is attached (free floating) on the right side (looking from front of toilet) to the actuator and sometimes that side can slip out of its position (slot). It will typically look low on the right side when closed. It just needs to be put back in the slot (hole) with ball open on the side of the toilet. Check left also. But maybe it's not the issue.

[wayne Dwyer]

I have to replace the seals twice a year, a very poor design

[markb422]

Could the seal be installed upside down? I believe the seal has a flat surface on one side and the other side is stepped or recessed. The flat surface should be facing down. I also use a thin layer of plumber's grease on the underside of the seal and the bowl will hold water or antifreeze over the winter. Shortly after buying the MH I changed out the model 300 with a 320.

[Farmgal2033]

I had the same issue. After replacing my Dometic 310 , I took the old one apart. On the side of the flush pedal, if you remove the small cap there is a screw that tightens the mechanism for the flush ball. After I tightened the screw, the old toilet works perfectly.

[NMWildcat]

Originally Posted by wayne Dwyer

I have to replace the seals twice a year, a very poor design

And it appears I re0lace mine every 10 years. Hmmmmm
Might try plumbers grease and not letting the seal dry out......

[carlson]

Thanks everyone for your suggestions! I did a little closer inspection of the float ball and seal in my Dometic 310 series toilet as it seemed the flush ball was not returning enough to seal against the flush ball seal and lo and behold, one arm of the flush ball mechanism had come out of the hole it is supposed to be seated in. Once I snapped the arm back in place, the ball returned to it's correct position and tight against the seal, no more water leakage and I have some extra seals now in case the seal ever goes bad.

[NMWildcat]

Congrats on fixing your problem! Amazing how much you can learn from this forum.
Happy RVing!