# Replaced flush valve gasket - still leaking



## Richo (Dec 6, 2007)

I have a Mansfield toilet with a 210 flush valve. The tank has been leaking into the bowl and the obvious culprit would be the seal. There are instructions & videos all over the web on how to fix this and so I bought a new seal/gasket and put it in, but the toilet still leaks. I checked the part that contacts the gasket and it has no visible flaws.

Any other ideas what to look for? Are these seals not all created equal? This was a generic $3 hardware store item. Perhaps poor quality?

Thanks


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## de-nagorg (Feb 23, 2014)

Most times those "one size fits all" things don't.

I would either go to Monsanto for a new part, or build my own using that universal fit item and a tube of R T V automotive gasket silicone.

layer a small bead of R T V on the lower half, lay the fitall in the bead, Then a small bead of R T V on the top half, and lay it on the fitall.

Hand tighten the screws until the R T V sets up and cures, then snug down the screws with a driver, no power tools please.

Then test again.




ED


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## Drachenfire (Jun 6, 2017)

Check the float valve. If may not be rising high enough to shut off the water flow when the tank is full.


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## Richo (Dec 6, 2007)

The problem is with the tank leaking into the bowl though, not leaking outside the tank. This is the seal I replaced (although not the OEM part as shown):










I did check the float and there is no problem with that.


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## ron45 (Feb 25, 2014)

See where it shows the rubber gasket.
Directly above it you see where the assembly screws to the bottom of the water closet, it maybe loose and allowing water to seep into the bowl. If so, you will see water trickling down around the rim of the bowl where water comes out when flushed.


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## Richo (Dec 6, 2007)

This is the exact valve I have though, and the gasket I replaced


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## ZTMAN (Feb 19, 2015)

Looks like the seal you bought is a lot thicker and has a different shape than the one in the video.

Try the OEM and see what happens.

Toilets are getting too complicated these days


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## pwcopy (Aug 27, 2017)

I recently had the same problem with my Mansfield toilet. I bought the $2 aftermarket part at Home Depot, even though half the reviews said it leaked as soon as they put it in. It leaked as soon as I put it in too. I ended up buying a Fluidmaster kit from Ace Hardware for $24. It replaced all the Mansfield parts, was quieter than the OEM gear worked fine from the get go. If you go this route, you'll also have to replace the flush handle, so get one while you're buying the kit. The Mansfield handle won't work with the Fluidmaster flush valve.


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## ct18 (Sep 20, 2012)

Check the height on that gasket. It is easy to push them too far down and the plunger will not seat on them.


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## ron45 (Feb 25, 2014)

Try tightening that big plastic nut under the water closet.


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## Richo (Dec 6, 2007)

ct18 said:


> Check the height on that gasket. It is easy to push them too far down and the plunger will not seat on them.


Turns out that was the problem. Originally I put it on the lowest slot and it leaked. After researching further I found a video explaining that it goes in the top slot so I moved it to the top but it still leaked, just not as bad. I had to move it around and toy with it a bit testing the toilet in between. Seems like a finicky part. The OEM part probably would have been easier, but it looks like it's working fine now.

Thanks for all the replies.


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