Flapper leak on Toto Promenade

[alexh]

Hi,

I installed 2 of these a few years ago, CST424EF 1.28 gal.
On one I had to replace the flapper some time ago because of leaking.

It started again, I replaced the flapper but this time it did not help.
For both replacements I used TOTO THU331S flapper which is a universal fit.
The chain has slack.

I looked at the other CST424EF in my house which never had a leak problem and it looks like it still has original flapper, it's not a universal fit type.

Perhaps I should check/clean the sealing surface.

Online it looks like others have had this issue and are using the Korky 2021.

Anyone else aware of this issue?

Thanks

 

[Jadnashua]

Two things to check:
- rub your finger around the sealing surface to ensure it is smooth...if not, the flapper won't seal
- make sure that the extra chain length cannot get caught underneath the flapper...either cut off the excess, or clip it so it won't interfere.

I've found that when the center of the flapper starts to sink and the edges are no longer horizontal, but now are cupped, it's about time to replace the flapper. If you use anything inside of the tank, that will accelerate the degradation of the rubber, and make it softer leading to leaks. In the worst case, the whole flapper will sink into the hole.

This is not usually an issue, but the lever should pull the flapper up fairly straight, not at a big angle. You might slightly bend the arm to get it better centered. In the process, make sure it is not getting caught on anything and moves freely. Make sure to not apply pressure to the area where it is going through the tank, or you might break things.

 

[Sponsor]

 

[JohnSan22]

Contact Toto because I was told that they redesigned the drain (flush) valve called the flush tower about six months ago, eliminating the use of flappers. One of my drake started to leak and after I called them and explained the situation, they sent me a brand new flush valve along with the tank bolts and gaskets free of charge even though I had the drake for five years. Depending on which person you end up with, they may also send you a replacement fill valve.

For your toilet, the part number of the flush tower assembly is THU442.21A-A

 

[WJcandee]

Contact Toto because I was told that they redesigned the drain (flush) valve called the flush tower about six months ago, eliminating the use of flappers. One of my drake started to leak and after I called them and explained the situation, they sent me a brand new flush valve along with the tank bolts and gaskets free of charge even though I had the drake for five years. Depending on which person you end up with, they may also send you a replacement fill valve.

For your toilet, the part number of the flush tower assembly is THU442.21A-A

Maybe, but then you're turning a 2-minute flapper change into a piece of major surgery. Just get the Korky 2021bp flapper, swap it out, and you'll be fine. There have been some issues with the universal flappers; not for everyone, but for some.

Just follow JADNashua's advice above. Jim has it correct.

 

[JohnSan22]

I get that. For my case, replacing the drain valve seemed to solved my issues completely since I would go through a flapper each year due to the fact that I live in a area where the water is very hard and has lots of chlorine in it.

Like wjandee was saying, I would just get one of those universal toto flappers (korky 2023BP NOT 2021BP) from home depot since those would get the job done. Those newer flappers should last a bit longer since the housing is now being reinforced with hard plastic.

The older flappers had a design flaw that would allow the rubber to prematurely wear out and eventually deteriorate too quickly.

 

[Sapote]

This is not usually an issue, but the lever should pull the flapper up fairly straight, not at a big angle. You might slightly bend the arm to get it better centered.

This is a design flaw by Toto to have the chain pulls the flapper up at an angle instead of straight up as you said. Pulling at the angle eventually leading to the flapper outer leg lid in closer to the center pipe, and this caused the misalignment of the flapper, then leak. I'm still using the original 14 years old flapper but I added two spacers to lock the flapper legs at the outer most position. I thought about bending the metal arm to pull the chain up straight, but it seems impossible in this configuration.