ᐅ Toilet with built-in cistern is leaking / constant drip

Good morning everyone,

We have been dealing with a problem for some time now where water runs quietly but continuously in our toilet, even though everything seems to be turned off.
I thought it couldn’t be that difficult, so I went to the hardware store.
The first recommendation there was to replace the seal for the flush valve (also called the tank ball or flapper).

So I invested 2.90 euros and replaced it after some fiddling.
It worked for the first 2-3 flushes, but then the slow drip returned.
Then I ordered and replaced the entire flush valve, but still no improvement.

What else could it be?

One idea I have is that there might be dirt or limescale where the valve seal needs to close.
But how do you get in there and what do you use to clean it? It’s all very tight and built-in, and you can’t really see anything.
I even tried holding my GoPro action camera in there, but it didn’t help much.

I’m afraid that if I call a professional, we might end up having to renovate the entire wall or bathroom afterwards. 😉

I know this from our old house and had to try several seals until it worked. Apparently, there are several options.

Possibly a small dirt particle in the cistern that gets under the new seal and causes water to run continuously again.

hampshire schrieb:

I’ve experienced this in our old house and had to try several seals before finding the right one. Apparently, there are quite a few options.

I’ve already tried two, at least. The new seal from the hardware store and the one that came with the lift.
So I don’t think that’s the issue. But maybe I’ll get some more just in case.
They’re reasonably priced anyway.

seat88 schrieb:

Possibly a small dirt particle inside the toilet cistern, which gets under the new seal and causes water to keep running.

That’s what I suspect as well. Do you have any suggestions on how I could clean that?
The toilet brush doesn’t fit inside. 😉
I had thought about using a hose that fits into drain pipes and connecting it to a pressure washer.
I have one, but it would probably flood half the bathroom.
I’ll try reaching in with a cloth. Maybe I can get to it that way..

Thanks a lot to both of you so far.

Since it’s not a pneumatic box, the lever might simply be too long. Either screw it in further or shorten it slightly. That could be all there is to it.

Thanks to you as well, Mycraft. Ideas are always warmly welcome. I will look into the matter again and report back...