Toilet tank leak: flapper not centered

The toilet tank may be 3 or 4 years old. The flapper is Fluidmaster Model 540. Everything is clean and there's no visible tear and wear. But water slowly leaks *unless I push the flapper in the arrow direction* after it shuts (see picture). It can wiggle just by that much (1 or 2 mm) and that's all it needs to stop the leak. I can't think of a way to rotate the flapper by that little. How do I fix it? Thanks.

Try a Korky

How tight is the chain, it looks tight in the picture. the flapper should self center on the opening when closing. To me it looks like the chain is to tight and keeping it off center.

CT-18 said:

How tight is the chain, it looks tight in the picture. the flapper should self center on the opening when closing. To me it looks like the chain is to tight and keeping it off center.

Click to expand...

You just might be right. Kind of hard to see. Good call

Thanks all. I solved the problem. It's not the chain. The flapper really is off-centered a little bit when it goes down by itself. What I did: I wrapped thin copper wire on the "axle" the flapper rotates around, I mean the black plastic stick at the base of the overflow tube. I did it on the outside of the flapper "fork", the one you can't see in the picture. So the copper wire pushes the whole flapper in the direction of the arrow I drew. Sorry for my bad terminology.