Leaking toilet flush pipe seal.

[gort]

Morning all!
I have a leak where the cistern pipe enters the back of the toilet pan and an old dodgy gasket / seal is the culprit.
Bought a replacement seal which is supposed to be standard for the 40mm pipe.
I fitted it but it appears to be slightly too large for the hole in the toilet pan as the ribs make it fold up on itself when in, not allowing the pipe to fully fit and it's wanting to push itself out.
Below is a pic of the old and new seals. Material is different also.
Should it just fit (it is a different design)? Lubed it up a bit with washing liquid as recommend.

Ta

 

[Thebug]

Dont push it all the way on the pipe it should have a lip inside what the pipe butts up to but yes they are tight.

We use this one

https://www.screwfix.com/p/flushcon...gclsrc=aw.ds&dclid=COaMl6LvsdkCFcITGwodxLoACA

 

[gort]

Cheers for that.

After a bit of perseverance it turned out that as the new seal is a bit chunkier and slightly different design (thicker lip and ribs) I had to trim down the pipe a couple of mm so it would go in all the way and stay there. No leaks so far.
So not quite a straight swap out old for new as I thought.
Worst thing was thinking I would trim too much off and I'm screwed!

Ta!