Leaking push fit connector on toilet

[JukeBoxUK]

I noticed a leak coming from my toilet, only when it is flushed.

After removing panels, I found that the leak is coming from where the water pipe leading from the cistern connects to the back of the toilet (see images below). This seems to be just a push fit which is no longer secure. I can push the pipe back into the back of the toilet but after a bit of use it works its way free again.

I'm just wondering:
(i) whether this is the appropriate type of joint for a toilet
(ii) is there a way to more securely attach the joint
(iii) whether I need to buy a replacement joint of the same type (and, if so, what's the correct name for it)
(iv) whether there is a better joint which I should replace it with

Some photos below.
Photo 1 shows the general set up.
Photo 2 shows the site of the leak (where the black pipe meets the porcelain of the toilet) when it is not connected properly and is leaking
Photo 3 show the connection pushed in tighter so that it does not leak (until it works loose again)

Any advice gratefully received. Thanks!

 

[omega015]

Flush pipe connector is probably worn or that extension (black) piece isn't long enough to keep is securely inserted and its coming out under pressure. Get a replacement flush pipe pan connector and get a decent rubber one not the plastic/pvc ones as they leak/come out easily.
If that pipe is not long enough to ensure that the connector is fully inserted into the pan and that the pipe is fully inserted into the connector then you need to get a new bit of flush pipe too.

Example of one place to get a rubber one: http://www.diy.com/departments/euroflo-flush-pipe-connector/178329_BQ.prd But I prefer to get them online and get the Grohe ones, as they are good quality.

 

[JukeBoxUK]

Thanks for your response. I've taken the connection apart. The rubber connector seems to fine, it's not worn at all. But I think you're right that the black extension piece isn't long enough. Is it possible to replace this piece with a flexible pipe instead? - that would make it a lot easier to fit without having to remove the cistern.

 

[Newboy]

No need to remove the cistern - the flushpipe backnut will unscrew from the bottom of the cistern and release the flushpipe

 

[JukeBoxUK]

I don't think there's anything I can unscrew from the bottom of the cistern. Here's what it looks like now I've taken the black piece off, it seems to be a fixed piece (sorry if I'm being stupid here!).

 

[Bosswhite]

It looks like the Bend is push fit into a socket and the back nut is in the cistern

 

[JukeBoxUK]

All done, I removed the cistern and extended the black connection pipe. It's solid now....hopefully! Thanks guys.

 

[Madrab]

The rubber bung gets greasy and dirty over time too and once it's wet it gets worse. You need to make sure the flush pipe to pan seal, pipe and pan inlet are all squeaky clean, that ensures it stays grippy and watertight.