Pneumatic flush concealed WC

[Daljit]

Hi

I have an issue with a concealed WC, the air tube from the push button to diaphragm(?) pops off on the latter side. If you hold it in place, flush works fine.

Normally I’d think some sort of jubilee clip could work but diameter of tube too small. It’s also difficult to get a close look at the connection.

Any suggestions?

 

[Tricky-Dicky]

How about these clips, many other similar listings as well.
A 'garage' may have some, as I have seen them used on petrol fuel pipes.

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