Pump rear end leak

[ChrisR]

This is a MicroGenus 27MFFI, but could be very similar on many other boilers.
Pump is a normal Wilo, with a 3cm thick chamber for the impeller and a rounded plastic rear part with AAV on top.
The rear connection, which goes to t he brass manifold, is sealed with a clip and O ring.
This one is leaking rapidly. Anyone got experience of this? I can change just the O ring, but to get the plastic part you have to buy the whole pump. It may be that the plastic part is distorted.
???
Not easy to access so I'm tempted to change the lot because I don't want to go in there twice.

 

[LUNAT]

HI

picture would be helpfull

 

[nickso]

ive changed the o-ring a few times. not a nice job and you never get the feeling its sealed righ as its a rattling good fit.

never seen the plastic distorted though.

 

[ChrisR]

O ring and rusty clip:

Pump and spigot

 

[ChrisR]

.