Not sure if this is the same on the Octavia bit i have a push fit pipe going to where the thermo stat is located. (As you look at the engine it comes from the right along the front of the engine and into the right hand side of the housing, not sure if its the block otsself like the pic or actually the plastic housing..

Anyway.. Is there anything that can be done to replace this? Mine leaks from there and i would rather swap it than replce any 'O' rings etc..

Sent from my iPhone using Tapatalk

New o ring should sort it. Difficult to see but it looks like the o ring might even be hanging out there.

Thats just a generic pic from google. Mine doesnt look like that but is very simular. Think i'll pull it out and have a look when my new thermostat arrives. I'm also putting the correct coolant in[emoji6]

Sent from my iPhone using Tapatalk

I have one for sale with an o ring on the 'bay

 

pm me if you want more info

The pipe pushes into the block casing and like techie mentions, there is an O ring. Problem can be that you get rust scale on the block casing. A new O ring is a good idea, when I replaced mine I smeared a bit of gasket sealant around it too and worked just fine.