I have a minor leak around the bottom corner of the radiator where the plastic channel meets the alloy matrix, just the odd drip after driving. It is on the corner where the bottom hose joins the radiator. I can see a metal claw clip holding the plastic channel onto the alloy core and that is where the leak is. So the question is can this be re-sealed using a repair kit or does it mean the whole radiator has to be changed?

new radiator

At least rads are cheap, I'm surprised they are about £48.

Just had a search around the forums, it seems the fan switch is prone to leaking, is the fan switch directly above the bottom hose connector? If it is then the fluid could be trickling down the side of the rad and making the core to channel seal wet. I haven't dismantled anything yet and the rad is covered in a plastic shroud, so now I'm not sure of my first diagnosis.

fabias do suffer with leaking rads but its more likely to be rad fan switch, Verry common, if it is the fan switch seal has failed and you fit one yourself be carefull not to overtighten as it will warp the rad and you will end up buying a rad as well. its a very easy fix but remember to fefill with some antifreeze, as winter is comming

But where is the fan switch?

Soot1e

The fan switch sits an inch or two above the bottom hose outlet on the rad. Its best to get under the car and remove the splash shield to access it. There's a bunch of cables there, so its no that easy to get at.

Seems that VAG just screw them straight into the rad with no seal. I have had good success on a couple of cars by just unscrewing them and smearing the thread with 'Hylomar Blue' non-setting jointing paste - but you could try a copper washer, silicone seal, PTFE tape on the threads etc etc. You don't need to buy a new switch.

To remove it, first drain the coolant using the tap on the bottom hose (save your coolant in a container if intending to re-use). Remove the electrical connector from the switch and unscrew it using a large socket (32mm or 36mm I think, sorry, can't remember which it was, but about that sort of size).

Bingo! That must be it. The fan shroud looks a bugger to get off. Thanks mate.