Went to do the fluids on the cars the other day and noticed that the Clio's coolant was almost totally gone. A quick look online suggested that the water outlet housing gasket on the 0.9 TCE engines likes to perish and fail, leaking coolant all over the gearbox housing and areas around there. So I had a look with a torch and yep...coolant everywhere. Looked to be the same common issue. New water outlet housing is about £50. Gasket is about £10. I took a chance on just the gasket and set out to repair it.
First I removed the airbox and associated ducting and then the battery tray so I had better access.
Then I was able to remove a fair few pipes/hoses, sensors and vac lines etc. Then after removing the 6 bolts holding it in place - which was not too bad but a couple of tricky ones - I got it out and inspected. The old red gasket was indeed pretty much flush with the housing and not really doing much. The new black gasket I fitted sat proud of the housing and looks as though it would seal well.
Cleaned the corrosion off and got the surface all prepped then refiitted everything. I checked how tight the existing bolts were torqued to by way of trial and error with my torque wrench and worked them out to be about 20Nm, which matches similar housings online. I couldn't find an actual spec for this in either my Haynes, or specifically for the Renault 0.9 TCE engines so went with this. Feels about right.
Lost about 2 litres of coolant maybe, which I caught in various jars out of my neighbours recycling box.
Filled it all back up and used the 3 x bleed screws to bleed it. One to the left of the radiator, one by the water outlet housing and one higher up at the back of the engine bay connected to a hose.
Day 1 and it still lost a bit of coolant which I kind of guessed might happen as it fills out any remaining air gaps.
Day 2 it lost a tiny bit.
Day 3 and I think it's holding strong so will currently assume it is fixed unless it keeps going down again.
No damage appears to have been done to the head gasket and no evidence of mayo in the filler cap as I caught it just before it got really low. Apparently this happens more commonly in the winter where the gasket shrinks back in the cold.