After I changed the cabin heater radiator to my ’01 Clio it was obvious that it was not enough. Overpressure in the cooling system was still a problem. After driving, even if the car was not started in 12 hours, there was still so much pressure in the coolant system that if one opened it, a loud psssshhhh was heard. Next thing to do was to change a head gasket. Here are some pics of the process.
And some progress.
Cleaning cylinder head with sandpaper.
Engine bay, top of the cylinders cleaned.
Old gasket was a bit worn..
Fitting a new one..
After this point I kind of forgot to take pics. But repairing succeeded and there was no more overpressure problems.