Parts and service - part 7

The main problem. On the left, the new thermostat. On the right, the old one.

I had been pretty sure that the thermostat in the car was stuck open, until I read about the most common problem with the thermostat, which was being stuck closed :D

Then I realized that there might not be any thermostat inside the housing, for some reason. It didn't occure to me, that the thermostat could break like this :)