Hello, my question is perhaps a little more physical. How can an open cooling system in a car still work at higher altitudes? First of all, I would like to ask my question using the example of a Mitsubishi Colt with 1.3 L petrol suction engine and suction tube injection, as well as of course an open cooling system. The cooling system in the Colt is designed so that the thermostat starts to open from 83 °C, then it is completely open from 93 °C. The radiator fan is set so that it starts from 9 5 °C at level one and from 98 °C then runs at level 2 (maximum speed). This has been determined by Mitsubishi, so it is purely about the original thermal management. In normal driving mode, the cooling water temperatures are usually between 86 °C and 88 °C, in case of continuously switched on climate (cooler fan always runs at level 1 at less than 30 km/h). If the air is out and the fan does not run, the engine reaches a level at higher external temperatures. Chrnell his 93 °C and a little later also the 95 °C to let the fan run. So far for explanation. Now water has a boiling temperature of about 100 °C at a height of 0 °C, BUT how does the cooling system now behave at a higher height? What would happen if, for example, the Colt would run on the Großglockner with a height of well over 3 km? At 3 km altitude the boiling point is already at 90 °C, in addition the increased motor load due to the slope, as well as the incoming Loss of power due to the oxygen-poor air. What would happen there with an open cooling system? Is the balancing tank of an estimated 30 cm height sufficient to compensate for the overcooking? Can the water in the pipes bring boiling and air into the system? Would be great if someone could explain the process. It must be somehow ensured that a car with an open cooling system can still work at “larger” heights. Greeting pczwiebel