Warning! Do not open the expansion tank cap on a hot engine - you risk scalding. Do not leave containers with coolant - it is poisonous.
1. The coolant level depends on the engine temperature. When the engine is cold, the coolant level should be slightly above the "MIN/MAX" mark on the side of the tank. As the engine warms up, the level rises accordingly.
2 If you need to top up the fluid, wait until the engine has cooled down. Slowly unscrew the expansion tank cap, relieving any possible pressure in the system. Remove the cap.
3. Add a mixture of water and antifreeze to the expansion tank to the "MAX" mark, then tighten the cap tightly.
Prevention
A closed cooling system does not require regular refilling of the fluid. If you have to do this often, there are leaks in the system. Check the radiator, all hoses and their connections for signs of leaks. If a leak is found, fix it as soon as possible.
Use antifreeze all year round. Do not add pure water to the cooling system, as this lowers the boiling point and increases the freezing point.