Coolant: Description and Operation

ENGINE COOLANT

The cooling system contains a special liquid called coolant, or "antifreeze," which circulates through the engine and the radiator. The coolant picks up heat from the engine and transports it to the radiator; where it is dissipated to outside air. Some of the hot coolant can also be circulated through the heater core, where it can warm the air being blown into the passenger compartment.

The antifreeze concentration should be 50%, throughout the year. In addition, the coolant should be drained and refilled according to the recommendations in Specifications.

The cooling system does not need any additives besides a reputable brand of ethylene glycol antifreeze with corrosion inhibitors that are nitrite- and amino-acid free and compatible with aluminum radiators. Antifreeze other than the type specified by BMW for aluminum radiators may cause corrosion of the cooling system, which can lead to engine overheating and damage.