This heat transfer fluid is a mixture of water, ethylene glycol or propylene glycol, and anti-corrosion additives. A water pump pushes it through passages in the engine block to absorb combustion heat, then out to the radiator where airflow dissipates the thermal energy. It raises the boiling point and lowers the freezing point of the water base to prevent block cracking and overheating.
Pressure test the system to see where we're losing coolant, because the radiator is bone dry.
Mixing different colors or chemistry types, like OAT and IAT, can cause the fluid to gel and clog the heater core.
Also heard as
- antifreeze
Related terms
Radiator
A heat exchanger that cools engine coolant by passing it through a network of finned tubes exposed to airflow.
Radiator hose
A flexible, reinforced rubber tube that transports coolant between the engine and the radiator.
Water injection
A system that sprays a fine mist of water into the intake tract to cool the air and fuel charge.