The primary cooling component in a liquid-cooled engine system, mounted at the front of the vehicle. Hot coolant from the engine block flows into the upper or side tank, travels through a core of thin aluminum or copper-brass tubes, and transfers its heat to the surrounding metal fins. Ram air from driving or a cooling fan pulls heat away from the fins before the cooled fluid returns to the engine.
We need to pressure test the cooling system because there's a pinhole leak somewhere in the radiator core.
Never open a hot radiator cap; the system operates under pressure, which raises the boiling point of the coolant, and releasing it will cause the liquid to instantly flash-boil and spray.
Also heard as
- rad
Related terms
Coolant
A fluid circulated through the engine block and radiator to regulate operating temperature.
Radiator hose
A flexible, reinforced rubber tube that transports coolant between the engine and the radiator.
Intercooler
A heat exchanger used to cool compressed air from a turbocharger or supercharger before it enters the engine.