Your car’s radiator keeps your engine from overheating or freezing. That’s its main job, and it’s an important one (some also keep the transmission fluid at a good temp). Technically, a car can run without a radiator, but the engine would overheat super fast. Learn more about this critical piece of equipment and what to look for when it’s time to replace it.
How Does a Radiator Work?Your engine produces a lot of heat. Fortunately, coolant keeps it from overheating. As it flows through and around the engine, the coolant absorbs the heat and carries it to the radiator.
When it reaches the radiator, the coolant flows into tubes. The car’s movement forces air through the rows that run between the tubes, cooling down the coolant as it goes. This dissipates the heat through the vehicle’s grille, and then the coolant is run back into the engine to continue cooling it. As long as the radiator is able to dispel heat quickly enough to keep the coolant efficient, the engine is able to run without overheating.
If the radiator isn’t running efficiently, or isn’t adequate for the horsepower being produced, the engine will overheat.
Parts of an Engine Cooling SystemIn theory, a radiator is a fairly simple heat exchanger. But to function correctly, a radiator needs to be able to pump coolant, store coolant, and exchange heat efficiently. These processes require a few key parts that we'll explain in more detail below.
Radiator CoreThe biggest part of a radiator, and the part people think of first, is the core. The core consists of metal tubes surrounded by small fins where the coolant goes to shed heat. The heat is transferred to the fins, which exist between the tube rows.
Cooling fins are usually made out of thin aluminum and aligned to look like rows of small “v”s between the tubes. Fins can become damaged and clogged from insects and road debris, so it’s good to clean them periodically to keep them functional.
Cores come in different sizes and with different numbers of rows. There are a lot of differences in types of cores, which you can read about here.
Radiators have a pretty long lifespan, and should be able to go for 8-10 years without needing to be replaced.Inlet and Outlet HosesThe inlet hose takes coolant from the engine and pulls it into the radiator. The outlet hose takes the coolant back to the engine. Despite being the simplest part of the radiator, the hoses are also a radiator’s most vulnerable points. Because radiator hoses tend to endure wear and tear internally, you might not realize they’re degrading until they’re actually leaking.
Radiator hoses typically last about 4 years, but they might need to be replaced sooner depending on use.Heater HosesBesides getting rid of engine heat, radiators also reroute heat into the cabin for passengers. The heater hoses connect to the heater core under your dash.
Like radiator hoses, you should replace the heater hoses every four years.
