Expansion Tank Keeps Unused Coolant Secure

Anthony Fontanelle
January 9, 2008

The combustion process in the engine generates huge amounts of heat. Hence, an efficient cooling system is needed to avoid overheating and its harmful effects. The cooling system is composed of various components that help in maintaining the engine’s normal operating temperature. The radiator is the main player in the cooling system, but another important component is the expansion tank.

Connected to the radiator through the expansion tank hose, the expansion tank is sometimes called the overflow tank, coolant reservoir, or overflow canister. The expansion tank is a plastic container used as an extra storage for the coolant when it expands. The coolant is a mixture of antifreeze and water that absorbs heat from the engine. Due to the excessive heat created by the engine, the coolant expands. The coolant flows around the cooling system and to the expansion tank as it expands and contracts. This is where the role of the expansion tank comes in. It catches the expanding coolant to prevent it from spilling onto the street. An overflow tank hose is needed for the coolant to flow from the radiator to the expansion tank. When the engine cools, the overflow tank hose sucks back the coolant.

The expansion tank is also used to remove air bubbles from the cooling system. A coolant without air bubbles is better because it can absorb heat much faster than a coolant with air bubbles. The expansion tank keeps the coolant in the radiator full, even if the coolant level in the tank itself continuously rises and falls.

Most cars today come with a cooling system equipped with an expansion tank. For older cars, installing an expansion tank is very easy. Motorists simply need to place the overflow tank near the radiator and get some overflow tube to connect it. Motorists also need to replace the radiator cap to make the newly installed coolant reservoir work efficiently.

Source:  Amazines.com