Flushing the cooling system

Over time the coolant inside the engine cooling system begins to lose its protective properties and may accumulate corrosion particles, scale, and other contaminants. These deposits can build up inside the radiator, engine block, and cooling passages, reducing coolant circulation and lowering the efficiency of heat transfer from the engine. When this happens the engine may run hotter and cooling system components can experience additional stress. A cooling system flush removes old coolant along with accumulated contaminants and restores proper circulation by refilling the system with fresh coolant that meets the correct specifications. This process improves cooling performance and helps extend the life of components such as the radiator, water pump, and other cooling system parts. In some cases the need for a cooling system flush may also be related to a failing oil cooler, also known as an engine oil heat exchanger, where engine oil is cooled by engine coolant. Over time internal seals inside the heat exchanger may wear out, allowing engine oil to mix with the coolant. When this happens, after repairing the faulty component, a thorough flushing of the cooling system is required to remove oil contamination and restore proper cooling system operation.