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Certain factors can cause the irregular flow of coolant in the engine and those factors are loose tension belt, broken tension belt and spoilt water pump. For loose tension belt and broken tension belt, this will affect the rotating power of the water pump. In essence, the water pump will not circulate the coolant around the engine efficiently and this will cause overheating. It is the job of the water pump to circulate coolant under force around the engine; therefore any factor that affects that stipulated force will affect the cooling system of the radiator and therefore affect the temperature of the engine. A spoilt water pump also leads to the same effect.

Solution

To prevent overheating, it is wise to check belt tension on a daily bases and to change the belt at any notice breakage on the belt. And on overheating, it is wise to also check the belt tension for correction before checking for leakage and blockage.