The flow through the Mazda radiator core is what makes it possible for the correct temperature of your engine to be maintained. Inside of the radiator core are numerous channels in which the coolant will flow through. These are small channels so the exposure of the coolant to the metal components of the radiator is maximized for the most efficient transfer of heat possible. The reasons for the Mazda radiator core to need replacement are because it has a leak or these small channels are clogged. The leak can be caused by a foreign object piercing through the radiator or the metal of which it is constructed has corroded causing the leak. The clogging of the radiator core on your Mazda car is caused by the coolant system not being properly maintained over time. This allows for sediment to build up in those core channels; in effect reducing the size of the channels and contact surface the coolant has with it. With this surface area being reduced, the amount of heat that can be removed from the coolant will be at a reduced level. The way to maximize the lifespan of your radiator core is to service your cooling system on an annual basis. This is accomplished properly by not only removing the old coolant from the system but flushing it out so as many of the particulates or sediments can also be removed from your Mazda cooling system. The sediments that deposit themselves in the Mazda cooling system originate as dissolved solids from the water that is used to mix with the antifreeze. The only way to have no sediments in the water is to use distilled water for the coolant mixture. This will keep your radiator core free of sediment buildup.