Water pump: It allows the refrigerant to flow inside of the engine.
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It is inside of the engine but it is surrounded by a serrated belt. The timing belt of the engine moves it. After some time, its internal booster may get damaged and stop pumping liquid. You should replace it every time you change the timing belt.
Had the water pump/ timing belt thermostat coolant temperature sensors two of them done coolant flush out two times and three garage to look at it and it's still overheating can you please help if you can