Coolant leaks and engine overheating are usually caused by a failing water pump. Automotive water pumps are designed to leak coolant through weep ports as a warning that they are failing. Aside from overheating, a distinctive grinding or whining noise caused by a bad bearing is also a symptom of a bad pump.
Automotive water pumps keep the car's internal combustion engine's temperature at safe ranges by continuously forcing coolant through small passages inside the engine block and cylinder head while the engine is in operation. The coolant absorbs the heat generated by the engine and transfers it to the radiator for dissipation.
A common automotive water pump is a centrifugal pump and is powered by the engine via a belt connected to the crankshaft. This important cooling system component pumps water into the engine by spinning an impeller held by bearings. Depleted coolants and antifreeze become acidic and turn abrasive over time, which causes damage to the bearings and impeller, according to AGCO Automotive Corporation.
According to Auto Hub 360, a broken water pump must be replaced immediately by a professional mechanic to avoid excessive overheating that can leave you stranded and cause severe engine damage, such as a blown head gasket or cracked engine block.