Car Parts Finder USAUsed 1999 Toyota 4runner Water Pump

Controls coolant flow to the radiator based on temperature. Often replaced with the water pump as a preventive measure since it is inexpensive and accessible during the job.

Dissipates heat from the coolant. A clogged or leaking radiator causes overheating and should be inspected when diagnosing cooling system problems.

Drives the water pump on many vehicles. Replace if cracked, glazed, or worn since it must be removed for water pump access anyway.

Drives the water pump on many engines. Replace the timing belt, tensioner, and idler simultaneously with a timing belt-driven water pump — the labor overlaps completely.

Monitors engine temperature for the gauge and ECU. A faulty sensor can mask overheating or cause false readings during cooling system diagnosis.

Connect the engine to the radiator. Old hoses become brittle and can fail after a water pump replacement due to the pressure change. Inspect and replace if swollen or cracked.