16100-39565 16100-09650 16100-09620 16100-09740 refers to the engine water pump assembly for Toyota and Lexus brands.

Although the car water pump has a simple structure, it is the power source for the engine cooling system and is crucial to the engine’s health. Understanding its function, working principle, and common faults helps car owners to identify potential problems in a timely manner and perform proper maintenance, thus avoiding major issues and protecting the expensive engine.