The physical process of turbocharger water-cooling is an interesting one, and works in a different way than what might seem obvious. It is true that during normal engine operation water fl ows through the turbocharger mostly due to pressure created by the engine’s water pump. However, an additional phenomenon known as “thermal siphoning” pulls water through the turbo’s center housing if the water lines are properly routed, even after the engine is shut off and the water pump is no longer pumping