Operation

System Operation
The coolant pump is belt-driven. Coolant from the radiator outlet (lower right side of radiator) flows to the coolant pump inlet and is pumped through coolant passages in the cylinder block and into the cavities surrounding the cylinder liners. Coolant then flows through holes in the cylinder head gaskets into the cylinder head coolant passages and into the throttle body coolant system. Passages in the intake manifold direct the coolant to the thermostat at the rear of the manifold. When the thermostat is closed (cold engine), the coolant is prevented from returning to the radiator and is recirculated for quick engine warm-up.

Once the engine has warmed sufficiently, the thermostat opens and coolant flows to the inlet tank on the top left side of the radiator. It is cooled as it flows across the horizontal core tubes to the outlet tank on the right side of the radiator, completing the cycle.

Throttle body
The throttle body coolant system uses pipes and hoses to divert coolant to the throttle body. Coolant flows through the throttle body for cold weather starts and helps to warm the incoming air. This helps to provide a smooth idle until the engine reaches operating temperature.