Engine Operation 20 UENR0623-02 Coolant Flow Illustration 17 g02847496 Typical example (1) Radiator (2) Water temperature regulator and housing (3) Exhaust gas cooler (NRS) (4) Cylinder head (5) Cylinder block (6) Water pump (7) Engine oil cooler The coolant flows from the bottom of the radiator (1) to the engine oil cooler (7). The engine oil cooler (7) is installed on the right-hand side of the engine. The coolant flows from the engine oil cooler (7) to the water pump (6). The coolant flows forward through the cylinder head (4). Some coolant is diverted into the exhaust gas cooler (NRS) (3) by a coolant pipe in the right-hand side of the cylinder block (5).
The coolant then flows from the exhaust gas cooler (NRS) (3) back to the housing of the water temperature regulator (2). The water pump (6) contains a rotary seal that uses the engine coolant as a lubricating medium. This will ensure that an adequate sealing film is created. The sealing film is maintained in order to reduce heat generation. Heat that is generated by the rotating sealing faces under normal operating conditions causes a small flow of coolant to be emitted into a chamber. The water pump pumps the coolant through a passage to the main coolant gallery in the cylinder block (5).
Coolant flows around the outside of the cylinders then flows from the cylinder block (5) into the cylinder head (4).