FixVault

Engine Cooling: Notes

The engine cooling system undertakes the classic task of carrying heat away from the engine and maintaining a defined operating temperature as constant as possible. As on the N54 engine, the two turbochargers are also cooled.

The N63 engine features a conventional coolant pump that is driven by the belt drive. This pump cannot be used to continue cooling the turbochargers after the engine has been shut down.

Fig 1: Engine Cooling System Diagram
G06925851Courtesy of BMW OF NORTH AMERICA, INC.
COMPONENTS DESCRIPTION CHART

Index Explanation
1 Radiator
2 Radiator for transmission cooling
3 Coolant-temperature sensor at radiator outlet
4 Electric fan
5 Characteristic map thermostat
6 Electric auxiliary coolant pump for turbocharger cooling
7 Coolant pump
8 Exhaust turbocharger
9 Heating heat exchanger
10 Duo-valve
11 Electric auxiliary coolant pump for vehicle heating
12 Vent line
13 Coolant-temperature sensor at engine outlet
14 Expansion tank
15 Vent line
16 Transmission fluid-to-coolant heat exchanger
17 Auxiliary coolant radiator