Kühlmittel Warnleuchte leuchtete kurz auf

Zitat von Ilo46

Also bis hierhin warst du mir noch sympathisch haha

Ich beziehe mich nur auf Fakten - hier was zum Nachlesen zu dem Thema. Und mit 2.2L ist der kleine M54 im Cabrio bei mir nun nicht wirklich viel größer - hat aber die entscheidenden zwei Zylinder mehr in der Reihe - vorne da wo bei Dir viiiel Plaste oder Luft im Triebwerksraum ist

Und hier noch was zu meiner Reputation - aus der BMW Pressemitteilung zum N42 mit Valvetronic - da wird beschrieben, das die Wasserpumpe und die Servopumpe im R4 offenbar Leistungsbezogen angesteuert werden - die N46 Wasserpumpe ist ja auch nur doppelt so teuer wie die vom R6 die ja rein mechanisch läuft - eventuell ist da beim N46 eine Thermosteuerung integriert die das Wasser Temperaturabhängig befördert, was dann keinen Strahl bei kaltem Motor erklären könnte - könnte ich weiss es wirklich nicht genau.

Zitat

The engine coolant sections open at the top around the cylinder liners allow the application of a new crossflow cooling concept with only one-quarter of the usual coolant flow resistance. Accordingly, there is no forced circulation of coolant any more in the crankcase, circulation being ensured exclusively by the difference in pressure. As a result, the water pump is only half the size of a conventional unit and its power uptake is down to 60 per cent. The water pump is fitted on the outlet side of the cylinder head on the crankcase, where it is driven together with the steering assistance pump and delivers coolant directly to the cylinder head. At the cylinder head the coolant flows through a long duct initially to the hottest points, the outlet valve supports, and from there to the intake side. The advantage of this crossflow process is excellent cooling efficiency with maximum temperatures approximately 60 ^oC lower than on an engine with coolant flowing longitudinally from one end to the other.

The big benefit for the customer, in turn, is a further reduction in fuel consumption thanks to the reduction in power for running

the water pump and better control of engine knocking due to the more consistent spread of temperature throughout the engine.

The combination of the coolant supply and steering assistance pump on one shaft also offers further advantages over and above a far more compact design: After the engine has been started cold, the coolant warms up more quickly and increases the temperature of the hydraulic fluid in the process, again enabling the hydraulic pump to run on less power. And once the engine has reached its normal operating temperature, the fluid is able to transmit its warmth to the coolant, reducing the maximum temperature of the coolant in this way by approximately 30 ^oC.