For the purpose of the removal and installation of the coolant pump and the N52 engine, the below are the procedures; In the engines of the BMW models, the coolant pump requires a removal of the splash shield which is located below the engine. Empty the coolant out of the cooling system, and protect the alternator from corrosive action of the coolant. Finally, the coolant
Thermostat shall be unplugged, the hose clamps be unscrewed and the coolant hose be separated from the back of the pump. Unscrew the electrical connector, after that unbolt the pump and take it off from the side of the engine. If the coolant pump is to be re-used, it has to be refilled with a 50/50 solution of anti-freeze and distilled water the moment it is removed and the holes have to be covered to prevent anything. The process of installation is just the opposite to the process of removal and while reconstructing, care is taken to replace all aluminum fasteners and it is advised not to use steel fasteners which can result in electrochemical corrosion. Replace the thermostat with a new one, replace the refrigerant and evacuate the system and finally look for leaks.