To remove and install the coolant pump, on m54 engine first, remove the cooling fan and cowl. Then, turn off the engine and, using a recovery tank, remove the coolant and cover the generator with it not to get damaged by the coolant. To do this, turn the coolant pump pulley slightly counterclockwise to Loosen the coolant pump pulley bolts without removing them Then remove the alternator drive belt and encode the belt direction. Out of the coolant pump pulley bolts and take off the pulley from the pump as well. Removing the coolant pump fasteners; however, tightening two M6 screws into the tapped bores of the pump and keeping them equal until it comes out from the timing chain cover. While installing, make sure that the sealing O-ring and gaskets are put back in, lubricate the O-ring before installation, refill the cooling system and check for any leaks and the last but not the least, fill in the cooling system and bleed it.