Removal and installation the expansion tank (BMW 7 Series E38)

Models with engines other than M57 and M67

1. Drain the coolant only to a point below the level of the expansion tank.



2. Disconnect the coolant level sensor wiring connector (A), loosen the clamp (B) and disconnect the hose from the expansion tank.

3. Remove the expansion tank cap and completely unscrew the screw to bleed the cooling system.



4. Release the expansion tank mounting plate from the clips.



5. Pull the expansion tank back and remove the ventilation hose.





6. Release the expansion tank from the lower fixing tabs and remove it with an upward movement.

When installed, the holders must fit into the grooves on the fan casing.

7. Installation is carried out in the reverse order. Finally, bleed the cooling system and check it for leaks.

Models with M57 engine

1. Cover the generator to prevent engine oil, fuel or coolant from coming into contact with it.

2. Drain the coolant (see section Replacing the coolant Chapters Vehicle settings and routine maintenance).



3. Disconnect the bypass hose (1). Pull the cap upwards and loosen the clamp (2) securing the air bleed hose. Loosen the clamp (3) and disconnect the hose.

4. Press the lock (4) and remove the expansion tank (5) moving upwards. Disconnect the coolant level sensor wiring connector on the bottom of the expansion tank.

When installing, replace the clamp (2) and move the sensor to the new expansion tank.

Models with M67 engine

1. Drain the coolant (see section Replacing the coolant Chapters Vehicle settings and routine maintenance).



2. Remove the rivets (1), remove the cover (2), squeeze the bracket fixing tabs (3) and remove it with an upward movement.



3. Lift the fan shroud (1) using a screwdriver (2) above the cooling system bleed screw (3). Remove the expansion tank (4) towards the rear.



4. Cut the clamp (1) and disconnect the ventilation hose (2).

When installing, use a new clamp (1).

5. Loosen the clamp (1) securing the water hose (2) and disconnect it from the expansion tank (4). Disconnect the connector (3) of the coolant level sensor.

6. Installation is performed in the reverse order. If necessary, move the coolant level sensor to the new expansion tank.