Integrated expansion tank

WARNING: This page is about a different car, the 2002 BMW Z3 and 2001 BMW Z3. However, it is still accessible from the selected car via links, so may be relevant.

Unfasten cap on expansion tank.

Fig 1: Removing Cap On Expansion Tank (Integrated Expansion Tank)

Courtesy of BMW OF NORTH AMERICA, INC.

Remove front underbody protection and unfasten drain plug at bottom of radiator if necessary.

Fig 2: Removing Drain Plug From Bottom Of Radiator

Courtesy of BMW OF NORTH AMERICA, INC.