12 31 020 Removing and installing or replacing alternator (N55)

Necessary preliminary work

NOTE: In order to remove the alternator, it is necessary to REMOVE the air conditioning compressor .

In so doing:

Do not draw off A/C system refrigerant.
Do not detach refrigerant lines from A/C compressor.
Do not remove air conditioning compressor; instead, release from bracket only and place to one side.

Release screws (1).

Tightening torque 12 31 1AZ .

Release screw (2).

Tightening torque 12 31 2AZ .

Release screw (3) and remove with holder (4).

Tightening torque 12 31 2AZ .

Fig 1: Identifying Alternator Mounting Screw And Holder

Courtesy of BMW OF NORTH AMERICA, INC.

Unlock connector (1) and remove.

Remove protective cap (2) and release nut underneath.

Tightening torque 12 42 1AZ .

Remove positive battery cable(3).

Fig 2: Identifying Alternator Connector And Protective Cap

Courtesy of BMW OF NORTH AMERICA, INC.

NOTE: For purposes of improved clarity, illustrations and description show A/C compressor removed.

Release screws (1) a few turns until bracket (2) is loose. Do not remove bracket (2).

Tightening torque 12 31 3AZ .

Feed out alternator (3) and remove.

Fig 3: Identifying Alternator, Screws And Bracket

Courtesy of BMW OF NORTH AMERICA, INC.

Assemble engine.