BMW X3 (F25) Service & Repair Manual: Alternator with drive and mounting

• Removing and installing alternator (N52T)
• Removing and installing or replacing alternator (N20, N26)
• Removing and installing or replacing alternator (N55)
• Removing and installing/replacing alternator (N47 D20 O1)

Removing and installing alternator (N52T)

IMPORTANT: Aluminum-magnesium materials.

No steel screws/bolts may be used due to the threat of electrochemical corrosion.

A magnesium crankcase requires aluminum screws/bolts exclusively.

Aluminum screws/bolts must be replaced each time they are released .

Aluminum screws/bolts are permitted with and without color coding (blue).

For reliable identification: Aluminum screws/bolts are not magnetic .

Jointing torque and angle of rotation must be observed without fail (risk of damage) .

Necessary preliminary work:

• Switch off ignition.
• Disconnect BATTERY EARTH LEAD .
• Remove INTAKE SILENCER HOUSING .
• Remove ALTERNATOR DRIVE BELT .

Release connector (1) and remove.

Slacken nut (2).

Installation note:

Disconnect positive battery cable from alternator.

Release screws (3) and remove alternator.

Installation note:

Replace aluminum screws.

Assemble engine.

Removing and installing or replacing alternator (N20, N26)

Necessary preliminary tasks:

• Switch off ignition
• Disconnect BATTERY EARTH LEAD and cover.
• Remove INTAKE SILENCER HOUSING .
• Remove CLEAN AIR PIPE , top.
• Remove TENSIONING DEVICE for drive belt.

Release screws (1).

Unlock connector (1) and remove.

Release nut (2) and remove the positive battery cable.

Disconnect tank ventilation line (3) and place to one side.

Feed out alternator (4) to the left and remove.

Assemble engine.

Removing and installing or replacing alternator (N55)

Necessary preliminary tasks:

• Switch off ignition
• Disconnect BATTERY EARTH LEAD and cover.
• REMOVE LEFT CHARGE AIR DUCT .
• Remove alternator DRIVE BELT .

NOTE: In order to remove the alternator, it is necessary to remove . In so doing:

• Do not draw off air conditioning 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).

Release screw (2).

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

Unlock connector (1) and remove.

Remove protective cap (2) and release nut underneath.

Remove positive battery cable(3).

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).

Feed out alternator (3) and remove.

Assemble engine.

Removing and installing/replacing alternator (N47 D20 O1)

Necessary preliminary work:

• Read out the fault memory of the DDE control unit.
• Switch off ignition.
• Disconnect BATTERY EARTH LEAD .
• Remove INTAKE FILTER HOUSING .
• Remove INTAKE PORT .
• Remove THROTTLE BODY .
• Remove INTAKE PLENUM .
• REMOVE drive belt for alternator.

Release connector (1) and remove.

Slacken nut (2).

Disconnect positive battery cable from alternator.

Slacken nut (1).

Remove cover from idler pulley and undo bolt (1) beneath it.

Remove idler pulley.

Release screws (1).

Feed out alternator upwards and remove.

NOTE: Check stored fault messages.

Delete fault memory.