12 31 020 Removing and installing or replacing the alternator (N63 B40/B44 O 1)

Necessary preliminary tasks: 

• Switch off ignition.
• Disconnect BATTERY NEGATIVE LEAD .
• Remove acoustic cover  . See 11 00 REMOVING AND INSTALLING/REPLACING THE ACOUSTIC COVER (N63 B44 O 0/1) or 11 00 REMOVING AND INSTALLING/REPLACING ACOUSTIC COVER (N63)
• Remove left and right INTAKE FILTER HOUSINGS .
• Remove alternator DRIVE BELT .
• REMOVE CHARGE AIR COOLER EXPANSION TANK .
• PARTIALLY DISENGAGE THE FUEL DELIVERY LINE .

Release clamps (1).

Tightening torque 13 71 8AZ .

Release clamps (2).

Replace clamps (2).

Detach both charge-air ducts (3) and remove.

Check the gaskets on the exhaust turbocharger. replacing if necessary.

Picture shows the left side, the procedure for the right side is identical.

Detach hoses (1) from clean air pipe.

Release screw (2).

Tightening torque 13 71 1AZ .

Detach clean-air pipe (3) in direction of travel from exhaust turbocharger.

Check the gaskets on the clean air pipe. replacing if necessary.

Disengage all the lines and connectors (1) from the alternator holder and put them to the side.

Unlock and pull off connector (1) from alternator.

Release nut at bottom of cover (2).

Tightening torque 12 41 1AZ .

Remove positive battery cable from alternator and place to one side.

Installation note: 

Reinstall cover (2) without fail risk of short circuiting! 

Release screws (1) on turbocharger coolant pump (2).

Place the turbocharger coolant pump to the side. Do not remove the turbocharger coolant pump!

Release screws (1).

Tightening torque 12 31 1AZ .

Feed out and remove the alternator together with the holder in the direction of travel.