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Home >> BMW >> 2021 >> M3 Base, Automatic Trans >> Repair and Diagnosis >> External Pages >> Different car >> Section 129 (Engine Electrical System - Repair) >> Alternator With Drive And Mount >> 12 31 ... Replacing Alternator Belt Pulley
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12 31 ... Replacing Alternator Belt Pulley

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2006 BMW M3, 2005 BMW M3, 2004 BMW M3, 2003 BMW M3, and 2002 BMW M3. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:

For Special Tool identification, see SPECIAL TOOLS - M3 .

Special Tools Required: 

Remove and install alternator drive belt.

Depending on alternator type, grip shaft with:

Release nut with special tool 12 7 110.

Installation: 

Tightening torque, refer to 12 31 2AZ/12 31 3AZ in ENGINE ELECTRICAL SYSTEM - TIGHTENING TORQUES .

Fig 1: Releasing Nut With Special Tool 12 7 110
G03118151Courtesy of BMW OF NORTH AMERICA, INC.