12 31... Replacing alternator belt pulley

Special tools required: 

• 12 7 110

Remove and install alternator drive belt.

Depending on alternator type, grip shaft with:

• hexagon socket
• multi-tooth socket or
• Torx socket wrench

Release nut with special tool 12 7 110.

Installation: 

For tightening torque refer to 2AZ / 3AZ in 12 31 ALTERNATOR WITH DRIVE AND MOUNTING PARTS .

Fig 1: Identifying Special Tool (12 7 110)

Courtesy of BMW OF NORTH AMERICA, INC.

Procedure with special tool 12 7 121: 

If fitted, remove cover cap from belt pulley.

Depending on alternator type, slacken screw with:

• Torx key
• Hold inner multi-wrench tool (special tool 12 7 122).

Release freewheel with special tool 12 7 121 and remove.

Installation note: 

For tightening torque refer to 8AZ in 12 31 ALTERNATOR WITH DRIVE AND MOUNTING PARTS .

Fig 1: Identifying Special Tool (12 7 121) And (12 7 122)

Courtesy of BMW OF NORTH AMERICA, INC.

Procedure with special tool 12 7 123: 

Depending on alternator type, slacken screw with:

• Torx key
• Hold inner multi-wrench tool (special tool 12 7 122).

Release freewheel with special tool 12 7 123 and a ring spanner and remove.

Installation note: 

For tightening torque refer to 8AZ in 12 31 ALTERNATOR WITH DRIVE AND MOUNTING PARTS .

Fig 2: Identifying Special Tool (12 7 123)

Courtesy of BMW OF NORTH AMERICA, INC.