12 31 020 Removing and installing or replacing alternator (N12, N14)

Necessary preliminary tasks: 

• Switch off ignition
• Disconnect Battery Negative Lead 
• Move Front Panel Into Assembly Position 

N14 only: 

Release bolt.

Remove bracket (1) and place to one side.

Fig 1: Alternator Bracket And Mounting Bolt

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Bring belt tensioner (1) with wrench (2) into assembly position and hold.

Secure assembly position of belt tensioner (1) by sliding locating pin (3) in direction of arrow.

Remove drive belt (4) from alternator.

Fig 2: Alternator Belt Tensioner, Pin, Drive Belt, Wrench And Removal Directions

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Unlock connector and remove.

Release nut (1) and remove battery positive lead.

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

Release screws (2) and remove belt tensioner (3).

For tightening torque refer to 11 28 1AZ  in 11 28 V-RIBBED BELT WITH TENSION AND DEFLECTION ELEMENT .

Fig 3: Screws, Nut And Remove Belt Tensioner

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Release screw with joint extension (1).

For tightening torque refer to 12 31 1AZ  in 12 31 ALTERNATOR WITH DRIVE AND MOUNTING PARTS .

Remove alternator.

Fig 4: Identifying Joint Extension

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