11 28 020 Replacing tensioning device for alternator drive belt (S65)

IMPORTANT: Mark the direction of rotation of the drive belt if it is to be reused.
Replace the drive belt if it is fouled with coolant or engine oil.

Necessary preliminary tasks:

Release screws (1).

Remove alternator drive belt.

Remove belt pulley (2) from coolant pump.

Fig 1: Identifying Alternator Drive Belt Screws And Belt Pulley

Courtesy of BMW OF NORTH AMERICA, INC.

Release screws (1 and 2).

Remove belt tensioner (3) with tensioning pulley.

Installation:

Observe the installation direction if the belt tensioner is replaced individually.

The lettering TOP must point upwards.

Fig 2: Identifying Belt Tensioner And Screws

Courtesy of BMW OF NORTH AMERICA, INC.

Assemble engine.