REPLACING ALTERNATOR DRIVE BELT (N51)
Special tools required:
IMPORTANT: Aluminium-magnesium materials.
No steel screws/bolts may be used due to the threat of electrochemical corrosion.
A magnesium crankcase requires aluminium screws/bolts exclusively.
Aluminium screws/bolts must be replaced each time they are released.
The end faces of aluminium screws/bolts are painted blue for the purposes of reliable identification.
Jointing torque and angle of rotation must be observed without fail (risk of damage).
Necessary preliminary tasks:
NOTE: Mark the direction of rotation of the drive belt if it is to be reused.
Layout of drive belt.
Fig. 146: Drive Belt Tensioner, Mounting Screw And Removal Direction
Turn belt tensioner (4) in direction of arrow until bore (2) is flush on housing.
Hold belt tensioner (4) under tension.
Fig. 147: Belt Tensioner And Bore
Secure belt tensioner with special tool 11 3 340.
NOTE: Illustration N42.
Fig. 148: Special Tool (11 3 340) And Belt Tensioner
Remove drive belt (1) towards top.
Fig. 149: Identifying Belt Tensioner
Assemble engine.
Installation:
Check that drive belt for is in correct installation position - risk of damage.
REPLACING ALTERNATOR DRIVE BELT (N52K)
Special tools required:
IMPORTANT: Aluminium-magnesium materials.
No steel screws/bolts may be used due to the threat of electrochemical corrosion.
A magnesium crankcase requires aluminium screws/bolts exclusively.
Aluminium screws/bolts must be replaced each time they are released.
The end faces of aluminium screws/bolts are painted blue for the purposes of reliable identification.
Jointing torque and angle of rotation must be observed without fail (risk of damage).
Necessary preliminary tasks:
NOTE: Mark the direction of rotation of the drive belt if it is to be reused.
Course of E9x drive belt:
Turn belt tensioner (4) in direction of arrow until bore (2) is flush on housing.
Hold belt tensioner (4) under tension.
Load is removed from tensioning pulley.
Fig. 150: Belt Tensioner And Bore
Course of E85 drive belt:
Turn belt tensioner (1) in direction of arrow until bore is flush on housing.
Hold belt tensioner (1) under tension.
Load is removed from tensioning pulley (2).
Fig. 151: Belt Tensioner And Tensioning Pulley
All:
Secure belt tensioner (1) with special tool 11 3 340.
Remove drive belt upwards.
Fig. 152: Special Tool (11 3 340) And Belt Tensioner
Assemble engine.
Installation:
Check that drive belt for is in correct installation position - risk of damage.
REPLACING TENSIONING DEVICE FOR ALTERNATOR DRIVE BELT (N51)
Special tools required:
IMPORTANT: Aluminium-magnesium materials.
No steel screws/bolts may be used due to the threat of electrochemical corrosion.
A magnesium crankcase requires aluminium screws/bolts exclusively.
Aluminium screws/bolts must be replaced each time they are released.
The end faces of aluminium screws/bolts are painted blue for the purposes of reliable identification.
Jointing torque and angle of rotation must be observed without fail (risk of damage).
Necessary preliminary tasks:
Remove special tool 11 3 340.
Release screw (3).
For tightening torque refer to 11 28 1AZ in 28 V-RIBBED BELT WITH TENSIONER.
Installation:
Replace aluminium screws.
Fig. 153: Belt Tensioner And Belt Tensioner Screw
Assemble engine.
REPLACING TENSIONING DEVICE FOR ALTERNATOR DRIVE BELT (N52K)
Special tools required:
IMPORTANT: Aluminium-magnesium materials.
No steel screws/bolts may be used due to the threat of electrochemical corrosion.
A magnesium crankcase requires aluminium screws/bolts exclusively.
Aluminium screws/bolts must be replaced each time they are released.
The end faces of aluminium screws/bolts are painted blue for the purposes of reliable identification.
Jointing torque and angle of rotation must be observed without fail (risk of damage).
Necessary preliminary tasks:
E9x only:
Remove special tool 11 3 340.
Release screw (3) on belt tensioner (4).
For tightening torque refer to 11 28 1AZ in 28 V-RIBBED BELT WITH TENSIONER.
Installation:
Replace aluminium screws.
Remove belt tensioner (4).
Fig. 154: Belt Tensioner And Belt Tensioner Screw
E85 only:
Remove special tool 11 3 340.
Release screw on belt tensioner (1).
For tightening torque refer to 11 28 1AZ in 28 V-RIBBED BELT WITH TENSIONER.
Installation:
Replace aluminium screws.
Remove belt tensioner (1).
Fig. 155: Belt Tensioner And Drive Belt
Assemble engine.