12 41 020 Removing and Installing/Replacing Starter (N52, N52K, N51, N53, N54)
Aluminum-magnesium materials.
No steel screws/bolts may be used due to the threat of electrochemical corrosion.
A magnesium crankcase requires aluminum screws/bolts exclusively.
Aluminum screws/bolts must be replaced each time they are released .
The end faces of aluminum 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:
- Switch off ignition
- Disconnect battery negative lead (See 61 20 900 DISCONNECTING AND CONNECTING BATTERY NEGATIVE LEAD and/or 61 20 900 DISCONNECTING AND CONNECTING BATTERY NEGATIVE LEAD )
- Remove intake air manifold
Unlock plug (1) and remove.
Unfasten nut.
Tightening torque 12 41 3AZ, see ENGINE ELECTRICAL SYSTEM -- TORQUE SPECIFICATIONS -- TWIN TURBO .
Remove battery positive lead (2).
Release bolt (1).
Installation:
Replace aluminum screws.
Tightening torque 12 41 1AZ, see ENGINE ELECTRICAL SYSTEM -- TORQUE SPECIFICATIONS -- TWIN TURBO .
Release screws (2).
Installation:
Replace aluminum screws.
Tightening torque 12 41 2AZ, see ENGINE ELECTRICAL SYSTEM -- TORQUE SPECIFICATIONS -- TWIN TURBO .
Remove starter motor (3).
Installation:
Check starter pinion and ring gear for damage, replace starter motor if necessary.