11 12 000 Removing and installing/sealing cylinder head cover (N52K)
- 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.
- Aluminum screws/bolts are permitted with and without color coding (blue).
- For reliable identification: Aluminum screws/bolts are not magnetic.
- Jointing torque and angle of rotation must be observed without fail (risk of damage).
Necessary preliminary tasks:
- Remove ignition coils. See 12 13 511 REPLACING IGNITION COIL (N52, N52K, N51) .
- Release ignition wiring harness in cylinder head cover area. See 12 51 100 REPLACING WIRING HARNESS SECTION FOR IGNITION COIL (N52K) .
- Remove tension strut.
Unlock and detach vent hose (1). If necessary, pull off metal bracket (2) in direction of arrow. Release screws (3) on electric servomotor. Tightening torque, see 11 37 3AZ in 37 VARIABLE VALVE GEAR .
Release screw on electric servomotor. Tightening torque, see 11 37 3AZ in 37 VARIABLE VALVE GEAR . Remove servomotor (4) in direction of arrow. If necessary, release nuts (5). Tightening torque, see 11 72 1AZ in 72 AIR PUMP, LINES AND CONTROL VALVE . If necessary, remove secondary air valve (6).
Release screws in area (1). Tightening torque, see 11 12 5AZ in 12 CYLINDER HEAD WITH COVER . Installation: Replace aluminum screws.
Release threaded pin (2). Tightening torque, see 11 12 5AZ in 12 CYLINDER HEAD WITH COVER . Installation: Replace aluminum screws.
Installation: Slotted sleeves (2) for guiding ignition coils in cylinder head cover (1) must be replaced. Remove slotted sleeves (2).
Installation: Clean all sealing faces (1 and 2).
Installation: Replace gaskets (1 and 2).
Assemble engine.