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 aluminium screws/bolts exclusively.
Aluminium screws/bolts must be replaced each time they are released .
Aluminium screws/bolts are permitted with and without color coding (blue).
For reliable identification:
Aluminium 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
- Release Ignition Wiring Harness in cylinder head cover area
- 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.
For tightening torque refer to 11 37 3AZ in 11 37 VARIABLE VALVE GEAR .
Release screw on electric servomotor.
For tightening torque refer to 11 37 3AZ in 11 37 VARIABLE VALVE GEAR .
Remove servomotor (4) in direction of arrow.
If necessary, release nuts (5).
For tightening torque refer to 11 72 1AZ in 11 72 AIR PUMP, LINES AND CONTROL VALVES .
If necessary, remove secondary air valve (6).
Installation location of screws (1 and 2) is specified by the different bushing shapes.
Release screws in area (1).
For tightening torque refer to 11 12 5AZ in 11 12 CYLINDER HEAD WITH COVER (1AZ-12AZ) [N52K] .
Installation:
Replace aluminium screws.
Release threaded pin (2).
For tightening torque refer to 11 12 5AZ in 11 12 CYLINDER HEAD WITH COVER (1AZ-12AZ) [N52K] .
Installation:
Replace aluminium 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.