Variable Valve Timing Actuator: Service and Repair

11 36 046 - Removing and installing/replacing inlet and exhaust adjustment units (N54)





Special tools required:





Important!
To open central bolts, release at inlet and exhaust adjustment units with special tool 11 4 280 only.





Necessary preliminary tasks:
- Remove cylinder head cover Service and Repair





Remove fastener (1) in direction of arrow.





Slide in special tool 11 0 300 in direction of arrow.

Rotate flywheel (1) at central bolt until firing TDC position at cylinder no. 1 is reached.

Important!
The TDC bore can be mixed up in automatic transmissions.





With cylinder no. 1 in firing TDC position, inlet camshaft (1) at cylinder no. 6 points downwards at an angle to the left.

With cylinder no. 1 in firing TDC position, exhaust camshaft (2) at cylinder no. 6 points downwards at an angle to the right.

Installation Note:
If the timing is checked while the engine is installed, this is only possible with a mirror.





Fit special tool 11 4 283 with screws (1).

Fit special tool 11 4 281 on special tool 11 4 283.





Release central bolt of exhaust adjustment unit (1).

Release central bolt of inlet adjustment unit (2).

Tightening torque 11 36 1AZ Mechanical Specifications.

Release chain tensioner Service and Repair.





Detach exhaust adjustment unit (1) from exhaust camshaft.

Detach inlet adjustment unit (2) from inlet camshaft.

Installation Note:
To facilitate removal and installation of the inlet and exhaust adjustment units, turn the sensor gears at the opening downwards.





Important!
- Risk of mixing up the inlet and exhaust adjustment units.
- Mixing up the inlet and exhaust adjustment units will cause damage to the engine.





The inlet and exhaust adjustment units are different.

VANOS is marked with AUS and EX for the exhaust camshaft.

VANOS is marked with EIN and IN for the inlet camshaft.

Sensor gears can be fitted alternatively.





Position inlet and exhaust adjustment units on camshafts.

Installation position of inlet and exhaust adjustment units can be freely selected.

Installation Note:
Replace screws (1 and 2).

Insert screws (1 and 2).

Adjust valve timing Adjustments.

Fit chain tensioner Service and Repair.





Important!
Incorrect installation possible.

Make sure that timing chain is guided in tensioning rail (1).

Note:
Schematic representation on removed chain drive.





Remove all special tools.

Assemble engine.