Camshaft: Testing and Inspection

11 31 005 Check engine timing of camshaft (N12).

Special tools required:





Important!
Modified procedure for timing adjustment.
The timing is not determined at firing TDC of cylinder no. 1.
All pistons are in the 90° position.
Check locking of adjustment units.
Observe direction of engine rotation (direction of rotation always clockwise when viewed towards timing drive side).





Necessary preliminary tasks:
^ Remove cylinder head cover.
^ Remove front splash guard.





Important!
Danger of mixing up special tool bore.
Balance hole and special tool bore can be mixed up; all pistons must be in the 90° position.
If necessary, determine by means of spark plug bore.

Rotate crankshaft at central bolt.

Position crankshaft with special tool 11 9 590.

Do not remove special tool 11 9 590 during repair work.





Important!
Check locking on VANOS adjustment units.
Attempt to rotate camshaft in direction of rotation at hexagon head.
The adjustment units are locked in the initial position when the camshafts are non-positively connected to the adjustment units.
If no fixed connection to the camshaft can be established, the adjustment unit is faulty and must be replaced.





Both camshafts are in the correct installation position when the designation (IN) for inlet camshaft points upwards.

In the case of the exhaust camshaft, the designation EX must point upwards.





Position of exhaust camshaft (A) points at an angle to the right in an upper outward direction





Position of inlet camshaft (E) points at an angle to the left in an upper outward direction.





11 9 540 Position special tool (exhaust) on dihedron of exhaust camshaft and secure with a screw (1).





11 9 540 Position special tool (inlet) on dihedron of inlet camshaft and secure with a bolts (1 and 2).





If necessary, adjust valve timing.

Assemble engine.