Camshaft: Testing and Inspection

11 31 005 - Checking camshaft timing (N14)





Special tools required:
- 11 9 522
- 11 9 551
- 11 9 590





Important!
Modified procedure for timing.

The timing is not determined at firing TDC of cylinder no. 1.

All pistons are in the 90° position.

Check locking of adjustment unit.

Observe direction of rotation (direction of rotation always clockwise when viewed towards timing drive side).





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





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 unit.

Attempt to rotate camshaft in direction of rotation at hexagon head.

The adjustment unit is locked in the initial position when the camshaft is non-positively connected to the adjustment unit.

The adjustment unit is faulty if no fixed connection to the camshaft is established.





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.

Note:
Pictures show N12.





Position of inlet camshaft (1) points at an angle to the right in an upper inward direction.





Position of exhaust camshaft (1) points at an angle to the right in an upper inward direction.





Position special tool 11 9 551 11 9 550 Gauge (exhaust) on twin surface of exhaust camshaft and secure with a screw (1).





Mount special tool 11 9 522 11 9 520 Pressure-Testing Fixture on cylinder head.

Position special tool 11 9 551 11 9 550 Gauge (inlet) on twin surface of inlet camshaft and secure with two screws.





If necessary, adjust valve timing Adjustments.