Camshaft: Adjustments

11 31 505 - Adjusting camshaft timing (N51)





Special tools required:
- 00 9 120 00 9 120 Torque Angle Measuring Dial
- 00 9 250 00 9 250 Torque Wrench with Flexible Extension
- 11 0 300 11 0 300 Mandrel
- 11 4 280 11 4 280 Gauge
- 11 4 281
- 11 4 282
- 11 4 283
- 11 4 290 11 4 290 Gauge
- 11 9 340 11 9 340 Device





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





Remove fastener (1) in direction of arrow.

Installation:
Install fastener (1) with bore facing outwards.





Rotate crankshaft at central bolt into TDC position.
Slide in special tool 11 0 300 in direction of arrow and block crankshaft.

Important!
On engines with automatic transmissions, there is shortly before the special tool bore for the TDC position a large bore which can be confused with the special tool bore.

If the flywheel is secured in the correct bore with special tool 11 0 300, the engine can no longer be moved at the central bolt.





With 1st cylinder in firing TDC position, cams of inlet camshaft (1) point upwards at an angle.





Part numbers (2) on twin surface of inlet and exhaust camshafts (1) point upwards.





With 1st cylinder in firing TDC position, cams of exhaust camshaft (3) at 6th cylinder point downwards at an angle.

Note:
If the timing is checked while the engine is installed, the position of the camshaft can only be checked with a mirror.





Important!
Risk of damage!
To open central bolt, mount special tools 11 4 283 11 4 281 and 11 4 282 on camshaft.





Release central bolts (1).
Release central bolts (1) with special tool 11 4 280 only.
Release chain tensioner (2) (have a cleaning cloth ready).

Note:
Illustrations in CAD do not show special tools.





Turn sensor gears (2) in direction of arrow until locating pins (1) on special tool 11 4 290 match up.
Slide on special tool 11 4 290 in direction of arrow.





Secure special tool 11 4 290 with bolts (1).
Screw special tool 11 9 340 into cylinder head.
Pretension timing chain with special tool 00 9 250 to 0.6 Nm.
Secure both central bolts of adjustment units to camshafts with special tool 00 9 120.
Tightening torque: 11 36 1AZ. Mechanical Specifications





Assemble engine.