Camshaft: Adjustments

11 31 505 Adjusting timing of camshaft(s) (N52T)

Special tools required:





Necessary preliminary work:
^ Remove cylinder head cover





Remove fastener (1) in direction of arrow.

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





Rotate crankshaft at central bolt into TDC position.

Slide special tool 11 0 300 in direction of arrow into dowel hole and secure crankshaft.

Important!
On vehicles with automatic transmission, there is a large bore hole for the TDC position shortly before the dowel bore. This bore hole can be confused with the dowel bore.

If the flywheel is secured in the correct dowel hole 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 intake camshaft (1) at 1st cylinder point upwards at an angle.





The part numbers or read-code (2) on the intake and exhaust camshafts (1) point upward.





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

Cam follower (1) is not actuated.

Note:
When the engine is installed, the position of the exhaust camshaft (3) for the timing can only be checked with a mirror.





Secure special tool 11 4 283 with bolts (1) to cylinder head.

Note:
Fit special tool 11 4 282 underneath on side of intake camshaft.

Mount special tool 11 4 281 on intake and exhaust camshafts.





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:
Picture in CAD and does 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).

11 9 340 Screw special tool into cylinder head.

Pretension timing chain with special tool to 00 9 2500.6 Nm.

Secure both central bolts of intake and exhaust camshaft adjusters with special tool 00 9 120 to intake and exhaust camshafts.

Tightening torque 11 36 1AZ.





Assemble engine.