Camshaft: Adjustments

11 31 505 Adjusting Timing Of Camshaft(s) (N55)

Special tools required:







IMPORTANT:
For the positioning of the special tool 11 4 281 on the mounting flats of the intake camshaft, it may involve a collision with the cylinder throttle return spring 1.
Special tool 11 4 281 reworked according to the following description.







Necessary preliminary work:
- Remove cylinder head.
- Check timing.







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







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







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







Secure special tool 11 4 285 with bolts (1) to cylinder head.

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

Mount reworked special tool 11 4 281 on the intake camshaft.
Mount special tool 11 4 281 on the exhaust camshaft.







IMPORTANT: Release central bolts (1 and 2) of the Vanos unit only with special tool 11 4 280.

Release central bolts (1 and 2).







Release chain tensioner (1).
Tightening torque 11 31 6AZ.

IMPORTANT:
Have a cleaning cloth ready. A small quantity of engine oil will emerge after the screw connection has been released.
Make sure no engine oil runs onto belt drive.

Installation:
Replace sealing ring.







Turn camshaft sensor wheels (2) in direction of arrow until the retaining pins (1) on the special tool 11 4 290 match up.
Push special tool 11 4 290 in direction of arrow.







Attach special tool 11 4 290 with bolts.

Installation:
Replace both central bolts.
Screw in both central bolts.
Release both central bolts 90°.

11 9 340 Screw special tool into cylinder head.







Pretension timing chain with special tool 11 9 340 and 00 9 250 to 0.6 Nm.







Fasten central bolts of the intake adjuster with special tool 00 9 120.
Tightening torque 11 36 1AZ.







Fasten central bolts of the exhaust camshaft adjuster with special tool 00 9 120.
Tightening torque 11 36 1AZ.







Remove all special tools.
Crank engine on the central bolt and check timing.
Assemble engine.