Variable Valve Timing Actuator: Service and Repair

11 36 042 Removing and installing/replacing inlet adjustment unit (N14)

Special tools required:
^ 00 9 120
^ 11 9 550
^ 11 9 551
^ 11 9 552
^ 11 9 590

Important:
Mount special tool 11 9 550 to open central bolts on adjustment units and camshafts.
The timing is not determined at firing TDC of cylinder no. 1.
Modified procedure for timing adjustment.
All pistons are in the 90 ° position.
Check locking of adjustment units.

Necessary preliminary tasks:
^ Remove cylinder head cover.

Slide in special tool 11 9 590 in direction of arrow.
Rotate flywheel (1) at central bolt until firing TDC position at 1st cylinder is reached.

Important:
The TDC bore can be mixed up in automatic transmissions.





Important:
Check locking on VANOS adjustment unit.
Attempt to rotate inlet 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.
If no fixed connection to the camshaft can be established, the adjustment unit is faulty and must be replaced.

Crank engine at central bolt in direction of rotation until designations (IN and EX) can be read from above.





Position special tool 11 9 551 on exhaust camshaft and secure with special tool 11 9 552.
Before fitting special tool, check locking on adjustment unit.
Position special tool 11 9 551 on inlet camshaft and secure with both screws.





Release chain tensioner (1) (have a cleaning cloth ready).

Tightening torque: 11 31 4AZ.





Release screw (1).





Release screws (2).
Remove slide rail (1).





Important:
Release and secure central bolts with special tool 11 9 550 only.

Release central bolt (3).
Remove VANOS adjustment unit (1) from timing chain (2). VANOS adjustment unit of inlet camshaft is marked with the letters IN.





Install slide rail (1).
Insert screws (2).

Tightening torque: 11 31 2AZ.





Screw special tool 11 9 340 into cylinder head.
Pretension timing chain with special tool to 0.4 Nm.





Installation:
Installation position of adjustment unit can be freely selected.
Secure central bolt (1) with special tool 00 9 120.

Tighten VANOS to inlet camshafts
1AZ VANOS to inlet camshafts
M10x52
Jointing torque 20 Nm
Torque angle 180 °





Fit chain tensioner.
Check timing.
Assemble engine.