Removing and Installing/Replacing Left Inlet VANOS Gear

11 36 142 - Removing and installing/replacing left inlet VANOS gear (S65)





Special tools required:







Important!
Central bolts on VANOS gears have left-hand threads.

Do not release the central bolt of the adjustment units without the special tool 11 9 970 11 9 970 Set of Gauges.

Grease contact surfaces of central bolts with copper paste.





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





Release bolts (1) on cylinder bank 2.

Remove timing case cover (2).

Installation Note:
Replace seal.





Important!
Both inlet and exhaust camshafts can be adjusted in the 1st cylinder firing TDC position.

Danger of mixing up both special tool bores.

The procedure for checking timing Testing and Inspection is different from that for adjusting.





Crank engine at central bolt.

Secure crankshaft with special tool 11 5 320 in firing TDC position of cylinder no. 1.





Position of inlet camshafts, cyl. 5-8, in firing TDC position of cylinder no. 1.

Dihedron of inlet camshafts is vertical to cylinder axis, letters/numbers on camshafts point upwards (E2).





Position of exhaust camshafts, cyl. 5-8, in firing TDC position of cylinder no. 1.

Dihedron of camshafts is vertical to cylinder axis, letters/numbers on camshafts point upwards (A2).





Place special tool 11 9 971 11 9 970 Set of Gauges on inlet camshaft.

Designation (E2) on dihedron points upwards.

Place special tool 11 9 972 11 9 970 Set of Gauges on exhaust camshaft.

Designation (A2) on dihedron points upwards.

Secure special tools 11 9 971 11 9 970 Set of Gauges and 11 9 972 11 9 970 Set of Gauges with bolts (1) on cylinder head to 10 Nm.





Align gearwheels on exhaust adjustment unit with special tool 11 5 370.





Important!
Removal/installation is not possible without hexagon socket screw (2).

Hexagon socket screw (1) must not be longer than 10 mm.

Gearwheels of exhaust VANOS gear are pretensioned with a spring.

Insert M5x10 hexagon socket screw on VANOS gear.

Note:
Picture shows cylinders 1-4.





Important!
CCW thread!

Release central bolt (2).

Installation Note:
Replace central bolt (2).





Remove exhaust adjustment unit (1).





Installation Note:
If the hexagon socket screw is released or forgotten by mistake, the gear teeth can be readjusted with special tool 11 5 370.

Screw in knurled screw on special tool 11 5 370 until gearwheel (1) lines up with bore (see arrow) on thread.

Failure to tension the exhaust VANOS gear (1) will result in rattling noises at idle.

Note:
Picture shows (S85).





Installation Note:
Check O-ring (1) on VANOS gear, replace if necessary.





Release chain tensioner (1).

Installation Note:
Replace sealing ring.

Tightening torque: 11 31 1AZ Mechanical Specifications.





Important!
CCW thread!

Release central bolt (1).

Installation Note:
Replace central bolt (1).

Remove inlet adjustment unit (2).





Open plug (1).

Installation Note:
Replace seal.

Tightening torque: 11 12 4AZ Mechanical Specifications.





Secure screw connection against falling out with special tool 11 5 292.

Release screw connection at chain guide with special tool 11 5 291.





Remove inlet adjustment unit.

Lay timing chain (1) on inlet camshaft.

Important!
Do not bar engine at central bolt.

Risk of damage!to engine valves and timing chain.





EIN - Inlet adjustment unit
AUS - Exhaust adjustment unit






Important!
Replace central bolt of adjustment unit.

Central bolt must be fully screwed once.





Important!
Rotate crankshaft at central bolt back until special tool 11 5 320 can be secured in the 10° position.





Installation Note:
Coat contact face of new central bolt (1) with copper paste.





Position VANOS adjustment unit on camshaft.

Hexagon socket screw points upwards.

Insert central bolts (1 and 2) without play.





Remove hexagon socket screw (1) or special tool 11 5 370.

Note:
Picture shows cylinders 1-4.





Secure timing chain tensioning rail.





Install chain tensioner (1).

Installation Note:
Replace sealing ring.

Tightening torque: 11 31 1AZ Mechanical Specifications.





Insert central bolt (1) and screw with special tool 00 9 120.

1. Joining 10 Nm
2. Joining 20 Nm
3. Settling torque 80 Nm
4. Torsion angle 200°
5. Unscrew central bolt.
6. Joining 10 Nm





Insert central bolt (2) and screw with special tool 00 9 120.

1. Joining 10 Nm
2. Joining 20 Nm
3. Settling torque 80 Nm
4. Torsion angle 200°
5. Unscrew central bolt.
6. Joining 10 Nm





Camshafts, cylinders 5-8, remain secured with special tool 11 9 970.

Release special tool 11 5 320 and continue barring engine at central bolt 10° to firing TDC position of cylinder no. 1.

Installation Note:
This minimizes timing chain and gearwheel play.

Secure crankshaft with special tool 11 5 320.





Cylinders 5 to 8:

Always start screwing on the inlet side.

Secure central bolt (1) with special tool 00 9 120.

Important!
Central bolt final tightening.

1. Joining 20 Nm
2. Settling torque 80 Nm
3. Torsion angle 200°





Secure central bolt (1) with special tool 00 9 120.

Important!
Central bolt final tightening.

1. Joining 20 Nm
2. Settling torque 80 Nm
3. Torsion angle 200°





Remove all special tools.

Check timing Testing and Inspection, cylinders (5 to 8).

Assemble engine.