Valvetrain Assembly Overview

Valvetrain Assembly Overview

• Cylinder head for cylinder bank 2 (left) is shown in illustration.





1 Sealing plug

• Insert with sealant; sealant.

2 Valve stem seal

• Replacing, Cylinder Head Installed, refer to => [ Valve Stem Seals, Cylinder Head Installed, Replacing ] Valve Stem Seals, Cylinder Head Installed, Replacing

• Replacing, Cylinder Head Removed, refer to => [ Valve Stem Seals, Cylinder Head Removed, Replacing ] Valve Stem Seals, Cylinder Head Removed, Replacing

3 Valve spring

• Installed location.

4 Hydraulic adjusting elements

• Clipped into roller rocker lever - 8 -

• Checking, refer to => [ Hydraulic Adjusting Elements, Checking ] Testing and Inspection

• Do not interchange

• Lubricate contact surface

5 Valve spring plate

6 Valve keepers

7 Securing clip

• Not available individually

• Check for secure seat

8 Roller rocker lever

• Do not interchange

• Check roller for easy movement

• Lubricate contact surface

• To assemble, clip onto the hydraulic adjusting element - 7 - with securing clip - 7 -

9 Intake camshaft

• Removing and installing, refer to => [ Camshafts ] Removal and Replacement

• Measuring axial play, refer to => [ Camshaft, Measuring Axial Play ] Camshaft, Measuring Axial Play

• Radial clearance, measuring, refer to => [ Camshaft, Measuring Radial Play ] Camshaft, Measuring Radial Play

• Run-out: max. 0.04 mm

10 Gasket

• Replace

11 Bearing bracket

• With integrated camshaft bearings

• Removing and installing, refer to => [ Camshafts ] Removal and Replacement

12 Bolt

• Replace

• Danger of damaging the camshaft guide frame - for tightening specification and sequence => [ Danger of damaging the camshaft guide frame. ] Removal and Replacement

13 9 Nm

14 Camshaft position sensor, intake camshaft

• Cylinder bank 1 (right) Camshaft Position (CMP) Sensor (G40)

• Cylinder bank 2 (left) Camshaft Position (CMP) Sensor 2 (G163)

15 O-ring

• Replace

16 O-ring

• Replace

17 Camshaft position sensor, exhaust camshaft

• Cylinder bank 1 (right) Camshaft Position (CMP) Sensor 3 (G300)

• Cylinder bank 2 (left) Camshaft Position (CMP) Sensor 4 (G301)

18 9 Nm

19 Exhaust camshaft

• Removing and installing, refer to => [ Camshafts ] Removal and Replacement

• Measuring axial play, refer to => [ Camshaft, Measuring Axial Play ] Camshaft, Measuring Axial Play

• Radial clearance, measuring, refer to => [ Camshaft, Measuring Radial Play ] Camshaft, Measuring Radial Play

• Run-out: max. 0.04 mm

20 Cylinder Head

• Check valve guides, refer to => [ Valve Guides, Checking ] Testing and Inspection

21 Intake valve

• Do not rework, only lapping is permitted

• Mark installed position for re-installation

• Valve dimensions, refer to => [ Valve Dimensions ] [1][2]Specifications

• Check valve guides, refer to => [ Valve Guides, Checking ] Testing and Inspection

22 Exhaust valve

• Do not rework, only lapping is permitted

• Mark installed position for re-installation

• Valve dimensions, refer to => [ Valve Dimensions ] [1][2]Specifications

• Check valve guides, refer to => [ Valve Guides, Checking ] Testing and Inspection

Installed Position of Valve Spring





• The tight spring coils - arrow - face toward cylinder head.