Valvetrain Assembly Overview

Valvetrain Assembly Overview

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





1 Sealing Plug

• Insert with 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 the contact surface

5 Valve Spring Plate

6 Valve Retainers

7 Securing Clip

• Not available individually

• Check for secure seat

8 Roller Rocker Lever

• Do not interchange

• Check roller for easy movement

• Lubricate the contact surface

• To assemble, clip onto the hydraulic adjusting element - 7 - with securing clip - 4 -

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: maximum 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, refer to => [ Danger of damaging the camshaft guide frame. ] Cylinder Head, Valvetrain - Fastener Tightening Specifications

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: maximum 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 the installed position for installation later

• 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 the installed position for installation later

• 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.