Valvetrain Component Overview

Valvetrain Component Overview





1 Exhaust valve

• Different versions

• 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

2 Sealing plug

• Install with sealant.

3 Cylinder Head

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

4 Hydraulic adjusting element

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

• Do not interchange

• Lubricate contact surface

5 Securing clip

• Check for secure seat

6 Intake camshaft

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

• Checking axial play, refer to => [ Camshafts, Checking Axial Clearance ] Testing and Inspection

• Check radial clearance using Plastigage (roller rocker lever removed)

• Radial clearance at bearing-dia. 24 mm: 0.024 to 0.066 mm

• Radial clearance at bearing-dia. 36 mm: 0.032 to 0.078 mm

• Run-out: max. 0.04 mm

7 Bearing bracket

• With integrated camshaft bearings

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

8 8 Nm plus an additional 90° (1/4 turn)

• Replace

9 Exhaust camshaft

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

• Checking axial play, refer to => [ Camshafts, Checking Axial Clearance ] Testing and Inspection

• Check radial clearance using Plastigage (roller rocker lever removed)

• Radial clearance at bearing-dia. 24 mm: 0.024 to 0.066 mm

• Radial clearance at bearing-dia. 36 mm: 0.032 to 0.078 mm

• Run-out: max. 0.04 mm

10 Roller rocker lever

• Do not interchange

• Check roller for easy movement

• Lubricate contact surface

• To assemble, clip onto hydraulic adjusting element - 4 - using a circlip - 5 -

11 Valve keys

12 Valve spring plate

13 Valve spring

• Installation position: The tight spring coils face toward cylinder head

14 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

15 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