Valvetrain Overview

Valvetrain Overview

• Cylinder heads with cracks between the valve seats can continue to be used without reducing the service life, as long as the cracks have a Max. width of 0.5 mm.






1 Seal

• Do not lubricate or grease the sealing lip on the seal.

• Before installing, remove any remaining oil from the camshaft journal with a clean cloth.

• To install, tape over the groove on the camshaft taper.

• Removing and installing, refer to => [ Camshaft Seal ] Service and Repair.

2 Bolt

• 10 Nm

3 Nut

• 10 Nm

4 Bearing Frame

• Follow the loosening/tightening sequence. Refer to => [ Camshaft ] Service and Repair.

• Seal using silicone sealant (D 176 501 A1).

5 Exhaust Camshaft

6 Intake Camshaft

7 Roller Rocker Arm

• Mark the installed position.

• Do not interchange.

• Check the roller for easy movement.

• Lubricate the contact surface.

8 Hydraulic Lash Adjuster

• Mark the installed position.

• Lubricate the running surfaces before installing.

9 Valve

• Do not grind, only hand lapping is permitted.

• Mark the installed position for installation later.

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

• Checking the valve guides, refer to => [ Valve Guide, Checking ] Testing and Inspection.

10 Cylinder Head

• See the note in the => [ Cylinder Head Overview ] Cylinder Head Overview.

• Removing and installing, refer to => [ Cylinder Head ] Cylinder Head.

11 Valve Stem Seal

12 Valve Spring

13 Valve Spring Retainer

14 Valve Retainer

15 Sealing Cap

• Always replace.