Valvetrain Assembly Overview

Valvetrain Assembly Overview


Risk of damaging valves and piston heads after working on valvetrain.

• The motor must not be started for about 30 minutes after installing camshafts because the hydraulic equalization elements must seat themselves.

• To ensure valves do not strike pistons when starting, carefully rotate the crankshaft at least 2 turns.

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






1 Shaft Seal

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

2 Bolt

• Loosening sequence => [ Loosen the guide frame bolts and nuts
in the sequence. ] Service and Repair

• Tightening specification and sequence

3 Nut

• Loosening sequence => [ Loosen the guide frame bolts and nuts
in the sequence. ] Service and Repair

• Tightening specification and sequence

4 Bearing Bracket

• With integrated camshaft bearings

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

5 Exhaust Camshaft

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

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

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

6 Intake Camshaft

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

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

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

7 Roller Rocker Lever

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

• Mark the installed position for installation later

• Check roller for easy movement

• Lubricate the running surfaces before installing

8 Hydraulic Adjusting Elements

• With a locking clip

• Mark the installed position for installation later

• Lubricate the running surfaces before installing

9 Valve

• Do not rework, only grinding is permitted

• Mark the installed position for installation later

• checking => [ Valves, Checking ] Testing and Inspection

• Valve dimensions => [ Valve Dimensions ] [1][2]Specifications

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

10 Cylinder Head

11 Valve Stem Seal

• Replacing: cylinder head installed, refer to => [ Valve Stem Seals, Cylinder Head Installed ] Valve Stem Seals, Cylinder Head Installed, cylinder head removed, refer to => [ Valve Stem Seals with Cylinder Head Removed ] Valve Stem Seals With Cylinder Head Removed

12 Valve Spring

13 Valve Spring Plate

14 Valve Retainers

15 Cap

• Replace

• Removing: with the guide frame installed, pierce through one side of the cover with an awl and pry it out.

• Installing: install without sealing compound and thrust piece

• Depth 1 to 2 mm

Guide Frame Tightening Specifications and Sequence





- Tighten guide frame bolts and nut in 2 stages in - 1 to 24 - sequence as follows:

- Insert bolts evenly by hand all the way.

• The guide frame must be in contact with the entire contact surface of the cylinder head.

- Tighten to 10 Nm.