Valvetrain Overview

Valvetrain Overview






1 Valve

• Do not rework, only hand lapping is permitted.

• Mark the installed position for reinstallation later.

• Checking, refer to => [ Valve, Checking ] Testing and Inspection.

• For the correct valve dimensions, refer to => [ Valve Dimensions ] [1][2]Specifications.

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

2 Cylinder Head

3 Valve Stem Seal

• Replacing, refer to one of the following:

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, Cylinder Head Removed ] Valve Stem Seals, Cylinder Head Removed.

4 Valve Spring

5 Spring Plate

6 Valve Retainers

7 Sealing Cap

• Always replace.

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

• Installing: Install without using sealing compound and with a thrust piece.

• Depth: 1 to 2 mm.

8 Seal

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

9 Exhaust Camshaft

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

• Checking axial play, refer to => [ Camshaft Axial Clearance, Checking ] Camshaft Axial Clearance, Checking.

• Checking radial clearance, refer to => [ Camshaft Radial Clearance, Checking ] Camshaft Radial Clearance, Checking.

10 Bolt

• Tightening sequence and specification, refer to => [ Guide Frame Bolt Tightening Sequence and Specification ].

11 Guide Frame

• With integrated camshaft bearings.

• Tightening sequence and specification, refer to => [ Guide Frame Bolt Tightening Sequence and Specification ].

12 Intake Camshaft

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

• Checking axial play, refer to => [ Camshaft Axial Clearance, Checking ] Camshaft Axial Clearance, Checking.

• Checking radial clearance, refer to => [ Camshaft Radial Clearance, Checking ] Camshaft Radial Clearance, Checking.

13 Roller Rocker Arm

• Mark the installed position for reinstallation later.

• Check the roller for easy movement.

• Lubricate the running surfaces before installing.

14 Clip

• For the hydraulic lash adjuster.

15 Hydraulic Lash Adjuster

• Mark the installed position for reinstallation later.

• Lubricate the running surfaces before installing.

Guide Frame Bolt Tightening Sequence and Specification





- Tighten the bolts in 2 steps in the sequence shown: