Overview - VALVETRAIN
The cylinder head and the cylinder head cover must be replaced together.
Do not start the engine for approximately 30 minutes after installing the camshafts. The hydraulic lifters must seat themselves (otherwise the valves will crash into the pistons).
After working on the valvetrain and engine, carefully rotate by hand at least two full turns to be sure that valves do not strike pistons when starting.
Always replace the gaskets and seals.
After performing work on the chain drive the adaptation value in the engine control module must be adapted. To do so, turn on the ignition and select the following menu items on the Vehicle Diagnostic Tester:
0001 - Adaptation after repair work on chain drive
- Exhaust Valve
- Do not rework, only grinding is permitted
- Valve Dimensions. Refer to VALVE DIMENSIONS .
- Valve Guides, Checking. Refer to VALVE GUIDES, CHECKING .
- Cylinder Head
- Only replace the cylinder head and cylinder head cover together
- Valve Stem Seal
- Replacing. Refer to VALVE STEM SEALS, REMOVING AND INSTALLING .
- Valve Spring
- Hydraulic Lifter
- Do not interchange
- Coat the contact surface with engine oil
- Valve Spring Retainer
- Valve Keepers
- Clip
- For hydraulic lifter
- Roller Rocker Lever
- Removing and Installing. Refer to CAMSHAFT, REMOVING AND INSTALLING .
- Mark the installed position for reinstallation.
- Check the roller bearing for ease of movement
- Lubricate the running surfaces before installing
- Intake side: large narrow roller
- Exhaust side: small wide roller
- Exhaust Camshaft
- Removing and Installing. Refer to CAMSHAFT, REMOVING AND INSTALLING .
- Check the radial clearance using Plastigage® (roller rocker lever removed)
- Axial play: 0.095 to 0.202 mm
- Radial clearance: 0.024 to 0.066 mm
- Maximum run out: 0.04 mm
- Cylinder Head Cover
- With integrated camshaft bearings
- Removing and Installing. Refer to CAMSHAFT, REMOVING AND INSTALLING .
- Only clean the sealing surface, reworking is not permitted.
- Remove old sealant residue.
- Only replace the cylinder head and cylinder head cover together
- Bolt
- Ball Pin
- 9 Nm
- For the engine cover
- Bracket
- For the wiring harness
- Bolt
- 9 Nm
- Plugs
- O-Ring
- Replace after removing.
- O-Ring
- No replacement part: included in the cam adjustment actuator delivery package
- Cam Adjustment Actuator
- Cylinder 1 Intake Cam Actuator B -N577-
- Cylinder 1 Intake Cam Actuator A -N576-
- Cylinder 2 Intake Cam Actuator A -N584-
- Cylinder 2 Intake Cam Actuator B -N585-
- Cylinder 3 Intake Cam Actuator B -N593-
- Cylinder 3 Intake Cam Actuator A -N592-
- Cylinder 4 Intake Cam Actuator A -N600-
- Cylinder 4 Intake Cam Actuator B -N601-
- Removing and Installing. Refer to CAM ADJUSTMENT ACTUATOR, REMOVING AND INSTALLING .
- Bolt
- 4.5 Nm
- Spring
- No replacement part
- Ball
- For sliding bar
- Installing. Refer to SLIDING BAR BALL, INSTALLING .
- Intake Camshaft
- Removing and Installing. Refer to CAMSHAFT, REMOVING AND INSTALLING .
- Check the radial clearance using Plastigage® (roller rocker lever removed)
- Axial play: 0.095 to 0.202 mm
- Radial clearance: 0.024 to 0.066 mm
- Run-out: maximum 0.04 mm
- Alignment Pin
- Quantity: 2
- Intake Valve
- Do not rework, only grinding is permitted
- Valve Dimensions. Refer to VALVE DIMENSIONS .
- Valve Guides, Checking. Refer to VALVE GUIDES, CHECKING .
Loosening the Cylinder Head Cover
-- Loosen the cylinder head cover in the sequence -1 through 6-.
Cylinder Head Cover Tightening Sequence
Replace the bolts that were tightened with an additional turn.
Pay attention that the cylinder head cover is not tilted.
-- Tighten the bolts in the steps shown in the sequence:
| Step | Bolts | Tightening Specification/Additional Turn |
|---|---|---|
| 1. | -1 through 6- | Install all the way in multiple steps by hand |
| 2. | -1 through 6- | 8 Nm |
| 3. | -1 through 6- | 90° additional turn |