Overview - VALVETRAIN

WARNING: This page is about a different variant/trim than selected.

NOTE:

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.

Replace the gaskets and seals.

After performing work on the chain drive the adaptation value in the Engine/Motor Control Module must be adapted. To do so, turn on the ignition and select the following menu items on the Vehicle Diagnostic Tester:

01 - Engine Electronics

Guided Functions

01 - Adaptation after repair work on the chain drive

Fig 1: Exploded View Of Valvetrain

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

Exhaust Valve
- Do not rework, only lapping is permitted
- Valve Dimensions. Refer to VALVE DIMENSIONS .
- Valve Guides, Checking. Refer to VALVE GUIDES, CHECKING .
Cylinder Head
Valve Stem Seal
- Replacing. Refer to VALVE STEM SEALS, REMOVING AND INSTALLING .
Valve Spring
Valve Spring Retainer
Valve Retainers
Hydraulic Lifter
- Do not interchange
- Lubricate the contact surface
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
Exhaust Camshaft
- Removing and installing. Refer to CAMSHAFT, REMOVING AND INSTALLING .
- Check the radial clearance using Plastigauge^® (roller rocker lever removed)
- Radial clearance: 0.024 to 0.066 mm
- Run-out: maximum 0.04 mm
Spring
- No replacement part
Ball
- For sliding bar
- Installing. Refer to SLIDING BAR BALL, INSTALLING .
Cylinder Head Cover
- With integrated camshaft bearings
- Clean the sealing surface, reworking is not permitted.
- Remove old sealant residue.
Bolt
- Replace after removing.
- Loosening. Refer to Fig 2.
- Tightening sequence. Refer to Fig 3.
Intake Camshaft
- Removing and installing. Refer to CAMSHAFT, REMOVING AND INSTALLING .
- Check the radial clearance using Plastigauge^® (roller rocker lever removed)
- Radial clearance: 0.024 to 0.066 mm
- Run-out: maximum 0.04 mm
Alignment Pins
Alignment Pins
Intake Valve
- Do not rework, only lapping is permitted
- Valve Dimensions. Refer to VALVE DIMENSIONS .
- Valve Guides, Checking. Refer to VALVE GUIDES, CHECKING .

Cylinder Head Cover, Loosening

Fig 2: Cylinder Head Cover Bolt Loosening Sequence

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- Loosen the cylinder head cover in the sequence -1 through 6-.

Cylinder Head Cover Tightening Sequence

Fig 3: Cylinder Head Cover Bolts Tightening Sequence

Courtesy of VOLKSWAGEN GROUP OF AMERICA, INC.

-- Replace the bolts after removing them.

Step	Screws	Tightening Specification/Additional Turn
1.	-1 to 6-	Install hand-tight in several stages
2.	-1 to 6-	8 Nm
3.	-1 to 6-	90° additional turn

NOTE:

Pay attention that the cylinder head cover is not tilted.