Part I

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Part II. Refer to OVERVIEW - VALVETRAIN .

Courtesy of AUDI OF AMERICA, LLC

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
- Only replace together with the cylinder head cover
Valve Stem Seal
- Replacing. Refer to VALVE STEM SEALS, REMOVING AND INSTALLING .
Valve Spring
Valve Spring Retainer
Valve Keepers
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
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.
- Removing. Refer to CAMSHAFT, REMOVING AND INSTALLING .
- Only replace together with the cylinder head
Bolt
- Tightening sequence. Refer to appropriate service information. .
- Always replace after removing.
- Loosening. Refer to appropriate service information. .
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 .

Courtesy of AUDI OF AMERICA, LLC

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

Courtesy of AUDI OF AMERICA, LLC

Replace the bolts that were tightened with an additional turn after removing them.
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 to 6-	Install by hand all the way
2.	-1 to 6-	8 Nm
3.	-1 to 6-	90° additional turn