Overview - VALVETRAIN: Notes
WARNING: This page is about a different car, the 2018 Audi S6, 2017 Audi S6, and 2016 Audi S6. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
The cylinder head for cylinder bank 2 (left) is shown in the illustration.
Cylinder heads with cracks between valve seats or between valve seat and spark plug thread can still be used without loss of service life if the cracks are minute (max. 0.3 mm width) or only the first four threads of a spark plug thread are cracked.
- Cylinder Head
- Valve guides, checking. Refer to VALVE GUIDES, CHECKING .
- Valve Stem Seal
- Always replace with the cylinder head installed. Refer to VALVE STEM SEALS, REMOVING AND INSTALLING, CYLINDER HEAD INSTALLED .
- Always replace with the cylinder head removed. Refer to VALVE SHAFT SEALS, REMOVING AND INSTALLING, CYLINDER REMOVED .
- Valve Spring
- Allocation.
- Valve Spring Retainer
- Valve Retainers
- Hydraulic Adjusting Element
- Clipped into roller rocker lever -8-
- Mark the installation position with paint for reinstallation
- Lubricate the running surfaces before installing
- Clip
- Not available individually
- Make sure it is secure
- Roller Rocker Lever
- Mark the installation position with paint for reinstallation
- Check the roller bearing for ease of movement
- Lubricate the running surfaces before installing
- Allocation to the cylinders.
- Clip to the hydraulic lifter -7- with the clip -6-.
- Exhaust Camshaft
- Removing and installing. Refer to CAMSHAFT, REMOVING AND INSTALLING .
- Axial play, measuring. Refer to CAMSHAFT, MEASURING AXIAL CLEARANCE .
- Radial play, measuring. Refer to CAMSHAFT, MEASURING RADIAL CLEARANCE .
- Maximum run out: 0.04 mm
- Camshaft Housing
- With integrated camshaft bearings
- Bolt
- Tightening sequence.
- Always replace
- Use old bolts to measure radial play.
- O-Ring
- No replacement part, included in the cam adjustment actuator package
- Bolt
- 5 Nm
- Intake/Exhaust Camshaft Actuator -F452- through -F479-
- Removing and installing. Refer to CAM ACTUATOR, REMOVING AND INSTALLING .
- Bring into the installed position. Refer to appropriate service information.
- O-Ring
- Always replace
- Sealing Plugs
- Turn to the left to remove with a screwdriver
- O-Ring
- Always replace
- Camshaft Position Sensor 4 -G301-
- Cylinder bank 1 (right) Camshaft Position Sensor 2 -G163-
- Removing and installing. Refer to Camshaft Position Sensor -G40-, REMOVING AND INSTALLING .
- Bolt
- Tightening specification -Item 13- OVERVIEW - IGNITION SYSTEM .
- Bolt
- 5 Nm
- Exhaust Camshaft Adjustment Valve 2 -N319-
- Cylinder bank 1 (right) Exhaust Camshaft Control Valve 1 -N318-
- Removing and installing. Refer to CAMSHAFT ADJUSTER VALVES, REMOVING AND INSTALLING .
- O-Ring
- Always replace
- Bolt
- 5 Nm
- Camshaft Adjustment Valve 2 -N208-
- Cylinder bank 1 (right) Camshaft Adjustment Valve 1 -N205-
- Removing and installing. Refer to CAMSHAFT ADJUSTER VALVES, REMOVING AND INSTALLING .
- O-Ring
- Always replace
- Bolt
- Tightening specification -Item 5- OVERVIEW - IGNITION SYSTEM .
- Camshaft Position Sensor 3 -G300-
- Cylinder bank 1 (right) Camshaft Position Sensor -G40-
- Removing and installing. Refer to CAMSHAFT POSITION SENSORS -G163 - / - G301-, REMOVING AND INSTALLING .
- O-Ring
- Always replace
- Flat Ring
- Always replace
- For Camshaft adjuster
- Intake Camshaft
- Removing and installing. Refer to CAMSHAFT, REMOVING AND INSTALLING .
- Axial play, measuring. Refer to CAMSHAFT, MEASURING AXIAL CLEARANCE .
- Radial play, measuring. Refer to CAMSHAFT, MEASURING RADIAL CLEARANCE .
- Maximum run out: 0.04 mm
- Exhaust Valve
- Different versions. For the correct allocation. Refer to the parts information.
- Do not rework, only lapping is permitted
- Mark the installed position for installation later
- Valve dimensions. Refer to VALVE DIMENSIONS
- Valve guides, checking. Refer to VALVE GUIDES, CHECKING .
- Intake Valve
- Do not rework, only lapping is permitted
- Mark the installed position for installation later
- Valve dimensions. Refer to VALVE DIMENSIONS
- Valve guides, checking. Refer to VALVE GUIDES, CHECKING .
CAUTION:
The engine could be damaged.
- Bring all of the pins for all of the cam adjustment actuators into the installed position.
-- Press down the cam adjustment actuator pins -arrow- by hand.
- The pins for all of the adjusting elements must not be in the outward position.
CAUTION:
The engine could be damaged.
- Pay attention to the allocation of the roller rocker lever to the cylinders.
- Roller rocker lever with wide rollers -arrow 1- belong to the cylinders without cylinder cut-off.
- Roller rocker lever with narrow rollers -arrow 2- belong to the cylinders with cylinder cut-off.
- Short Version for Intake Valve
- Long Version for Exhaust Valve
- The tight spring coils -arrows- face toward the cylinder head.