Overview - VALVETRAIN: Notes

Fig 1: Exploded View Of Valvetrain

Courtesy of AUDI OF AMERICA, LLC

1. Bolt
   • Tightening specification -item 2- OVERVIEW - PREGLOW SYSTEM .
2. Camshaft Position Sensor -G40-
   • Overview. Refer to OVERVIEW - PREGLOW SYSTEM .
3. O-ring
   • Always replace after removing
4. Cap
   • Always replace after removing
   • Removing: with the camshaft housing installed, pierce through one side of the cover with an awl and pry it out.
   • Installing: drive in without sealant until it is flush using a suitable thrust piece, such as the Torque Adapter:3390 
5. Camshaft Seal
   • Replacing. Refer to CAMSHAFT SEAL, REMOVING AND INSTALLING .
6. Camshaft Housing
   • With integrated camshaft
   • Removing and installing. Refer to CAMSHAFT HOUSING, REMOVING AND INSTALLING .
   • Do not start the engine for approximately 30 minutes after installing the camshafts.
7. Bolt
   • Loosening sequence. Refer to appropriate service information.
   • Tightening specification and sequence. Refer to TIGHTENING SPECIFICATION AND SEQUENCE FOR THE CAMSHAFT HOUSING .
   • Always replace after removing.
8. Seal
   • Always replace after removing
9. Cover
10. Bolt
    • 8 Nm
11. Bolt
    • 8 Nm
    • Depending on the version, not installed in all vehicles
12. Camshaft Adjustment Valve 1 -N205-
    • Depending on the version, not installed in all vehicles
    • An adaptation must be performed after replacing or removing and installing the Camshaft Adjustment Valve 1 -N205- by using the Vehicle Diagnostic Tester under Guided Functions  , 01 - Adapting the Electric Actuator with Feedback 
    • Removing and installing. Refer to Camshaft Adjustment Valve 1 - N205-, REMOVING AND INSTALLING .
13. Seal
    • Always replace after removing
    • Depending on the version, not installed in all vehicles
14. Bolt
    • Tightening specification and sequence. Refer to CAMSHAFT ADJUSTER HOUSING - TIGHTENING SPECIFICATION AND SEQUENCE .
    • Depending on the version, not installed in all vehicles
15. Housing
    • For camshaft adjuster
16. Alignment Sleeve
    • Depending on the version, not installed in all vehicles
17. Gasket
    • Always replace after removing
    • Depending on the version, not installed in all vehicles
18. Control Valve
    • 50 Nm
    • Depending on the version, not installed in all vehicles
    • An adaptation must be performed after replacing or removing and installing by using the Vehicle Diagnostic Tester under Guided Functions  , 01 - Adapting the Electric Actuator with Feedback 
    • Removing and installing. Refer to Camshaft Adjustment Valve 1 - N205- CONTROL VALVE, REMOVING AND INSTALLING .
19. Camshaft Adjuster
    • Pay attention to the installation of the friction disc (risk of engine damage)
    • Depending on the version, not installed in all vehicles
    • An adaptation must be performed after replacing or removing and installing by using the Vehicle Diagnostic Tester under Guided Functions  , 01 - Adapting the Electric Actuator with Feedback 
    • Removing and installing. Refer to CAMSHAFT ADJUSTER, REMOVING AND INSTALLING .
20. Friction Disc
    • Before installing check that the camshaft adjuster is present
21. Alignment Pins
    • For the camshaft housing
22. Exhaust Valve
    • Do not rework, only lapping is permitted
    • Mark the installed position for installation later
    • Checking. Refer to VALVES, CHECKING .
    • Valve dimensions. Refer to VALVE DIMENSIONS 
    • Valve guides, checking. Refer to VALVE GUIDES, CHECKING .
23. Intake Valve
    • Do not rework, only lapping is permitted
    • Mark the installed position for installation later
    • Checking. Refer to VALVES, CHECKING .
    • Valve dimensions. Refer to VALVE DIMENSIONS 
    • Valve guides, checking. Refer to VALVE GUIDES, CHECKING .
24. Cylinder Head
    • The valve seat may not reworked due to a close tolerances.
    • Cylinder heads with cracks between the valve seats can continue to be used without reducing service life, as long as the cracks have a width of maximum 0.5 mm.
25. Valve Stem Seal
    • Replacing. Refer to VALVE SHAFT SEALS, REMOVING AND INSTALLING .
26. Valve Spring
27. Valve Spring Retainer
28. Valve Retainers
29. Hydraulic Adjuster
    • Mark the installed position for installation later
    • Lubricate the running surfaces before installing
30. Roller Rocker Lever
    • Removing and Installing. Refer to CAMSHAFT HOUSING, REMOVING AND INSTALLING .
    • Mark the installed position for installation later
    • Check roller for easy movement
    • Lubricate the running surfaces before installing
31. Clip
    • For hydraulic adjuster

Loosen the Camshaft Housing Bolts in the Following Sequence: 18 to 1.