Overview - VALVETRAIN

Fig 1: Identifying Valvetrain Overview

Courtesy of AUDI OF AMERICA, LLC

1. 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 .
2. Cylinder Head
   • Valve guides, checking. Refer to VALVE GUIDES, CHECKING .
   • Valve seats, reworking. Refer to VALVE SEATS, REWORKING .
3. Valve Stem Seal
   • Replacing with the cylinder head installed. Refer to VALVE STEM SEALS, REPLACING, CYLINDER HEAD INSTALLED .
   • Replacing with the cylinder head removed. Refer to VALVE STEM SEALS, REPLACING WITH CYLINDER HEAD REMOVED .
4. Valve Spring
5. Valve Spring Retainer
6. Valve Retainers
7. Hydraulic Adjuster
   • Clipped into roller rocker lever -9-
   • Checking. Refer to HYDRAULIC ADJUSTING ELEMENTS, CHECKING .
   • Mark the installed position for installation later
   • Lubricate the running surfaces before installing
8. Clip
   • Not available separately.
   • Make sure it is secure
9. Roller Rocker Lever
   • Mark the installed position for installation later
   • Check roller for easy movement
   • Lubricate the running surfaces before installing
   • To assemble, clip onto the hydraulic adjusting element -8- with securing clip -7-
10. Intake Camshaft
    • Removing and installing. Refer to CAMSHAFTS, REMOVING, USED CAMSHAFTS FOR CYLINDER BANK 1 (RIGHT), REINSTALLING .
    • Axial play, measuring. Refer to CAMSHAFT, MEASURING AXIAL CLEARANCE .
    • Radial play, measuring. Refer to CAMSHAFT, MEASURING RADIAL CLEARANCE .
    • Maximum run out: 0.01 mm
11. Bearing Cap
    • Removing and installing. Refer to CAMSHAFTS, REMOVING, USED CAMSHAFTS FOR CYLINDER BANK 1 (RIGHT), REINSTALLING .
    • Note the installation position
12. Bracket
    • For the tension clamp
    • Tightening specification: 9 Nm. .
13. Bolt
    • Tightening specifications and sequence. Refer to Fig 2, Fig 3
14. Exhaust Camshaft
    • Removing and installing. Refer to CAMSHAFTS, REMOVING, USED CAMSHAFTS FOR CYLINDER BANK 1 (RIGHT), REINSTALLING .
    • Axial play, measuring. Refer to CAMSHAFT, MEASURING AXIAL CLEARANCE .
    • Radial play, measuring. Refer to CAMSHAFT, MEASURING RADIAL CLEARANCE .
    • Maximum run out: 0.01 mm
15. Bearing Block
    • Removing and installing. Refer to CAMSHAFTS, REMOVING, USED CAMSHAFTS FOR CYLINDER BANK 1 (RIGHT), REINSTALLING .
    • Note the installation position
16. Adapter Sleeves
    • Only for the rear thrust bearing with the camshaft axial bearing

Fig 2: Cylinder Bank 1 (Right) Bearing Cap - Loosening And Tightening Sequence

Courtesy of AUDI OF AMERICA, LLC

-- Tighten the bolts in two steps in the sequence shown.

Fig 3: Cylinder Bank 2 (Left) Bearing Cap - Loosening And Tightening Sequence

Courtesy of AUDI OF AMERICA, LLC

-- Tighten the bolts in two steps in the sequence shown.