VALVETRAIN Overview

WARNING: This page is about a different car, the 2009 Audi TT and 2008 Audi TT. However, it is still accessible from the selected car via links, so may be relevant.

NOTE:

The cylinder head and guide frame must be replaced together.

Do not start the engine for approximately 30 minutes after installing the camshafts. The hydraulic adjusting elements must seat themselves (otherwise the valves will seat themselves on the pistons).

After working on the valvetrain and lifters, carefully rotate the crankshaft by hand at least 2 full revolutions before starting to be sure that valves do not strike the pistons.

Always replace the gaskets and seals.

Fig 1: Cylinder Head, Camshafts, Overview

Courtesy of AUDI OF AMERICA, LLC

Bolt
- Replace
- 50 Nm plus an additional 180° turn
- Use retainer 3036 for loosening and tightening, refer to Figure
Camshaft Sprocket
Seal
- Removing and installing, refer to EXHAUST CAMSHAFT SEAL
Cylinder Head
- Reworking dimension, refer to Fig 2
Valve Guide
- Checking, refer to VALVE GUIDES, CHECKING
Valve Stem Seal
Valve Spring
Top Valve Spring Retainer
Valve Retainers
Hydraulic Valve Play Balancing Element
- Do not interchange
- Lubricate contact surface
Fitted Key
- Make sure it is secure
Exhaust Camshaft
- Checking axial play, refer to CAMSHAFTS, CHECKING AXIAL CLEARANCE
- Check radial clearance using Plastigage (roller rocker lever removed)
- Radial play with bearing diameter 24 mm: 0.024 to 0.066 mm
- Radial play with bearing diameter 32 mm: 0.030 to 0.051 mm
- Run-out: max. 0.04 mm
Guide Frame
- With integrated camshaft bearings
- Clean sealing surface, reworking is not permitted.
- Remove old sealant residue.
Bolt
- Replace
- Tightening sequence, refer to Fig 3
Camshaft Adjuster
Bolt
- Replace
- 20 Nm plus an additional 45° turn
Intake Camshaft
- Checking axial play, refer to CAMSHAFTS, CHECKING AXIAL CLEARANCE
- Check radial clearance using Plastigage (roller rocker lever removed)
- Radial play with bearing diameter 24 mm: 0.024 to 0.066 mm
- Run-out: max. 0.04 mm
Chain Tensioner
- Removing camshaft timing adjusters, refer to CAMSHAFT ADJUSTER
- Before removing, secure with locking pin T10115
Drive Chain
Bolt
- 10 Nm
Bolt
- 10 Nm
Phase Sensor
Exhaust Valve
- Do not reface, only lapping is permitted
- For the correct valve dimensions, refer to Fig 4
- Valve guides, checking, refer to VALVE GUIDES, CHECKING
Intake Valve
- Do not reface, only lapping is permitted
- For the correct valve dimensions, refer to Fig 4
- Valve guides, checking, refer to VALVE GUIDES, CHECKING
Sealing Cap
- Replace
- Removing: When guide frame is installed: Pierce through one side of the cover with an awl and pry it out
- Installing: Without sealant, press in 1 to 2 mm using the thrust piece 3334

Fig 2: Cylinder Head Refacing Dimension

Courtesy of AUDI OF AMERICA, LLC

-- Resurfacing cylinder head (face grinding) is only permissible to minimum dimension -a-.

Minimum dimension: a = 139.20 mm

Fig 3: Identifying Cylinder Head Bolts Tightening Sequence

Courtesy of AUDI OF AMERICA, LLC

-- Replace bolts

-- Hand-tighten bolts in several stages in sequence -1 through 6-.

-- Tighten the bolts in sequence -1 through 6- to 8 Nm using a torque wrench.

-- Give 90° (¹ /₄ turn) additional turn in sequence -1 through 6- using rigid wrench.

NOTE:

Ensure guide frame is not tilted.

Fig 4: Identifying Valve Dimensions

Courtesy of AUDI OF AMERICA, LLC

NOTE:

Intake and exhaust valves must not be refaced by grinding. Only lapping is permitted.

Dimension		Intake Valve	Exhaust Valve
Diameter a	mm	33.85 ± 0.10	28.0 ± 0.1
Diameter b	mm	5.98 ± 0.01	5.96 ± 0.01
c	mm	104.0 ± 0.2	101.9 ± 0.2
α	∠°	45	45