Overview - Cylinder Head

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Fig 1: Exploded View Of Cylinder Head

Courtesy of AUDI OF AMERICA, LLC

Check Valve
- For the coolant
Cylinder Head
- Shown for cylinder bank 2 (left)
- Removing and Installing. Refer to CYLINDER HEAD, REMOVING AND INSTALLING .
- Checking for distortion. Refer to Fig 6.
- Reworking Dimensions. Refer to Fig 7.
- Caps, installation and installation position. Refer to Fig 8.
- Change the coolant and engine oil after removing and installing
Bolt
- Replace after removing
- Loosening sequence:
  - Cylinder bank 1 (right). Refer to CYLINDER HEAD BANK 1 (RIGHT), REMOVING, 2.9L ENGINE => Loosen the cylinder head bolts in the sequence -1 to 8-. .
  - Cylinder bank 2 (left). Refer to CYLINDER HEAD BANK 2 (LEFT), REMOVING, 3.0L ENGINE => Remove the bolts -arrows and 9-. .
- Tightening Specifications and Sequence:
  - Cylinder bank 1 (right). Refer to Fig 2.
  - Cylinder bank 2 (left). Refer to Fig 3.
Engine Lifting Eye
Bolt
- 22 Nm
Ball Pin
- 5 Nm +45°
- For the engine cover
Bolt
- 22 Nm
Engine Lifting Eye
Bolt
- Replace after removing
- Loosening sequence:
  - Cylinder bank 1 (right). Refer to CYLINDER HEAD BANK 1 (RIGHT), REMOVING, 2.9L ENGINE - Loosen the cylinder head bolts in the sequence -1 to 8-. .
  - Cylinder bank 2 (left). Refer to CYLINDER HEAD BANK 2 (LEFT), REMOVING, 3.0L ENGINE - Remove the bolts -arrows and 9-. .
- Tightening Specifications and Sequence:
  - Cylinder bank 1 (right). Refer to Fig 2.
  - Cylinder bank 2 (left). Refer to Fig 3.
Cylinder Head Gasket
- Replacing. Refer to CYLINDER HEAD, REMOVING AND INSTALLING .
- Installed position: the part number faces the cylinder head
Bolt
- Replace after removing
- Loosening sequence:
  - Cylinder bank 1 (right). Refer to CYLINDER HEAD BANK 1 (RIGHT), REMOVING, 2.9L ENGINE - Loosen the cylinder head bolts in the sequence -1 to 8-. .
  - Cylinder bank 2 (left). Refer to CYLINDER HEAD BANK 2 (LEFT), REMOVING, 3.0L ENGINE - Remove the bolts -arrows and 9-. .
- Tightening Specifications and Sequence:
  - Cylinder bank 1 (right). Refer to Fig 2.
  - Cylinder bank 2 (left). Refer to Fig 3.

Bank 1 (Right) Cylinder Head - Tightening Specification and Sequence

Fig 2: Bank 1 (Right) Cylinder Head - Tightening Sequence

Courtesy of AUDI OF AMERICA, LLC

Replace bolts that were tightened with an additional turn after removing them.

-- Tighten the bolts in the steps in the sequence shown:

Step	Bolts	Tightening Specification/Additional Turn
1.	-1 to 8-	Install all the way by hand
2.	-1 to 8-	30 Nm
3.	-1 to 8-	50 Nm
4.	-1 to 8-	90° additional turn
5.	-1 to 8-	90° additional turn
6.	-9-	10 Nm
7.	-arrows-	8 Nm
8.	-9-	90° additional turn
9.	-arrows-	90° additional turn

Bank 2 (Left) Cylinder Head - Tightening Specification and Sequence

Fig 3: Bank 2 (Left) Cylinder Head - Tightening Sequence

Courtesy of AUDI OF AMERICA, LLC

Replace bolts that were tightened with an additional turn after removing them.

-- Tighten the bolts in the steps in the sequence shown:

Step	Bolts	Tightening Specification/Additional Turn
1.	-1 to 8-	Install all the way by hand
2.	-1 to 8-	30 Nm
3.	-1 to 8-	50 Nm
4.	-1 to 8-	90° additional turn
5.	-1 to 8-	90° additional turn
6.	-9-	10 Nm
7.	-arrows-	8 Nm
8.	-9-	90° additional turn
9.	-arrows-	90° additional turn

Cylinder Bank 1 (Right) Coolant Ventilation Line, Installing

Fig 4: Cylinder Bank 1 (Right) Coolant Ventilation Line, Installing

Courtesy of AUDI OF AMERICA, LLC

Replace the O-ring after removal.

-- Tighten the bolt -1- to 9 Nm.

Cylinder Bank 2 (Left) Coolant Ventilation Line, Installing

Fig 5: Cylinder Bank 2 (Left) Coolant Ventilation Line, Installing

Courtesy of AUDI OF AMERICA, LLC

Replace the O-ring after removal.

-- Tighten the bolt -arrow- for the coolant ventilation line -3- to 9 Nm.

Cylinder Head, Checking for Distortion

Fig 6: Check Cylinder Head For Distortions

Courtesy of AUDI OF AMERICA, LLC

-- Check the cylinder head at several locations for distortion using a Straight Edge - 500mm: VAS6075 and a feeler gauge.

Maximum permissible distortion: 0.1 mm.

Cylinder Head Reworking Dimension

Fig 7: Cylinder Head Refacing Dimension

Courtesy of AUDI OF AMERICA, LLC

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

Minimum dimension -a- = 138.0 ± 0.1 mm.

Caps, Installation and Installation Position

Fig 8: Cap Installation and Installation Position

Courtesy of AUDI OF AMERICA, LLC

-- Before removing, determine the press-in depth -a-.

-- Coat the cap -1- all around with sealant. Refer to Electronic Parts Information.

-- Position the cap -1- parallel to the cylinder block and using a suitable thrust piece (for example the socket) -2- drive in to the previously determined press-in depth -a-.

Courtesy of AUDI OF AMERICA, LLC