Valvetrain, assembly overview Audi A8 D3 рестайлинг

Valvetrain, assembly overview

Note. 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. After installing the camshafts, the engine may not be started for approx. 30 minutes. The hydraulic equalization elements must seat themselves (otherwise the valves will crash into the pistons). After working on the valvetrain, carefully rotate engine by hand at least 2 full revolutions to ensure that valves do not strike the pistons when starting. Always replace seals, sealing rings and O-rings.

Scheme 203

1 - Double bearing cap

1. Before installing, coat contact surfaces of front and rear bearing caps lightly with sealant --> «Coat bearing cap with sealant»(/audi/a8/d3-2005-2007/remont/cooling-fan/#42l-v8-5v-engine-mechanical-engine-codes-bfm)
2. Sealant

2 - 5 Nm plus an additional 90° ( 1 / 4 turn)

1. Replace

3 - Hydraulic plunger

1. Pressed into roller rocker lever

4 - Exhaust camshaft

1. Checking axial play --> «Camshafts, checking axial clearance»(/audi/a8/d3-2005-2007/remont/cooling-fan/#42l-v8-5v-engine-mechanical-engine-codes-bfm__camshafts-checking-axial-clearance)
2. Removing and installing --> «Camshafts and camshaft adjusters (right cylinder head), removing and installing»(/audi/a8/d3-2005-2007/remont/cooling-fan/#42l-v8-5v-engine-mechanical-engine-codes-bfm__camshafts-and-camshaft-adjusters-right-cylinder)
3. Check radial play using Plastigage (cam follower removed), wear limit 0.1 mm, run-out max. 0.01 mm

5 - Bearing cap for intake camshaft

1. Note installation position and allocation --> see scheme 330
2. Observe alignment bushings if present

6 - Bearing cap for exhaust camshaft

1. Note installation position and allocation --> see scheme 330
2. Observe alignment bushings if present

7 - 5 Nm plus an additional 90° ( 1 / 4 turn)

1. Replace

8 - Double bearing cap

9 - Cap

1. Replace
2. To remove, push through using screwdriver and pry out
3. To install, drive in using retractors 3202 or suitable lever

10 - Bearing cap

1. Before installing, coat contact surfaces of front and rear bearing caps lightly with sealant --> «Coat bearing cap with sealant»(/audi/a8/d3-2005-2007/remont/cooling-fan/#42l-v8-5v-engine-mechanical-engine-codes-bfm)
2. Sealant

11 - Roller rocker lever

1. For exhaust camshaft
2. Removing and installing --> «Roller rocker lever, removing and installing»(/audi/a8/d3-2005-2007/remont/cooling-fan/#42l-v8-5v-engine-mechanical-engine-codes-bfm__roller-rocker-lever-removing-and-installing)

12 - Drive chain

1. Installing
2. Left cylinder head --> «Camshafts and camshaft adjusters (left cylinder head), removing and installing»(/audi/a8/d3-2005-2007/remont/cooling-fan/#42l-v8-5v-engine-mechanical-engine-codes-bfm__camshafts-and-camshaft-adjusters-left-cylinder)
3. Right cylinder head --> «Camshafts and camshaft adjusters (right cylinder head), removing and installing»(/audi/a8/d3-2005-2007/remont/cooling-fan/#42l-v8-5v-engine-mechanical-engine-codes-bfm__camshafts-and-camshaft-adjusters-right-cylinder)

13 - Roller rocker lever

1. For intake camshaft
2. Removing and installing --> «Roller rocker lever, removing and installing»(/audi/a8/d3-2005-2007/remont/cooling-fan/#42l-v8-5v-engine-mechanical-engine-codes-bfm__roller-rocker-lever-removing-and-installing)

14 - Intake camshaft

1. Checking axial play --> «Camshafts, checking axial clearance»(/audi/a8/d3-2005-2007/remont/cooling-fan/#42l-v8-5v-engine-mechanical-engine-codes-bfm__camshafts-checking-axial-clearance)
2. Removing and installing --> «Camshafts and camshaft adjusters (right cylinder head), removing and installing»(/audi/a8/d3-2005-2007/remont/cooling-fan/#42l-v8-5v-engine-mechanical-engine-codes-bfm__camshafts-and-camshaft-adjusters-right-cylinder)
3. Check radial play using Plastigage (cam follower removed) wear limit 0.1 mm, run-out max. 0.01 mm

15 - 5 Nm plus an additional 90° ( 1 / 4 turn)

1. Replace

16 - Mechanical camshaft adjuster

1. With Camshaft Adjustment Valve 1 N205
2. Before removing, secure using Bracket For Chain Adjustment 3366 --> «Camshafts and camshaft adjusters (right cylinder head), removing and installing»(/audi/a8/d3-2005-2007/remont/cooling-fan/#42l-v8-5v-engine-mechanical-engine-codes-bfm__camshafts-and-camshaft-adjusters-right-cylinder)

17 - Rubber/metal seal

1. Replace

18 - Valve keepers

19 - Valve spring plate

20 - Valve spring

21 - Valve stem seal

1. Replacing --> «Valve stem seals, replacing»(/audi/a8/d3-2005-2007/remont/cooling-fan/#42l-v8-5v-engine-mechanical-engine-codes-bfm) .

22 - Gasket

1. Replace

23 - Cylinder head

1. See note --> «Valvetrain, assembly overview»(/audi/a8/d3-2005-2007/remont/cooling-fan/#42l-v8-5v-engine-mechanical-engine-codes-bfm__valvetrain-assembly-overview)
2. Check valve guides, grind valve seats --> «Valve guides, checking»(/audi/a8/d3-2005-2007/remont/cooling-fan/#42l-v8-5v-engine-mechanical-engine-codes-bfm__valve-guides-checking)
3. Rework valve seats --> «Valve seats, reworking»(/audi/a8/d3-2005-2007/remont/cooling-fan/#42l-v8-5v-engine-mechanical-engine-codes-bfm__valve-seats-reworking)

24 - Exhaust valve

1. Do not rework, only lapping is permitted
2. Valve dimensions --> «Valve dimensions»(/audi/a8/d3-2005-2007/remont/cooling-fan/#42l-v8-5v-engine-mechanical-engine-codes-bfm)
3. Check valve guides, grind valve seats --> «Valve guides, checking»(/audi/a8/d3-2005-2007/remont/cooling-fan/#42l-v8-5v-engine-mechanical-engine-codes-bfm__valve-guides-checking)

25 - Intake valve

1. Do not rework, only lapping is permitted
2. Valve dimensions --> «Valve dimensions»(/audi/a8/d3-2005-2007/remont/cooling-fan/#42l-v8-5v-engine-mechanical-engine-codes-bfm)
3. Check valve guides, grind valve seats --> «Valve guides, checking»(/audi/a8/d3-2005-2007/remont/cooling-fan/#42l-v8-5v-engine-mechanical-engine-codes-bfm__valve-guides-checking)

26 - Seal

1. For Camshaft Position (CMP) Sensor
2. Replacing --> «Camshaft Position (CMP) Sensor seals, replacing»(/audi/a8/d3-2005-2007/remont/cooling-fan/#42l-v8-5v-engine-mechanical-engine-codes-bfm__camshaft-position-cmp-sensor-seals-replacing) .

27 - Cover for Camshaft Position (CMP) Sensor

1. Note installation location, notch in camshaft

28 - Washer

1. Conical

29 - 23 Nm

30 - Camshaft Position (CMP) sensor

31 - 10 Nm

32 - Shaft for roller rocker lever, intake side

1. Removing and installing --> «Roller rocker lever, removing and installing»(/audi/a8/d3-2005-2007/remont/cooling-fan/#42l-v8-5v-engine-mechanical-engine-codes-bfm__roller-rocker-lever-removing-and-installing)

33 - 10 Nm

34 - 10 Nm

35 - Shaft for roller rocker lever, exhaust side

1. Removing and installing --> «Roller rocker lever, removing and installing»(/audi/a8/d3-2005-2007/remont/cooling-fan/#42l-v8-5v-engine-mechanical-engine-codes-bfm__roller-rocker-lever-removing-and-installing)

36 - 55 Nm

37 - Camshaft sprocket

38 - Seal

1. For camshaft
2. Replacing --> «Camshaft seals, replacing»(/audi/a8/d3-2005-2007/remont/cooling-fan/#42l-v8-5v-engine-mechanical-engine-codes-bfm__camshaft-seals-replacing) .

39 - O-ring

1. For roller rocker lever shaft
2. Replace

Scheme 204

Note. Valves must not be reworked. Only lapping is permitted.

Scheme 205

1. Lightly coat hatched surface of double bearing cap as well as outer bearing cap next to camshaft adjuster with sealant and install bearing cap (observe alignment bushings).

1. Sealant