6- and 8-cylinder petrol engines on the Audi A4

Basic information

Engines DOHC 2.4, 3.0, 4.2 l - V-shaped, with a cylinder angle of 90 °, respectively, 3 and 4 cylinders in a row. Such engines are designated V6 and V8.

The engines have three intake and two exhaust valves per cylinder. Each row of engine cylinders has 2 camshafts. On the V6 engine, the exhaust camshafts are driven by a toothed belt, the intake camshafts are driven by a chain from the exhaust camshafts. The V8 engine has four camshafts, as well as auxiliary units, driven by several chains. The drive chains are located on the flywheel side (gearbox side).

Cylinder block, crankshaft and flywheel of a V6 engine

1. Crankshaft End play check: New: 0.07 - 0.23 mm Wear limit: 0.25 mm Radial clearance check with Plastigage: 0.018 - 0.045 mm Wear limit: 0.10 mm  Caution:  Do not rotate the crankshaft when checking the radial clearance. 
2. Main bearing cap 4 with thrust washer recess 
3. Bolt. Replace,  60Nm+90 °. To measure the radial clearance, tighten the bolt to a maximum of  60Nm 
4. Main bearing thrust washer 4 
5.  Flywheel/Drive Disc 
6.  Flywheel/drive plate bolt. Replace, (flywheel  60Nm+180 °), (drive plate  60Nm+90 °). When releasing, use tool 3242 to lock the crankshaft 
7. Inserts of main bearings. Do not mix up removed earbuds 
8. Sealed flange with stuffing box. Replaced as an assembly. Drain coolant before removing 
9. Pad. Replace 
10. Bolt,  10Nm 
11. Cylinder block thrust washer, bearing 4 
12. Bolt,  25Nm . Pre-tighten by hand before tightening the main bearing cap bolts 
13. Cylinder block 
14. Guide bush 

The main elements of the timing drive of the V6 engine

1. Bolt,  55Nm 
2. Toothed belt tensioner. Lock with tool 3204 before removing 
3. Upper right timing belt cover 
4. Center right toothed belt cover 
5. Toothed belt. Before removing, mark the direction of belt movement. Check for wear. Don't go overboard 
6. Top left toothed belt cover 
7. Bolt,  25Nm 
8. Bolt, 25Nm
9. Washer 
10. Bearing sleeve 
11. Toothed belt tensioner 
12. tension lever 
13. Sealing ring 
14. Bolt,  25Nm 
15. bracket 
16. Connection (thermostat housing) 
17. Water pump 
18. Oil pump 
19. cylinder head 
20. crankcase breather housing 
21. Cylinder block 
22. Bolt,  45Nm 
23. bracket 
24. Oil pan 
25. guide roller 
26. Bolt,  45 Nm 
27. crankshaft gear 
28. Bolt  200Nm+180 °, replace 
29. Belt tensioner 
30. Bolt,  10Nm  . Install with D6 grease 
31. Fan pulley 
32. Bolt M8 -  25Nm  , M6 -  10Nm 
33. Timing belt cover 
34. Bolt,  10Nm 
35. Vibration damper 
36. Bolt,  25Nm 

Chain drive for intake camshaft. V6 engine

1. Upper right timing belt cover 
2. Center right toothed belt cover 
3. Top left toothed belt cover 
4. Hex nut,  10Nm 
5. Rear Timing Belt Cover 
6. lifting eye 
7. Bolt,  25Nm 
8. Cylinder head cover gasket. Replace if damaged. Lubricate the gasket surface between the bearing cover and the cylinder head with grease D 454 300 A3 before installation. 
9. cylinder head cover 
10. pad 
11. Lid. Replace seal if damaged 
12. bracket 
13. Hexagon nut,  10Nm . Tighten from center outwards 
14. Cylinder head bolt. Replace 
15. Cylinder head. Check flatness 
16. Oil deflector 
17. Cylinder head gasket (metal). Replace 
18. Crankshaft gear 
19. clamping plate 
20. Bolt,  55Nm

Elements of the cylinder head. V6 engine

1. Double bearing cover. Lightly lubricate the mating surface with grease AV 174 004 01 
2. Bolt,  10Nm 
3. Exhaust camshaft bearing caps. Lightly lubricate the mating surfaces of the outer (outer) bearings with grease AV 174 004 01 
4. Exhaust camshaft. Radial clearance check with Plastigage: Run-out max: 0.01 mm Wear limit: 0.10 mm 
5. Cap. Replace. To remove, remove the bearing cap. With the bearing cap installed, press on with tool 3202 and a plastic mallet. 
6. Inlet camshaft bearing caps 
7. Exhaust camshaft 
8. Camshaft adjuster. Lock the chain tensioner with lock 3366 before removing. Check camshaft adjustment 
9. Drive chain. Before removing, mark the direction of travel 
10. Bolt,  10Nm 
11. Sealing ring. Replace 
12. Valve 1 or 2 for adjusting the camshaft N205 or N208. Check camshaft adjustment
13. Gasket (rubber/metal). Replace 
14. segment insert. Replace 
15. Hydraulic valve lifter. Do not interchange tappets of different valves. Store down the contact surface with the camshaft cam 
16. Split lock crackers 
17. valve spring holder 
18. valve spring 
19. Oil deflector cap 
20. Valve lifter rod 
21. cylinder head 
22. valves 
23. Stuffing box. Lightly lubricate the seal lips 
24. damper CMP 
25. conical washer 
26. Bolt,  25Nm 
27. Camshaft position sensor (CMP) 
28. Bolt,  10Nm 
29. Guide bush

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