A3 Mk2
Cylinder head, camshafts - exploded view |
1 - | 50 Nm + turn 180° further |
q | Renew |
2 - | Camshaft sprocket |
3 - | Oil seal |
q | Renewing → Chapter |
4 - | Cylinder head |
5 - | Valve guide |
q | Checking → Chapter |
6 - | Valve stem oil seal |
7 - | Valve spring |
8 - | Upper valve spring plate |
9 - | Cotters |
10 - | Hydraulic valve clearance compensation element |
q | Do not interchange |
q | Lubricate contact surface |
11 - | Parallel key |
q | Check for firm attachment |
12 - | Exhaust camshaft |
q | Check radial clearance with Plastigage (roller rocker fingers removed) |
q | Radial clearance when bearing Ø is 24 mm: 0.024 ... 0.066 mm |
q | Radial clearance when bearing Ø is 32 mm: 0.030 ... 0.051 mm |
q | Runout: max. 0.04 mm |
13 - | Retaining frame |
q | With integrated camshaft bearings |
q | Clean sealing surface; machining not permitted |
q | Remove old sealant residues |
14 - | 8 Nm + turn 90° further |
q | Renew |
15 - | Camshaft adjuster |
16 - | 20 Nm + turn 45° further |
q | Renew |
17 - | Inlet camshaft |
q | Check radial clearance with Plastigage (roller rocker fingers removed) |
q | Radial clearance when bearing Ø is 24 mm: 0.024 ... 0.066 mm |
q | Runout: max. 0.04 mm |
18 - | Chain tensioner |
19 - | Drive chain |
20 - | 10 Nm |
21 - | 10 Nm |
22 - | Phase sensor |
23 - | Exhaust valve |
q | Do not machine, only grinding-in is permitted |
q | Valve dimensions → Fig., |
q | Checking valve guides → Chapter |
24 - | Inlet valve |
q | Do not machine, only grinding-in is permitted |
q | Valve dimensions → Fig., |
q | Checking valve guides → Chapter |
25 - | Sealing cap |
q | Renew |
q | Removing sealing cap with retaining frame installed: pierce on one side with an awl and pry out |
q | Installing: press in 1 ... 2 mm deep without sealant using thrust piece -3334- |
Note
|
Dimension | Inlet valve | Exhaust valve | |
Ø a | mm | 33.85 ± 0.10 | 28.0 ± 0.1 |
Ø b | mm | 5.98 ± 0.01 | 5.96 ± 0.01 |
c | mm | 104.0 ± 0.2 | 101.9 ± 0.2 |
α | ∠° | 45 | 45 |