Valve Gear, Servicing

Valve gear, servicing

Note:
- Cylinder heads which have cracks between the valve seats or between valve seat inserts and the spark plug thread can be used further without reducing service life, provided the cracks do not exceed a maximum of O.3 mm in width, or when no more than the first four spark plug threads are cracked.
- When new lifters have been installed the engine must not be started for about 30 minutes. (Otherwise valves will contact pistons) First, rotate crankshaft two complete revolutions.

Assembly overview





Engines: AEG, AVH, AZG, APK, AQY, BEJ, BER, BEV, BHP

1. 100 Nm
- Use counterhold 3415 to loosen and tighten
2. Camshaft sprocket
3. Seal
4. Woodruff key
- Check for secure seating
5. 20 Nm
6. Bearing cap
7. Camshaft
- Check radial clearance with Plastigage, Wear limit: 0.1 mm
- Run-out: max. 0.05 mm
8. Hydraulic lifter
9. Keepers
10. Valve spring upper plate
11. Valve spring
12. Valve stem seal
13. Valve guider
14. Cylinder head
15. Valves





Engine: BBW

1. Camshaft sprocket
- With camshaft timing adjustment
- Under no circumstances should bolts be loosened.
- Replace complete
2. Seal
- To remove and install, remove bearing cap
- Do not oil sealing lips of sealing ring.
3. 20 Nm
4. Bearing cap
- Coat contact surfaces of bearing cap 1 lightly with sealing compound AMV 174 004 01.
5. Camshaft
- With sender wheel for camshaft position sensor
- Checking axial clearance, Refer to Fig.2
- Check radial clearance with Plastigage, Wear limit: 0.1 mm
- Run-out: max. 0.05 mm
6. Hydraulic lifter
- Store with cam contact surface downward
- Before installing check camshaft axial clearance, Refer to Fig. 2
- Oil contact surface
7. Keepers
8. Valve spring upper plate
9. Valve spring
10. Valve stem seal
11. Valve guide
12. Cylinder head
- Reworking sealing surface, Refer to Fig. 1
13. Valves
- Do not rework, only lapping is permitted
- Valve dimensions, Refer to Fig. 4
14. Filter element
- Pull off with hooks
- Clean if soiled
15. Sealing plug, 12 Nm
- Always replace
16. 130 Nm
- To loosen and tighten use counter-bracket T101 72 with pin T101 72/3.
17. O-ring
- Always replace
18. Sealing plug, 25 Nm





Fig. 1 Reworking cylinder head sealing surface

Cylinder head reworking dimension:
a = At least 132.6 mm

Note: When the sealing surface has been reworked, the valves must be set deeper by the same amount.

Fig. 2 Checking camshaft axial clearance
Special tools, testers, measuring instruments and auxiliary items required





- Universal dial gauge bracket VW 387
- Dial gauge
- Check with hydraulic lifters removed and with first and last bearing caps installed.
- Wear limit: max. 0.15 mm





Fig. 3 Installed position of camshaft bearing caps

Note offset. Before installing camshaft determine position.








Fig. 4 Valve dimensions

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