Camshaft, Lifters and Push Rods: Service and Repair

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) Then, finally, rotate crankshaft two complete revolutions.





1. 100 Nm
^ Use counter support tool 3415 to loosen and tighten
2. Camshaft pulley
3. Seal
4. Woodruff key
^ Check if seated securely
5. 20 Nm
6. Bearing cap
^ Coat contact surfaces of bearing cap 1 lightly with sealing compound AMV 174 004 01.
7. Camshaft
^ Checking axial clearance; Refer to Fig. 2
^ Check radial clearance with Plastigage, Wear limit: 0.1 mm
^ Run-out: max. 0.05 mm
8. Hydraulic lifter
^ Do not interchange
^ With hydraulic valve clearance compensation
^ Store with cam contact surface downward
^ Before installing check camshaft axial clearance; Refer to Fig 2
^ Oil contact surface
9. Keepers
10. Valve spring upper plate
11. Valve spring
12. Valve stem seal
13. Valve guide
14. Cylinder head
^ Reworking sealing surface; Refer to Fig 1.
15. Valves
^ Do not rework, only lapping is permitted
^ Valve dimensions; Refer to Fig 4





Fig. 1 Reworking cylinder head sealing surface
Cylinder head reworking dimension: -a- = min. 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 VW387
^ 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 fit bearing caps and determine installed position.





Fig. 4 Valve dimensions

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





Engine code AEG





Engine codes AVH, AZG, BDC, BEV, BGD