Valve Gear, Repairing

Note: If cracks are small, and no more than 0.5 mm wide, cylinder heads with cracks between the valve seats or between the valve seat ring and the spark plug thread can continue to be used without a reduction in life.

1. Bearing cover
- Installation position see Fig. 2
2. 20 Nm
3. Camshafts
- Checking axial clearance see Fig. 1
- Check radial clearance using Plastigage. Max. wear: 0.10 mm
- Runout: max. 0.01 mm
4. Camshaft sprocket
5. Pickup wheel
- For Hall generator (G40)
- Contact area at camshaft sprocket and pickup wheel must be dry during installation
6. 100 Nm
- Place against camshaft using fork wrench SW 24 for removal and installation page 1534
- Oil screw head contact area during installation
7. Cylinder head height
- Min. height: a = 139.5
8. Cylinder head
9. Valves
- Do not finish, only grinding is allowable
- Valve measurements see Fig. 3
10. Valve guide
- Repair guide with collar
11. Valve stem seal
12. Valve springs
- Removing and installing:
- With cylinder head removed: use 2037
13. Valve spring retainer
14. Valve collets
15. Valve lifters
- Do not mix up
- With hydraulic valve clearance balancing
- For storage, lay down with the running face facing down
- Prior to installation, check camshaft axial clearance see Fig. 1





Fig. 1 Camshafts, checking axial clearance
Special tools, equipment, test and inspection devices; required accessories
- Universal gauge retainer VW 387
- Gauge

Test procedure
Max. wear: 0.15 mm
Measure with valve lifters removed and first and last bearing cover of each camshaft installed.





Fig. 2 Installation position camshaft bearing cover
The bearing cover markings (arrows) must point toward the oscillation damper side.





Fig. 3 Valve measurements

Note: Do not machine valves, only lapping is permissible.





Specifications