Valve Gear, Servicing

Valve gear, servicing
1. 5 Nm + 1/8 turn (45°) further
2. Exhaust camshaft bearing cap
3. Seal
^ Replace complete if leaking
^ Oil contact surfaces of seal lightly when installing control housing
^ Spread/stretch seal as little as possible when replacing
^ Offset gaps by 120°
4. Exhaust camshaft
^ Check radial clearance with Plastigage, Wear limit: 0.1 mm
^ Run-out: max. 0.01 mm
^ Checking axial clearance, Refer to Fig 1
^ Identification and valve timing, Refer to Fig 5
5. Control housing
^ Lightly lubricate contact surfaces of oil seal when installing
^ Check screen of control housing for soiling before installing
^ Removing and installing, Refer to Timing Cover, Service and Repair
6. Camshaft roller chain
^ Mark direction of rotation before removing (installation position)
7. Exhaust camshaft timing adjuster
^ Marking: 32A
^ Turn engine over only when camshaft timing adjuster is installed
^ Checking camshaft timing adjustment, Refer to Camshaft, Engine, Adjustments
^ Installing, Refer to Timing Components, Adjustments
8. 60 Nm + 1/4 turn (90°) further
^ Replace
^ Contact surface of sensor wheel on bolt head must be dry for assembly
^ To remove and install, use a 32 mm open end wrench on camshaft to counter support, Refer to Camshaft, Engine, Removing and Installing
9. Intake camshaft timing adjuster
^ Markings: 24E
^ Turn engine over only when camshaft timing adjuster is installed
^ Checking camshaft timing adjustment, Refer to Camshaft, Engine, Adjustments
^ Installing, Refer to Timing Components, Adjustments
10. Cylinder head height
^ Minimum height: a = 139 9 mm
11. Valves
^ Do not rework, only lapping-in is permitted
^ Valve dimensions, Refer to Fig 4
12. Cylinder head
^ Check for distortion, Refer to Cylinder Head, Service and Repair, Cylinder Head, Servicing,See Fig 1
^ Reworking valve seats, Refer to Valve Seat, Service and Repair
^ After replacement replace the entire coolant
13. Support element
^ Check axial clearance of camshaft before installation
^ Do not interchange
^ With hydraulic valve clearance compensation
14. Valve stem seal
^ Refer to Seals and Gaskets, Engine, Valve Guide Seal, Service and Repair
15. Retaining clip
^ Check seated securely
16. Roller rocker finger
^ Check axial clearance of camshaft before installation
^ Do not interchange
^ Check roller bearing for easy movement
^ Oil running contact surfaces
^ Use securing clip to clip onto support element when installing
17. Valve spring
18. Valve spring plate
19. Valve coffers
20. Inlet camshaft bearing cap
^ Before installing bearing cap 7, lightly grease the contact surfaces with G 052 723 A2, Refer to Fig 2
^ Installation position, Refer to Fig 3
^ Installation sequence, Refer to Camshaft, Engine, Service and Repair
21. Intake camshaft
^ Check radial clearance with Plastigage, Wear limit: 0.1 mm
^ Run-out: max. 0.01 mm
^ Checking axial clearance
^ Identification and valve timing, Refer to Fig 5
^ Removing and installing, Refer to Camshaft, Engine, Service and Repair





Fig. 1 Camshafts, checking axial clearance
Special tools and equipment
^ VW 387 Universal dial gauge bracket
^ Dial gauge

Test sequence
Perform measurements with support elements and roller rocker fingers removed.

Intake camshaft
- Install bearing cap 7 and tighten to 5 Nm and 1/8 turn (45°).
Wear limit: max. 0.10 mm

Exhaust camshaft
- Install bearing cap 8 and tighten to 5 Nm and 1/8 turn (45°).
Wear limit: max. 0.10 mm





Fig. 2 Greasing contact surfaces of bearing caps 7 and 8 lightly with G 052 723 A2 before installing
Special tools and equipment
^ G 052 723 A2 Grease

Work sequence
- Before installing, lightly grease contact surfaces on both sides of bearing caps 7 and 8 (hatched areas only) with grease G 052 723 A2.





Fig. 3 Installation position of camshaft bearing caps
Points of bearing caps -arrow A- of intake and exhaust camshafts face outward.
Identifications on bearing caps are legible when read from intake side.





Fig. 4 Valve dimensions

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





Valve dimensions for intake valves





Valve dimensions for exhaust valves





Fig. 5 Camshaft identification, valve timing
Camshaft identification





Identification between No. 4 cyl and No. 5 cyl cam pair of respective camshaft.





Valve timing at 1 mm valve lift





Fig. 6 Disassembling and assembling control housing
1. Guide rail: Clipped onto control housing
2. Control housing:
Replaced complete with Valve 1 for camshaft adjustment -N205- and Camshaft adjustment valve 1 (exhaust) -N318-.
3. Valve 1 for camshaft adjustment -N205
4. Camshaft adjustment valve 1 (exhaust) -N318
5. 8 Nm: Replace (4 securing bolts)





Fig. 7 Checking control housing screen for soiling
- Unclip screen -2- out from rear side of control housing -1- and clean if necessary.