Volkswagen Workshop Service and Repair Manuals

Valve control mechanism - repair   Note t  Cylinder heads with cracks between the valve seats or between a valve seat ring and the spark plug thread can remain in use without loss of durability, provided that the cracks are small, no wider than 0.3 mm, or when only the first 4 threads are damaged. t  After new tappets have been assembled, the engine should not be started for approximately 30 minutes. (otherwise, the valves may interfere with the piston). Then, turn the crankshaft two turns.

1 -

100 Nm

q	To remove and install, use the Spanner -3415 -.

2 -	Camshaft gear

3 -	Sealing ring

q	Replace → Chapter.

4 -

Key

q	Check firm fitting.

5 -

20 Nm

6 -	Bearing cover

q	Assembly position → Fig.

q	Assembly sequence → Chapter.

q	Grease the support surface of bearing cover 1 with the Sealing putty -AMV 174 004 01-.

7 -

Camshaft

q	Check axial clearance → Fig.

q	Remove and install → Chapter.

q	Measure radial clearance with “Plastigage”: Wear limit: 0.1 mm.

q	Runout: max. 0.05 mm.

8 -	Hydraulic tappet

q	Do not invert.

q	With valve clearance hydraulic offsetting.

q	Check → Chapter.

q	Place with the contact surface facing down.

q	Check camshaft axial clearance before installing → Fig.

q	Lubricate contact surfaces.

9 -

Keys

10 -	Upper plate of valve springs

11 -	Valve spring

q	Remove and install: Cylinder head removed: with the Compressor device -2037- installed: → Chapter.

12 -	Valve rod oil seal

q	Replace → Chapter.

13 -	Valve guide

q	Check → Chapter.

q	Repair guide with shoulder.

14 -	Cylinder head

q	Rework the sealing surface → Fig.

q	Grind valve seats → Chapter.

15 -

Valves

q	Do not grind; only seating is permitted.

q	Valve measures → Fig.

Rework the sealing surface of the cylinder head Cylinder head grinding elevation: -a- = at least 132.6 mm.   Note In case of grinding of the cylinder head, the valve seats must be ground by the same measure.

Check camshaft axial clearance Special tools and workshop equipment required t  Support -VW 387- t  Dial gauge Measure with tappets removed and the first and last bearing caps mounted. Wear limit: max. 0.15 mm.

Assembly position of the camshaft bearing cap Observe runout. Before installing the camshaft, place bearing caps and find the right assembly position. Camshaft identification

Identification between cam pairs, intake and exhaust valve of cylinder 1
Cylinder 1 (BBX engine)	050 P
Cylinder 1 (CFEA engine)	06A M

Valve measures   Note Valves may not be ground. Only seating is permitted.

Measure		Intake valve	Exhaust valve
Ø a	mm	39,5 ± 0,15	32,9 ± 0,15
Ø b	mm	6,98 ± 0,007	6,96 ± 0,007
c	mm	91,85	91,15
α	∠°	45	45

Distribution times for 1-mm valve clearance (BBX/CFEA)

		Intake valve	Exhaust valve
Then opens	TDC	6,2°	--------
Then closes	BDC	42,45°	--------
Opens before	BDC	---------	35,8°
Then closes	TDC	---------	0,45°