Volkswagen Workshop Service and Repair Manuals

Repairing valve gear

t

Cylinder heads which have cracks between the valve seats or between a valve seat insert and the spark plug thread can be used further without reducing service life, provided the cracks do not exceed a maximum of 0.3 mm in width, or when no more than the first 4 turns of the spark plug thread are cracked.

t	Wait about 30 minutes after installing the new tappets before starting the engine. (Otherwise valves will strike pistons), then turn crankshaft by 2 complete revolutions.

1 -

100 Nm

q	Use counterhold tool -3415- to loosen and tighten.

2 -	Camshaft pulley

3 -

Seal

q	Renew → Chapter.

4 -	Woodruff key

q	Check for secure seating.

5 -

20 Nm

6 -	Bearing cap

q	Installation position → Fig..

q	Fitting sequence → Chapter, remove and install camshafts.

q	Apply light coating of sealing compound -AMV 174 004 01- to contact surface of bearing cap 1.

7 -

Camshaft

q	Check axial clearance → Fig..

q	Remove and install → Chapter.

q	Check radial clearance with Plastigage. Wear limit: 0.1 mm.

q	Runout: max. 0.05 mm.

8 -

Tappet

q	Do not interchange.

q	With hydraulic valve clearance adjustment.

q	Check → Chapter.

q	Place to side with running surface pointing down.

q	Before fitting, check camshaft axial clearance → Fig..

q	Oil running surface.

9 -

Cotters

10 -	Upper valve spring plate

11 -	Valve spring

q	Remove and install: with cylinder head removed: install using valve spring depressor -2037- → Chapter.

12 -	Valve stem seal

q	Renew → Chapter.

13 -	Valve guide

q	Check → Chapter.

q	Renew → Chapter.

q	Repair guide with collar.

14 -	Cylinder head

q	Rework sealing surface → Fig..

q	Rework valve seats → Chapter.

15 -

Valves

q	Do not rework. Only lapping in is permitted.

q	Valve dimensions → Fig..

Reworking sealing surface Rework dimension of cylinder head: a = minimum 132.6 mm   Note If sealing surface is reworked, all valves must be deeper by same dimension.

Checking camshaft axial clearance Special tools and workshop equipment required t  Universal dial gauge bracket -VW 387- t  Dial gauge Measure with tappets removed and with first and last bearing caps fitted. Wear limit: max. 0.15 mm.

Installation position of camshaft bearing cap Note centre offset. Before installing camshaft, fit bearing cap and locate installation position.

Valve dimensions   Note Do not rework valves. Only lapping-in is permitted.

Dimension		Inlet valve	Exhaust valve
Ø a	mm	39.5 ± 0.15	32.9 ± 0.15
Ø b	mm	6.98 ± 0.007	6.965 ± 0.007
c	mm	91.85	91.15
α	∠°	45	45