SEAT Workshop Service and Repair Manuals

Repair the valve mechanism

The cylinder heads which show cracks between valve seats or between a valve seat ring and the threads of a spark plug can continue to be used without affecting its useful life if the cracks are minor, with a maximum width of 0.5 mm or if only the first rings of the spark plug thread are affected.

1 -

10 Nm

2 -	6 Nm + turn 1/4 (90°) rotation more

3 -	Bearing cover

q	Position and order of the assembly → Chapter, disassemble and assemble the camshaft

q	Lightly cover the bearing 1 and 5 coverings with the waterproofing agent -AMV 174 004 01-

4 -

Camshaft

q	Check the axial play → Fig.

q	Disassemble and assemble → Chapter

q	Check the radial play with plastigage Wear limit: 0.1 mm

q	Impact: max. 0.01 mm

q	Marks and control timing → Fig.

5 -	Flat-type tapped

q	Do not confuse

q	Check the valve play with hydraulic compensation → Chapter

q	Install with the rolling surface downward

q	Before assembly check the axial play of the camshaft → Fig.

q	Lubricate the rolling surface

6 -	Conical parts

7 -	Valve spring plate

8 -	Valve spring

q	Disassemble and assemble: cylinder head disassemble: with -2037- assemble: → Chapter, replace the valve stem gaskets

9 -	Valve guide repair

q	With connection

10 -	Calve stem gasket

q	Replace → Chapter

11 -	Valve guide

q	Check → Chapter

q	Replace → Chapter

12 -	Sealing ring

q	Lightly lubricate the sealing ring fold

q	Replace → Chapter

13 -	Cylinder head

q	Retouch the valve seating → Chapter

q	Retouch the hermetic surface → Fig.

14 -

Valves

q	It is not necessary to retouch, only rectify

q	Valve measurements → Fig.

15 -

20 Nm

16 -	Attachment ring

17 -

Halter

q	For ignition guide cable

Retouch the hermetic surface of the cylinder head Measurement of the cylinder head retouch: a = at least 135,6 mm   Note! If the hermetic surface is adjusted, the valves must be positioned as seen below (adjust the valve seating rings). If not, the valves would touch the piston. Be sure that they are not below the minimum authorised measurement → Chapter

Camshaft, check the axial play Special tools and workshop equipment required t  Universal display support -VW 387- t  Clock display When measurements are taken, the flat-type tappets should be disassembled and the cover of bearing 3, assembled. Wear limit: max. 0.15 mm

Marked from the camshaft, control timing

Engine code letters	AER	AEX
Between the inlet and exhaust cam cylinder 1 -arrow-	030 BG	030 AM
Marked from the ring	without	1 and 2

Control timing with 1 mm stroke of the valve

Engine code letters	AER	AEX
Inlet opens after OT	10°	10°
Inlet closes after UT	27°	27°
Exhaust opens before UT	34°	27°
Exhaust closes before OT	10°	10°

Valve dimensions   Note! It is not necessary to adjust the valves. Only grinding is admitted. Engine code letters AER

Dimension		Inlet valve	Exhaust valve
Ø a	mm	31.0	26.0
Ø b	mm	6.967	6.943
c	mm	94.8	94.45
α	∠°	45	45

Engine code letters AEX

Dimension		Inlet valve	Exhaust valve
Ø a	mm	35.6	29.0
Ø b	mm	6.967	6.943
c	mm	94.8	95.0
α	∠°	45	45