Skoda OCTAVIA MK1 Service Manual page 82

distance measured -a-
- Minimum dimension
= Max. permissible reworking dimension
Note
If the max. permissible reworking dimension is 0 mm, repeat measurement with a new valve.
If the max. permissible reworking dimension is again 0 mm, replace cylinder head.
Reworking valve seats
Dimension
Ø a
b
c
Z
45°
30°
Procedure
Reworking can be carried out with a machine or by hand. The following conditions must be
met:
l Wear limit of valve guides must not exceed the permissible dimension
l Use NAC milling cutter with carbide metal tips (min. 90 HRC).
mm Valve seat diameter
mm
mm Valve seat width
Valve seats
39.2 -0.1 - inlet valve
32.4 -0.1 - exhaust valve
Max. permissible reworking dimension
1.9 up to 2.1 - inlet valve
2.3 up to 2.5 - exhaust valve
Bottom edge of cylinder head
Valve seat angle
Top correction angle
82
34.5 mm
33.8 mm
0.7 mm
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