Porsche 928 Workshop Manual page 205

15
Engine/Cylinder Head, Valves 928
REPLACING VALVE GUIDES
1. Clean and inspect cylinder head. Cylinder
heads are not suitable for replacement of
valve guides, if their valve seats and
sealing surfaces can no longer be machined.
2. Machine off protruding valve guides from
the camshaft side with a countersink,
Special Tool 9220/l, until guides are flush
with the cylinder head.
Note:
Be careful not to damage guide collar for
spring retainers. 4. Loosen valve guides from camshaft end
with brief hammer knocks on Special Tool
9224 and press out rest of guides toward
combustion side with a press.
3. Place cylinder head on Special Tool 9220. 5. Check bores in cylinder head with an
internal gauge.
a
15-28
Replacing Valve Guides
Printed in Germany