Porsche 944 Workshop Manual page 103

944
7. Ream the valve guides with
Special Tool 3120
Proceed as follows:
The valve guides must always be reamed with
"petroleum" lubricant Withdraw the reamer
regularly to remove chips. Then finish-ream
the boreagain with a dry reamer.
8. The valve seat rings must be remachined
alter replacing the valve guides. It is not
enough to grind in the valves with grinding
paste
Replacing the valve guides
Printed in Germany - XVII, 1988
Engine, Cylinder Head, Valve Drive
87/920
15
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