Bronco L6-300 4.9L VIN Y 1-bbl (1983)
Valve Guide: Service and Repair
Valve guides in these engines are an integral part of the head and, therefore, cannot be removed. For service, guides can be reamed oversize to
accommodate one of three service valves with oversize stems (.003 inch, .015 inch and .030 inch).
Check the valve stem clearance of each valve (after cleaning) in its respective valve guide. If the clearance exceeds the service limits of .004 inch of
the intake or .005 inch on the exhaust, ream the valve guides to accommodate the next oversize diameter valve.
