W350 1 Ton Pickup 4WD V8-360 5.9L VIN 1 4-bbl (1988)
Valve Guide: Service and Repair
VALVE GUIDES
These engines do not have removable valve guides. The valves operate in guide holes bored in the cylinder head. Valves with oversize valve stems are
available for service replacement when necessary to ream the guide holes.
Standard production stem diameter should be .372-.373 inch for intake valves and .371-.372 inch for exhaust valves. If stem wear exceeds .002 inch,
replace valve. When reaming guides for oversize valve stems do not attempt to ream from standard to .030 inch oversize. If necessary to ream to that
size, use the step procedure of .005 inch, .015 inch and .030 inch. This must be done in order to maintain a true relationship of the guide to the valve seat
. The following chart indicates reamer size and valve stem size.
REAMER OVERSIZE VALVE STEM SIZE
.005 inch .379-.380 inch
.015 inch .389-.390 inch
.030 inch .404-.405 inch