e e t 3 lI r w a y1t r r a y f i 7 h s i An 3s CYLINDER SEALING FACE u SURFACE V tJ U U U p 1 h Fig 6A 55 Cleaning Valve Bores Using Tool J 8101 NOTE If valve seat inserts or valve guides are beyond repair cylinder head replacement is necessary NOTE Excessive valve to bore clearance may cause lack of power oil consumption rough idling and noisy valves Insufficient clearance will result in noisy and sticky functioning of the valve and disturb engine smoothness of operation 4 Valve Stem clearance may be accurately determined by two methods a Micrometer and Telescope Gage Intake valve stem to bore clearance should be 001 to 0027 new and 001 to 004 worn while exhaust stem clearance should be 0015 to 0032 new and 002 to 005 worn Using a micrometer and a suitable telescope hole gage check the diameter of the valve stem in three places top center and bottom Insert telescope hole gage in valve guide bore measuring at the center Subtract highest reading of valve stem diameter from valve guide bore center diameter to obtain valve to guide clearance If clearance is not within 002 of above limits use next oversize valve and ream valve bore to fit b Using a Dial Indicator Intake valve stem to bore clearance should be 001 to 0027 new and 001 to 004 worn while exhaust stem clearance should be 0015 to 0032 new and 002 to 005 worn Using a Last Word Indicator clamp the indicator on one side of cylinder head rocker cover gasket rail arranging the indicator so that