4. Measure: margin thickness a Out of specification Replace. Margin thickness 0.80 ~ 1.20 mm (0.0315 ~ 0.0472 in) 5. Measure: valve stem runout Out of specification Replace. NOTE: _ When installing a new valve, always replace the valve guide. If the valve is removed or replaced, always replace the valve stem seal. 6. Eliminate: carbon deposits (from the valve face and valve seat) 7. Check: valve seats Pitting/wear Reface the valve seat. 8. Measure: valve seat width a Out of specification Reface the valve seat. Valve seat width 1.00 ~ 1.20 mm (0.0394 ~ 0.0472 in) : 1.60 mm (0.0630 in) MMM M M MMM M M MMM M M MMM M M MMM M M MMM M MMM a.
Apply Mechanic’s blueing dye (Dykem) b to the valve face. b. Install the valve into the cylinder head. c. Press the valve through the valve guide and onto the valve seat to make a clear pattern. d. Measure the valve seat width. Where the valve seat and valve face made contact, blueing will have been removed. 4 - 29 VALVES AND VALVE SPRINGS ENG Runout limit 0.040 mm (0.0016 in)