1999 "EE" Evinrude 70HP 4-Stroke Service Manual, P/N 787023, Page 121Get this manual
DRC7533 DRC7534 DRC7535
5Inspect valve guides for contamination, excessive wear, or damageThoroughly clean all carbon deposits from valve guidesIf guides are replaced, seats must be reground0.05-0.06 in(1,3-1,5 mm)
6A reputable machine shop is recommended to perform valve guide replacementUse the specifications noted in reference drawingReam guides after installation
[] 7Inspect valves and valve seats for contamination, excessive wear, or damageThoroughly clean all carbon deposits from intake and exhaust seatsValve seats should be concentric to within 0.002 in(0,05 mm)
8To determine if valve seats need grinding, check wear pattern on valvesService seats if wear pattern is too wide or too narrow Use the specifications noted in reference drawings