Valve Stem Oil Seals
Oil seals must be replaced whenever valve service is performed. Lightly coat valve stems with engine oil. Push seals firmly and squarely over guide so center bead of seal seats in groove on valve guide and lower edge of seal rests on valve guide boss. If oversize valves are used, oversize seals must be installed.
NOTE:
Excessive valve guide wear may result if oversize seals are not used with oversize valves.