Valve Springs
Ensure valve spring free length, out-of-square and pressure are within specification. See VALVES & VALVE SPRINGS table under ENGINE SPECIFICATIONS. Replace valve spring if necessary.
NOTE:
Intake and exhaust valve stem seals are different. Exhaust seals can be identified by ridges molded into top of seal. Intake seals do not have identifying ridges. Incorrect installation of valve stem seals will cause premature failure.