2006 SD Johnson 4 Stroke 9.9-15HP Outboards Service Manual, Page 148Get this manual
POWERHEAD CYLINDER HEAD ASSEMBLY Measure valve seat contact width as follows: Coat valve seat evenly with Prussian Blue Install valve into valve guide Put valve lapper on valve Rotate valve while gently tapping valve contact area against seat Repeat until continuous pattern in the Prussian Blue is seen Measure valve seat contact width: Service limit: 0.035 to 0.043 in(0.9 to 1.1 mm) If measurement exceeds service limit, repair valve seatRefer to Valve Seat Servicing on p149004541
Valve Spring
Measure valve spring free lengthIf measurement is lower than service limit, replace valve spring Standard: 1.280 in(32.52 mm) Service limit: 1.276 in(32.40 mm)