Honda Outboards BF40A/BF50A Service Manual, Page 107Get this manual
HONDA BF3!5A4!5A
INSPECTION
VALVE SPRING FREE LENGTH
Measure the free length of the valve springsSTANDARD SERVICE LIMIT
36.9 mm (1.45 in)
35.4 mm (1.39 in)
Replace the springs if they are shorter than the service limit
VALVE STEM 0.0Inspect each valve for face irregularities, bending or abnormal stem wearReplace the valve if necessaryMeasure and record each valve stem 0.0STANDARD IN EX SERVICE LIMIT
5.480-5.490 mm (0.2157-0.2161 in) 5.460-5.470 mm (0.2150-0.2154 in)
5.45 mm (0.215 in) 5.42 mm 0.213 in)