Honda BF35A-BF45A Outboard Motors Shop Manual., Page 466Get this manual
6PROPELLER INSTALLATION
THRUST WASHER INSTALLATION Install with the groove side facing to the gear case
GEAR CASE
16 mm CROWN HEAD NUT
INSTALLATION 1.0 N-m (0.1 kgf-m, 0.7 Ibf-ft) If needed, tighten it to align the hole with grooveMaximum torque: 34.3 N-m (3.5 kgf-m, 25.3 Ibf-ft)