1991 Yamaha Outboard Factory Service Manual 9.9 and 15 HP, Page 55Get this manual
Crankshaft 1Lift the crankshaft bearings up off the crankcase by tapping on both ends of 2the crankshaft Hold down the cylinders and remove the crankshaft together with the pistons Piston pins and pistons 1Remove the piston pin clips from the piston2Remove the other piston pin-clips and push out the piston pin