Johnson Evinrude Outboard Motors 1956-1970 1.5-40hp repair manual., Page 66Get this manual
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First, soak the piston in container of very hot water for about ten minutesBefore pressing the wrist pin into place, hold the piston and rod near the cylinder block and check to be sure both will be facing in the right direction when they are installedPack the wrist pin needle bearing cage with needle bearing grease, or good grade of petroleum jellyLoad the bearing cage with needles and insert it into the end of the rodSlide the rod into the piston boss and check second time to be sure the slanted side of the piston is facing toward the exhaust side of the cylinder and the hole in the rod is facing upwardNow, assume sitting position and lay couple towels over your lapHold your legs tightly together to form cradle for the piston above your kneesSet the piston between your legs with the LOOSE side of the piston facing upwardNow, drive the wrist pin through the piston using drift pin with shoulderThe drift pin will fit into the hole through the wrist pin and the shoulder will ride on the end of the wrist pinUse sharp hard blows with hammerYour legs will absorb the shock without damaging the pistonIf this method is used on regular basis during the busy season, your legs will develop black-and-blue areas, but no problem, the marks will disappear in few daysContinue to drive the wrist pin through the piston until the groove in the wrist pin for the lockring is visible at both endsInstall the retaining spring wire or truarc ring onto each end of the wrist pin