1983 Yamaha 30EN Outboards Service Manual, Page 117Get this manual
7By turning the drive shaft clockwise, install the water pump housing, and secure with three bolts GEAR CASE INSTALLATION 1Check that the clutch dog shifts to "Forward", "Neutral", "Reverse" correctly by pulling or pushing the shift cam, and shift into "Reverse"2Set shift rod (on the engine side) to Reverse3Install the gear case to the upper caseMake sure that the drive shaft splines firmly fit into the crankshaft splines and that the water tube fits firmly into the water pumpNOTE: _ The drive shaft splines and crankshaft must be lubricated before assemblyLubricating gear oil Add hypoid gear oil #90 through the oil drain plug hole until the oil flows out of the oil level plug holeOil capacity 180 cm (cc) 6.34 Imp OZ, 6.1 US oz