Mercury Mariner Outboard 225 3 Litre Service Manual 1994, Page 256Get this manual
Drive ShaftBearing Preload Tool REMOVAL
Place the bearing carrier assembly into the gear housingIt may be necessary to turn the drive shaft to align the teeth of the pinion and the reverse gears
CAUTION
Before loosening the top nut allen screws of the bearing preload toolscrew the bottom nut up as close as possible to the top nut12
Remove the dial indicator and its supporting toolingScrew the bottom nut of the bearing preload tool until it is as close as possible to top nutLoosen the allen screws in the top nut
4Remove all components including the water pump face plate
aBearing Carrier Assembly
Align the bearing carrier "V' shaped notch with the alignment hole in the gear housing and then install the tab washer with the external tab inserted into the hole in the gear housing