2001 Mercury Mariner 50-60HP Factory Service Manual, Page 502Get this manual
BIGFOOT GEAR HOUSING
Pinion Gear Depth and Forward Gear Backlash
DETERMINING PINION GEAR DEPTH NOTE: Read entire procedure before attempting any change in shim thicknessIMPORTANT: Forward gear assembly pilots the end of the pinion gage and must be installed in gear housing when checking pinion gear depthWithout it an inaccurate measurement will be obtained1Clean the gear housing bearing carrier shoulder and diameter2With gear housing positioned up right (drive shaft vertical), install Bearing Preload Tool (91-14311A2) over drive shaft in sequence shown
-Adaptor: Bearing surfaces clean and free of nicks -Thrust Bearing: Oiled and able to move freely -Thrust Washer: Clean and free of nicks and bends -Spring -Nut: Threaded all-the-way onto bolt -Bolt: Held snug against spring -Sleeve: Holes in sleeve must align with set screws -Set Screw (2): Tightened against drive shaft, bolt should not slide on drive shaft