1985 Mercury Outboard V-300 V-3.4L Shop Service Manual, Page 177Get this manual
6Reach into gear housing and remove pinion gear7Remove shim (s) (if equipped) from below dri ve shaft tapered roller beari ng hHemove dri ve shaft needle bearing by st riking Driver Hod with malletIMPORTANT: Discard drive shaft needle bearing after removal(Bearing cannot be re-used
CLEANING and INSPECTION
IClean dri ve shaft ,tapered bearing and race, and pinion gear wit solventDr with compressed airDO NOT spin dr shaft bearing2Inspect pinion gear for pittinggroovesscoring, uneven ""ear, and discoloration fr om overheat ingReplace pinion gear, if ny of the above conditions are found 3Inspect dri ve shaft needle bearing surface (area jusl above pi nio gear spl ines) for pitting, groovesscoringuneven wearando discolora tion from overheatingReplace drive shaft and drive shaft needle bea ring, if any of the preceding cond itions are found4Inspect drive shaft to crankshaft splines for wearReplace drive sha ft if wear is excessive5Inspect tapered bearing race for pittinggroovesscoring uneven wear, and di scoloration fro ove rh eatingReplace tapered bearing and race as setif any of th preceding conditions are found6Inspect water pump base oil seal urface fo groovesRe place drive shaft if grooves are fou nd