Mercury Mariner V-250 V-275 Outboard Service Shop Manual 1990, Page 241Get this manual
5Removethrust bearing and spacershimInspect thrust bearing for pitsrustor discoloration (blueing) due to lack of lubricantRemove thrust bearing and thrust washer from bearin adaptorThrust roller bearing should be inspected fe pittingrust or signs of discoloration (blueing) due lack of lubricantIf thrust roller bearing must be re placed, the bearing surfaces on the thrust washer an, propeller shaft where the thrust roller bearing ride should also be inspected for signs of wear
aForward GearForward Gear Clutch TeethForward Gear TeelhForward Gear HubThrust BearingSpacer Shim
aThrust BearingThrust WasherBearing Adaptor
Remove thrust washer and O-ringThe thrust washer acts as bearing surface for the thrust bearing and it should be inspected for pits, rust, scoring or discoloration due to lack of lubricantO-ring should be inspected for cuts or abrasions and replaced if necessary