Mercury Mariner 4, 5 102CC Sail 1990 Outboard Service Shop Manual, Page 99Get this manual
Cleaning and Inspection Gear Housing Bearing Carrier Castings
1Thoroughly clean gear housing bearing carrier castingsBe sure all old gasket material is removed from mating surfaces and that carbon deposits have been removed from exhaust passages2Inspect casti ngs for cracks or fractures3Check sealing surfaces for nicks deep grooves and distortion which could cause leaks
NEEDLE BEARING
1C lean need le bearings in solvent and dry with compressed air2Repla ce bearing if needles are rustedfracturedworngalled badly, discolo redor if area of shaft that bearing contact is worn or pittedRefer toDrive Shaft" following
4Check water passages for obstructions