Chrysler 20 and 30 HP Outboard Motors Service Manual OB 3435, Page 145Get this manual
GLASS OR SURFACE PLATE
FEELER GAUGE
Figure 35Removing Crankshaft Spline Seal
Figure 36Checking Flatness of Cylinder Head
4I nspect crankshaft bearings and seals as follows :
ACheck upper and lower bearings for rust, cracks
or wearBPress on new lower bearing if required CCheck upper and lower crankshaft seals for nickstearsor wearDlf neededremove upper crankshaft sealFigure 34and crankshaft spline sealFigure 35EInstall new spline seal