Tohatsu 4 Stroke MFS 2/2.5/3.5A Outboards Service Manual, Page 83Get this manual
Power Unit 5) Inspection of Crank Case Head
1Check crank case head for crack, damage and corrosionReplace if necessary
6) Assembly of Crank Case Head
1Attach new oil seal to crank case head by using commercially available mandrelApply lithium grease to the lip of oil seal