1988-1992 Mercury Force 5HP Outboards Service Manual, Page 192Get this manual
3 Install O-ring (A)Slide pump body down shift rod and position on housingInstall water line seal (A)Install stud (8) Apply sealant (Special Tool NoT-8983) to threads of studMake sure the nut is up where the threads endScrew stud in as tight as possible by handDO NOT TIGHTEN NUT