Mercury Mariner 4, 5 102CC Sail 1990 Outboard Service Shop Manual, Page 57Get this manual
Powerhead Disassembly Cylinder Block
1Remove bolts (a) from seal housing (b)
4Remove oil seal housing (a) and gaskel (b)
5Remove5 bolls (a)cy linder head (b) and gasket (e) dl 2Use soft face hammer to loosen 11 SQ housing (a)