Mercury Mariner 25HP 4-Stroke Outboard Service Manual 1997, Page 40Get this manual
Installing OutboardNon Thumb Screw Models 1Mach (tape) engine mounti ng template (located in installation manual PIN 90-10184980) to boat transom
4Fasten outboard with provided mounting hardware shown,
,b Flat Washers (4)
2Mark and drill four 1732 in(13.5mm) mounting holes
a112 inDiameter Bolls (4)Locknuts (4)