Mercury / Marine : 40 HP (4 cyl) Serial # C159200-G589999 45-50 HP (4 cyl) Serial # 5531630 and higher 75 HP (4 cyl) Serial # 6432901 and higher 80 HP (4 cyl) Serial # 4831999-6432900 80 Jet Serial # D283222-6437999 85 HP (4 cyl) Serial # 4366802-4831998 100 HP (4 cyl) Serial # B209468-6437999 115 HP (4 cyl) Serial # C100000-G437999 125 HP (4 cyl) Serial # D283222-G437999