Description Upper Main Bearing: Mercury / Mariner 45 - 60 Hp 3 Cyl 91-97 OEM#: 31-812873A1 Mariner ALL Mercury 3 Cyl 2.955 Bore Looper 50 1991-1997 Mercury 3 Cyl 2.955 Bore Looper 60 1991-1997 Mercury 3 Cyl 2.992 Bore 55 1991-1997 Mercury 3 Cyl Jet 45 1991-1997