serial number help

[casey_hill_1984]

hello i have a mercury 20 hp it says thunderbolt ignition on the fron has the aluminum band style clamp around cowl in blue letterin the serial number is 5731223 yet icant find it anywhere...i believe its an 80/81

 

[79Merc80]

Re: serial number help

That serial # comes up as an 1980/1981. Those two years are kind of lumped together.

 

[casey_hill_1984]

Re: serial number help

i saw that the numers are xxxxxxx-xxxxxxx im assuming the - means through but this serial number comes up nowhere i look