Before 1980, you use the first four numbers of the Evinrude boat motor serial number to determine the year it was made. Motor serial numbers beginning with 5402 were made in 1964.
7o
1977
1070310
1986
Unfortunately to find out the year of a Mercury boat motor one needs not only the serial number, but also the horse power rating. This allows it to be narrowed down to a specific year.
1986
1988
1981
its a 1956
Two items are required to determine the year model of a Mercury outboard, the serial number and the horsepower rating.
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