In addition to the serial number, the horsepower of the engine in question must be known to determine the year model of a Mercury outboard.
In order to answer this question, the horsepower rating of the motor has to be known. Mercury outboards use the serial number, and horsepower, to determine year model.
There are two items needed to determine the age of a Mercury outboard, the serial number, and the horsepower rating.
1950.
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