The year model of an Evinrude outboard cannot be determined from the serial number, but rather from the model number.
The year model of an Evinrude outboard engine is determined from the engine "model number", rather than the serial number.
The 5602R is a 1966 Evinrude
With that serial number it would be a 1986.
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.
Its a 1970 Evinrude Mate. 1.5 HP.
1955 3hp
Its a 1971
1972
5.5 HP 1964 Evinrude Fisherman 5402B-E02180
1961 18 horsePower
1981