The first rubber impellers in Evinrude outboards appeared in the late 1940s. The 1948 alternate firing Sportwin was the first. The 1949 reversing Zephyr was the second, followed by the 1950 Fleetwin. The engineers learning curve from ’48 through ’52 was difficult and included many changes in design. The impeller hub and how it attached to the drive shaft as well as the impeller housing changed many times. Even when new you had to have the serial number in order to receive the correct part. Newer impellers may have the same dimensions, but the drive shaft may have to be turned down and drilled for a drive pin to make it fit early models. . . 🙄
1950
1952
1954
