Robert there should be an ID plate on there with a model number. If that is indeed the case….go here and you can find the year:
http://discount-marine-parts.com/ob_firestone_1.html
http://discount-marine-parts.com/ob_firestone_2.html
http://discount-marine-parts.com/ob_firestone_3.html
Otherwise; post a picture here?
Depending on the vintage; Firestone motors were made by Scott/McCulloch, West Bend and Clinton.
