Firestone 7.5hp SN#13352317

[Big River]

I have this 7.5hp Firestone Engine, and need a few parts. Can anyone tell what year model this serial number is, and where can I find an impeller for it. I think that the Seirra Coil # 18-5181 is the right coil, but not sure. HELP Please.

[Tom @ Buzzard Bluff]

I have this 7.5hp Firestone Engine, and need a few parts. Can anyone tell what year model this serial number is, and where can I find an impeller for it. I think that the Seirra Coil # 18-5181 is the right coil, but not sure. HELP Please.

The best I can do is tell you that following WW2 Firestone contracted with Scott-Atwater to supply them with engines until the late 50s when the contract went to West Bend. Shortly after assuming the Firestone contract West Bend was sold to Chrysler who lived up to the end of the West Bend contract. Sometime @ 1963 that contract ended and Clinton provided some of their air-cooled motors branded as Firestone for the last couple of years that Firestone sold outboards.
So as you can readily see making a determination of exactly WHO was the actual manufacturer of the Firestones is challenging.
The Sierra coil P/N 18-5181 is intended to be used with the OMC 'universal magneto'. However they have been adapted to work on many other brands that use a 7/16" pole shoe lamination. If I get any shop time tomorrow I intend to use an 18-5181 coil winding to replace a bad one on a '76 Chrysler 6 horse twin which uses the Wico magneto system. It's either that or pay the $120 some are asking for Wico coils!
Flying Scott Impellers should be able to help you get your waterpump working and should be able to put you in touch with "The Scott Guy" who can help with identifying your motor and supplying parts IF it is a S-A product.
Good luck and keep digging! Tom

[F_R]

Your Firestone model 1335 is a 1953, made by Scott-Atwater.

[tmcalavy]

www.acmeoutboards.com has a service manual for Scott-Atwaters if you need one.