Jim,
I’m not sure if my 1952 Firestone 10hp has the correct drive pin as it extends enough to contact both sides of the impeller installed. This requires a square channel[ 180 degrees apart channels for both pin ends to make contact but gives a 100% better drive for the impeller. I also see a round ridge on the impeller blades for sealing the top & bottom sides like a Mercury impeller blades as well. Contact data is as followes. The early impellers had a a nylon center hub too. It will well for a very short life. A brass impeller hub must be used on all of Bob’s service work too. Please let Bob know if you have a many paddle impeller or a Hockey puck type or is for the the bailer housing . I too have used Bob’s impellers that have worked very well too in my 3.6, 7.5, 5 & a 54 10hp Firestone cooling. Once again his address, I don’t have his phone number at the shop. If you need anything else email at Jeff.50@cox.net.
Bob Long
325 Washington street north/east
Building 433
Olympia, Washington 98501
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