Diamond Block Questions

[Model A Fan]

I have decided to exit the Model A hobby for the foreseeable future and will be parting with many of my extra pieces and whatnot. I have a diamond block engine that is numbered *A4870927* which brings the year of manufacture in right between 1938 and 1939.

What I'm hoping to find is more information about what their "deal" is. Given Model As were produced up until 1931, it is unusual for an engine to be produced so late. I understand that they may have been extra engines or that they were produced for non-auto uses. Does anyone have more information?

Also, what would be the value on one in good shape and in running condition? Mine has been painted a metallic blue, but is still operational. I don't think it would need a rebuild, but maybe just new gaskets. Thanks for the help.

I have included a link to the pics, they are the very last two photos on the album here:

https://www.jalopyjournal.com/forum/...or-sale.27941/