Marilyn's new Cub has a casting number (inverted) on the manifold. I haven't ever noticed a number on a manifold before. The number is very nearly a year newer than the engine the manifold is mounted on. 4-14-R (April 14,1948)
The number on the engine indicates it is an early '47. (April 19, 1947)
Were the casting numbers only on replacements? Does anyone have such a (any) number on their Cub's manifold? If so, does the code closely match those on other castings?