This is commonly one of the most common questions when it comes to Flathead V8’s. How does one tell if you have a Mercury crank? So, this photo, supplied by H&H Flatheads is one of the best examples of how to tell the difference. The crank on the Right is a Ford Crank. The Crank on the left is the Mercury. The oil ports on a Mercury crank are much larger. In fact, big enough to almost stick your pinky into.

The oil ports on a Ford crank are quite small and about the same size as a pencil. Without really getting into the stroke length this is the easiest way to see what crank you have. So, the next time someone is trying to sell you a Mercury engine, make sure you have them drop the pan and take a photo of the crank so you can confirm. This is one of the largest way people get scammed on buying a new engine.

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