In the process of going through Dad's old shop I have found literally found tons of old car parts. Some of it I have been able to identify, however some of it I'm not real sure about. This crank is one I'm not sure about. I know he had planned on building a hot flathead at one point in time and was collecting parts for it. I also know that some of those parts went on other engines over the last several years. There is a block that he had cleaned and checked and had a little machine work done to and it is sitting in one of the back rooms caked in grease. There is an oldschool reground cam sitting on the bench. There are also a couple aluminum intakes and a bunch of carbs and various other performance parts sitting here and there around the shop. This crank looks a little different to me and I was wondering if anyone here could help me identify it. There are three flatheads in the shop, all disassembled, but I've found four cranks. I think this may be a stroked Merc crank. How can I tell for sure?
Easiest way to know the stroke is set it on a couple wood blocks at the mains, then rotate and measure the difference from the table top. You have a late crank there, but hard to tell what the stroke is with your eye. I do see a bit of offset at those throws, but maybe that was just the casting not centered perfectly. Measure across the big counterweight. It should be 6" across to be a Merc 4" crank. If it is you know you have at least 4" of throw.
The Jalopy Journal
