Good Morning, is this Ford crankshaft marking denote an "EE" crank?
That's a 09-24 diamond throw style crank, they were never made out of "EE" steel like the later sturdier 1924-27 straight throw style cranks (You may find EE cranks in 1926/27 engines.)
Here's from the 1909 catalog when Henry Ford was proud of the then new vanadium steel - good at being bent, (but not as good against repeated minor bending and twisting as the later EE carbon steel)
Actually that style of crankshaft with Ford script was made from about 1914 to 1924 in the Highland Park Plant by Ford.
Previously crankshafts were made by Dodge Brothers for Ford. Dodge Brothers gave notice that they were going to stop supplying Ford by early 1914, and from all we know they kept their promise. The Dodge Brothers crankshaft are easily recognized by the "DB" cartouche and for their tendency to break in half unexpectedly.
Bob, This is what the typical EE crank in the '27 engine I have looks like. If you look closely at the side of the throw, you see a recessed area. The "EE" is cast into the crank there. I've also read about some EE cranks that were stamped on the ends, but I wonder about the originality of some of those.
There was also a straight sided Vanadium crank made and installed in some '25 engines that looks identical to the EE variety without the markings. Does not have the strength of the later EE cranks though.
Has anyone had an EE Crankshaft break on them?
Nevin, unfortunately all Model T cranks seems to be determined to break eventually if the car is driven, some just take more time - and EE cranks seems to be among those who delays the inevitable the longest.
Here's a thread where Jack Putnam describe how his EE crank broke when dropped (!) - but it's not like they're brittle as glass, it was already cracked almost all the way through since before from metal fatigue.
Here is a look at a typical Dodge Brothers crankshaft:
it has always been of interest to me fact that early Dodge Brothers crankshafts in Ford engines were know for breakage ...I currently own and have owned 8 Dodge Brothers cars and trucks in the past ...all but 1 being the DB 4 cyl. engine ( 1 Victory 6) ...I have never known of a Dodge Brothers crankshaft in a Dodge Brothers car/truck to break ...they are much larger diameter and the Dodge Brothers always had a conventional transmission and oil pan and large bell housing flange that was doweled to the transmission bell housing for alignment...I doubt that there was much , if any difference in the materials or manufacturing process used ...that leaves alignment as likely suspect ...always curious and always an optimist ...gene french
The engine this one came from was dead straight, had great Babbitt, and the pan was also straight.
I think the problem with DB cranks was that Ford specified using brittle forged vanadium steel and the journals are just plain small, combined with decades of use. Any of the Dodge Brothers engines are much sturdier than a Model T Ford, as they were a more expensive and higher quality car.
It's the large diameter that saves cranks in early Dodge Brothers cars that were made from the same material that breaks in Fords. Increasing the cranks dimension increases strength by the square, so just a little larger diameter makes a big difference in sturdiness and sustainability against metal fatigue.
With a large enough diameter, you can have a simple cast iron crank in a strong V8 that holds up just fine.
Ford didn't know much about metal fatigue when the T engine was designed in 1907 - and even though he and his engineers learned a lot over the next 20 years, stubbornness and the wish for backwards compatibility hindered any true resolving of the Ford crankshaft problem until the Model A.