Mysterious Size of Woodruff Key for Steering Gear Ball Arm Part#3548 Question?

[Matt in California]

I am helping a friend with there Model T and discovered that the steering gear ball had the wrong key and there was play. Since that is the only part I need I figured I could go to the hardware store. So I looked up the size and was surprised that I came up with two dead ends.

#1 Steve Jelf's world famous reference just has "???" see: http://www.mtfca.com/discus/messages/82 ... 904367.pdf

#2 This thread on the MTFCA from last year left me with more questions than answers:
http://www.mtfca.com/discus/messages/82 ... 1525568272

Is the Woodruff Key for Steering Gear Ball Arm Part#3548 just a standard key or something else?

Thanks,
Matt

[DanTreace]

The Steering Gear Ball Arm Woodruff Key, p/n 3548, is 1/4" wide x 7/8" long x 11/32" tall.

[Ruxstel24]

I would say the proper torque on the pittman arm nut, locking the tapered fit together is as or more important than the fit of the woodruff key.
Just sayin...

[DanTreace]

Yep, that too, and the cotter pin on that castle nut

[rondupree]

The problem is that Ford used a big key in a small diameter shaft. If you try to use a standard woodruff key, it sticks up too high and you cannot tighten the pitman arm on the steering shaft. The 'special' Ford woodruff key has been ground to reduce its height by flattening the rounded side. This allows the pitman arm to seat properly on the shaft....Don't ask me how I know..

Ron Dupree

[DanTreace]

Thanks Ron

Your important tip is correct.

Should have posted the sketch.

Many 'hardware store' replacements for Ford parts don't always fit or function like the actual part.

[Matt in California]

Wow! You guys have all been very helpful! Awesome sketch Don!

I plan to go to the hardware store and buy a 1/4" x 7/8". Then I will then grind it to size.

Thanks so much!

Matt