What is the big U-bolt for on the front end of Farmall A?

Hi Folks,
Finally putting my Super A back together after taking the front axle off and fixing the steering. I was wondering what the big u-bolt is for that goes around the front axle. Mine was intact but only had a nut on the front threads, and no nut on the back threads. The back half extends through the bolster but did not have a nut on it. Actually there was a nut in back below the bolster but not above so the back arm can just slide out once the front nut is removed.

What was the purpose of this u-bolt? Should it have a nut on the back threads?

Thanks for your responses.

Put a nut on it. It is used to limit axel travel

The axle angle down to the right is limited by the front casting on the engine, the tilt down to the left is limited by the U-bolt otherwise the axle could tilt to quite a large!! angle

(quoted from post at 14:21:13 03/27/17) The axle angle down to the right is limited by the front casting on the engine, the tilt down to the left is limited by the U-bolt otherwise the axle could tilt to quite a large!! angle

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Thanks both of you for the responses. I'm guessing that this range-limiting feature is mainly for when you jack up the tractor. It's hard to imagine a scenario where the axle would tilt that far in the field.

Were you able to get the steering tight? I have had mine apart at least three times and I still have at least a 1/4 turn play in the steering wheel and the tie rods allow the front wheels to wobble when going over clods. Drives me crazy.

(quoted from post at 06:03:23 03/28/17) Were you able to get the steering tight? I have had mine apart at least three times and I still have at least a 1/4 turn play in the steering wheel and the tie rods allow the front wheels to wobble when going over clods. Drives me crazy.

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Doug, weld the worm gear to the shaft and then make sure your bushings and tie rods & balls are good and tight. I can supply you with new weld-on balls and can weld your gear if you need me to.

(quoted from post at 18:03:23 03/27/17) Were you able to get the steering tight? I have had mine apart at least three times and I still have at least a 1/4 turn play in the steering wheel and the tie rods allow the front wheels to wobble when going over clods. Drives me crazy.

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Hi Doug. I lucked out. I had the same problem as you, a quarter turn of slack and difficulty making straight rows.

My problem was where the external steering arm fits to the vertical shaft below the steering gear box. All I had to do was invert the woodruff key and tighten it back down. It was easy to detect because once I unhooked the tie rods, I could move the steering arm back and forth by hand without moving the vertical shaft.

Here is a reply from JaNicholson that was useful to me:
The slop in the steering comes from two main places. The gear box has two shafts one hooked to the steering wheel, the
other hooks to an arm on the bottom of the box. If the shaft to arm keyway has been loose, the shaft can be seen to move without moving the arm. Removing the arm will show the problem. If it is bad, the fix is to use a dremel tool to recut the Key pocket to the next larger size/thickness, and have the arm broached to match the bigger key. (new key pockets can also be machined into the shaft, but the whole shaft would need to be removed) If ti is a square tapered shaft, (I can't remember which it has) replacing the shaft may be needed.
The other place for slack is in the ball bearing at the end of the steering shaft (behind the big nut) If it is toast, replace it.
Other issues can be spindle vertical bushings, and tierod ends. Easier to see and fix. Jim