Pin and Bolt. Upper Control Arm Pivot.

[Leo B]

Do I have the correct Upper Control Arm Pivot Pin #524227 or is it meant to be like this?
I have correct size bolt 3/8 and the hole for that is not exceptionally loose. The Pin locks easy when the bolt is tightened. But...
The pin groove allows for a lot of lateral movement and the groove is wider and deeper than intended for a 3/8 bolt. I can fit about a 0.6 inch bolt in the groove. The 3/8 bolt couldn't have made that groove. This greatly affects, among other things, caster adjustment.

Edited Friday at 05:22 PM by Leo B
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[mfg]

If the bolt is cinched up tight, there will be no movement between upper pin and the king plan.

[Zedman]

I checked my old parts stash (kept for reference !) and it appears to be the same as yours- I never checked this fit so I was also surprised.  Because the actual bearing surfaces are the screws and they rotate, the Pinch bolt Clamps the 'Trunnion' tightly and prevents its rotation. Don't lose sleep over this one ! 😴

[Leo B]

OK. So when I adjust the caster angle to positive, the bolt is against the left edge of the groove, thus creating maximum adjustment.
It's strange that the fit isn't more precise when the groove is suitable for almost a 9/16 inch bolt, but it's good that the parts are correct. Thanks mfg and Zedman.

[ronmanfredi]

14 hours ago, Leo B said:

OK. So when I adjust the caster angle to positive, the bolt is against the left edge of the groove, thus creating maximum adjustment.
It's strange that the fit isn't more precise when the groove is suitable for almost a 9/16 inch bolt, but it's good that the parts are correct. Thanks mfg and Zedman.

The amount of change you are mentioning won't affect the caster enough to make a difference.  Remember the king pin front end design of the early 50s wasn't set up for much caster.  Shinny bias ply tires, lower speed limits and mostly non power steering cars ran zero to negative caster.