Mike do you have children out by your work area. From a kids perspective, I can see that little ball bearing on the floor and picking it up looking somewhere to put. Ah ha Daddys engine. Drops it in. There all better. lmao. Its just a possibility with children.
Well you need to get that bearing back up in the steering stem. That is if it isn't square now.
Glad you found the problem.
Oh geez, just laughed and spewed beer on the monitor! Too funny...but sooo plausible!