Repairing LGB Ball Bearing Wheelset?

[Beacon Joe]

I need to repair an LGB 67403 Ball Bearing Wheelset with power pickups. One of the wheels has detached from the ball bearing and the plastic cap . How were these three elements originally held together from the factory? Were they just friction fit together, or were they glued or otherwise?

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[stevedenver]

Not defective.
Plastic may shrink, glue lets loose.
Ive had that happen a few times.
I use a couple of drops of super glue, obviously not where anything spins….done and dusted.