Birken Vogt
This is the common late 90s/early 2000s Mitsubishi unit.

Customer brought this rotor in to me. It has been flopping around on the shaft. The bearing feels fine. How could the shaft be undersized this much? The bore where the bearing presses is good.

The rotor has rubbed into the stator lightly but about 3/4 toward the engine.

Other than that everything looks fine. I need to see if this shaft can be sleeved or otherwise repaired.
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78buckshot
I would think the bearing spun on the shaft and "machined " it to the diameter that you have now.
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Birken Vogt
That is how it appears, however, nothing feels wrong with the bearing.

I am having the shaft welded up now and then will have it machined back to the correct dimension and put on a new bearing.

Normally the bearing will be destroyed before it gets to this point from what I have seen.
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78buckshot
It may have been a bad fit from the start and didn't run enough to damage the bearing itself.
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nrp3
These are cheaper to repair than replace or is it something that isn't available new anymore?
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Birken Vogt
Looks like they are available still, maybe a bit cheaper to repair than replace especially when you consider it is truck freight to ship the heavy old thing. As usual they want it NOW and so repairing looks to be the quicker option.
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