Ok, I am hoping someone can help me with this.
We have several Otis Gearless machines with hollow shafts. I am inquiring whether:
1. Can you repair or replace or alter these hollow shafts in place. If so what how and what is done. Is there any technical literature as to how to do this?
2. I know it is probably easier to replace such machines, but access in and out of the machine rooms would make this rather expensive and difficult.

So that is why I am inquiring about #1 above.

Your help is greatly appreciated in advance