Originally Posted by
Simplex
I guess that involves taking the whole BB's apart, replacing bearings cleaning and regreasing, is it possible that the spindle is worn on the inside and would also need replacement?
Yes, it's possible either the spindle or the cups will be worn out and need to be replaced. After you clean them, look for any pitting or other damage/deformation of the surfaces that the bearings roll on. If they're both smooth, you're good to go. Regrease and reassemble. Same goes for the bearings. If they're still round and smooth, you don't need to replace them, though if you're not sure, replacing them is relatively cheap.
If you do need to replace, the co-op likely has use replacements that might be okay to use. Just double check that they don't have any damage either.