Is there anyway to safely mount a ceiling fan to this type of older ceiling junction box (see the photos)?
I rent an old 1920's built house where an old hanging light fixture junction box was covered with a blank panel. I want to hang a ceiling fan in this living room, but when exposed I see this old junction box that is really in the plaster and would be a huge hassle to replace.
One photo is how it looked when I first removed the blank cover. You will see the old threaded light fixture mount. With that mount removed as well as some plaster, you can see it is in there pretty well. There is no access from above it since that is a wooded bedroom floor directly upstairs. That junction box appears to be held sturdy by the two rusty-colored head screws (see photo) to a metal cross bar behind it.
I am sure my landlord would not be cool with having the ceiling torn apart more to replace this old junction box, so I wanted to see if anyone thinks there is an adapter or way to retrofit and adapt this box to mount a ceiling fan.