u/Interesting-Most-110

So I recently got an air compressor from someone I know and it was used somewhat regularly (at least weekly for the most part) and as the title states, I’m curious if I should simply open the valve on the bottom and drain it. It hasn’t been drained in a few months and I’m well aware of old air compressors being filled with water and eventually blowing up, killing the owner. But I’ve heard that happens after eventual failure due to not draining it, but is it safe to drain while turned off, if it hasn’t been in a few months? Or is this a bomb that I shouldn’t go anywhere near?