I am not sure there is much that can go bad in them with age? I had one on my car for a few years, then the car sat in my garage for 6 or 7 years. After the hibernation I filled it with gas and fired it up and the pump was fine, I even did a Drag Week or two on that pump before I went EFI. Its now probably 20 years old and sits on a shelf in the garage. I try to drop a few drops of oil in it and connect a battery to spin it over when I think about it.