I have a 25 year old shallow well jet pump and an even older pressure tank(both Kenmore or Craftsman)that probably came with the pump that I replaced 25 years ago. I recntly broke a part while draining and winterizing system. The part I broke is plastic---It connects to the pressure tank and is shaped like a cylinder with a spherical bottom. There is a floating ball inside. The top of this thing screws into a small pipe (3/8 inch maybe) coming out of the end of the pressure tank. The bottom of this thing has a connection to a small waterline (1/8 inch maybe) which in turn connects to the pump body between the intake and the impeller housing. I don't seem to be having any luck finding parts online that look like this thing. What's it called, what's it's pupose, and what can I do to replace it or bypass it? Are there newer replacement parts that don't look like this anymore? Or, do I need to look for an OLD plumber or pumpshop to look through their OLD parts bins. Thanks.