Take it to a rad shop, boil it out and pressure test it... only about $40 bucks or so to clean it.
Once it's shiny again, look for more corrosion, pitting and cracks. If it's pink, get rid of it, all the copper is gone and it's brittle, then replace. If it holds pressure, then its up to you whether or not to exchange it.
Me... I like new parts, but I'm crazy that way.
Once it's shiny again, look for more corrosion, pitting and cracks. If it's pink, get rid of it, all the copper is gone and it's brittle, then replace. If it holds pressure, then its up to you whether or not to exchange it.
Me... I like new parts, but I'm crazy that way.

All that obstruction was ROCK HARD. I had to use a small screw driver and a plastic hammer to chisel it out. If you intend to do this be careful not to rupture the copper tubing.