Hi everyone. I have a new COLD CASE radiator and I recently checked the antifreeze in it for the Winter. It only was safe to 0 degrees. My plan was to drain some out and put the exact same full strength antifreeze back in. I went to drain some out with the bottom drain plug and none would come out no matter what. Fully in or fully out, nothing. I then had to undo the bottom radiator hose with a tower clamp, and what a PITA that was. Antifreeze all over as usual. I then put full strength in it and I'm protected to -30 degrees below. Gets any colder then that, I'm moving to CA lol. Anyhow, I want to correct this problem. Should I try opening this drain with a wire or take it out completely and replace it? The whole radiator would drain if I have to take it out completely. Another mess. But, I do want it corrected. Must be plugged some how? I'm hoping to be able to buy a replacement if I need it. Thanks for any advice, Carmine.