[Mike Pearson]

plug both ends and put about 15 lbs pressure in the line with your air compressor. let it sit for a few days and see if it holds pressure. bend the line while the pressure is in the line if the rubber is rotten of weak it will start to leak. if the line has never been used and is pliable it might be OK. Like several others have said it might not be worth the aggravation. From my experience the older line seemed to be better quality than some of the new stuff.