Not a vacuum leak/lean issue but more of a too retarded timing issue, I'm not certain how retarded timing causes that much heat. The spring should be the same diameter as the inside of the hose and yes, ends bent in to avoid punctures. IMO the lower hose on a closed/sealed coolant system shouldn't collapse unless you have a considerable restriction.
Common sense, the least common of all the senses. Mom.
For fear of ridicule, society stifles creativity. Ricky Valdes
