Posting this as an example when faced with an engine that runs fine, until it warms up.....then stalls, difficult to start or no start until it cools down. The wire pictured below was encased in wire wrap, basically black electrical tape, all the way up to 1" before the end. I removed the harness wrap on the entire engine harness looking for an electrical defect, and found this wire burned. The wire itself was still attached, but apparently when it got hot enough, the electrical current went elsewhere. This is the purple wire carrying voltage to the coil, which comes off the purple alternator wire. Back side of coil had evidence of overheating, possible oil leaking out the top of it. Replaced coil and this wire, problem solved. Hours involved searching for the culprit.
