engine gets really hot during driving

What is your question?

I have been driving my 2000 Ranger 4.0 for about an hour, engine starts having smoke from the hood. Checked oil, down .5 qt, put some in. Not overheating and temp gauge not rising. Checked under hood after a few minutes of stopping and could only smell a bad smell. Nothing showing on fire or burning or overheating. What are these rangers know for when it comes to engine heating up? Thanks for your time. What seems to make the problem better or worse? Not sure