Deisel engines, as long as they are properly maintained, are fantastically reliable machines—in over 40 years I have never had one fail in such a way that I was not able to get it running well enough to get me home.
But overheat a diesel engine badly and all bets are off, to the point that not only might the engine not get us home, it might never be reliable again.
I know of at least three incidents where owners overheated a diesel, spent a bunch of money trying to fix it, and then finally had to re-power—a huge suck.
And each of those cases was avoidable. Let's look at ten ways to do that.