I think it depends, I’ve known of someone doing it in an old wreck years ago, and after refilling with the correct fuel it ran as well as it did before (which is to say it smoked and sounded like a bag of spanners). No idea how much it may have shortened what life it had left, but it wasn’t instant death.
If I’m not mistaken, it’ll kill old diesel engines, too.
I think it depends, I’ve known of someone doing it in an old wreck years ago, and after refilling with the correct fuel it ran as well as it did before (which is to say it smoked and sounded like a bag of spanners). No idea how much it may have shortened what life it had left, but it wasn’t instant death.