I'm sure when I first glanced at this thread there was a paragraph re Door Hinge Pins , Its gone now could some kind sole add it back in please?
7. Sagging/Thumping/Uneven Door
Everybody loves this. You will be hard pressed to find a driver's ZJ door that doesn't have this problem. The door pins that hold the hinges on eventually go bad and will cause the door to sag and thud when it opens/closes. The super cool pin striping plus up and down door movement is the easiest way to notice the problem. Here is a great write-up on how to replace the pins.
"Third, flush the coolant system. There is a plug at the bottom of the radiator that makes this an easy process. Please don't do this while engine is warm."
Back when I was a teenager, I watched my step-brother do basically that exact thing. We were driving and he notice the engine seemed to be getting a little too warm. We pulled over, he popped the hood, reached for the radiator cap and burned his hand. SO HE GETS A TOWEL AND OPENS THE CAP!!! Luckily he jumped back and somehow didn't burn himself bad. I'm a ***hole, so of coarse, I laughed my butt off.
There's never time to do it right, but there's always time to do it over.