I was always taught that when purchasing a diesel you want to make sure that it does in fact shutdown abruptly, as it is an indication of the tightness of the internal engine components. Has the diesel rattled om when shutdown then it is indicative of a sloppy timing chain and additional worn internal components, with the exception of the older diesels that may have a faulty vacuum shutdown or leak. Those I would just use the manual shutdown and see how long it took the engine to react......The weep hole on your water pump leaked and it is the most common tell-tale sign of water pump failure.... It's a pain but every weekend I pop the hood, check all my fluids then crank it up just to check the belt alignment and the accessories that it drives!

To close this, I put on a new water pump, tstat , tensioner and belt. I previously had an 82C tstat in before and now have a 92C one, so it runs warmer. It now gets toasty inside.I confirmed with my scangauge at 195-197 degrees. It took a little longer than expected, that underbelly shield is a real pain to deal with.