I never have the right pictures at the right time... anywho, I noticed something moving in the background (some lever looking thing) before the engine kaplooied, and reading the comments I came upon this one: "If you look closely...the lever thing at the back is the governor...they shut it off and the engine immediately over revved and blew its conrods."
One of you auto doctors familiar with this type of engine that can maybe elaborate?
That was a most probably a diesel engine. In heavy machinerie or stationnary engine, where the engine drive hydraulic pump/generator(ect...) rather than be connected directly to the wheels for power like in a car via a transmission, it is desirable to have a stable engine speed(RPM). A governor is a contraption that allows one to set a desired engine speed and the governor will keep it there and compensate for the load raising/lowering depending on operating condition. Kinda like an engine speed cruise control.
I'm not a diesel guy for one bit so I can't identify that lever thingamajy that moved, but one could guess that there was a governor failure and it opened the throttle wide open. It's called a runaway engine. It got rotating so fast that internal parts could not keep up and something broke, triggering a chain reaction.
Since I work for a Toyota dealer, I'll use an example I'm fammiliar with. The 2ZZ-GE engine is a 1.8l inline 4 cylinder that was quite prone to this kind of failure. Not because of bad engine design per se but rather user mistake for the most part.
This engine was installed in the 2000-2004 Celica GTS and often coupled with a 6 speed manual transaxle. The way these transaxle are designed is the 6th gear is located right where the reverse would be on a 5 speed. Let's just say that someone not used to shifting that particular transaxle could mess things up. They'd get the engine at the redline in 5th gear and then, trying to engage 6th, put it in 4th and dump the clutch, instantly over-revving the engine. When an engine over speed, many things happen but in particular here is the fact that the exhaust valve springs could no longer close the valve fast enough and the piston head would slam the valve with force.
Best-case scenario, this is what happen.

If you got that, 8 exhaust valve and a pretty invoice later, you're back on the road
Worst case scenario well....

Something like that happen when the valve break and get "tumbled" in the cylinder. Notice how it pierced a hole in the piston and broke a piece of the cylinder wall and of the piston in the upper right.
Some more shots


That one is totalled. And a very nice(read "prohibitively expansive") invoice to boot too.
The sad part is those small car are most often owned by kids who have way more testosterone than money.
One guy told me once "a rich's head with a poor's body".

Y'know....the type of guy who roll in with his cheeky attitude and a 2 years old luxury sedan, then when you tell him he needs tires, ask you to put on the cheapest one you can find and pays with 4 credit cards? Gotta love my job....made me loose all the faith I had in humanity. But that's another story for another thread. Seeyall gents
