Interesting carnage. Rod bolt nut came loose?

[Stinky]

I recently pulled a vh45 motor out of the junkyard to use for mocking things up. The crank wouldnt turn at all so I started disassembling the motor to see what had happened. From what I can gather it seems a rod bolt nut had come loose causing some major damage. This is the first ive ever heard of a rod nut coming off but I cant think of any other reason for the carnage.

Here's what I saw when I got the bottom apart.

The bent rod and the rod bolt that got hammered into the block.

The nut got wedged between the counterweight and the block.

The rod cap holding on by the remaining bolt.

Impact marks on the bottom girdle where the rod cap was likely starting to come loose. My buddy counted about 18 marks.

The rod bolt and nut. Neither show any sign of being stripped leading me to believe the nut must have simply come loose.

The hole left if the block where the rod bolt hammered into it. It looks like it might have made it into whatever oil or water passage is next to it.

Comments?

[Florida240sx]

No striped threads... must of just came loose... found another vh45de? Sent my deposit

[David Steele]

Installer error.

[Florida240sx]

I beleive this is one that they had removed from like 120k q45.....

[Chuby]

I believe that was the same thing that happened to my recently destroyed VH. I have a complete rod bolt and a nut that looks to have lost its last few threads leading me to the conclusion that it started to come loose and then stripped the last few threads.