Connecting Rod Carnage

March 27, 2003

I hate being right. ;^)
I dropped the Patrol oilpan today and found this:


You can see the con rod, piston pin and I guess pieces of the piston. I'm not sure what that gasket-looking thing by the piston end of the rod is. Those round dents on the left side of the pan are each from the bolt end on the rod hitting it. One hole actually is threaded and punched all the way through. The last one from when it actually came down is lower and a big dent and hole near the bottom of the pan. Looking at them, I can still hear the "Duh-duh-duh-duh-duh-BANG!" as I was trying to get to the side of the road. One of the bolts is bent up and the other is fine. The rod cap is perfectly intact.
You can see what's left of the lower part of the piston in the top pic. There were shards littering the pan and a neat little pea-sized chunk of metal with the Nissan logo on it.

Here's the crankshaft:




After looking at the debris - it looks like one bolt came loose on the rod end cap. One was bent and busted with the nut still on it and the other was intact, along with the nut, laying in the pan. The cap is fine. I'm guessing the nut and bolt came loose, the rod slapped a few times until it caught and tore the pin out of the piston and went flying. Something like that.

My theory is that someone replaced the main seal and had to remove the #6 rod cap to do it. When they reinstalled the bolts and nuts on the cap they forgot to torque down one nut and it came loose while I was driving it.