Wanted to share some engine related failures I have come across recently when building my own 4.3l V6 at my machine shop.
I help them sometimes and have been able to disassemble some customer engines.

Both cases are very interesting:
First is a big block with abrasive contaminants in the oil. Most probably a mix of casting sand eventually other material too and later on metallic particles. The engine was still running but used a lot of oil. Cylinder walls were not even so bad first oversize hone was enough to remove them. Made for a nice barcode thou!

The piston pin is interesting and we could determine the wear by "eye". The bearings have done their work and have embedded part of the particles but got a good scratching. Will be ground to the next smaller size and will get new bearings. Also not a total failure but an interesting example. Made some noise according to the owner, most probably because of the worn piston pins and would have failed in the future if not taken care of.


Second set of 3 pictures is a Chevy Corvette some 80's small block race engine.
Broke one valve after seizing a guide. Engine was still running as the owner completed the lap and came back to the box. (Account from the owner)
Loss of power and strange noises was what he said.

Found that one valve had broken and smashed up the face of the valve and broken it into several pieces. The largest one was about 1/4 of the total surface of the valve.
Now the interesting part is that this part was found diagonally from the failed cylinder wedged inside of the intake valve. This means it had traveled up into the intake and taken some detours through an additional 3 other cylinders before being lodged in the intake of one cylinder and wedged in.

Nearly everything is broken except for the crankshaft and a couple of cylinders. Not too sure about camshaft as parts in the valvetrain were broken as well.

 

If we're sharing engine failures, how about this mess I pulled out of the oil pan of my 91 Toyota 22RE with 296k original miles when I was rebuilding it (old timing chain guide that disintegrated that someone didn't clean out after a timing chain fix, who knows how long it was in there...), or the actually CRACKED rod bearing...

 

ah excellent! It always amazes me what punishment certain things can take and still work more or less.

Have to see - should have more engine failure pics. I sometimes can work on my stuff at a friends machine shop. And the guys are very specialized and get all the worst crap to fix.

 

Found a nice camshaft and solid lifters at my machine-shop.

Their customer was riding the engine with a modern oil instead of one with enough ZDDP additive.

Lasted some 300 miles before rebuild.

 

And another nice failure.

This comes from a L6 race engine. The guy completed the lap to get to the paddock. The result is that it cannot be figured out what let go. So they don't know if the valve let go or something else led to the valve finally break. The pistons were all still moving and still inside the bores. So a lot of luck there.

P.S. The second time actually they break this engine on a race.

 

A very nice one being brought in by one of the customers and acquaintance of mine to the machine shop I'm building my blazer engine:

2 liter inline 4 CVR engine, where a low quality piston pin let go.

Amazing that the piston came out in one piece...

... well, more or less, as it was held together only by the piston rings remainders.

 

When swapping a 318 from a Duster to a Dodge Dart a long time ago (20+ years), I decided also to install a new oil pump. The previous owner mentioned a lack of oil pressure. When I took off the pan, I found the remains of many of the valve stem covers, all brittle and in little bits. Being covered by the springs, I had not noticed that many of the covers had disintegrated. (I should have made a better inspection but I was much younger then!) To avoid taking the heads off I had to use the trick of supplying compressed air to each cylinder to hold the valve in place so I could release the spring retainers. I was paranoid that I'd drop a valve but it all went smoothly.

Motor ran strong for another 3-4 years before I sold the car.

I kind of miss that old Dart. Even with only a 2V-carb, it was quick! Had a larger rear-end in it too. When a friend's mom borrowed it who was known for being a bit of a "lead-foot" she exclaimed when she got back "That car goes like a son-of-a-bitch!" LOL

 

Found a new one. The owner wasn't convinced too much that he had a detonation problem. The machine shop was pretty sure of that.