Here's a new one to me, and I've legitimately had or been around easily 2000+ disassembled engines. Not going to say what kind of car/suv/truck this is, but it was less than a week old. Owner said they heard a loud "ca-thunk" and then the engine wouldn't turn over...... I figure the valve had to have broken while the piston was at BDC and was just starting it's up stroke, flipped a damnnear perfect 180, and Mister Piston proceeded to impale himself with the stem like a nail on the first try. Funny thing was it was holding coolant on top of the piston and not leaking a single drop down. Wiped up the coolant to discover this, and not a mark on anything, but the valve ain't coming out of it's new home. It's that stuck....kinda cool.
I hope they are at least replacing the entire engine, if not the whole car. Personally, I'd hold out for a new car...
I had the exact same thing happen to a 455 I had in a CJ5 years ago. I over revved the engine in 4 wheel low and dropped a valve through the piston just like that. Engine made a clunking sound every time the piston came up to the head. Craziest thing ever I thought. I just replaced the piston and valve and the engine ran perfect till I pulled it out and had it rebuilt by JW for my Regal.
The valve in this engine had the stem snap in half. Everything looked just fine with the valve cover off.
I'm not joking. This engine is in our shop right now. Literally the only thing wrong with the piston is it has a valve stuck through it.
Pic of the head. You can see where the valve imprinted itself into the two exhaust valves and spark plug.
