Unknown engine failure

[maxidodies]

Engine went pop and stopped, opened it up and found this:






Was wondering if anyone had any ideas of what might of happened?
[--> Engine was put together with box full of parts, piston has been colored, sleeve was flawless though. Con-rod was also colored on one side, was not loose on crankshaft. Engine was ran at the time rich I believe.]

Thanks.

[X_Spurt]

Not really sure what caused it.

Check your crankcase though.

[Wolfslash16]

Werid. I've NEVER seen a rod break at the rod hole like that, it normally splits the rod down the middle, or just snaps. It kind of looks like a piece of the piston skirt broke of and took out the connecting rod... Not sure though, that really sucks.

[NathanM]

I had a rod split down the middle, it separated at the piston end. The engine continued to run with the broken rod and still had enough power to move my Revo 3.3.
I would agree the piston broke then destroyed the rod.

[Jersey Jato]

How many gallons were on that block & I bearings. It could be bad bearings in the block.

[TraxxasSummitCrawler]

Yup, like the other have said, the piece of the piston skirt broke of, go in between the bottom of the rod and when the rod came down, it smashed it into the side of the block! Now your making me afraid that my skirt is going to break off and do that! Mines cracked half way around the piston

[spudler_t]

Wow I havent seen anything this Knarly Since I lost a Rod/Main in an Truck I modified to run in Mud/Off Road/Tought Truck stuff.
had a Modified Webber carb Header and 33" Terra Tiers on it kinda like the T-Maxx Tires that are Like tractor Tires.
It completely tore a huge hole in the block and pan as it came apart at about 7,000 RPM at Full throttle.
I was not aware these Blew up like this although it should not be a surprise seeing I read these turn at 30,000 RPM or something Insane like that. I think that is faster then a Die Grider and maybe a dentist drill lol. no wonder they have such a cool sound when running.

[westoakmech]

It could have been run lean/hot, and made the piston brittle. Running too rich can be as bad or worse than running lean, because it puts alot of stress on the rod, wrist pin, and crank pin. Alot of times a failure in 1:1 engines in the wrist pin area of the rod and piston are caused from over reving. I have seen 3.3's running rich to the point they wont shift, and guys wind them out and split the rod. But there are alot of things that just happen. Hope you get back up and running soon. Good luck.

[Wildman4910]

Run too lean at some point in it's life.
Once the piston skirt gets cooked it's only a matter of time till it says "I've had enough!"

[maxidodies]

Thanks for the replies, this engine was put together with some old random parts. The piston was pretty baked before I assembled it, so I guess it was just a matter of time before it blew.