R

RyanM

Well Known Member
This is picture from a Archer II. A co-worker was flying was the 2nd to last person to fly this plane. The pilot & passenger were not hurt during the forced landing.

What would cause this type of failure in an engine?

According to my co-worker, the Haverikommisionen (the Danish NTSB), said they have never seen an engine ?break up? like that and they requested the engine for further examination.

engineit0.jpg
 
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It looks like either a connecting rod broke or perhaps the crankshaft let go. I've seen similar damage in some auto engines after a rod failure due to over revving or oil starvation.
 
Hard to say without taking the engine apart, but it looks like the rod is badly bent. Possibly caused by overspeeding the engine, a broken crankshaft, or even from a broken/dropped exhaust valve that might be lodged in the top of the piston???
 
Dang mogas. A little JB Weld and it will be good as new.

The preceeding was a politically incorrect joke.
 
A few reasons

If at overhaul the rod bolts were not replaced or overtorqued. I had an IO-520 Conti years ago that cracked an oil cooler which was replaced. The gasket was bad so the mechanic used some RTV as a gasket. Bear in mind that this oil cooler bolted directly to the engine's oil cooler adapter plate.

The next day, the engine threw a rod right through the case. A piece of RTV was lodged in the crank oil passage and starved that rod.....Kaboom!

Chit happens,
 
If you magnify the picture a little, you can see some details better that support probable rod failure. The flange on the bottom of the jug is bent outward with the surrounding cast material being fractured (pealed) laterally as well. That can only be from something inside trying to get out.
My guess would be that the rod let go and was thrown into the case resulting in your vent hole.

Jim Kinsey
7A Fuselage slowly
getting there
 
"Looks like we threw a rod."

"Is that bad?"

"Yup."

-Seriously, very glad everyone was OK.
 
K?hler said:
"Looks like we threw a rod."

"Is that bad?"

"Yup."

-Seriously, very glad everyone was OK.
Click to expand...

Seriously. You can't post the quote without a link.

The quote is at about 5:30 in the 8 minute clip
 
Well That is your problem right there

The Mechanic Expert says to the Pilot: That's your problem right here, you got a big hole in engine, yep, that's not suppose to be like that, nope not at all. :rolleyes:

Did that with a a small block Chevy, the rod came right out the oil pan. When things like rods, rod caps, rod bolts, cranks fail it will likely get ugly.
 
Too many cycles on rod, bolts, crank etc. Improper big end sizing. Lack of oil, seized wrist pin/ piston, rod bearing problem, metallugical flaw, dropped valve. The list goes on. Aircraft engines are not immune to these types of failures and I'm surprised that that your guys have never seen this sort of thing over there. I can think of at least 4 I've read about in the last 2 years and seen one myself at my airport a few years back in a Comanche.

Food for thought if you have tall trees at the end of your runway or spend a lot of time looking at rocks down below... :(
 
I bought a "parts engine" that looked exactly like that. 300 hours smoh, owner ran it out of oil and threw a rod. I opened the case and it looked like it had ran for a minute or two more before they shut it down.
 
Wow

When I saw the hole, I thought of our Canadian Giant Wood Peckers might have been responsible...but... ;)

Quite a hole in the Crankcase. Our club 172 Lycosaurus did the samething last year. Quite a scare when it happens to you, thats why we practice forced landings...... :cool:
 
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