Guess as to Origin of Metal Found in Oil Screen

iflyvfr

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Display name:
Greg
My mechanic showed me this last weekend when I stopped by to say hello. C-172 with an O300 motor; non-ferrous part found in the oil screen, spin on filter was clean. I'd say just over an inch wide. Appears failure was at the oil flow holes - at least that's what they appear to be to my untrained eye. Not my engine, just curious what this might be since i have same motor at TBO. I'd consider this pretty serious were this found in my oil screen.

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At any rate, it's parked in the back of the hangar, where birds that aren't flying anytime soon go.
 
Prediction - it is in the expensive part of the engine.
 
O-300D engine I'll bet. Looks like part of the worm gear wheel for the starter drive.
 
All I see is $$$$. Since you have the piece, a good place to start is the Illustrated parts Catalog (IPC) and look at the internal engine bits to compare the piece.

So sorry for your loss.
 
That looks like a $20K part to me ...
 
O-300D engine I'll bet. Looks like part of the worm gear wheel for the starter drive.
To get in the screen it needs to get from the sump to the screen,, accessory case wouldn't pass that large of a piece.
 
My mechanic showed me this last weekend when I stopped by to say hello. C-172 with an O300 motor; non-ferrous part found in the oil screen, spin on filter was clean. I'd say just over an inch wide. Appears failure was at the oil flow holes - at least that's what they appear to be to my untrained eye. Not my engine, just curious what this might be since i have same motor at TBO. I'd consider this pretty serious were this found in my oil screen.

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At any rate, it's parked in the back of the hangar, where birds that aren't flying anytime soon go.
Flush it out, run the engine it won't be long before you know. :(
 
Thinking about Tom's comment about the gold color being varnish.

0-300 piston

s828369910421562331_p26_i4_w150.jpeg


Looks like a piece off the piston oil ring groove above the piston pin boss.
 
If it's piston or ring, I'd think a borescope of the cyls would tell the tale.
 
If it's piston or ring, I'd think a borescope of the cyls would tell the tale.
I recall an industrial engine for an air compressor that I repaired. Missing badly, quick check found absolutely no compression in one cylinder. OK, that should be easy. Pull the head. Valves and gear look good. Piston looks good. Turn the crank, three pistons go up and down, one is stationary. OK, no sweat, broken rod. Drop the oil pan, no broken rod, no chunks of metal. WTF? Turn the crank, looks good. Things go roundy roundy and upsie downie. This does not seem not possible. All I can do is keep digging. Unbolt the rod ends, drop the crank out of the way, grab the rod for the bad cylinder, pull it out and I get the rod and all of the piston below one of the ring grooves. The piston crown is still in the block.
 
0-300 piston

s828369910421562331_p26_i4_w150.jpeg

Doesn't look like a normal O-300 piston to me. Mine have three compression rings and one oil control ring which is located near the bottom of the skirt. Pictures in OH manual look similar.
 
Measure the outside curve and calculate a diameter and see if it matches the bore size of that engine.
 
A piece that big didn't come from inside the engine. It would never make it through the suction screen or oil pump. It looks more like some part of the mounting for a spin-on filter.
 
A piece that big didn't come from inside the engine. It would never make it through the suction screen or oil pump. It looks more like some part of the mounting for a spin-on filter.

I understood the OP to mean it was in the suction screen, thus before the oil pump. Maybe I’m assuming facts not in evidence.
 
For future reference, adding a coin or dollar bill for scale in the pictures would be helpful.
Preferably a $20,000 bill

When I do oil changes I drop my filter off with my IA and ask him to "check it for precious metals. One of us might be rich"
 
I understood the OP to mean it was in the suction screen, thus before the oil pump. Maybe I’m assuming facts not in evidence.
If it was found in the suction screen, then yes, it might be a chunk off the bottom of a piston. A picture showing it turned over would be nice; it would show whether or not it had a ring land with the ring's marks on it
 
For future reference, adding a coin or dollar bill for scale in the pictures would be helpful.
Yeah sorry about that, I tried to take pics from all different angles too and something for reference would have been ideal.
 
I understood the OP to mean it was in the suction screen, thus before the oil pump. Maybe I’m assuming facts not in evidence.
Yes, that's what I was told when I asked, it came from the finger screen. I was told the oil filter checked out OK. Oh, and I said it was from an O-300D but in fact I'm not sure which version of the O-300 that motor is.
 
IIRC the O-200 and O-300 used the same pistons, and they looked like this:

s-l400.jpg
 
Just so happens I have a complete Superior assembly waiting to go, here's the NIB piston:
 

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This is POA. Did we get a reply yet where someone fixes that on his workbench for $1200 in parts and rants about the ripoff that is the engine repair business ?
 
This is POA. Did we get a reply yet where someone fixes that on his workbench for $1200 in parts and rants about the ripoff that is the engine repair business ?

Man please ... we had a fella at out airport that would have just tack welded it back in place, smoothed it out with a side grinder and run the engine hard until the noise went away from all the parts rubbing together. Seriously, he had an experimental airplane that he experimented with a lot but was always asking other people to fly it. That fella is no longer with us and actually passed from old age.

But we have a replacement now. Guy asked if I wanted to fly his plane and I said no. He asked why. I said, "cause I've seen you work on it."
 
Man please ... we had a fella at out airport that would have just tack welded it back in place, smoothed it out with a side grinder and run the engine hard until the noise went away from all the parts rubbing together. Seriously, he had an experimental airplane that he experimented with a lot but was always asking other people to fly it. That fella is no longer with us and actually passed from old age.

But we have a replacement now. Guy asked if I wanted to fly his plane and I said no. He asked why. I said, "cause I've seen you work on it."

I ended up doing an acro flight in a Stearman like that once. I didn't find out until after we landed who the previous owner/restorer was. Yikes.
 
This is POA. Did we get a reply yet where someone fixes that on his workbench for $1200 in parts and rants about the ripoff that is the engine repair business ?
No need for $1200 in parts. A little Gorilla Glue, some JB Weld and a touch of Bondo will have it good as new.

;)
 
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