Particles in sump screen

During oil change today, I found two particles in the sump screen. They are both black and non-magnetic. They look quite different. Here's a picture.

What next step would you suggest to determine the source of these particles?

I'm planning on sending the oil filter out for analysis. And I always send the oil out for analysis.

Thanks for any suggestions,
Michael-

A little history...

Two oil changes ago I found a single small particle in the sump screen and a little dust-like metal in the filter. This is described on the following thread.

http://www.vansairforce.com/community/showthread.php?t=139260

I followed this Lycoming SB and based on the size and amount of material, flew another 25 hours.

https://www.lycoming.com/sites/default/files/Piston Pin Plug Wear Inspection.pdf

After 25 hours I found nothing in the sump screen, and I sent the filter out for analysis and everything was within normal limits.

I've flown another 30 hours since that oil change.

Obviously the size of the particle in the sump screen this time requires diagnosis to determine where the material is coming from.

I'm looking for some advice as to where to start, and based on the particle shapes what a first guess might be.

I ordered a boroscope today and will first have a look at the valves and cylinders to see if that results in any clues.

Thanks for any advice.

Michael-

Gasket left-overs/debris?

By any chance did you change the magneto gaskets and have to scrape the old ones off the back of the accessory case?

P-Mag install...

Gil, I installed a P-Mag, and did scrap off gasket material. The oil change after I installed the P-Mag is when the first particle showed up in the screen. This is my 3rd oil change since the P-Mag install.

Michael-

Plastic pieces off an oil bottle cap bottom ring?

Material analysis

Is there a quick and dirty way to figure out if this material is gasket material? For example, it seems like it might float in water.

Michael-

You said they weren't magnetic - but the top one looks metallic. The bottom picture looks like it could be either carbon chunks or a piece of gasket or sealant material?

bottom pic looks like carbon build up that broke off. It is coked oil and not a typical combustion deposit. How fast do you burn oil? When I glazed a cylinder during break in, I had many chunks in the oil that looked just like that, but smaller in size in just 10 hours. When your oil control ring/cyl wall interface fails, you get that coked oil around the lower circumference of the piston and it regularly breaks off and goes to the sump. It doesn't adhere strongly like combustion deposits. Coked oil deposits typically crush/flake with just finger pressure.

Top pic is too hard to tell without more angles. You can put it in muratic acid. If it starts to fiz in a few minutes, it is likely aluminum. In that case you'll need to figure out where it came from and it isn't good. It is likely more coked oil. The deposits also from in the half moon depressions on the sides of the piston. The shape makes me think that is where it formed, though I suppose it could fall through the small clearance. If it is a carbon deposit, you will be able to easily crack it with your fingers. Metal will bend, not crack. It's shape leads me to believe it is not metal. It is not round and most things of that general shape in an engine, that could break off, would be round.

Larry

Oil burn

I burn 1 quart oil in 25 hours.

My guess is that both are gasket material from my mag change. I used a razor blade to remove the gasket. It could very easily have created the shaved looking top piece. The top piece is black and shiny on one side much like the gasket was.

I'm going to send these off to AvLab for analysis. I'll report back.

Michael

If they are not metallic just move on, waste of time and money analyzing them IMO.

Not metal...

Until Walt's post, I've been treating these particles with kid gloves. I did not want to change their shape because I thought that could help identify what kind of material they were made of.

After Walt's post I decided to mess with them a little to see if I could eliminate the possibility of them being metal.

After a few seconds, it was obvious that they are not metal or carbon. They are malleable/squishy like plastic. They bend and pop back like plastic. When I bite down on them with my front teeth (new tool) they are malleable and squishy like plastic.

I don't know if Vlad was joking, but they feel almost identical to the plastic from an oil container.

As I said earlier, a few oil changes ago I replaced one of my mags with a p-mag, and one oil change ago I had the other mag overhauled. I think the most likely explanation is that it is gasket material from one of the mag changes.

I will still get my filter analyzed, as I usually do. But I'm considering this case closed.

Thanks for the suggestions!
Michael-

Last Test

Well if the feel like plastic and when you bite down they like plastic....

only thing left to do...

Do they taste like plastic.

Michael Burbidge said:

I will still get my filter analyzed, as I usually do. But I'm considering this case closed.

Thanks for the suggestions!
Michael-

Click to expand...

You really get the filter analyzed? Did you mean the oil?
If so a filter cutter ought to be on your Christmas wish list! Pretty simple procedure to inspect. You probably know that...
Tim Andres

An oil filter analysis is much more than just cutting the filter open and inspecting it. It is similar to an oil analysis in that all the "stuff" in the filter, especially the micron-level debris, is analyzed.

I had a filter analyzed after the oil analysis came it a bit unusual. Might be considered overkill on an every-oil-change basis, but at the first sign of trouble it is a good idea, IMHO

YMMV,

Glad you got to the bottom of your mystery. I change my oil and oil filter every 3 months or 50 hours. I send in my oil filter to be analyzed every other oil change! Overkill, maybe, but it works for me.

Just curious, has anyone every actually sent a Lycoming or Continental engine in for overhaul, or had one torn down, based solely on an oil analysis finding?

My Guess

Pieces of the inside lining of your oil hose? John

jpowell13 said:

Pieces of the inside lining of your oil hose? John

Click to expand...

+1 - the failure surface of second chip looked like rubber, the first, like an o-ring. Hard to tell this far away. Still nothing to bother about, but maybe related to some service. Easy to shear a ring like that with a screw and silicone gasket on the rocker cover. OR some imbedded RTV in a thread. Lots of opportunities. If it is not leaking now, don't worry about the source.

No bounce...

It did not feel like rubber. Rubber would feel...rubbery. Hard to tell with such a small piece, but it did not respond like rubber during the teeth test.

Michael-

Michael Burbidge said:

It did not feel like rubber. Rubber would feel...rubbery. Hard to tell with such a small piece, but it did not respond like rubber during the teeth test.

Michael-

Click to expand...

I'm still voting for mag gasket debris...