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Old 06-14-2019, 07:08 PM   #1
kopele
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Default Help with possible piston problem

Hi all,

I did a used oil analysis and it came back with excessive aluminum, iron, and lead content. I stuck a borescope camera in the cylinders and cylinder 1 appears to have oil and tiny pieces of something in it. Any idea what that could be? The other 3 cylinders looked dry.

Thanks for the help!



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Old 06-14-2019, 07:21 PM   #2
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From the pictures, it looks like you just have some blowby. Or are you talking about the particles near the cylinder walls?

What was "excessive" in the UOA?
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Old 06-14-2019, 07:30 PM   #3
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Quote:
Originally Posted by Waddlz View Post
From the pictures, it looks like you just have some blowby. Or are you talking about the particles near the cylinder walls?

What was "excessive" in the UOA?
+1
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Old 06-14-2019, 08:26 PM   #4
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Quote:
Originally Posted by Waddlz View Post
From the pictures, it looks like you just have some blowby. Or are you talking about the particles near the cylinder walls?

What was "excessive" in the UOA?
Aluminum was 111ppm, Iron was 17ppm, Lead was 11ppm. It said average values are 4, 9, and 2 respectively. I thought the particles near the cylinder wall were suspicious, but I have no idea what normal wear looks like. It's a rebuilt engine with 13000 miles on it.

Thanks for the help!
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Old 06-16-2019, 10:57 AM   #5
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Anyone know if the particles in the pictures are normal?
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Old 06-17-2019, 10:01 AM   #6
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Anyway you can stick a clean rag in the hole and hope to get some of those "particles" stuck to the rag so you can pull it out to see how hard they are? Don't want to scare you ahead of time but to me it almost looks like a busted ringland, and those particles are pcs of the ringland. No particles that should be normal. They can get stuck between the piston and cyl wall and rally score up the the walls. Plus you said the other 3 pistons looks dry with no particles?
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Old 06-17-2019, 11:12 AM   #7
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Originally Posted by BlackFighter View Post
Anyway you can stick a clean rag in the hole and hope to get some of those "particles" stuck to the rag so you can pull it out to see how hard they are? Don't want to scare you ahead of time but to me it almost looks like a busted ringland, and those particles are pcs of the ringland. No particles that should be normal. They can get stuck between the piston and cyl wall and rally score up the the walls. Plus you said the other 3 pistons looks dry with no particles?
That's a good idea, I'll try to get some of the particles out.
Would a broken ringland affect compression? I did a compression test a few weeks ago and got 120psi on all cylinders with the engine cold. The other
pistons do look dry without particles.

Piston 2:


Piston 3:


Piston 4:
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Old 06-17-2019, 12:12 PM   #8
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to be honest, it looks fine to me.

When I cracked a ringland, compression test showed 60 psi cold on cylinder 4. 125 on all others.

there MIGHT be some scoring on the 2nd cylinder wall from the picture, but without tearing it down I wouldn't worry about it.

I assume you went with blackstone? While your wear metals seem high, you cant use an UOA to identify a failure. Some people have perfect UOAs and they spin a bearing, and some people have high wear metals for years with 0 issues.

My wifes brand new 2014 WRX was showing 5 ppm silver content at 10k miles. People were telling me "its gonna blow up soon" so i traded it in. Talked to the new owners not to long ago and its got 95k miles and the SB has never been replaced. They've only had to do basic repairs on it.

I had a UOA done in June 2018 and it showed excessive wear. I changed oils to a "thicker more robust" 5w-40 and did another UOA December. I had 40 silver content, 110+ copper, 11 lead etc etc. blackstone flagged my copper but the oil I was using uses copper as an anti-wear additive.

So I stopped doing them, because honestly I'm not going to replace an engine that is running perfectly fine now in the chance it may blow up tomorrow because a UOA said I had high wear metals. UOA are really a tool for checking how well your oil is doing, if its shearing down, if its not holding up(which is what I experienced with motul 5w-40)
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Old 06-17-2019, 02:02 PM   #9
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Quote:
Originally Posted by Waddlz View Post
to be honest, it looks fine to me.

When I cracked a ringland, compression test showed 60 psi cold on cylinder 4. 125 on all others.

there MIGHT be some scoring on the 2nd cylinder wall from the picture, but without tearing it down I wouldn't worry about it.

I assume you went with blackstone? While your wear metals seem high, you cant use an UOA to identify a failure. Some people have perfect UOAs and they spin a bearing, and some people have high wear metals for years with 0 issues.

My wifes brand new 2014 WRX was showing 5 ppm silver content at 10k miles. People were telling me "its gonna blow up soon" so i traded it in. Talked to the new owners not to long ago and its got 95k miles and the SB has never been replaced. They've only had to do basic repairs on it.

I had a UOA done in June 2018 and it showed excessive wear. I changed oils to a "thicker more robust" 5w-40 and did another UOA December. I had 40 silver content, 110+ copper, 11 lead etc etc. blackstone flagged my copper but the oil I was using uses copper as an anti-wear additive.

So I stopped doing them, because honestly I'm not going to replace an engine that is running perfectly fine now in the chance it may blow up tomorrow because a UOA said I had high wear metals. UOA are really a tool for checking how well your oil is doing, if its shearing down, if its not holding up(which is what I experienced with motul 5w-40)
Thanks for the input. I did use Blackstone and their comments suggested the aluminum would be coming from a piston. Over the winter the engine got louder, sounds like piston slap and only goes away with a few minutes of driving. Prior to that piston slap would go away as soon as the engine warmed up. It had a stuck PCV and I could see some oil in the exhaust, so I wasn't sure if that messed anything up. Replaced the PCV and no oil in the exhaust anymore. I have a catch can which doesn't fill up too much. It had a lot of water over the winter, I'm guessing due to the PCV being stuck.

This new sound and the UOA have me worried. The engine seems to run well otherwise and hasn't lost any power.
I have sent all this to my engine builder as well, so far the only thing he said is that cylinder 1 may have suffered detonation.
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Old 06-17-2019, 02:42 PM   #10
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How did the spark plug in Cylinder 1 look?

I would not be surprised if the noise you mention was always there but the UOA has made you more sensitive to noises since the report stated that you may have a problem. If the motor is running and compression is good then I wouldn't worry to much.
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Old 06-17-2019, 05:42 PM   #11
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Yes, you have to be careful using UOA to identify a failure. Unless you tested your oil before and after it is hard to tell where the metal is coming from, and like Waddlz said, different oils can give you different UOA results.

120 psi in all 4 cyl is good news. Do a leak down test just to be sure.
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Old 06-17-2019, 06:55 PM   #12
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Quote:
Originally Posted by Turpid Porpoise View Post
How did the spark plug in Cylinder 1 look?

I would not be surprised if the noise you mention was always there but the UOA has made you more sensitive to noises since the report stated that you may have a problem. If the motor is running and compression is good then I wouldn't worry to much.
Here's a picture of the cylinder 1 spark plug. When I did the compression test about 3 weeks ago the white body of this one was cracked. I may have done it while removing it, but I thought I was being careful. I replaced all 4 plugs and they all look the same to my uneducated eyes.
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Old 06-17-2019, 08:18 PM   #13
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Quote:
Originally Posted by BlackFighter View Post
Yes, you have to be careful using UOA to identify a failure. Unless you tested your oil before and after it is hard to tell where the metal is coming from, and like Waddlz said, different oils can give you different UOA results.

120 psi in all 4 cyl is good news. Do a leak down test just to be sure.
Unfortunately I did not get a UOA when the engine was first built to be able to make a comparison. I will try to get a leak down test done and maybe another compression test for good measure.
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Old 06-20-2019, 02:39 PM   #14
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Hard to tell but the first pictures looked like detonation marks to me. If they don't wipe off that's what I would unfortunately lean towards

Is this a stock engine or rebuild?

Mileage?

Mods, tuner, fuel used?
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Old 06-21-2019, 04:01 PM   #15
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Check that plug very closely. If those are tiny specs of aluminium fused to that porcelain you have a detonation issue.
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Old 06-25-2019, 10:21 AM   #16
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any luck getting those particles out and inspecting them?
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Old 06-26-2019, 08:27 PM   #17
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Originally Posted by Paul View Post
Hard to tell but the first pictures looked like detonation marks to me. If they don’t wipe off that’s what I would unfortunately lean towards

Is this a stock engine or rebuild?

Mileage?

Mods, tuner, fuel used?
Rebuilt engine with +0.25mm forged pistons, 13,500 miles.
Mods: Turbo back exhaust, equal length headers, external waste gate, AEM intake, 1050x injectors, AEM 340lph pump, Radium FPR, TGV deletes, 3 port EBCS, dual catch cans.
Tuner: My dumbass with open source.
Fuel: 93

What do detonation marks look like normally?

Last edited by kopele; 06-26-2019 at 08:34 PM.
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Old 06-26-2019, 08:30 PM   #18
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Originally Posted by ripman View Post
Check that plug very closely. If those are tiny specs of aluminium fused to that porcelain you have a detonation issue.
Can't really tell if it's aluminum specs or something else, I'll try to get a closer look.
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Old 06-26-2019, 08:33 PM   #19
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any luck getting those particles out and inspecting them?
I wasn't able to reach them, I'll try again when I find a better tool or method.
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Old 06-29-2019, 09:59 AM   #20
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Default Help with possible piston problem

Quote:
Originally Posted by kopele View Post



What do detonation marks look like normally?

They can look like little dings/pitting

Here’s a picture from my Audi that shows it well, it had issues with meth kit

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Old 07-03-2019, 11:53 AM   #21
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Originally Posted by Paul View Post
They can look like little dings/pitting

Here's a picture from my Audi that shows it well, it had issues with meth kit]
Oh yeah, I can see how those could be signs of detonation in my first picture.
Thanks for sharing your picture!
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Old 01-22-2020, 11:06 AM   #22
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That was indeed pitting from detonation on piston 1. All pistons have the compression ring side clearance way out of spec. Does anybody know what causes that? I can't find any information about the cause online. Engine has about 15K miles on it. Thanks!
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