Could small metal particles gotten past my piston rings and damage my crank after cleaning pistons?

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I took the head off of my BMW S54 and the block had a lot of carbon buildup. My mechanic friend told me that nylon drill attachments won’t scuff the metal because it’s a softer material than the metal. I took the liberty of removing all the carbon i could and i noticed that a lot of carbon gunk seeped past the piston rings (some of it gets pushed back up when i rotate the engine)

Is the carbon crud along with all the tiny metal particles from scotchbright pad/nylon drill attachment going to damage my crank? Should i take the block out and disassemble and clean everything? 🙄
398AFE30-86DD-4BA0-B496-6671FEB73E40.jpeg
 
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Did you use a scotch brite pad or either one of these, if so you need to strip it and clean everything.
scotchbrite.jpeg
scotch brite.jpg


If it was something like this just spray some parts and carb cleaner around the rings in the cylinder then with engine oil.
Never ever use scotch brite to clean the block mating surface, piston tops, heads or any exposed internal surfaces, the abrasive particles
they shed are small they will not be filtered out by the oil filter and can damage or even ruin the bearing in short order, the carbon is not as much an issue, it can be mostly dissolved.

nylon drill brush.jpeg
 
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Those wheels are the highly abrasive material but in a different format. Personally I would tear it down but if you want to take a chance flush all the cylinders down with kerosene with the oil drain plug out the replace the drain plug and flush it through with a few more rounds of kerosene removing and replacing the drain plug each time to hopefully wash anything out. I would try to get a quart down each cylinder. Then fill each cylinder with oil and let it drain down through the rings. Do not turn the engine over.

Pour kerosene down all the oil passages in the block, pull the lower coolant hose and flush the water passages out with water or it could damage the water pump seals. Its a lot of work but the alternative is removing the engine.
When replacing a gasket just use razor blade carefully or a plastic razor and chemical gasket remover on aluminum to remove the material if there is gasket staining but nothing you can feel with a fingernail its fine leave it.

Carbon is best left alone or if excessive soak it in atf, kroil, liquid wrench, etc overnight and remove what you can with a cloth, thats all, no power tools or pads, wheels, wire rushes, etc.
A little carbon is a good thing, it helps to protect the piston head in case of light pre-ingnition or other events.
 

Astro14

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my friend that is a mechanic for porsche told me it’s the way to go. I didn’t have a second thought until staring at it too long
Your friend is a fool. Putting abrasive dust into an engine (by using abrasives on it) and leaving it there is a great way to destroy it quickly. The silicon carbide particles (which is what was impregnated on the “soft” brushes) are far, far worse than metal particles and they will tear up the engine in short order unless they are completely removed before the first start.
 

wwillson

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my friend that is a mechanic for porsche told me it’s the way to go. I didn’t have a second thought until staring at it too long
I saw an engine in my friends shop that someone at we believe was damaged by abrasive grit from someone cleaning a mating surface.

 
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Scotchbrite debris is extremely abrasive. However, it's anybody's guess how much of that debris got into the ring lands, and can't be washed out. If you don't want to disassemble the engine the best course of action is to spend a lot of time cleaning out the area around the rings. To the point where you can assure yourself that they are clean when you turn the engine over. Not to mention ALL the nearby passages where abrasives could get into the oil and water. Then I'd suggest multiple oil changes at the 5 minute, 1 hour and 5 hour marks.

I'm not saying you will "get away with it". I am saying that I've seen it go both ways. Like anything, with sufficient care to wash away the abrasive, success is much more likely.

Some of the engines that failed are absolutely loaded with abrasives, from careless mechanics who spent zero time cleaning it out.
 
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CleanSump

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Collins Dictionary of the English Language. Another work incorrectly used:
A piston land is a raised area of a piston between piston rings. The flow of gas into the volume formed between the piston land between the first and second piston rings is limited by the top ring.
https://www.collinsdictionary.com/us/dictionary/english/piston-land#:~:text=Definition%20of%20'piston%20land'&text=A%20piston%20land%20is%20a,limited%20by%20the%20top%20ring.

Stuff can get on the lands between the rings or into the grooves.
Lands aren't where piston rings are located, the grooves are.
 
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@UFoh keep in mind oil that is sucked up and pressurized will go through the filter. The debris trapped in the rings might be a bigger deal but the damage seems done. I'd suggest an oil change and call it done...

just my $0.02
 

UFoh

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What’s funny is y’all seem concerned about the rings, I’m honestly not concerned about the pistons, rather the main/rod bearings
 
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What’s funny is y’all seem concerned about the rings, I’m honestly not concerned about the pistons, rather the main/rod bearings
The abrasives will end up between the rings when you try to clean it out, and will end up in the oil anyway, damaging the bearings.
 
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What’s funny is y’all seem concerned about the rings, I’m honestly not concerned about the pistons, rather the main/rod bearings
How do think it is getting down to the sump so the oil pump picks it up sends the abrasive through the oil pump damaging it in the bargain and passes those particles right through the oil filter (no the filter will not catch them) to flood the bearings with abrasive in the oil. Even if you change the oil the abrasives are still going to be in the rings so you need to wash it down (hopefully) and out.
 

Astro14

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What’s funny is y’all seem concerned about the rings, I’m honestly not concerned about the pistons, rather the main/rod bearings
Well, rings matter. They will be the first to be destroyed, and cylinders worn beyond limits, resulting in terrible compression and oil burning. The block will be done. Irreparably damaged.

But you won’t have to worry long, because as the abrasive washes off the cylinder walls, the bearing will be next, and then the engine will frag itself.
 
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