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Discussion Starter · #1 ·
I changed my oil this past weekend and upon pouring the old oil in a container to recycle I noticed a fair amount of metal in the bottom of the tray. My car is a 2003 9-5 aero with under 70k. I have regularly changed my oil and kept up with all maintenance. I hope it is not my engine bearings and the foresight of a blow engine.

Any thoughts, recommendations, ideas?
 

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Before someone else says it, you should drop the oil pan to check for sludge in the oil pickup tube (if it hasn't already been done). If there are any metal shavings or crap in there, it will be pretty obvious with the pan dropped.

With such low mileage, if those miles were a lot of short trips, the oil may not have had a chance to get up to temperature which is never a good thing.
The PCV version 6 system should have also been installed on the car.

Good luck, hope it turns out OK.
 

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Can't really see much. If the particles are yellow then they are probably from the turbo bearings (which are bronze). If grey then probably the main and / or big end bearings. If there are silvery bits (and especially if some are crescent shaped), then it's probably steel swarf from the timing chain / sprockets (ditto for balance shaft chain and sprockets).

Regards,
John.
 

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Discussion Starter · #5 ·
The specs are bronze and rather small. My car friends believe that the main rod bearings are beginning to etch and it is only time until the engine seizes.

Are the bearings not bronze as well?
 

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the main and rod bearings are a gray metal (Molybdenum I think) coated on top of copper.

The bearings in the turbo are brass

The chain and gears are steel

the chain guides are plastic


That runs pretty much the list of stuff you might find in the pan
 

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These photos don't tell me much. I would get a glass, put an inch of charcoal lighter fluid in it and then drop the pieces in till you get enough to see.
Fist step, test them with a magnet to eliminate steel. My guess is that they are not steel.
Yet to my knowledge, scored bearings don't come off in little pieces either. I am thinking turbo, even tho you have the TD 04. However, you still got to drop the pan to be sure.
 

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the main and rod bearings are a gray metal (Molybdenum I think) coated on top of copper.
I think it's mostly tin in a matrix of other metals. Molybdenum, antimony, lead, copper, zinc, bismuth, and other metals might or might not be in the alloy, layered on copper then a steel shell.

The bearings in the turbo are brass
I'd be surprised if the metal is brass (copper / zinc), though brass would probably do the job reasonably well. A better choice would be a bronze alloy (copper / tin / other stuff), which is what I think it would probably be.

Regards,
John.
 

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They can do. The bearing alloy comes off in little flakes, probably as a result of the bearing being 'hammered' by the journal.

Mmmmmm, maybe.
 

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Mmmmmm, maybe.
Mike,
I've seen a number of bearing shells where the overlay of bearing material was missing in places and peeling off both it's own parent metal and / or the substrate at the edges of the missing areas, and also where the metal wasn't missing, but you could see cracking and flakes beginning to peel away. I've also seen the flakes themselves in the debris at the bottom of the sump. It's typically grey coloured flakes.

Some mention of it here:

https://www.google.com.au/search?so...e+bearings+#q=damaged+engine+bearings+flaking

And:

http://www.substech.com/dokuwiki/doku.php?id=engine_bearing_failure

Regards,
John.
 

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I just experienced this, the bearings flake apart (either from melting or from being hammered) and the flakes peel off as the metal spills out the sides of the bearing surface.

sort of looks like pieces of aluminum foil but a bit more rigid so they don't clump up into little balls.
 

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Well, I'll be.
So I am guessing with that number of miles he has a sludge issue.
My 01 wagon I purchased some years ago with a replacement motor as the original had sludged/siezed at 75000 miles.
Maybe he can save his motor yet.
 

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I just experienced this, the bearings flake apart (either from melting or from being hammered) and the flakes peel off as the metal spills out the sides of the bearing surface.

sort of looks like pieces of aluminum foil but a bit more rigid so they don't clump up into little balls.
I've never seen one that bad. What you describe does sound like the result of the bearing metal seriously overheating and at least partially melting (running dry probably, so hammered plus overheated by friction and then not cooled by oil flow).

What I've seen has been bearings that looked more or less OK, other than for areas where the metal was pitted, with flaky edges around the pitting, or cracks and small areas where the metal was beginning to lift in what would be flakes when they did fall off.

'Babbit' metal (what the metal of the working surface of plain bearings is called, if it's a compound 'matrix' of different metals and not a homogenous alloy) can be made from a number of differing metals. Different babbit metals might fail in somewhat different manners. If so then babbit metal A might flake under X conditions, but babbit metal B might not flake under X conditions(?).

Typing this it occurs to me that the 'flaky' failure behaviour might be at least partially a product of the babbit metal being a matrix of different metals (i.e. particles of one or more metals embedded in a 'sea' of another metal)? If so then the flaking may initiate at the borders between the differing metals (at a microscopic level, then spread from there), which might be due to differing expansion rates (with heat, and maybe as one metal nears melting point but the other doesn't?), and maybe differing ductility when the metals are loaded beyond their elastic limit (i.e. as they are 'hammered')...?

Regards,
John.
 

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Discussion Starter · #17 ·
Well, I'll be.
So I am guessing with that number of miles he has a sludge issue.
My 01 wagon I purchased some years ago with a replacement motor as the original had sludged/siezed at 75000 miles.
Maybe he can save his motor yet.

If the issue is sludge, how would I go about correcting it so that my engine doesn't seize?
 

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The only sure-fire way to get rid of it is to remove the oil pan/sump from the car and clean it out. when you do there are three o-rings that you should replace. One where the oil strainer plugs into the pan and two on the cross-over pipe that the oil flows through from the pump to the back half of the engine. Order them up with some Anerobic sealant (Loctite 518 or equivalent) and plan on a couple of hours under the car.

There are numerous tutorials in the FAQ section on how to do the job
 
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