Metallic Particles in Engine Oil - BMW S52

[Zipway]

Greetings, everyone,

I recently purchased a 1998 BMW M3 on Bring A Trailer that had an admittedly "sordid" history (the auction comments are quite amusing, by the way). After driving it about 1000 miles I've begun to change all the fluids (the selling dealer's service documentation does not show any fluid changes under their watch). Changing the transmission fluid with UUC's recommendations to reduce lightweight flywheel induced transmission rattle made a huge difference in noise and shifter feel.

Having gotten around to changing the engine oil, I discovered to my dismay that the used oil has a fine but thorough metallic sheen, looking similar to metallic paint (see attached photo).

The day after draining I collected a sample of the used oil after stirring up the bucket it was drained into. I just received my Blackstone analysis back and it shows somewhat elevated aluminum, iron, and copper, but the analyst seems to think this isn't of major concern and I should check back after 3,000 miles (see attached report).

Any thoughts? Am I safe to drive another 3000 miles or is there any further diagnosis I could perform? According to the dealer, the compression test was OK and it's "one of the healthiest S52's they've ever seen" but now I'm not so sure about that sentiment. The car has also recently developed an oil leak on the passenger side of the engine (maybe from the oil pan?) I'm going to be trying to figure this leak out soon, the oil pan doesn't look like an easy job on this car, but I'm not sure what else could be leaking on the passenger side.

Thanks for the help!

 

[JHZR2]

Wow, that looks pretty bad if it's truly metallic. UOA wouldn't pick,up shavings, but I'd think that if there were particles like that, and they were abrading away bearings, Pb would be higher.

 

[OVERKILL]

IIRC, these engines have a reputation for eating rod bearings and if the material is big enough, it won't show up in the UOA. I'd be quite concerned and probably drop the pan and expect to put rod bearings in it.

 

[Zipway]

I was afraid that rod bearings would be the answer. I actually bought this M3 as a long overdue replacement for a 1995 M3 (S50 engine) that I had for a short time about 10 years ago which ended up with a rod-related hole in the engine block. Looks like it's just my fate to replace rod bearings in one of these cars.

If I were to do (or have done) the rod bearings, what other "while you're at it" work would you recommend I prepare to do given the history of the engine?

 

[d00df00d]

Originally Posted by OVERKILL
IIRC, these engines have a reputation for eating rod bearings and if the material is big enough, it won't show up in the UOA. I'd be quite concerned and probably drop the pan and expect to put rod bearings in it.

This generation ate head gaskets, not rod bearings.

But yes, very important to point out that these UOAs don't catch big particles.

 

[edyvw]

Originally Posted by OVERKILL
IIRC, these engines have a reputation for eating rod bearings and if the material is big enough, it won't show up in the UOA. I'd be quite concerned and probably drop the pan and expect to put rod bearings in it.

S52? I thought rod bearings were issue later? Not that it cannot happen.

 

[d00df00d]

Originally Posted by Zipway
I was afraid that rod bearings would be the answer. I actually bought this M3 as a long overdue replacement for a 1995 M3 (S50 engine) that I had for a short time about 10 years ago which ended up with a rod-related hole in the engine block. Looks like it's just my fate to replace rod bearings in one of these cars.

If I were to do (or have done) the rod bearings, what other "while you're at it" work would you recommend I prepare to do given the history of the engine?

First of all,

to BITOG!

There's really no telling where the glitter came from without tearing the engine all the way down. Other than the head gasket (which wouldn't cause this issue in isolation), I don't think this engine has a single likely point of failure the way later M engines do. And even if it did, you'd have no way to know in advance if something else was failing as well.

My advice: First, decide whether you can live with the possibility that the engine might seize or blow up on you at some point. If you can, go ahead and run it with short OCIs and see if it keeps making glitter. If not, tear it down ASAP.

 

[OVERKILL]

Originally Posted by d00df00d
Originally Posted by Zipway
I was afraid that rod bearings would be the answer. I actually bought this M3 as a long overdue replacement for a 1995 M3 (S50 engine) that I had for a short time about 10 years ago which ended up with a rod-related hole in the engine block. Looks like it's just my fate to replace rod bearings in one of these cars.

If I were to do (or have done) the rod bearings, what other "while you're at it" work would you recommend I prepare to do given the history of the engine?

First of all,

to BITOG!

There's really no telling where the glitter came from without tearing the engine all the way down. Other than the head gasket (which wouldn't cause this issue in isolation), I don't think this engine has a single likely point of failure the way later M engines do. And even if it did, you'd have no way to know in advance if something else was failing as well.

My advice: First, decide whether you can live with the possibility that the engine might seize or blow up on you at some point. If you can, go ahead and run it with short OCIs and see if it keeps making glitter. If not, tear it down ASAP.


Solid plan

 

[Bjornviken]

What spec/approvals did your oil carry?

 

[ammolab]

Originally Posted by edyvw
Originally Posted by OVERKILL
IIRC, these engines have a reputation for eating rod bearings and if the material is big enough, it won't show up in the UOA. I'd be quite concerned and probably drop the pan and expect to put rod bearings in it.

S52? I thought rod bearings were issue later? Not that it cannot happen.


Yes, S54 3.2 liter M engines were the power plants with many Rod bearing failures. OA on mine had plenty of lead and copper @ 60,000 miles. Rod bearings bad but $2000 replacement saved my engine.

 

[Revving2Redline]

If its a fun car aside from this then I would try to get it repaired. Im still looking into the 318 or 328's for putting around in.

 

[Chris142]

Is that shiney stuff magnetic?

 

[edyvw]

Originally Posted by ammolab
Originally Posted by edyvw
Originally Posted by OVERKILL
IIRC, these engines have a reputation for eating rod bearings and if the material is big enough, it won't show up in the UOA. I'd be quite concerned and probably drop the pan and expect to put rod bearings in it.

S52? I thought rod bearings were issue later? Not that it cannot happen.


Yes, S54 3.2 liter M engines were the power plants with many Rod bearing failures. OA on mine had plenty of lead and copper @ 60,000 miles. Rod bearings bad but $2000 replacement saved my engine.

Yeah, that was my thought. Not that it cannot happen on any engine.

 

[Lolvoguy]

Originally Posted by OVERKILL
Originally Posted by d00df00d
Originally Posted by Zipway
I was afraid that rod bearings would be the answer. I actually bought this M3 as a long overdue replacement for a 1995 M3 (S50 engine) that I had for a short time about 10 years ago which ended up with a rod-related hole in the engine block. Looks like it's just my fate to replace rod bearings in one of these cars.

If I were to do (or have done) the rod bearings, what other "while you're at it" work would you recommend I prepare to do given the history of the engine?

First of all,

to BITOG!

There's really no telling where the glitter came from without tearing the engine all the way down. Other than the head gasket (which wouldn't cause this issue in isolation), I don't think this engine has a single likely point of failure the way later M engines do. And even if it did, you'd have no way to know in advance if something else was failing as well.

My advice: First, decide whether you can live with the possibility that the engine might seize or blow up on you at some point. If you can, go ahead and run it with short OCIs and see if it keeps making glitter. If not, tear it down ASAP.


Solid plan

I concur. This is the reason why I shyed away from the M's when purchasing my relic below.

As for the oil leak, I agree with that others said about head gaskets. I had an external oil leak from the passenger side front corner of my M20 for years that SLOWLY got worse and worse.
I had several oil pan gasket changes and valve cover gasket changes with little to no improvement. Only once I bit the bullet and had the head removed, cleaned, valve seals replaced etc. did the problem finally go away. I still pinch myself in disbelief that I own a 30+ year old BMW that doesn't burn or leak a drop of fluid. A testament to the design and reliability of these old machines.

 

[d00df00d]

Originally Posted by ammolab
Yes, S54 3.2 liter M engines were the power plants with many Rod bearing failures.

The S62, S85, and S65 are known for excess rod bearing wear, too (though actual failure rates are unclear).

 

[demarpaint]

That's not good. My OCD would probably lead me to drop the oil pan and have a look. My bet is if you cut the OCI's in half, shorter OCIs, the damage is going to occur exactly the same, only you'll see half the glitter per OCI. That might lead some to a false sense of security and cost twice as much for oil and filters.

 

[R1jake]

I would just do a flush with some cheap oil then get some decent stuff in there and drive it a couple thou and see how the oil looks next change. But if you have to do the oil pan gasket you miles well do the lower end bearings while in there.

 

[PimTac]

I'd be curious to know what was in there? Not much chance of that though.

Potassium and sodium might indicate a coolant leak. Both show on your UOA. You might want to check into that as well.

 

[Zipway]

Well it looks like the concensus is "tear it down" - from what I've read, to even drop the oil pan in this car requires pulling the engine (or at least that is the easiest way to get to it).

It's been on my bucket list to rebuild an engine (and while I am a mechanical engineer, we all know that's a far cry from a "mechanic"). I may make a project of it myself - it should be easy enough to get to the rod bearings and see what condition they're in. Other engine work I'm not so confident about, though.

On the other hand, I feel like the shop that owned this car for over a year and treated it as a shop project should have done a bit more due diligence in their preparation for sale - this doesn't seem like the type of problem that develops within 1000 miles of street driving. I've already noticed a number of other inconsistencies between the car and their BAT listing and comments. And them not doing a single fluid change on a car they called "restored" rubs me the wrong way.

Alas... I now need to figure out what to do from here.

 

[PimTac]

This project would make a great thread here.