[PHOTOS ADDED] Main bearings failure - seized engine, 30 000 miles

[aptwave]

Hi everyone,

I'm the "happy" owner of BMW M3 E92, 2012 production year with only 31 000 miles on it.

And I have main bearing failure which leaded me to seized engine...

It happened on a first gear, after a really light pull, not even passing through 5K RPMs and I already started breaking and my engine got seized.

My engine is not disassembled completely, we just removed oil pan, oil pumps and found failed bearing, so have no idea about crankshaft and engine block condition.

Before doing complete disassembling, I want to ask few questions to the community and to people who already re-built S65B40 engine in the past, after similar failure especially. Just need to fill my expectations of how much it will cost for me to repair engine.

So, the questions are:
- If our crankshaft can be repaired(machined and polished) in case it has scratches on it? Or it should be replaced in 100% of cases?
- If our engine block, place where main bearing sits, can be repaired too?
- If I can get correct bearing/crankshaft clearance with any kind of bearings? I know that there's 3 sizes exist for main bearings, but if it's no enough - if there's any aftermarket bearings or company who can produce them? Or add special coating?

Thank you.

P.S. I'll add some pictures later and will update about engine state and solutions we probably going to go.

[RomanK]

wow... are you sure that is main bearing?

[M3ANMACHINE]

Contact Malek@MRF

[///M Power-Belgium]

Originally Posted by M3ANMACHINE

Contact Malek@MRF

+ 1 for Malek

[GORDON.M3]

If you haven't disassembled the block and inspected it carefully don't jump to conclusions. Main bearing failures are a freak accident on the S65 with low mileage. It is possible but not likely until much higher mileage or unless your car was supercharged. Get the engine inspected before you draw any conclusions.

[aptwave]

Originally Posted by gordon@

If you haven't disassembled the block and inspected it carefully don't jump to conclusions. Main bearing failures are a freak accident on the S65 with low mileage. It is possible but not likely until much higher mileage or unless your car was supercharged. Get the engine inspected before you draw any conclusions.

We have removed oil pan and found bad main bearing - it is spinning together with crankshaft.

So Im trying to understand how much damage it can cause to engine block and crankshaft.

Car is not supercharged and only 30 000 miles on it, but it is out of warranty period already.

Originally Posted by M3ANMACHINE

Contact Malek@MRF

Thank you. I will contact him!

[tdott]

Originally Posted by aptwave

So Im trying to understand how much damage it can cause to engine block and crankshaft.

You need to do a tear down and inspect it to know for sure.

Most of the main bearing failures I've seen resulted in damaged crank, block, rods. But I believe those were where the motor seized. If you are saying the main bearing is spinning on the crank, there might be a chance the block can be saved, but it all depends on how much damage has been done, no one here can tell you that...

[aptwave]

Originally Posted by tdott

You need to do a tear down and inspect it to know for sure.

Most of the main bearing failures I've seen resulted in damaged crank, block, rods. But I believe those were where the motor seized. If you are saying the main bearing is spinning on the crank, there might be a chance the block can be saved, but it all depends on how much damage has been done, no one here can tell you that...

Yes, I know that it need to be inspected. My questions are - if crankshaft and block can be repaired or in most cases it leads to buying new block/crank?

I saw somewhere that crankshaft journals can't be repaired, because there's hard metal goes as the first layer, and soft metal below it. So it can't be repaired even if it has really small scratches and polishing will destroy this top, hard metal layer.

[tdott]

Originally Posted by aptwave

My questions are - if crankshaft and block can be repaired or in most cases it leads to buying new block/crank?

I have not seen or heard of anyone repairing an S65 crank, while it might be possible, I think everyone prefers to source a used/new crank if they plan to keep the engine and run it hard.

[rcracin]

A crank can be repaired if you know a proper machine shop and trust their work.

As for the block, any of the journals are cracked, it can't be repaired. If it isn't cracked, you can line bore it. Again, you need a good machine shop.

[pbonsalb]

If I was on a budget, I would buy a rebuilt engine from deansbimmer with replaced rod and main bearings. If I was not on a budget, I would build a motor with a stroker crank and stronger rods and aftermarket pistons with slightly lower compression for a future supercharger.

Hopefully your motor is ok but you don't know until it is disassembled. If there is a rod or main bearing seizure, the block and/or crank may not be any good. This is very unfortunate for those who experience it. Let us know If your rod bearings are fine but a main bearing seized. Sometimes a failed rod bearing results in metal debris that caused main bearing failure. I replaced my rod bearings but main bearing failures start increasing, I will probably change those preventatively -- maybe when I have the trans off to do the clutch in a couple of years.

[doogee]

Originally Posted by gordon@

Main bearing failures are a freak accident on the S65 with low mileage.

I've seen multiple motors with under 30K miles with significant main bearing wear and one with total failure.

There are far more failures than the online community realizes.

[doogee]

Originally Posted by aptwave

Yes, I know that it need to be inspected. My questions are - if crankshaft and block can be repaired or in most cases it leads to buying new block/crank?

I saw somewhere that crankshaft journals can't be repaired, because there's hard metal goes as the first layer, and soft metal below it. So it can't be repaired even if it has really small scratches and polishing will destroy this top, hard metal layer.

You could get the cracked block repaired. All it takes is money. Anything is fixable.

Will it make sense? Maybe not.

Crankshafts can be repaired no problem depending on the level of damage. "Small scratches" are not a problem to remove.

[GORDON.M3]

Originally Posted by doogee

I've seen multiple motors with under 30K miles with significant main bearing wear and one with total failure.

There are far more failures than the online community realizes.

Ai yai yai! So when can we pull our engines out together doogee

[Nugget]

Mine did a main bearing, I heard it and caught it before it seized but the crank, block and one rod were still toast.
I was going to rebuild with stronger rods and supercharge but sold the car instead.
Still have the rods if you are interested.
http://www.m3post.com/forums/showthread.php?t=1368071

[XIX]

Originally Posted by Nugget

Mine did a main bearing, I heard it and caught it before it seized but the crank, block and one rod were still toast.
I was going to rebuild with stronger rods and supercharge but sold the car instead.
Still have the rods if you are interested.
http://www.m3post.com/forums/showthread.php?t=1368071

What was your mileage Nugget? Anything out of the ordinary about your car or usage ?

[deansbimmer]

Sorry to hear of the failure. Yes I've seen a few of these now.

Crankshafts can be repaired. However, until they become unobtainium it's just easier to buy a good used one. Depending on how bad the damage is, you can go from just cleaning up the journals on a crank polisher, to cutting them and using oversized bearings, to welding up the journals, cutting them, and re-hardening the crank.

Core blocks usable at stock bore are getting close to unobtanium status. I do whatever I can to repair a damaged block. Unfortunately, it's pretty darn tricky to repair a block with a spun main bearing. On every one I've seen, the heat and stress of the process cracks the aluminum block's bearing web. I haven't tried it yet, but I suppose it would be possible to weld it and then have it line bored.

Not a lot of shops in the USA are willing to experiment or risk fixing these blocks or cranks. Every shop I've had experience with, including some of the big name shops everyone raves about here, just junk them in favor of a block that they "know" will work.

[Nugget]

Originally Posted by XIX

What was your mileage Nugget? Anything out of the ordinary about your car or usage ?

90,000 kms.
Not that I was aware of, but I was the second owner didn't own it for that long.
I did have the rod bearings replaced (they weren't the worst I've seen), then this happened six months later.

Originally Posted by deansbimmer

Sorry to hear of the failure. Yes I've seen a few of these now.

Crankshafts can be repaired. However, until they become unobtainium it's just easier to buy a good used one. Depending on how bad the damage is, you can go from just cleaning up the journals on a crank polisher, to cutting them and using oversized bearings, to welding up the journals, cutting them, and re-hardening the crank.

Core blocks usable at stock bore are getting close to unobtanium status. I do whatever I can to repair a damaged block. Unfortunately, it's pretty darn tricky to repair a block with a spun main bearing. On every one I've seen, the heat and stress of the process cracks the aluminum block's bearing web. I haven't tried it yet, but I suppose it would be possible to weld it and then have it line bored.

Not a lot of shops in the USA are willing to experiment or risk fixing these blocks or cranks. Every shop I've had experience with, including some of the big name shops everyone raves about here, just junk them in favor of a block that they "know" will work.

Yeah we weren't going to try and repair either, pics below.
And pics of rod bearings which were replaced six months earlier.

[K-M3]

Originally Posted by deansbimmer

Sorry to hear of the failure. Yes I've seen a few of these now.

Crankshafts can be repaired. However, until they become unobtainium it's just easier to buy a good used one. Depending on how bad the damage is, you can go from just cleaning up the journals on a crank polisher, to cutting them and using oversized bearings, to welding up the journals, cutting them, and re-hardening the crank.

Core blocks usable at stock bore are getting close to unobtanium status. I do whatever I can to repair a damaged block. Unfortunately, it's pretty darn tricky to repair a block with a spun main bearing. On every one I've seen, the heat and stress of the process cracks the aluminum block's bearing web. I haven't tried it yet, but I suppose it would be possible to weld it and then have it line bored.

Not a lot of shops in the USA are willing to experiment or risk fixing these blocks or cranks. Every shop I've had experience with, including some of the big name shops everyone raves about here, just junk them in favor of a block that they "know" will work.

In your experience ... is this another case of main bearing failure after rod bearing replacement AND does a rod bearing replacement ( with extra clearance bearings) lead to increased oil flow through the rod bearings but scavenges oil flow thru the main bearing leading to main bearing failure from oil starvation ??

Clarification .. above is a total noob question , so I apologize if it sounds stupid and is completely illogical . I do not know the oil flow pathways in this engine but of late, there have been a few reports of main bearing failure after rod bearing replacement . Hence the query

[deansbimmer]

Originally Posted by K-M3

In your experience ... is this another case of main bearing failure after rod bearing replacement AND does a rod bearing replacement ( with extra clearance bearings) lead to increased oil flow through the rod bearings but scavenges oil flow thru the main bearing leading to main bearing failure from oil starvation ??

I don't believe that replacing the rod bearings leads to any faster rate of failure for the mains. I think that all S65 mains are wearing abnormally, and that the ones with mains that are going to fail just happen to be failing about now as cars are getting to that mileage sweet spot. The only main failures I've seen in person were on stock blocks with original rod bearings.

I believe this is a clearance issue, compounded by variances in OEM tolerances. This is why some of the tighter built motors fail early on under 30k miles, and why some are lasting for over 100k miles and still going strong. Those high milers were built with clearance specs towards the looser side of BMW's spec. That's why I believe that redesigned bearings with increased clearances like BE are the solution.

[BPMSport]

I have an engine for sale in case you're interested with all refreshed parts.

[Scharbag]

Originally Posted by gordon@

Ai yai yai! So when can we pull our engines out together doogee

Can I come?

WTF have I gotten myself into... 31,000KM on my 2011 (27,400 was PO) and every time I have a little fun I think "will this be the last time?"

These are the days I wish the internet did not exist! Ignorance is bliss...