Official S65 Bearing Specification/Clearance Wiki

[BMRLVR]

Originally Posted by SenorFunkyPants

I'm no expert by any stretch of the imagination, but the deposits on the piston crown look (to me) more permanent than that which you might expect from a cold start or idling. I would have thought that the way the area free of carbon blends into the heavier areas of deposits in the centre of the crown indicates poor combustion.
And lastly the rough surface appearance of the deposits on all the pistons gives the impression of being subject to micro pitting.

The deposits appear wet to me which would make them hard to read and would make their appearance look different to the camera! The way to read a piston or plug and get a correct reading is to run the engine hard after it is at operating temperature and then shut it down with no idle time whatsoever!

[SenorFunkyPants]

Originally Posted by BMRLVR

The Engine from the SC'ed car has Carillo H-Beam rods in it and I am quite sure that is the reason the bearings are in so much better shape than the stock engine. I have noticed this before but didn't want to add another issue to this thread.

The supercharged engine is producing how much extra load on the rod bearings...40% 50%? Yet shows little bearing wear compared with the stock engine which shows heavy wear at a similar mileage. Attributing that to a change in rod really doesn't work for me. The change in rod is not going to mitigate the extra load exerted on the bearing surface during the combustion cycle.
If the rod change was to be responsible for so such a massive reduction in bearing surface wear then it contradicts the theory that high bearing wear is due to a tight bearing clearance...you can't have it both ways.

Good luck with your engine build...sounds like fun.

[SenorFunkyPants]

Originally Posted by regular guy

This makes me wonder the following. Suppose one of the octane guys blows his motor 50 miles after his warranty expires. The motor blew by throwing a rod out the side of the block and owner picks up the pieces and finds that the connecting rod big end is blue. Which is going to be more likely from the guy who doesn't believe that these clearances are an issue:
The guy stays silent and pays for his own motor believing that the mere presence of low octane gas in his country is the most likely cause of his blown motor and blue connecting rod.
OR
The guy goes into BMW and says "you bastards, we all know you have too little oil clearance and this is well documented and I can point you to the articles and proof. I really think you should replace my motor under a good will gesture."

Another false dichotomy.
And what exactly do you think BMW is going to say to guy#2...
"what is it you say...there is someone on the internet who says BMW don't know crap about engines? Why didn't you say that sooner, have this new engine free on us"
BMW couldn't care less about some theory on the internet no matter how well it is dressed up.

[SenorFunkyPants]

Originally Posted by BMRLVR

The deposits appear wet to me which would make them hard to read and would make their appearance look different to the camera! The way to read a piston or plug and get a correct reading is to run the engine hard after it is at operating temperature and then shut it down with no idle time whatsoever!

Some of the piston crowns do indeed show some trace of oil no doubt picked up during the disassemble but others are dry. This was a car driven to an engine shop for an engine rebuild, no reason to suspect that it wasn't just switched off when it arrived.
It is a bit rich that pictures of piston crowns posted to demonstrate that no detonation was occurring then require some contortions to try and explain the clear evidence of poor combustion and micro pitting.

[Billj747]

Originally Posted by Cool Steel

If you don't want to believe guys with real world experience like this ^ than you can believe BMW:

http://biser3a.com/cars/audi-and-bmw...failures-rate/

The difference? BMW is profit oriented, guys on this forum are simply showing the facts. No profit motivation...

http://www.autoblog.com/2012/10/05/b...astrophic-eng/

Cmon BMW is not perfect by any means....I think everyone is fighting the data because they cant believe that BMW would screw up like this. Well it appears they have and do.

I agree. BMW just like every manufacturer prices their cars for a profit, and to have an allowance to cover maintenance and expected failures within their projections. Manufacturers have a lot of data in terms of failure rates or projected failure rates of various systems within the car and price cars accordingly to cover them. They also price their extended warranties accordingly -which is why extending the warranty of an M3 costs more than a 325i.

So when you buy for your car at the dealership, you're not just paying for parts/labor/profit, but also a certain amount to cover the likelyhood of your car or someone else's to have parts fail during the warranty period.

Car manufacturers are 'big-business' just like any company and if a certain failure rate, even for an expensive motor that is within their 'cushion' of acceptability, they won't even blink despite a known issue causing problems for the second-hand market or cars outside of the warranty period. Once it's beyond their liability, it's not their problem.

0.02

[BMRLVR]

Originally Posted by SenorFunkyPants

Some of the piston crowns do indeed show some trace of oil no doubt picked up during the disassemble but others are dry. This was a car driven to an engine shop for an engine rebuild, no reason to suspect that it wasn't just switched off when it arrived.
It is a bit rich that pictures of piston crowns posted to demonstrate that no detonation was occurring then require some contortions to try and explain the clear evidence of poor combustion and micro pitting.

If you can see "clear evidence" of micro pitting your eyes are better than mine. How many engines have you torn down? Nearly every gasoline engine I have taken apart with any amount of mileage has carbon build up on the piston tops...... It is just the nature of the fuel and combustion process of a gasoline engine, very rarely is complete combustion ever realized hence the need for emission control devices! Also, for max power you want your mixture to be at 12:1 to 13:1, this mixture will result in a bit of carbon buildup from incomplete combustion!

[Yellow Snow]

Originally Posted by Billj747

I agree. BMW just like every manufacturer prices their cars for a profit, and to have an allowance to cover maintenance and expected failures within their projections. Manufacturers have a lot of data in terms of failure rates or projected failure rates of various systems within the car and price cars accordingly to cover them. They also price their extended warranties accordingly -which is why extending the warranty of an M3 costs more than a 325i.

So when you buy for your car at the dealership, you're not just paying for parts/labor/profit, but also a certain amount to cover the likelyhood of your car or someone else's to have parts fail during the warranty period.

Car manufacturers are 'big-business' just like any company and if a certain failure rate, even for an expensive motor that is within their 'cushion' of acceptability, they won't even blink despite a known issue causing problems for the second-hand market or cars outside of the warranty period. Once it's beyond their liability, it's not their problem.

0.02

Fair do's, but those links refer to regular BMW engines, not S derivatives which are made to higher standards.

The second link is to warranty direct who are a major BMW warranty supplier in the UK. It's in their interest to do a bit of scaremongering. The list is for engine related problems in general, not total failures.

[Yellow Snow]

Originally Posted by BMRLVR

The Engine from the SC'ed car has Carillo H-Beam rods in it and I am quite sure that is the reason the bearings are in so much better shape than the stock engine. I have noticed this before but didn't want to add another issue to this thread.

Honestly though, in my opinion the OEM fractured rods big end bore is not staying round under load. In some other bearing photos there are signs of the rod bore not being round....... the one that sticks out in my mind is the one that everyone was jumping on that looked the worse out of the set but had the highest clearance. Couple the distortion of the big end bore with the tight clearance and it gets even worse. I think any person wanting to properly address the issue with their S65 should put a better rod in the car along with adjusting the clearances to something a bit more sensible.

For ref, this is a pic of number 5 rod in that same set of Carillo H beam rods. Look at the wear by the part line.

[SenorFunkyPants]

Originally Posted by BMRLVR

If you can see "clear evidence" of micro pitting your eyes are better than mine. How many engines have you torn down? Nearly every gasoline engine I have taken apart with any amount of mileage has carbon build up on the piston tops...... It is just the nature of the fuel and combustion process of a gasoline engine, very rarely is complete combustion ever realized hence the need for emission control devices! Also, for max power you want your mixture to be at 12:1 to 13:1, this mixture will result in a bit of carbon buildup from incomplete combustion!

I guess we will have to agree to disagree.
Quick question though...taking the picture of piston #8 - are the indents on the right of the crown (by the arrow) for the intake valves?
Thanks

[swamp2]

Originally Posted by BMRLVR

A company like BMW can afford to screw up, but when a career engine builder has a few engines that fail, he looses his reputation and many times his business/job I'm the process. Due to this, the engine builder goes with clearances and specs that he knows will work since he can't afford to cover a $30k bill to replace an engine nearly as easy as a big company like BMW can!

As someone else already pointed out this is nonsense. No company ever wants to screw up and BMW like any other big company spend an enormous amount of money to minimize design errors. Two other very relevant points: It is not so much about the cost of a recall (again which no one wants but will not do if the cost is less to not do so) but the issue is how much does it cost to do it right the fist time? As I've pointed out previously an S65 with larger bearing clearances would have cost less, period. Why? Larger clearances can have larger associated component dimension tolerances which makes manufacturing, inspection and QA all cost less.

Originally Posted by BMRLVR

There may be 50K M3's, but probably only 10% of them are represented here! No figures can be drawn from the total production numbers vs. the amount if failures on M3post.

Not quite. That is precisely why in many previous posts I have constructed rough/order of magnitude/"bracketing" estimates and that number was 0.5%.

[swamp2]

Originally Posted by SenorFunkyPants

The supercharged engine is producing how much extra load on the rod bearings...40% 50%?

The increased load is obviously only from the peak combustion cylinder pressure load increase and then only if the load is higher from combustion load than inertial loads. Again at low rpms combustion loads are smaller, inertial loads low but at high rpms inertial loads grow roughly as the square of the rpm. I don't think combustion loads grow at all that fast. Thus low rpm loads dominated by combustion and high rpm loads dominated by inertia.

[regular guy]

Originally Posted by Yellow Snow

For ref, this is a pic of number 5 rod in that same set of Carillo H beam rods. Look at the wear by the part line.

That's what we would call "Exhibit-A" in the case against your bearing eccentricity measurement claims. I will post "Exhibit-B" when I get some more time.

What did your research tell you about the cause and solution to the wear shown in that photo. BTW, there should be at least two or three more bearings that look just like it.

[regular guy]

Originally Posted by Yellow Snow

As a matter of interest. Take a look at the crank sizes from Reg Guys first page post.

Two used cranks from random cars which could have possibly been manufactured over a few years span and both with different mileages

Both engines are well known to me. Here's the answer.

Crank-1 has already been documented in this thread as S65, ~30000 Miles, Bone Stock, 2008. Crank-2 specs are as follows: S65, ~11000 Miles, Bone Stock, 2008.

[MFKN3]

Why don't people in the US initiate a class action lawsuit? BMW are denying it's a known issue. The US is about the only country with the market size and capacity to sort this issue out.

[aussiem3]

Originally Posted by MFKN3

Why don't people in the US initiate a class action lawsuit? BMW are denying it's a known issue. The US is about the only country with the market size and capacity to sort this issue out.

Very good and a timely point.

[regular guy]

Originally Posted by SenorFunkyPants

What stands out is that the supercharged motor shows far less wear than the stock car...this is surely contrary to expected as the increase in CR and HP should cause significantly higher loads on the bearings during the combustion cycle of the supercharged motor.

Not sure where this factoid came from. The supercharged motor actually had slightly lower compression than stock...not more.

Originally Posted by SenorFunkyPants

So the supercharged motor running with much higher bearing loads but displaying far less bearing wear (than the standard motor), coincidentally never used low octane fuel.
Seems like you have come over to the dark side without even realising.

Tempting, but not a chance. At the end of the day, even your theory still comes back to metal to metal contact when it shouldn't. You've never attempted to explain that. Then you still need to provide an explanation for the failures of bone stock motors with low mileage. Motors like this one: 2013, E92 M3, 6300 miles, bone stock with blue connecting rods.

Originally Posted by SenorFunkyPants

The supercharged engine is producing how much extra load on the rod bearings...40% 50%? Yet shows little bearing wear compared with the stock engine which shows heavy wear at a similar mileage.

I categorized the wear on the supercharged car 04: Moderate. I categorized the wear on the stock engine as 04/05: Moderate. The latter being slightly worse than the former. I noticed 4xsmall inclusions on the supercharged bearings; with 4xsmall and 2xmedium inclusions on the stock motor bearing.

You've given me an idea however. Until now, I never thought of rating them based on how many inclusions and how deep they are. I'll see if I can come up with a more objective scheme. Some of the bearings might switch places if I do (not these however).

If I do the objective rating scheme, I'll be sure to post the methodology so others can chime in with their opinions.

Originally Posted by SenorFunkyPants

This was a car driven to an engine shop for an engine rebuild, no reason to suspect that it wasn't just switched off when it arrived.

Not sure where you got that; it's very far from being accurate. The car was delivered to the shop early May, 2010. The shop (Auto Talent) was very small at the time (they've since moved). Cars had to backed in and out every day to shuffle them around. Cars like this one were moved out of the way in the morning, then back in the shop in the evening. The motor was removed and disassembled on the same day these photos were taken: July 15, 2010. That's 2.5 months worth of in/out/idle.

It is a bit rich that pictures of piston crowns posted to demonstrate that no detonation was occurring then require some contortions to try and explain the clear evidence of poor combustion and micro pitting.

There is no pitting on the pistons whatsoever. Please circle and repost photos of the areas of the pistons to show where you think pitting occurred.

Originally Posted by SenorFunkyPants

Another false dichotomy.
And what exactly do you think BMW is going to say to guy#2...
"what is it you say...there is someone on the internet who says BMW don't know crap about engines? Why didn't you say that sooner, have this new engine free on us"
BMW couldn't care less about some theory on the internet no matter how well it is dressed up.

I don't think the word "dichotomy" means what you think it means.

One respondent in a previous thread from AU mentioned that BMW-AU acknowledged "some type of problem" as it relates to these bearing failures, but wouldn't tell the guy anything more than that. If a customer was in that situation with a blown motor right after warranty, the poster said BMW was prepared to grant a good will gesture.

Even if you didn't know the details I just laid out, I'm pretty sure you knew I was asking an ethics question. It very similar if I asked you if your motor blew and you planned to eat the cost of it knowing you had a tune. Or would you try to hide the tune, return the tune back to stock, then ask BMW for a warranty.

Both are very fair questions. I personally think most would try to get the free motor than stand on their ideals and ethics and eat the cost.

[aussiem3]

Originally Posted by regular guy

One respondent in a previous thread from AU mentioned that BMW-AU acknowledged "some type of problem" as it relates to these bearing failures, but wouldn't tell the guy anything more than that. If a customer was in that situation with a blown motor right after warranty, the poster said BMW was prepared to grant a good will gesture.

I posted that. It will be looked at case-by-case and a goodwill be extended. No details of the issues but when he talked about "bearing problems" I don't whether he was refering to any internally known issue, or the discussions on internet forums like this.

BMW Australia has been extremely good with their goodwill and they have looked after customers well after the warranty has expired. That's why I am relaxed about this issue.

[Cool Steel]

Originally Posted by SenorFunkyPants

Another false dichotomy.
And what exactly do you think BMW is going to say to guy#2...
"what is it you say...there is someone on the internet who says BMW don't know crap about engines? Why didn't you say that sooner, have this new engine free on us"
BMW couldn't care less about some theory on the internet no matter how well it is dressed up.

So what are you saying? That you are so sure that bearing clearance, connecting rod clearance is not the culprit that you are willing to not even try to discuss with BMW the possibility of it, if your engine seizes? ...Your just going to take it on the chin? Say nothing and hope and pray they do you right? ........good luck with that...

Or, if your engine fails and you print this information, sit down with BMW and logically review the data with them, don't you agree that there is a higher probability of a favorable outcome than if you did nothing? Especially, if there is a known potential flaw in the engine that they are hiding. Something is causing these engines to fail, that is not theory.

Don't get me wrong if your driving your car low on oil, supercharging, putting crap gas in it then its your fault you got nothing to stand on.

[regular guy]

Originally Posted by aussiem3

I posted that. It will be looked at case-by-case and a goodwill be extended. No details of the issues but when he talked about "bearing problems" I don't whether he was refering to any internally known issue, or the discussions on internet forums like this.

BMW Australia has been extremely good with their goodwill and they have looked after customers well after the warranty has expired. That's why I am relaxed about this issue.

Thanks for the confirmation. I thought it was you, but when I searched, I couldn't find the quote. I did see how your thoughts on this subject have gone back and forth over time. Absolutely nothing wrong with that; you seem like a very honest and well intentioned guy. I hate it when people try to nail you just because you learn something and change your mind.

[Cool Steel]

Originally Posted by Yellow Snow

Fair do's, but those links refer to regular BMW engines, not S derivatives which are made to higher standards.

The second link is to warranty direct who are a major BMW warranty supplier in the UK. It's in their interest to do a bit of scaremongering. The list is for engine related problems in general, not total failures.

The specific engine design was not the point. Those links were simply to point out that BMW is not infallible. I posted those to open the eyes of those who are unwilling to accept that BMW can make mistakes in the past and so are unwilling to review this data logically and consider it a possibility.

"BMW came seventh from bottom"

If this statement does not open your eyes to the possibility of BMW creating a design flaw than you can google "BMW engine failures" and find different ones...there were many more.

Here is another one...Remember, this information is to open every ones eyes to the fact that BMW is not perfect. So that everyone can accept the research that regularguy did as a possibility and not doubt it simply because you don't want to believe that BMW would do this. Logically, if they make mistakes in other cars they build, why would you think they couldn't possibly make a mistake in the S65 ?

http://members.roadfly.com/jason/m3engines.htm

[MFL]

Originally Posted by MFKN3

Why don't people in the US initiate a class action lawsuit? BMW are denying it's a known issue. The US is about the only country with the market size and capacity to sort this issue out.

I've brought it up several times now. I guess we'll have to wait and see if my bearings outlast my factory warranty.

[Cool Steel]

Originally Posted by MFKN3

Why don't people in the US initiate a class action lawsuit? BMW are denying it's a known issue. The US is about the only country with the market size and capacity to sort this issue out.

Isn't some kind of a petition a more plausible solution? A lawsuit is to negative an action. A petition signed by many and presented to BMW to do research into this issue is something we should do. Our concern would be documented, and if ignored can be used against them if needed in the future that they did nothing.