Official S65 Bearing Specification/Clearance Wiki

[regular guy]

Originally Posted by swamp2

Couldn't at least one of the heads typically be saved and both if no pistons failed catastrophically? Under warranty you would most likely get an entirely new "short engine" as BMW calls it, but doing the work out of warranty that might not be the least expensive route.

There's always parts that can be saved. I wasn't thinking of the question from that angle. Hard to say what angle I was thinking in hindsight; was thinking most of the bottom end as "entirely new engine." But I guess you're right...if the heads are fine then you only need a short block, not a long block.

[MrStinky]

OK thanks for the info. There still seems to be a lot of emotion arguining for and against failure being a big issue or there being a clearance issue. What's wrong with some discussion? Most of us aren't engine builders and I was new to the thread and instead of helping me understand you seem to be frustrated. I thought it was a great point someone brought up about the tws via multiple factors including sheering down grade quickly, and the inherently more heat tws as a thicker oil doesn't transfer as easily, in my mind, given tws is already a very light 60, would speak to with all the factors, the tws invivo behaves as a heavier 40 or light 50 when all said and done.
.the difference in oil flow betweena heavy 0w40 like nobil 1 and a light 50weight like sheared and temp retaining oil would be a much smaller flow difference than 0w40 and lubromoly for example which is really normal to heavy 60.

I was only trying to throw uunbias thoughts so I apologize if they are silly but thanks for your input! You've done amazing work with this thread and all are grateful


QUOTE=regular guy;15369909]Or the choice could have been driven by oil sponsorship. We already had one person in here mention that with oil sponsorship, Castrol pays for some certain percent of all engine failures to BMW. I don't remember the exact perfectage, but I seem to remember it was quite a large percentage.



This thread has always been about NA engines over supercharged engines; and it was never about engine failures...but about clearances and measurements and trying to understand why BONE STOCK motors were failing.[/QUOTE]

[SenorFunkyPants]

Originally Posted by DLSJ5

True, but how does one really tell if the excessive wear is oil starvation from a possible tight clearance issue or from too thick an oil?

Does it have to be restricted to just two options?
I can't see how either or both of these alone can account for the wear patterns that can be seen in quite a number of bearing sets from S65 (and S85) engines.
Typically:
Low wear on the bottom bearing.
Excessive wear aligned with high combustion stroke load on the top bearing.
One or two rod bearing sets having far more wear than the rest.

What might be interesting: next time someone pulls apart their engine for a rod bearing change and finds one or two bearing sets with far more wear than the others, would be to check the ECU logs for reports of a much higher number of misfires in those cylinders compared to the rest.

[chris719]

SFP, have to run out so I will check later, but I believe there was a thread linked somewhere in this one that described an engine with a huge number of misfires on 2 cylinders. When they tore it down the worst looking bearings were not those two (could be wrong).

The fact that there appears to be no consistent pattern on which bearing looks the worst is interesting. If not detonation, tolerance "stack-up" could be an issue, as you can see there are a few NA cars that never make it past 30k miles, but if you do, you seem to be fine for quite a while.

This is why I would be nervous about replacing bearings on a working engine using Plastigauge alone.

[SenorFunkyPants]

It was just a thought...I seem to have read quite a few reports of owners having faulty coil packs eventually giving an engine code fault. It occurred that if the integrated coil/anti-knock unit was malfunctioning then the combustion loads in that one cylinder could be higher.
There is this thread:
http://www.m3post.com/forums/showthread.php?t=940520
where plugs apparently hadn't been changed for 47K miles - is that normal?
The owner also ended up having 2 faulty coils replaced.

[flint]

Originally Posted by MrStinky

OK thanks for the info. There still seems to be a lot of emotion arguining for and against failure being a big issue or there being a clearance issue. What's wrong with some discussion? Most of us aren't engine builders and I was new to the thread and instead of helping me understand you seem to be frustrated. I thought it was a great point someone brought up about the tws via multiple factors including sheering down grade quickly, and the inherently more heat tws as a thicker oil doesn't transfer as easily, in my mind, given tws is already a very light 60, would speak to with all the factors, the tws invivo behaves as a heavier 40 or light 50 when all said and done.
.the difference in oil flow betweena heavy 0w40 like nobil 1 and a light 50weight like sheared and temp retaining oil would be a much smaller flow difference than 0w40 and lubromoly for example which is really normal to heavy 60.

I was only trying to throw uunbias thoughts so I apologize if they are silly but thanks for your input! You've done amazing work with this thread and all are grateful


QUOTE=regular guy;15369909]Or the choice could have been driven by oil sponsorship. We already had one person in here mention that with oil sponsorship, Castrol pays for some certain percent of all engine failures to BMW. I don't remember the exact perfectage, but I seem to remember it was quite a large percentage.



This thread has always been about NA engines over supercharged engines; and it was never about engine failures...but about clearances and measurements and trying to understand why BONE STOCK motors were failing.

[/QUOTE]

Hi Longwong

[ase2dais]

Subcribed

[chris719]

http://www.m5board.com/vbulletin/e60...ml#post3177601

This is a supercharged S85 at 94k miles from California with good looking rod bearings (must be all that 91 octane detonation ).

[jcolley]

Originally Posted by chris719

http://www.m5board.com/vbulletin/e60...ml#post3177601

This is a supercharged S85 at 94k miles from California with good looking rod bearings (must be all that 91 octane detonation ).

Are you considering Paul's to be ok wear? He doesn't, but considers it "normal" in line with all of the rest of our S85s that have been changed out.

Not in any way that I buy into the detonation theory...

On the rebuild, his builder opened up the clearance as well.

[swamp2]

Originally Posted by chris719

This is a supercharged S85 at 94k miles from California with good looking rod bearings (must be all that 91 octane detonation ).

Agree with the post (not quote) above. Many engines apparently (not from my personal inspection) such as turbo or supercharged Vettes can be opened up with similar mileage and have bearings that appear almost new. Of course this case it also a good counter example to S85 and S65 "are delicate" or "will explode before 50k mi", etc.

[SenorFunkyPants]

Originally Posted by chris719

This is a supercharged S85 at 94k miles from California with good looking rod bearings (must be all that 91 octane detonation ).

Damn all those stupid Euro S85 and S65 engines for not blowing up....(they must be using different bearings and/or oil ).

[B767capt]

Here is a copy and paste from Troy over on the M5board. He sells used S85's and usually puts new bearings in them so he's always looking for supply. This ought to stir the pot.





don't sell them because I would have to mark it up to sell the parts I guess ~ but I am more than happy to help you with finding the parts you need. The list of parts needed is actually really simple, although the 702/703 bearings are on back order as of last Wednesday. I bought the remaining 55 bearing shell sets in the country or so I was told that...lol. Some were from a cali dealer, Vegas dealer, and another set from somewhere in Miami. ;-)

I was told BMW is going to be changing the 702/703 and moving to yet another bearing part # within the next few months, so they are not really focusing on replenishing the inventory in the USA with the current bearings. We shall see soon enough.

[Rupes]

Originally Posted by chris719

http://www.m5board.com/vbulletin/e60...ml#post3177601

This is a supercharged S85 at 94k miles from California with good looking rod bearings (must be all that 91 octane detonation ).

Do we know what oil was used for the majority of this engines life?

[///M Power-Belgium]

Originally Posted by SenorFunkyPants

Damn all those stupid Euro S85 and S65 engines for not blowing up....(they must be using different bearings and/or oil ).

About stupid Euro.......I'm from Belgium
Please read my post #"89" on this page >http://www.m3post.com/forums/showthr...8#post15428408

[regular guy]

Originally Posted by ///M Power-Belgium

About stupid Euro.......I'm from Belgium
Please read my post #"89" on this page >http://www.m3post.com/forums/showthr...8#post15428408

If you want to bring that comment into this thread, then it's certainly worth mentioning there was a rebuttal that went unanswered. I've quoted it below for convenience. In case you missed it then, please address it now.

Now I'll add to it by saying the same thing I said recently in another thread. At some point the theory has to meet with the empirical evidence seen on the ground. So far, the evidence on the ground contradicts the theoretical guys. In that case, I'll go with evidence on the ground.

Originally Posted by regular guy

I understand you hope he's right. But he's not an engineer, nor a chemist, nor ever seen the problem. Yet he tells you the root cause is low octane fuel in the US and he's never so much as inspected a single failure? Did you ever ask him to explain the failures in the EU?

98 RON is the same as 94 AKI. Most of the US is filled with 93 AKI.

[///M Power-Belgium]

Originally Posted by regular guy

If you want to bring that comment into this thread, then it's certainly worth mentioning there was a rebuttal that went unanswered. I've quoted it below for convenience. In case you missed it then, please address it now.

Now I'll add to it by saying the same thing I said recently in another thread. At some point the theory has to meet with the empirical evidence seen on the ground. So far, the evidence on the ground contradicts the theoretical guys. In that case, I'll go with evidence on the ground.

I know,but how to prove it ? With time and driven miles ?
Than i will maybe out of time > and too late... for the damn bearings !!!
Anyway i hope (for the moment) on the avantage...benefit of the Octane case !
BTW...my S65 is running very well and strong with 31K Miles on it, the only problem that i have is this > # 5 on this page(included video) > http://www.m3post.com/forums/showthr...9#post15529269
And i'm not alone with this problem .....

[Amirsm3]

I spent a good hour reading the OP and then skimmed the rest of the thread. At 91 AKI (AZ has barely any gas stations with 93 AKI), should I be sweating anything? That's all I've filled my cars up with and now I'm curious if it'll have adverse long term effects on my M.

[///M Power-Belgium]

Originally Posted by Amirsm3

I spent a good hour reading the OP and then skimmed the rest of the thread. At 91 AKI (AZ has barely any gas stations with 93 AKI), should I be sweating anything? That's all I've filled my cars up with and now I'm curious if it'll have adverse long term effects on my M.

Like i said above about the Octane..."time will tell".... and sadly than it's maybe damn too late !

[regular guy]

Originally Posted by ///M Power-Belgium

I know,but how to prove it ? With time and driven miles ?
Than i will maybe out of time > and too late... for the damn bearings !!!
Anyway i hope (for the moment) on the avantage...benefit of the Octane case !
BTW...my S65 is running very well and strong with 31K Miles on it, the only problem that i have is this > # 5 on this page(included video) > http://www.m3post.com/forums/showthr...9#post15529269
And i'm not alone with this problem .....

Your sentiments are very similar to what many others have said. However, let me make a couple of points about this.

Some people have "mocked the experts" saying they don't work for BMW and don't know why BMW made these design decisions. That sounds great on the surface. But these same people, much like you've done above, have put your faith in somebody who has absolutely NO experience in ANY of the areas he's commenting. Service advisers don't have the knowledge or expertise to make ANY of these types of comments or draw ANY of these types of conclusions. But for some very odd reasons, many people listen to them simply because their parent company is BMW -- and that's enough for them to believe they are speaking with authority on the subject.

Now compare those guys with our "so-called experts." Our "so-called experts" are completely independent and don't have a vested interest in lying to you, or covering up for their parent company. When an engine fails, these "so-called experts" have to perform failure analysis on the parts, figure out what caused the failure, and devise a remedy. These "so-called experts" have multiple national and international championships behind their racing teams. This is what they do for a living. This IS their area of expertise. Yet people are very quick to dismiss them because they simply don't work for BMW.

As I said earlier, at some point the empirical evidence has to match the theory. As of now, there's a complete mismatch. The "so-called experts" (including the bearing manufacturer themselves) have told you that detonation is not an issue on ANY of these NA engines whose bearings they've inspected. The "so-called experts" have analyzed the same bearings and drawn the same conclusions. But a guy at BMW whose never seen the problem, never seen the bearings, and has absolutely no expertise in this area tells you that detonation and low octane gas is the problem. Believe the BMW guy at your own peril.

Yet for some very odd reason, many people are quick to dismiss the "so-called experts" because they don't work for BMW. Yet they seem overly eager to put their faith in people who don't have ANY expertise in this area, have a vested interest in making their company look good (lying about the outcome), have never analyzed any bearings, and never seen the failure. How far disconnected from the real world must one be to put faith in what some bloke at BMW tells you instead of guys who do this exact type of analysis for a living (and are very good at it)?

[regular guy]

Originally Posted by ///M Power-Belgium

Like i said above about the Octane..."time will tell".... and sadly than it's maybe damn too late !

Isn't six years enough time already?

And in those six years, how many bearing sets have you seen from stock NA engines that show signs of detonation? If I'm not mistaken, the answer is: ZERO. So if six years isn't enough time to tell, then how much more time is needed before we will know? Let's say it's 10 years. After 10 years, let's say one set of bearings shows up with detonation. Is one set of bearings going to be enough for people to say "see, I told you so?" Sadly, I think for some, the answer is yes...one set of bearings after 10 years will be enough.

[Amirsm3]

Originally Posted by ///M Power-Belgium

Like i said above about the Octane..."time will tell".... and sadly than it's maybe damn too late !

Oops, sorry. I had the window open and didn't refresh the thread before I made my post.

I suppose it's just a waiting game. Oh well.

[Amirsm3]

Originally Posted by regular guy

Isn't six years enough time already?

And in those six years, how many bearing sets have you seen from stock NA engines that show signs of detonation? If I'm not mistaken, the answer is: ZERO. So if six years isn't enough time to tell, then how much more time is needed before we will know? Let's say it's 10 years. After 10 years, let's say one set of bearings shows up with detonation. Is one set of bearings going to be enough for people to say "see, I told you so?" Sadly, I think for some, the answer is yes...one set of bearings after 10 years will be enough.

Ah. I guess I skimmed too fast, I thought you were supportive of the lower octane detonation.


I guess there's nothing to worry about on that front.