Official S65 Rod Bearing Condition Example Thread

[Duk996]

Originally Posted by derbo

Performance Technic did mine yesterday at 52k.

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It does look worn out but is this considered highly worn? My car is a 2011 built in 05-2010.

My car is a 2011 march 2010 build with 46k and they looked identical.

[pbonsalb]

Any copper showing? They look typical for lead bearing from these cars but if no copper was showing you probably were not in imminent danger. Still way more wear for under 50k miles than there should be on properly clearanced bearings.

[Green-Eggs]

Originally Posted by dv13

I saw some discussion on this in one of the threads but wasn't sure if anyone had investigated it further. Someone (maybe Malek?) had the thought that the original factory bolts might be the issue. It's an interesting thought. If the bolts were fine at assembly, but slowly lost their crush strength over time (stretching/material expansion? slowly backing out due to vibration??), would this result in a loss of proper shape and ultimately contact with the bearings which leads to failure?

This seems consistent with the data....engines are OK when new (<10k miles), but over time there is increased bearing wear and failure at some point for the worst cases, with variance in failure miles/time probably depending on assembly tolerance differences and engine operating/environmental conditions. It also seems that after bearing replacements and especially with the BE ARP bolts and ensuring a torque to spec that Malek/others have found no wear on the replacement VAC/Clevite bearings after a significant number of miles. Anecdotally, it would be easy to draw the conclusion that the small clearance is not really the issue, more the delta in clearance over time as that clearance degrades due to some other factor.

I'm now hearing a very faint knock on my car at 41k miles that I never heard previously. As listened to with a stethoscope on the oil pan, it sounds like a regular, rhythmic middle frequency knock/tap with engine speed. My thought is that I'm hearing my first signs of bearing contact, which if the bolt theory is correct would start slowly and increase over time until the bearing shape is distorted enough for flush enough contact to spin the bearing.

I'm not an expert on these matters (and pardon my ignorance!), but is there any way to measure this bolt crush/related bearing shape distortion in a meaningful way before the old bearings are removed? I strongly feel that this is a BMW materials/assembly issue that would impact every vehicle to some degree (even the 100k mile vehicles that are OK, for now) and also think that if it's something as "simple," but measurably able to correlate with bolts being defective (for whatever reasons), that it may be more likely to get a remedy from BMW than making the assumption that x% of engines were simply built incorrectly, which is much harder to prove given the various environmental conditions that each of these cars have been through over the past 10 years.

Can anyone with more knowledge on the subject comment? Thank you!

I'm pretty sure all of this has already been hashed out and answered. If you haven't done so already, see this very long thread.
http://www.m3post.com/forums/showthread.php?t=892838

Rod bolts aren't a problem. There isn't any known rod bolt failures. When rod bolts have less clamping force, it opens up and increases the clearance at 90-degrees, not closes it off. You can see those measurements and graphs here:
http://wiki.rcollins.org/core/index..../S85_Rod_Bolts

The rods themselves aren't the problem. When the rods wear out, they also increase clearance at 90-degrees. This has been measured on about 40-50 used rods. If you stay NA, the rods will not exceed their factory specifications. If you go FI, they may exceed specs, but always in the extra clearance direction, not less.

Machining and torquing isn't the problem either. A CNC will always maching the rods and block perfect every time. A robot will torque the rod bolts perfectly every time.

So no, rod bolt clamping force or any of these other issues is not consistent with the data -- not at all. The data shows too little clearance. The measurements show tolerance stacking. When tolerance stacking happens, that's how you end up with engine failures at low mileage. This has been shown on three or four engines that were measured after they were pulled apart. If you haven't seen this already, this link has the specs for all the bearings. You can see factory bearings allow tolerance stacking that will definitely blow a motor.
http://wiki.rcollins.org/core/index....5_Rod_Bearings

[Solo_M_Tech]

Originally Posted by Green-Eggs

I'm pretty sure all of this has already been hashed out and answered. If you haven't done so already, see this very long thread.
http://www.m3post.com/forums/showthread.php?t=892838

Rod bolts aren't a problem. There isn't any known rod bolt failures. When rod bolts have less clamping force, it opens up and increases the clearance at 90-degrees, not closes it off. You can see those measurements and graphs here:
http://wiki.rcollins.org/core/index..../S85_Rod_Bolts

The rods themselves aren't the problem. When the rods wear out, they also increase clearance at 90-degrees. This has been measured on about 40-50 used rods. If you stay NA, the rods will not exceed their factory specifications. If you go FI, they may exceed specs, but always in the extra clearance direction, not less.

Machining and torquing isn't the problem either. A CNC will always maching the rods and block perfect every time. A robot will torque the rod bolts perfectly every time.

So no, rod bolt clamping force or any of these other issues is not consistent with the data -- not at all. The data shows too little clearance. The measurements show tolerance stacking. When tolerance stacking happens, that's how you end up with engine failures at low mileage. This has been shown on three or four engines that were measured after they were pulled apart. If you haven't seen this already, this link has the specs for all the bearings. You can see factory bearings allow tolerance stacking that will definitely blow a motor.
http://wiki.rcollins.org/core/index....5_Rod_Bearings

I read the last article. The author is biased to BE bearings. Outside of that there is a wealth of knowledge.

I checked my bearing clearances when I installed my Calico (sourced through VAC) bearings and OE bolts 26k miles ago, and every single one had 0.002XX clearance, more than factory 088/089 bearings. Contacted VAC and they informed me I got a new batch of revised thickness Clevite bearings. They were not labeled upper and lower, as expected. They also informed me this was normal. I trust their word but Im always skeptical. Hope my engine doesn't eat itself anytime soon.

Im genuinely interested in learning as much as possible about the bearing issue. Simply because every single S54, S65, and S85 I do bearing replacement services on, has an owner with 100k questions about the cause and the process.

Note, 26k miles and 8 track days so far, so good. No signs of possible issues.

[deansbimmer]

For now there will always be "BE bias" until some other source comes in with more data.

To my knowledge, BE or their associates are the only ones who have published any quantity of reliable data or comparatives on S65 bearings. They still measure and assess competing bearings.
Educated readers can make their own assumptions if they don't agree with the author's conclusion, but BE's data is just about all you can find online for S65 specific bearing info.

[Scharbag]

Originally Posted by ham_sammich

I read the last article. The author is biased to BE bearings. Outside of that there is a wealth of knowledge.

I checked my bearing clearances when I installed my Calico (sourced through VAC) bearings and OE bolts 26k miles ago, and every single one had 0.002XX clearance, more than factory 088/089 bearings. Contacted VAC and they informed me I got a new batch of revised thickness Clevite bearings. They were not labeled upper and lower, as expected. They also informed me this was normal. I trust their word but Im always skeptical. Hope my engine doesn't eat itself anytime soon.

Im genuinely interested in learning as much as possible about the bearing issue. Simply because every single S54, S65, and S85 I do bearing replacement services on, has an owner with 100k questions about the cause and the process.

Note, 26k miles and 8 track days so far, so good. No signs of possible issues.

IIRC the author of the article was involved with the group of people that did all the awesome work to create the BE Bearings. So yeah, gunna be BE centric.

That said, the only people that have shared actual details about the S85 and S65 engines are the BE creators. None of the other vendors have ever shared DETAILED information about their "specialty" bearings.

I have nothing for or against VAC, but there are some threads that demonstrate that VAC has not been fully forthcoming on what the actual specs are for their bearings. As for WPC treated, they are stock clearance bearings but seem to be a little thinner due to the process so it was a good stopgap until a proper replacement could be sourced.

People with the BE bearings seem to be pretty happy. I sure hope that SYT_Shadow opens up his engine soon to see how his BE bearings look after a lot of hard miles!!

Cheers,

[Solo_M_Tech]

Originally Posted by Scharbag

IIRC the author of the article was involved with the group of people that did all the awesome work to create the BE Bearings. So yeah, gunna be BE centric.

That said, the only people that have shared actual details about the S85 and S65 engines are the BE creators. None of the other vendors have ever shared DETAILED information about their "specialty" bearings.

I have nothing for or against VAC, but there are some threads that demonstrate that VAC has not been fully forthcoming on what the actual specs are for their bearings. As for WPC treated, they are stock clearance bearings but seem to be a little thinner due to the process so it was a good stopgap until a proper replacement could be sourced.

People with the BE bearings seem to be pretty happy. I sure hope that SYT_Shadow opens up his engine soon to see how his BE bearings look after a lot of hard miles!!

Cheers,

Originally Posted by deansbimmer

For now there will always be "BE bias" until some other source comes in with more data.

To my knowledge, BE or their associates are the only ones who have published any quantity of reliable data or comparatives on S65 bearings. They still measure and assess competing bearings.
Educated readers can make their own assumptions if they don't agree with the author's conclusion, but BE's data is just about all you can find online for S65 specific bearing info.

Originally Posted by Scharbag

IIRC the author of the article was involved with the group of people that did all the awesome work to create the BE Bearings. So yeah, gunna be BE centric.

That said, the only people that have shared actual details about the S85 and S65 engines are the BE creators. None of the other vendors have ever shared DETAILED information about their "specialty" bearings.

I have nothing for or against VAC, but there are some threads that demonstrate that VAC has not been fully forthcoming on what the actual specs are for their bearings. As for WPC treated, they are stock clearance bearings but seem to be a little thinner due to the process so it was a good stopgap until a proper replacement could be sourced.

People with the BE bearings seem to be pretty happy. I sure hope that SYT_Shadow opens up his engine soon to see how his BE bearings look after a lot of hard miles!!

Cheers,

I don't disagree with either point. I've installed a dozen or so sets of the Calico coated bearings in cars over the last year, my own car included and never had an issue. I'm 26k miles into my new bearings. I have a couple installs north of 20k and the rest in the 5_15k range. All still working fully. To outright say the Calico/VAC bearings are bad, is just false. There was even evidence of a supercharged s65 on VAC bearings that was more down and the bearings showed no wear.

The article may be full of information but the information is biased and should be taken with a grain of salt. To call their information reliable is a stretch.

[pbonsalb]

Plus Malek at MRF has probably done 100 sets of the VAC bearings. Any new bearing is better than a worn or bad bearing. My WPC treated stock ones have 30k miles on them. My thought is that how yours look when they come out at the mileage they have is an indication of the tolerance stacking on your motor. Mine were not about to fail at 60k but had wear patches on the uppers. Lowers looked better. No copper showing in main area only at parting lines and a little down the sides. I’ll change again at 120k.

[doogee]

37,000 miles and going on my VAC bearings. I may pull them in the spring to have a look.

[Solo_M_Tech]

Originally Posted by doogee

37,000 miles and going on my VAC bearings. I may pull them in the spring to have a look.

My OE bearings were toast at 90k, Im going to pull my VAC bearings at 50k (140k on the ODO) and replace them again.

[Solo_M_Tech]

Originally Posted by Duk996

My car is a 2011 march 2010 build with 46k and they looked identical.

Clear indication of Oil Contamination on those bearings. Longitudinal scratches are obvious.

[Duk996]

Originally Posted by ham_sammich

Clear indication of Oil Contamination on those bearings. Longitudinal scratches are obvious.

Main bearings had gone, the upper wear patch is typical and the scoring is from the debris coming off the mains.

[Solo_M_Tech]

Originally Posted by Duk996

Main bearings had gone, the upper wear patch is typical and the scoring is from the debris coming off the mains.

Clearly.

[///M Power-Belgium]

Originally Posted by Duk996

Main bearings had gone, the upper wear patch is typical and the scoring is from the debris coming off the mains.

Like usual ,debris and shavings destroy a S65/85 in no time .

[Duk996]

Originally Posted by ham_sammich

Clearly.

Right!....

[admranger]

Originally Posted by ///M Power-Belgium

Like usual, poor decision making by BMW ///M engineers destroy an S65/85 in no time.

I think this sums it up better...

[Green-Eggs]

Originally Posted by ham_sammich

I don't disagree with either point. I've installed a dozen or so sets of the Calico coated bearings in cars over the last year, my own car included and never had an issue. I'm 26k miles into my new bearings. I have a couple installs north of 20k and the rest in the 5_15k range. All still working fully. To outright say the Calico/VAC bearings are bad, is just false.

Anybody who believes there is a S65 rod bearing clearance problem, then coated OEM bearings is the last they should install. If you don't believe there's a clearance problem, then there is no harm in installing them. The VAC Clevite bearings would be a good alternative for people who don't believe there's a clearance issue and want a better bearing than stock. We've steered people in that direction when it was clear they didn't think there was a clearance problem and wanted to keep factory clearances.

There was even evidence of a supercharged s65 on VAC bearings that was more down and the bearings showed no wear.

I believe you're referring to the engine that used the ARP rod bolts with bore distortion that increased clearance at 90-degree. The reason I think that is because this has come up a few times before and it's always pointed to the same post that used the ARP bolts with bore distortion. I wouldn't use it for comparison because of the known problems with bore distortion.

As far as I know, there's only been one set of Calico coated OEM bearings pulled from a vehicle using rod bolts without bolt distortion. It was an NA engine using OEM rod bolts pulled by my shop after 1500 miles. You can see here what they look like and judge for yourself how they look after 1500 miles with rods and bolts that didn't have the extra clearance caused by the rod bore distortion.
http://www.m3post.com/forums/showpos...8&postcount=96

The article may be full of information but the information is biased and should be taken with a grain of salt. To call their information reliable is a stretch.

Going back up a few posts...the link you quoted doesn't point to an article, it points to a wiki page with measurements and graphs. Those measurements were provided by multiple sources and all showed the same thing. They were provided by Dinan, Van Dyne Engineering (Indy-500 winning engine builder), Bert@BE, and a winning NASCAR engine builder. For all of Bert's measurements, there are photos taken of the instruments as they were used to measure -- just to prevent people from saying the data was biased or manipulated. I'm pretty sure those photos of the measurements themselves are posted in the m3post bearing wiki. I don't see how this can be considered biased data, because it's just data.

[Solo_M_Tech]

Originally Posted by Green-Eggs

Anybody who believes there is a S65 rod bearing clearance problem, then coated OEM bearings is the last they should install. If you don't believe there's a clearance problem, then there is no harm in installing them. The VAC Clevite bearings would be a good alternative for people who don't believe there's a clearance issue and want a better bearing than stock. We've steered people in that direction when it was clear they didn't think there was a clearance problem and wanted to keep factory clearances.

I believe you're referring to the engine that used the ARP rod bolts with bore distortion that increased clearance at 90-degree. The reason I think that is because this has come up a few times before and it's always pointed to the same post that used the ARP bolts with bore distortion. I wouldn't use it for comparison because of the known problems with bore distortion.

As far as I know, there's only been one set of Calico coated OEM bearings pulled from a vehicle using rod bolts without bolt distortion. It was an NA engine using OEM rod bolts pulled by my shop after 1500 miles. You can see here what they look like and judge for yourself how they look after 1500 miles with rods and bolts that didn't have the extra clearance caused by the rod bore distortion.
http://www.m3post.com/forums/showpos...8&postcount=96

Going back up a few posts...the link you quoted doesn't point to an article, it points to a wiki page with measurements and graphs. Those measurements were provided by multiple sources and all showed the same thing. They were provided by Dinan, Van Dyne Engineering (Indy-500 winning engine builder), Bert@BE, and a winning NASCAR engine builder. For all of Bert's measurements, there are photos taken of the instruments as they were used to measure -- just to prevent people from saying the data was biased or manipulated. I'm pretty sure those photos of the measurements themselves are posted in the bearing wiki. I don't see how this can be considered biased data, because it's just data.

If the Calico bearings were garbage, my engine( and hundreds of others) would have are itself by now. I used OE bolts during my install. 26k miles and multiple track days and my car is solid.

I don't want you thinking I'm arguing your point. I'm starting a counter argument against the forums biasing consumers away from all options. To me, the wording used to describe each bearing example is biased to BE being the end all solution, to a problem no one has solved. I'm still waiting for one of these master engine builders to show proof of their clearance stacking theory. If it's out there, I'd like to see it.

My stand is simple. By the bearings you feel will give you the longest life. WPC, BE and VAC/Calico are all good options.

I'll be pulling my bearings in a year or so. After that we will know 100% what the condition of VACs bearings are with 40-50k miles.

[oldmanstyle]

Originally Posted by ham_sammich

The article may be full of information but the information is biased and should be taken with a grain of salt. To call their information reliable is a stretch.

It's tiresome watching you dismiss the hard work of others based on nothing but hunches and conjecture. When it comes down to it that's all you have to offer and it betrays your own bias against BE. Why don't you bless us with your theories and some hard data to back it up? The evidence must surely be there since you're bold enough to level these accusations of dishonesty.

[Dave07997S]

The newer VAC Clevite bearings are extra clearance bearings. It was the older ones that were just coated..

From VACs website..

Our VAC Extra Clearance Bearing Sets: Precise construction with extra clearance and specially coated to keep bearing failure at a minimum.
Reap lower temps and less friction in your expensive BMW engine!

[Solo_M_Tech]

Originally Posted by oldmanstyle

It's tiresome watching you dismiss the hard work of others based on nothing but hunches and conjecture. When it comes down to it that's all you have to offer and it betrays your own bias against BE. Why don't you bless us with your theories and some hard data to back it up? The evidence must surely be there since you're bold enough to level these accusations of dishonesty.

You say I dismiss their data. That is incorrect. They haven't proven anything with their data. The sample rate is too small to effectively come to a concrete conclusion. They don't even know with absolute certainty (neither has anyone else for that matter) what the actual cause of premature wear is. Until they can prove their theory, their conclusion is pure conjecture.

It's refreshing to see them making the effort to share their findings. That's how we come to an eventual conclusion. They believe it's insufficient oil clearance, and BE makes their bearings to suit their theory. It's nothing more than that. Theory backed by a very all sample of data. I'd like to see them measure 50 sample , stock engines and come to a conclusion. I believe that to be a significant enough sample size to draw conclusions from.

Here is an example of something I noticed on my last S85 bearing replacement (Or the attempt). Car came to me making zero noise. Owner wanted a bearing service so that's what I started. Checking the rotating assembly prior to disassembly, I noticed that cylinder 4 was off center and noticable wobble side to side. But not up and down. Pulled the cap and the bolts only required 21nM of torque to remove them. Upon further inspection the cap had flared at the parting line and the new bearing did not fit the cap. Engine needed a new connecting rod. Engine had 110k miles and 3 owners. This is just one example, and doesn't hold true of every single S85.

I don't believe that every single engine was assembled exactly the same with identical clearances. Thus a universal solution cannot be found. I've seen bearing examples that showed debris trapped between the bearing and the connecting rod bore, creating a high spot and centralized wear in that spot. Explain that. How do you quantify that into a universal solution? You can't.

In conclusion.
1. BE hasn't proven anything in my opinion. They have provided some data from a small sample size that conveniently backs their speculation.
2. These engines are all a little different and each bearing condition posted here are specific to that engines assembly procedure.
3. In order to fix your specific engine permanently, you would have to assemble, measure, adjust clearances, measure again and repeat until the engine is assembled with spec clearances.
4 Oil selection becomes more critical when you change oil clearances from factory. Especially if you increase Rod bearing clearances, without adjusting the main clearance as well.
5. Stating one company is better than another is false. If you believe your bearing wear was due to insufficient clearance, buy BE or WPC. If you don't, buy stock or VAC. Any new bearing is better than the old ones.

You can hate me all you want, until I see a larger engine sample size backed with consistent data, I'm a skeptic.

[///M Power-Belgium]

Originally Posted by admranger

I think this sums it up better...

Of course I agree . But we can nothing do about it..