Official S65 Bearing Specification/Clearance Wiki

[swamp2]

Originally Posted by SenorFunkyPants

The man I've been exchanging emails with at BMW UK forwards any technical questions to the technical support dept at the factory. I cannot imagine any scenario where tech support in Germany would want to give out incorrect information.
If your measurements show a difference in bearing dimensions I can't see the benefit in emailing that information back to BMW - they are hardly going to take some bloke on the internet seriously.

Totally siding with RG here. He's been transparent about his process, is using good equipment and is sharing all of the data. If HIS data show that the bearings are a different size (different clearance really), I will surely believe it. BMW (pretty much like just about any big corporation) has a legal team (or at least have been briefed by legal) about what they can and cannot say about details of any design. Typically they can't say squat. There is just too much potential liability. What part of them changing a critical parameter to fix a possible problem but NOT wanting folks to have evidence that a prior part/design may have had a critical shortcoming? Furthermore, I know if I tried to "chat up" BMW NA and tried to get some inside line to the factory they would pretty well laugh me off of the block. Apparently you have a substantially better pathway for information. That's great but I just don't think you can assume they will share, tell the full truth nor give you access to the folks that really know the answers.

Look, I'm with you, I don't think the installed bearings "generations" will show a statistically significant difference in clearance, but if they do, they do.

[BPMSport]

Originally Posted by swamp2

Totally siding with RG here. He's been transparent about his process, is using good equipment and is sharing all of the data. If HIS data show that the bearings are a different size (different clearance really), I will surely believe it. BMW (pretty much like just about any big corporation) has a legal team (or at least have been briefed by legal) about what they can and cannot say about details of any design. Typically they can't say squat. There is just too much potential liability. What part of them changing a critical parameter to fix a possible problem but NOT wanting folks to have evidence that a prior part/design may have had a critical shortcoming? Furthermore, I know if I tried to "chat up" BMW NA and tried to get some inside line to the factory they would pretty well laugh me off of the block. Apparently you have a substantially better pathway for information. That's great but I just don't think you can assume they will share, tell the full truth nor give you access to the folks that really know the answers.

Look, I'm with you, I don't think the installed bearings "generations" will show a statistically significant difference in clearance, but if they do, they do.

+1

One of our customers sent us a few exchanges regarding oil type to BMW NA, and it seemed like a marketing team was providing (very limited) answers. Only after repeated attempts and carefully chosen sentence structure were the answers provided. It would be difficult to gain access to an engineer or higher up technician through this venue, although it's worth a shot. BMW NA/AG might have different rules and procedures for handing customer inquiries and requests for information such as these.

[SenorFunkyPants]

Originally Posted by swamp2

Totally siding with RG here. He's been transparent about his process, is using good equipment and is sharing all of the data. If HIS data show that the bearings are a different size (different clearance really), I will surely believe it. BMW (pretty much like just about any big corporation) has a legal team (or at least have been briefed by legal) about what they can and cannot say about details of any design. Typically they can't say squat. There is just too much potential liability. What part of them changing a critical parameter to fix a possible problem but NOT wanting folks to have evidence that a prior part/design may have had a critical shortcoming?

I asked the BMW man some questions and reported the answers I got.
As I said "you can take the information any way you like".
AIUI the EU regulations on the use on lead allowed an exemption for "Bearing shells and bushes in engines" which expired "1 July 2011"...so this was a forced change from a bearing with a lead layer to a new harder aluminium composite bearing.
So lets say that BMW were a little economical with the truth and they did indeed add a little extra clearance to the 702/703 bearings.
Which is more likely:
BMW made a U turn in the fundamental design principles of the S85/S65 at the 11th hour of the engines production run to make a bearing dimension change for the last few thousand engines.
Or the new revised bearing needed increased clearance to account for the bearing no longer having a soft 0.0005" sacrificial layer of lead?

[aussiem3]

Originally Posted by SenorFunkyPants

Which is more likely:
BMW made a U turn in the fundamental design principles of the S85/S65 at the 11th hour of the engines production run to make a bearing dimension change for the last few thousand engines.
Or the new revised bearing needed increased clearance to account for the bearing no longer having a soft 0.0005" sacrificial layer of lead?

Two very good and thoughtful points - food for thought!

I would go with 2.

Also, unless it is in a court of law, BMW is not obliged to share technical information with customers. I know we're desperately trying to fish out the information on the clearance but it's not forthcoming.

But my hat off to all those who contributed towards RG's campaign to get to the bottom of this issue.

I think we should await the outcome respectfully as this is going to help the wider community in making some big decisions in the day to come.

[FogCityM3]

Agree, think people need not to lose sight of the fact that they're trying to get closer to the truth (even if the null hypothesis is validated), of which we may all be potential beneficiaries.

Originally Posted by aussiem3

But my hat off to all those who contributed towards RG's campaign to get to the bottom of this issue.

I think we should await the outcome respectfully as this is going to help the wider community in making some big decisions in the day to come.

[regular guy]

Originally Posted by swamp2

No, I simply mean whether you are measuring installed or uninstalled bearings, these brand new bearings (post donations) that you will post similar individual measurements. That is what is required for some statistical analysis.

You will get both. You definitely will get installed measurements. I'm just doing the preliminary work for now...things that I can squeeze in after work. I have next week off to do the rest of the measurements.

I promised to deliver installed measurements at 5-degrees, 45, 90, 135, and 175 degrees. That's what I still plan to deliver.

[regular guy]

Originally Posted by SenorFunkyPants

I asked the BMW man some questions and reported the answers I got.
As I said "you can take the information any way you like".
AIUI the EU regulations on the use on lead allowed an exemption for "Bearing shells and bushes in engines" which expired "1 July 2011"...so this was a forced change from a bearing with a lead layer to a new harder aluminium composite bearing.
So lets say that BMW were a little economical with the truth and they did indeed add a little extra clearance to the 702/703 bearings.
Which is more likely:
BMW made a U turn in the fundamental design principles of the S85/S65 at the 11th hour of the engines production run to make a bearing dimension change for the last few thousand engines.
Or the new revised bearing needed increased clearance to account for the bearing no longer having a soft 0.0005" sacrificial layer of lead?

Like others, I've learned a lot from reading this thread. One of those points learned is that the journal should never touch the bearing under normal operation. The oil creates a film between the gap and prevents the journal from touching the bearing. To me that means that #2 can be discarded as the reason for the bearing thickness change (if the measurements confirm the change). It will be a moot point if the clearance measurements don't change as most people above don't expect them to change. We shall see.

[regular guy]

Here's a small update.

For reference, here's the official BMW TIS procedure for rod bolt tightening with new rod bolts.

Replace screws Screws washed and oiled
1. Jointing torque	6 Nm
2. Setting torque	20 Nm
3. Angle of rotation	130-Degrees
Important 4. Release connecting rod bolts.
5. Jointing torque	6 Nm
6. Setting torque	20 Nm
7. Angle of rotation	130-Degrees
Important 8. Release connecting rod bolts.
9. Jointing torque	6 Nm
10. Setting torque	20 Nm
11. Angle of rotation	130-Degrees

This is what I had to do tonight to fit the new 702/703 bearings with new rod bolts into the connecting rods. Before getting started to fit the new bearings, I had previously measured the bore diameter without any bearings of the properly torqued connecting rods. This gives me a baseline for rod bore dimensions. Then based on my bearing thickness measurements, I carefully selected combinations of bearings and rods to simulate what actual tolerance stack up might be in real life. Six of the bearings were basically identical. But two might be slightly thicker and so I fit one of those pairs to the smallest connecting rod bore, and the other pair to the largest. The remaining six were all nominal fitment. Tomorrow I plan to measure them.

I will also do the same procedure to the 088/089 bearings. I hope to get them all measured tomorrow as well. But it takes so much time to properly stretch the rod bolts, that I'm not sure I'll have enough time to finish the 088/089's tomorrow.

[jbraslins]

Back to oil choice for a second. A lot of discussion was centered on Mobil 1 0w40 as a better alternative to TWS.

Someone I know made a point to say that Shell Rotella T6 5w40 has friction fighting additives (geared towards older design engines), while newer oils are geared towards more modern engines with more roller bearings and therefore use less friction fighting additives. He suggested that if bearing clearance is an issue, that might work better than 0w40.

Does above make any sense? And if does, do you still think 0w40 is better?

Thank you.

[Thom m3]

Having a 2008 M3 competition with about 20.000 km I would like to know what you might hear when a bearing problem is developing.
My car makes a knocking noise from about 4000 rpm in 7th gear and full trottle.
The noise changes to max rpm but remains. My dealer talks about a resonance in the intake. But I have enough experience withe cars and bikes to know that the rattle is from inside the engine.
Is it so that a big end bearing problem is only heard at 1000 rpm ?

[kawasaki00]

Originally Posted by jbraslins

Back to oil choice for a second. A lot of discussion was centered on Mobil 1 0w40 as a better alternative to TWS.

Someone I know made a point to say that Shell Rotella T6 5w40 has friction fighting additives (geared towards older design engines), while newer oils are geared towards more modern engines with more roller bearings and therefore use less friction fighting additives. He suggested that if bearing clearance is an issue, that might work better than 0w40.

Does above make any sense? And if does, do you still think 0w40 is better?

Thank you.

I have recommended both, the T6 does not hold the 40w very long. It falls to a 30 faster than the mobil 0-40. It does have a touch more additive package than the Mobil but not enough to make a discernable difference. If looking at either you could about flip a coin really. Remember the issue is with flow not add pack. The TWS is already good on additives, just need something thinner.

[BPMSport]

One thing I've noticed with the '13 engine I bought VS the 08 motor is that there is much less noise on the initial startup (first second). If I left my 08 for awhile and started it would you hear a racket for a second and then it would immediately go away. The new one doesn't seem to do this. I wonder if there were any other changes that could explain the difference here. I've heard it on a lot of (primarily 08 cars) after they have been sitting for awhile. The starter also sounds completely different than the 08 starter.

[regular guy]

Originally Posted by Mike Benvo

One thing I've noticed with the '13 engine I bought VS the 08 motor is that there is much less noise on the initial startup (first second). If I left my 08 for awhile and started it would you hear a racket for a second and then it would immediately go away. The new one doesn't seem to do this. I wonder if there were any other changes that could explain the difference here. I've heard it on a lot of (primarily 08 cars) after they have been sitting for awhile. The starter also sounds completely different than the 08 starter.

There are two check valves between the heads and block that are intended to keep oil from draining into the pan while the engine is off. This keeps the cams and hydraulic lifters from being oil starved during start up. These check valves are in all 08-13 engines; nothing in that regard has changed.

[regular guy]

All of the "redo" measurements are done. I expect to start posting the results on Friday. No real surprises...depending on your perspective. How's that for an ambiguous cliffhanger?

[///mawana]

Originally Posted by Mike Benvo

One thing I've noticed with the '13 engine I bought VS the 08 motor is that there is much less noise on the initial startup (first second). If I left my 08 for awhile and started it would you hear a racket for a second and then it would immediately go away. The new one doesn't seem to do this. I wonder if there were any other changes that could explain the difference here. I've heard it on a lot of (primarily 08 cars) after they have been sitting for awhile. The starter also sounds completely different than the 08 starter.

Both the starter motor and solenoid switch were updated after 02/2012. Perhaps BMW improved those parts some which might explain the less rackety start-up.

[SenorFunkyPants]

Originally Posted by Thom m3

Having a 2008 M3 competition with about 20.000 km I would like to know what you might hear when a bearing problem is developing.
My car makes a knocking noise from about 4000 rpm in 7th gear and full trottle.
The noise changes to max rpm but remains. My dealer talks about a resonance in the intake. But I have enough experience withe cars and bikes to know that the rattle is from inside the engine.
Is it so that a big end bearing problem is only heard at 1000 rpm ?

If you can hear your engine bearings making a noise then your engine would be unlikely to last many more miles. So if you have done a few hundred miles with the noise then its most likely not coming from the main/rod bearings.

[4corners]

Originally Posted by Mike Benvo

One thing I've noticed with the '13 engine I bought VS the 08 motor is that there is much less noise on the initial startup (first second). If I left my 08 for awhile and started it would you hear a racket for a second and then it would immediately go away. The new one doesn't seem to do this. I wonder if there were any other changes that could explain the difference here. I've heard it on a lot of (primarily 08 cars) after they have been sitting for awhile. The starter also sounds completely different than the 08 starter.

My 08 has made that sound on start up. But it seems like it hasn't since I started using M1 0-40 to top up my 10-60 when it needs a little oil. Maybe a coincidence. Probably my imagination. Could be the new spark plugs too perhaps. Detonation for a second on start up? Maybe the solenoid or starter as mentioned too.

I just keep driving it like a madman.

[MFL]

Class Action Lawsuit yet?!

80 pages of the same stuff.

[BPMSport]

Originally Posted by regular guy

There are two check valves between the heads and block that are intended to keep oil from draining into the pan while the engine is off. This keeps the cams and hydraulic lifters from being oil starved during start up. These check valves are in all 08-13 engines; nothing in that regard has changed.

I had these changed on the 08 motor and it made no discernible difference.

[Minator]

Originally Posted by Mike Benvo

I had these changed on the 08 motor and it made no discernible difference.

Mike...my '13 with a june buld date still makes that dam rattle at cold start like my '09 did.... with break in oil and with TWS made no diff having thiner break -in oil...I now have 2500mi on the engine. sometimes it rattles and makes a light clunk noise too...of course it does not do it all of the time so cannot ever reproduce at dealer..sometimes after 1hrs. of sitting sometimes it wil sit for two days and no noise. I agree that the starter motor seems to spin faster in the '13. So my '13 made this rattle noise from day 1.

[BPMSport]

Originally Posted by Minator

Mike...my '13 with a june buld date still makes that dam rattle at cold start like my '09 did.... with break in oil and with TWS made no diff having thiner break -in oil...I now have 2500mi on the engine. sometimes it rattles and makes a light clunk noise too...of course it does not do it all of the time so cannot ever reproduce at dealer..sometimes after 1hrs. of sitting sometimes it wil sit for two days and no noise. I agree that the starter motor seems to spin faster in the '13. So my '13 made this rattle noise from day 1.

I believe the oil the motor comes with is 10w60.. So it's not any thinner iirc.

The rattle/clack noise I've heard on all of them, 08 to 13 - but that's separate from the noise I was describing which sounds like metal on metal until oil pressure rises.

[regular guy]

Originally Posted by Mike Benvo

I had these changed on the 08 motor and it made no discernible difference.

I'm sorry man, but there's so much here that doesn't make sense to me. You keep bringing up your engine in this thread. That's fine, that's what this thread is for. But that also makes it fair game to discuss the parts that don't make sense.

• You're changing your motor just because it's an '08 even though it runs perfectly fine and nothing wrong with it. That's a $20k expense..."just because."
• Before you stick the old motor in an E46 you're going to rebuild the bottom end and fix the clearances even though it runs perfectly fine and nothing wrong with it. That's a full engine rebuild and another $12k expense "just because."
• Dealer's don't disassemble/reassemble 75% of the motor on a whim to replace check valves if they're not chasing a pretty serious problem. They don't do this on perfectly running motors "just because."
• Your engine sounds like metal-on-metal noise on it when you start it up until oil pressure rises. That's like the carpet in the Big Lebowski -- we finally have something that makes sense and ties the whole room together.

Originally Posted by Mike Benvo

I believe the oil the motor comes with is 10w60.. So it's not any thinner iirc.

The rattle/clack noise I've heard on all of them, 08 to 13 - but that's separate from the noise I was describing which sounds like metal on metal until oil pressure rises.

Post-#9, note-3 of this thread lists the break-in oil of the S85 as of December 2007/January 2008. The break-in oil was 5W30, BMW part number 83 21 0 398 507/508. That page is a direct download from BMW TIS in December 2007/January 2008. I'm curious what break-in oil they use from the factory today. If they changed from these recommendations, then when did they change it?