Official S65 Bearing Specification/Clearance Wiki

[SenorFunkyPants]

Originally Posted by regular guy

Interesting. Earlier you said that you had one and only one email with Clevite. You said you posted the entire response in this post. When did you contact Clevite a second time?

And after that I sent some more emails...feel free to dismiss their response out of hand as before.....

Originally Posted by regular guy

And wouldn't this new Clevite response be consistent with all of the emperical evidence of tolerance stacking hypothesis presented in this thread?

....Unless it agrees with you in which case its probably spot on.

[catpat8000]

Originally Posted by swamp2

Come on folks, all of you who passionately want to know the answer here put your money where your mouth is and chip in, even $10-$20 would help and surely would give r.g. some additional motivation.

As I've said, I'm happy to contribute $$. Before I do, I would like to see the hypothesis we are testing and how we will test it written down. I'd hate to be back here in a couple months arguing about whatever tests were done because we didn't do X, Y, or Z to some expert's satisfaction.

[SenorFunkyPants]

Originally Posted by regular guy

Hey bud, you've played this antagonist game long enough. Instead of calling BS on every single dot and tiddle, maybe you should read the material you're calling BS on.

Noting of course that it was I who pointed out that using data derived from Carrillo rods for OEM bearing clearance was invalid - and also that the same applies to using Carrillo rods to derive data for side clearances issues. That the one single bearing measurements using a new bearing was only 9% out of Clevite spec etc etc.
So not all of it was BS. Some of it perhaps.

Anyway I'm in email contact with a couple of prospects for info on those bearing part numbers...maybe I might get something, maybe not.

[JRV]

Hey guys, so I have been watching this for a couple months now and I have a few burning questions:

1. Does anyone here or know anyone running a lighter oil (0W-40, 5W-40) consistently and has had this rod bearing issue? IDK if anyone would admit this but hope they would.
2. If switching to a lighter oil so it can squeeze in between the tight bearing clearances helps, didnt they recommend TWS because of the risk the oil film on the bearings would not hold during heavy load/high RPM? Sounds like a pick your poison scenario (BMW chose lesser of two evils, hence why TWS has decent cold flow for its SAE rating?) and no matter what maybe its best to replace the bearings once in its lifetime wether BMW admits an issue or not.
3. Is there anything on this subject matter that both sides agree on?

Also, i am happy to contribute $, as catpat8000 says, i just want to know exactly what the test is for and what the goal is. Honesty will bring back more contribution if necessary.

[Yellow Snow]

Originally Posted by regular guy

Hey bud, you've played this antagonist game long enough. Instead of calling BS on every single dot and tiddle, maybe you should read the material you're calling BS on. Didn't I ask you to do that before? It was good advice then, and it's good advice now.

Excuse me, but isn't getting accurate results from any given source what we are looking for here.

On page 1 you said:

Originally Posted by regular guy

Since I posted this, I ordered and received samples of each of these rod bearings including the oversized bearings. Yesterday, I measured and photographed all of the rod bearings.

Rod Bearings:
11 24 7 838 089 Blue, 53.000 mm, +0.000 mm, 0.07890" Thick, Ended
11 24 7 841 703 Blue, 53.000 mm, +0.000 mm, 0.07890" Thick, Replacement for 089 bearing
11 24 7 838 091 Blue, 52.750 mm, +0.250 mm, 0.08370" Thick, Currently available

11 24 7 838 088 Red, 53.000 mm, +0.000 mm, 0.07875" Thick, Ended
11 24 7 841 702 Red, 53.000 mm, +0.000 mm, 0.07875" Thick, Replacement for 088 bearing
11 24 7 838 090 Red, 52.750 mm, +0.250 mm, 0.08370" Thick, Currently available

I have measured the same 702/703 bearings and come up with a size of .07844". That's nearly 5 tenths radial difference on one and 3 tenths on the other. Or roughly 8 tenths on diameter.

Will you be editing your original post or argue in some way that my measurement is flawed? Especially now that it's actually been admitted that the 702/703 bearings are now magically thinner than the 088/089s? (I haven't verified this. They could be exactly the same)

I know this doesn't suit your cause, but it is an error that needs addressing

Will you also be editing the bearing surface hardness test which was also flawed and very misleading?

[Yellow Snow]

Originally Posted by JRV

3. Is there anything on this subject matter that both sides agree on?

Not that I can think of

[DLSJ5]

Originally Posted by Yellow Snow

Not that I can think of

Yes, you will all use 0W40.

Guys, regardless of where you stand, this has been a great discussion, a lot of good info, etc. Keep it up.

[Yellow Snow]

Originally Posted by DLSJ5

Yes, you will all use 0W40.

Guys, regardless of where you stand, this has been a great discussion, a lot of good info, etc. Keep it up.

Not so fast..... I live in the North East of Britain which gets pretty cold at times but I will be sticking firmly with Edge 10w60 all year round.

[DLSJ5]

Originally Posted by Yellow Snow

Not so fast..... I live in the North East of Britain which gets pretty cold at times but I will be sticking firmly with Edge 10w60 all year round.

Damn it!

[kawasaki00]

Originally Posted by Yellow Snow

Excuse me, but isn't getting accurate results from any given source what we are looking for here.

Will you also be editing the bearing surface hardness test which was also flawed and very misleading?

I guess if I am going to get bashed on everything I post with pictures then we are wasting time trying to get money together for anything.

Lets see, I cant use a micrometer, I cant run a hardness tester and I cant fit bearings. Maybe I should just go talk to the boss man and tell him I need to seek a different profession.

[Yellow Snow]

Originally Posted by kawasaki00

I guess if I am going to get bashed on everything I post with pictures then we are wasting time trying to get money together for anything.

Lets see, I cant use a micrometer, I cant run a hardness tester and I cant fit bearings. Maybe I should just go talk to the boss man and tell him I need to seek a different profession.

Sorry Kawasaki. I honestly don't like to bash you but are you saying the bearing face of the 702/703 is 61Hrb?

It could be misleading. Do you not agree?

[regular guy]

Originally Posted by Yellow Snow

Excuse me, but isn't getting accurate results from any given source what we are looking for here.

Yes. Most of us are here for that purpose, you however are not.

I have measured the same 702/703 bearings and come up with a size of .07844". That's nearly 5 tenths radial difference on one and 3 tenths on the other. Or roughly 8 tenths on diameter.

Your measurements are flawed and you refuse to answer simple questions about ensuring the accuracy of your measurements. Why is that? Don't you want accurate information?

Will you be editing your original post or argue in some way that my measurement is flawed? Especially now that it's actually been admitted that the 702/703 bearings are now magically thinner than the 088/089s? (I haven't verified this. They could be exactly the same)

I don't believe in changing quoted comments even if proven wrong. I'd prefer to leave it wrong and add an edit field at the bottom to indicate that the values have changed.

I know this doesn't suit your cause, but it is an error that needs addressing

What would you like addressed? Do you want to know how an inexperienced person's measurements made on the first day he bought and used the instruments came up with different results than an expert in the field who was 3000 miles away under different temperature conditions? Is that what you want addressed?

Be honest, you don't really want anything addressed...do you? If you did, you'd be answering all the questions posed to you...which notably you refuse to answer.

Will you also be editing the bearing surface hardness test which was also flawed and very misleading?

Sorry man. As you've demonstrated many times in this thread, data falsification is your area of expertise. I don't know anything about hardness tests.

But out of curiosity, what exactly are your credentials to speak as an expert on any of these topics? Clearance, hardness tests, etc.? Where do you work? What is your job?

[regular guy]

Originally Posted by Yellow Snow

Not so fast..... I live in the North East of Britain which gets pretty cold at times but I will be sticking firmly with Edge 10w60 all year round.

Aren't you that guy who tunes BMW diesel engines? What are your other areas of expertise?

[Yellow Snow]

Originally Posted by regular guy

Yes. Most of us are here for that purpose, you however are not.



Your measurements are flawed and you refuse to answer simple questions about ensuring the accuracy of your measurements. Why is that? Don't you want accurate information?



I don't believe in changing quoted comments even if proven wrong. I'd prefer to leave it wrong and add an edit field at the bottom to indicate that the values have changed.



What would you like addressed? Do you want to know how an inexperienced person's measurements made on the first day he bought and used the instruments came up with different results than an expert in the field who was 3000 miles away under different temperature conditions? Is that what you want addressed?

Be honest, you don't really want anything addressed...do you? If you did, you'd be answering all the questions posed to you...which notably you refuse to answer.



Sorry man. As you've demonstrated many times in this thread, data falsification is your area of expertise. I don't know anything about hardness tests.

But out of curiosity, what exactly are your credentials to speak as an expert on any of these topics? Clearance, hardness tests, etc.? Where do you work? What is your job?

Did you not see my explanation of how to accurately measure the bearing thickness? It really is quite simple.

If you wan't to quote bearing surface hardness at 61.0 Hrb, that's up to you, but it's not correct.

[regular guy]

Originally Posted by Yellow Snow

I'm not really sure what you can't understand about the correct measurement method shown here.

I'm not sure you understand how flawed this method is. I've repeatedly asked you to explain how you ensure accuracy, and you give lots of words in response but never answer the question.

You lay the bearing on a surface plate. It naturally falls to being dead level which was also verified at the time.

You then run the clock over the lowest part of the bearing which will show it's thickest section which is 90 degrees to parting line. It's pretty simple.

Perhaps UK bearings are thinner and that's why the USA engines are more prone to wear than UK

Perhaps you don't recognize how flawed this method is. So here's what I want you to do to prove it and then tell us what you did to prevent this.

Mount your slip gauge on a 3-axis mill with 4-digit accurate digital readout. Mount the bearing perfectly perpendicular to your slip gauge. Mount it such that the slip gauge will measure the exact center of the bearing. Your bearing mount cannot move or rotate with the mill table and is mounted perfectly level. Place the slip gauge at your minimum measurement point, just like you showed in post #86. Verify your measurements and you are satisfied, then zero the mill table decimal read out.

Now move the mill 0.0001 inch along the X-axis. If you did this test correctly, your slip gauge will have changed by 0.0143 inch on the Y-axis. That's right, a 0.0001 change in the X-axis will cause a 0.0143 inch change on the Y-axis. Do this test to prove it to yourself. Take photos and be sure to post them. Then come back and explain how the method you showed in post #86 was designed to prevent this type of error from occurring.

Originally Posted by Yellow Snow

Did you not see my explanation of how to accurately measure the bearing thickness? It really is quite simple.

If it's so simple, then do this test and report back your results and photos along with your explanation how you prevented this.

[kawasaki00]

Originally Posted by Yellow Snow

Sorry Kawasaki. I honestly don't like to bash you but are you saying the bearing face of the 702/703 is 61Hrb?

It could be misleading. Do you not agree?

No it is not misleading, numbers aside the new bearing is much harder than the original bearing. Here is a article on bearings. They talk about a bearing with a hardness of 90HV which is equal to about 85 on the B scale. It is very expensive but the point is there are plenty of bearings that are in the range I quoted.
http://www.aera.org/engine-professio...iding-failure/
I am not sure what is so hard to comprehend here. The test is of the overall bearing, there is no way to disect each layer and test them independently.

If that is not good enough how about you take a set and get them tested and get back to us. No matter how you slice it the new bearing is much harder than the old one.

[regular guy]

Originally Posted by Yellow Snow

If you wan't to quote bearing surface hardness at 61.0 Hrb, that's up to you, but it's not correct.

What are your credentials to speak as an expert on this topic?

[swamp2]

Originally Posted by Yellow Snow

A couple more points:

Isn't the top bearing wear down to oil drain from top to bottom shell when parked. Then the initial cold start rotation marks the dry top shell.

Also, how could the parting line wear be down to the journal going off centre at cold start. Surely the lemon shape of the bore wouldn't allow the journal to touch the part line.

No ideas, sorry definitely not my area of expertise.

I guess the questions for some others are these.

1. How can a very small "capillary" layer of oil in a journal bearing run out during an overnight or even week long or more park.
2. Does the oil left in the crank passages also drain? It seems it would be fairly easy to prevent this having basically an instantaneous supply available when starting.
3. If these things above are typical in common production engines how is it that so many engines and can new appearing bearings after thousands of cold starts. Could small bearing clearances really be that detrimental to cold starts?

[Yellow Snow]

Originally Posted by kawasaki00

No it is not misleading, numbers aside the new bearing is much harder than the original bearing. Here is a article on bearings. They talk about a bearing with a hardness of 90HV which is equal to about 85 on the B scale. It is very expensive but the point is there are plenty of bearings that are in the range I quoted.
http://www.aera.org/engine-professio...iding-failure/
I am not sure what is so hard to comprehend here. The test is of the overall bearing, there is no way to disect each layer and test them independently.

If that is not good enough how about you take a set and get them tested and get back to us. No matter how you slice it the new bearing is much harder than the old one.

Last time I looked, 90 Vickers was 53Hrb, not 85.

You are now saying the test is of the overall bearing, where as originally you were saying it was the surface coating. This is what will confuse people reading the thread.

What I'm trying to get across is that the Hrb measurement is accomplished with a 1/16th ball being penetrated into the material at 100 kg. The depth of penetration is then measured to give the Hrb value. (A simplified explanation)

If the soft layer is only half a thou (.0005") and mounted on a harder base substance. Please explain to me how you can get an accurate depth measurement which is many times the thickness of the layer that you are trying measure?

If you can't picture this, then imagine taking some 6082 aluminium at 2" thick and compare it's hardness reading to the exact same 6082 at .0005" thick which is mounted on a piece of hard steel.

Would you get the same result? Y/N

[Yellow Snow]

Originally Posted by regular guy

Perhaps you don't recognize how flawed this method is. So here's what I want you to do to prove it and then tell us what you did to prevent this.

Mount your slip gauge on a 3-axis mill with 4-digit accurate digital readout. Mount the bearing perfectly perpendicular to your slip gauge. Mount it such that the slip gauge will measure the exact center of the bearing. Your bearing mount cannot move or rotate with the mill table and is mounted perfectly level. Place the slip gauge at your minimum measurement point, just like you showed in post #86. Verify your measurements and you are satisfied, then zero the mill table decimal read out.

Now move the mill 0.0001 inch along the X-axis. If you did this test correctly, your slip gauge will have changed by 0.0143 inch on the Y-axis. That's right, a 0.0001 change in the X-axis will cause a 0.0143 inch change on the Y-axis. Do this test to prove it to yourself. Take photos and be sure to post them. Then come back and explain how the method you showed in post #86 was designed to prevent this type of error from occurring.



If it's so simple, then do this test and report back your results and photos along with your explanation how you prevented this.

Now that might sound impressive to some folk, but what on Earth are you on about?

Move the X axis one tenth to get a 14 thou rise?? You're nuts! (Unless I've misunderstood your method)

[swamp2]

Originally Posted by regular guy

That's right, a 0.0001 change in the X-axis will cause a 0.0143 inch change on the Y-axis.

If I understand your objection correctly this is entirely incorrect. You are just talking about the error from the curvature of the bearing and not being at the true saddle of the bearing, right?

This problem is solved simply by Pythagoras formula. The height "error" from moving 1/10th (of a thousandths of an inch) is a whopping

0.0000000025" (about 6 x 10^-5 micron)

The reason being is obvious because the circle is basically flat here at these scales.

It takes moving about 0.02" to amount to an error of 1/10th (of a thousandths).

To me how the method is easily accurate is that one can manually "hunt" for the smallest possible number using the natural small spring pressure in the indicator, anywhere within a 40 thou band size will basically give the right answer.

[swamp2]

Originally Posted by catpat8000

As I've said, I'm happy to contribute $$. Before I do, I would like to see the hypothesis we are testing and how we will test it written down. I'd hate to be back here in a couple months arguing about whatever tests were done because we didn't do X, Y, or Z to some expert's satisfaction.

Thanks for the offer. Sounds to me like the next best step is to measure the diameter of installed old gen 8XX bearings. New bearings, new bolts (new or at least measured rods). Whether or not BMW changed the bearing size to add clearance seems pretty key to me. RG can correct this but he already seemed to say the same.