Official S65 Rod Bearing Condition Example Thread

[deansbimmer]

Originally Posted by ///M Power-Belgium

They show a wave wear pattern . This means that the S65 was running out of balance (and very likely also the crank) suffered from serious internal vibrations.
I agree they look better . But the cause of the wave wear pattern is no good .

I don't know what you're talking about with a wave pattern... None of the bearings I see show any signs of failure due to excessive vibrations.

[dpaul]

Ok, I'm confused

Helmsman, what do you mean by "high level" shells?

///M-Power Belgium, "wave pattern"?

deansbimmer, what do you think about the wear shown by InTgr8r, aswy6, wickz80 or myself? Is it significant or not?

[CSBM5]

Originally Posted by deansbimmer

I don't know what you're talking about with a wave pattern... None of the bearings I see show any signs of failure due to excessive vibrations.

I don't see it either. Poster tends to always be on the attack about bearings it seems.

Many of these recent bearing swaps show OEM bearings still doing fine which doesn't surprise me. Some of these late model pulls above still look fine. Let's hope that long term the BE bearings work well and the mains enjoy more flow through them.

In Rich's case, I'm thinking here's a car with its original owner who has always warmed it up carefully, etc, and that's how a 2008 arrives at over 100k miles with still very serviceable bearings.

[Helmsman]

Originally Posted by dpaul

Ok, I'm confused

Helmsman, what do you mean by "high level" shells?

///M-Power Belgium, "wave pattern"?

deansbimmer, what do you think about the wear shown by InTgr8r, aswy6, wickz80 or myself? Is it significant or not?

Brain slip, meant high mileage.

[///M Power-Belgium]

Originally Posted by deansbimmer

I don't know what you're talking about with a wave pattern... None of the bearings I see show any signs of failure due to excessive vibrations.

OK . It's really strange you don't see it .
Last year I talked with a race engine builder . And I showed him this thread and the blown S65 engine thread . So he saw the S65 bearings and the different wear paterns on the S65 bearings .
I said to him that I noticed sometimes , some strange horizontal lines over the inside width of the bearing shells and always in the middle of the shells !
He said to me....You are correct . I see the *wave wear patern* sometimes on the bearings from supercharged engines . The wave wear patern is caused by internal vibrations and by overload of torque on Turbo and supercharged engines .

And sometimes we can feel with our fingertip the irregularities (bumps) on the bearing surface.
When we rub with a fingertip over this bumps , they actually feel like a wave through the fingertip .
That's why we talk here about the *wave wear patern*
He said also..That the cylinder walls of the S65 and S85 engine are too thin . BMW was rushed by the research of engine weight saving. That's why they are easily susceptible for internal engine vibrations .

Check the horizontal lines in my red square in the picture below. But actually in all eight of the shells you can see this kind of premature wear .
Note : This S65 has only 19K miles on it !

[inTgr8r]

Originally Posted by ///M Power-Belgium

OK . .......................

Check the horizontal lines in my red square in the picture below. But actually in all eight of the shells you can see this kind of premature wear .
Note : This S65 has only 19K miles on it !

Interesting!

At first I wondered if it was just lighting playing tricks.
(I have several rows of exposed fluorescent tube lights in the shop)

I just checked the bearing shells and there are in fact waves as you describe.

[///M Power-Belgium]

Originally Posted by inTgr8r

Interesting!

At first I wondered if it was just lighting playing tricks.
(I have several rows of exposed fluorescent tube lights in the shop)

I just checked the bearing shells and there are in fact waves as you describe.

Yes. I know .
Thank you for the confirmation

[deansbimmer]

Hogwash. If it were a realistic issue, it would be a major topic of concern between actual engineers who focus on the S65...And we'd see a LOT more broken crankshafts and other symptoms actually attributed to vibration. Per a discussion with a bearing vendor I had at SEMA, small visible striations in the babbit layer of the shell are the result of the manufacturing process and lacking mid-process QC which causes inconsistent thickness of the binding layer. They only show as the babbit is worn away and the high/low spots in the binding layer become visible- a non issue for babbit layers that wear normally (i.e. not at all).

[aswy6]

Originally Posted by deansbimmer

Hogwash. If it were a realistic issue, it would be a major topic of concern between actual engineers who focus on the S65...And we'd see a LOT more broken crankshafts and other symptoms actually attributed to vibration. Per a discussion with a bearing vendor I had at SEMA, small visible striations in the babbit layer of the shell are the result of the manufacturing process and lacking mid-process QC which causes inconsistent thickness of the binding layer. They only show as the babbit is worn away and the high/low spots in the binding layer become visible- a non issue for babbit layers that wear normally (i.e. not at all).

Do you really know every single little random thing like that when it comes to S65 engine? I dont think people who make this engines know as much

[admranger]

Originally Posted by aswy6

Do you really know every single little random thing like that when it comes to S65 engine? I dont think people who make this engines know as much

Clearly they didn't or they wouldn't have designed in such piss poor bearing clearances...

[Timujin]

Not too bad.

[Helmsman]

Originally Posted by Timujin

Not too bad.

Year and mileage mate?

[admranger]

Originally Posted by Helmsman

Year and mileage mate?

2010 and 73,xxx are at the bottom of the pic.

[Scharbag]

Originally Posted by Timujin

Not too bad.

For S65, sure. For normal bearings, they are not good.

[GORDON.M3]

Originally Posted by inTgr8r

Guess I should add mine to the list.
Picked up the car late last year and did the bearings as a preemptive service.

I used BE bearings and bolts.
Very happy that I can now start trending the wear.

Attachment 1830778

Holy, those bearings look terrible for 19k miles. I am glad you got to them before they would have failed on you at the track! By the way, my friend sent me pics at Watkins Glen and I saw your car!

[_david]

EU guy here, 3rd owner, just bought it and did the service to be able to sleep at night, 2012 with 168000 km (104k miles). Oil changed at roughly each 20000 km (12k miles).

Ignore the scratches, they were all sitting together in a plastic bag while I drove home.

[tdott]

Originally Posted by Scharbag

For S65, sure. For normal bearings, they are not good.

Agreed.

None posted on this page should be considered "normal" wear. While not excessive, it's still not good.

[jcolley]

It still bugs me when the cylinders are labeled wrong.

[ch4rz]

2011 E90 M3 with 99,010 miles.

Purchased the car with 78,xxx miles as the third owner.

Left are bottom, right are top.

Replaced with VAC bearings if anyone is curious.

[///M Power-Belgium]

Originally Posted by _david

EU guy here, 3rd owner, just bought it and did the service to be able to sleep at night, 2012 with 168000 km (104k miles). Oil changed at roughly each 20000 km (12k miles).

Ignore the scratches, they were all sitting together in a plastic bag while I drove home.

With your 104K miles on it , your bearings actually look pretty good
Interesting to see your 12K miles oil change intervals , while your bearings look pretty decent !
I'm pretty sure . A bearing replacement was not necessary in your situation.

[drrust]

Originally Posted by ch4rz

2011 E90 M3 with 99,010 miles.

Purchased the car with 78,xxx miles as the third owner.

Left are bottom, right are top.

Replaced with VAC bearings if anyone is curious.

One aspect of the wear patterns that puzzles me is that some engines show uniform wear across the cylinders while others show non uniform wear. Is this indicative of rod deflection or other alignment issues?

Only a few posts on people who have replaced bearings more than once on the same motor. The few that I can recall said replacements looked very good. However they didn't compare the multiple sets.

[XKxRome0ox]

2008 e90 M3
seller had oil tested in Sept/Oct 2017 at 54,050 miles
lab said "great report"

i bought the car in May 2018 with 57514 miles
replaced rod bearings at 58,692 miles this week
with BE bearings and ARP bolts


and this is the condition the rod bearings were in
(they're not in any particular order)
i wanted to do it as insurance and for peace for mind
now i'm really glad that i did it