▀▄ eas | S65 Rod Bearing Replacement: An ongoing "Journal"

[Oakleyguy]

Originally Posted by tom @ eas

Blackstone report attached. Obvious high lead/copper readings:



Interesting that no contaminants were found since we were picking bearing fragments from the oil pan after removal.

This is why I love Blackstone! Always use them on all my cars!

[tom @ eas]

Info
Vehicle: 2008 BMW M3, 6MT
Production Date: 06/08
Oil Used: TWS Motorsport 10W-60, no data provided on previous oil change
Mileage: 36,XXX mi
Fuel: 91 Oct
Driving Habits: Mostly highway/street driving, no track use
Oil Analysis: See below

Notes:
First oil change since new ownership. This particular M3 was purchased from a dentist, that simply drove to the office and back. No track use.

Bearings have odd wearing at bearing edges, we've seen this before on other bearings. hi-res pictures can be seen here. Blackstone universal averages are within spec, but claim oil is at 30W levels.

[MrStinky]

Those bearings look absolutely normal for 30-40k miles

[swamp2]

Originally Posted by MrStinky

Those bearings look absolutely normal for 30-40k miles

In an S65 or across a wide range of engines? If the latter is this normal passenger vehicles or only very high specific output sports car engines?

I ask because I suspect for either of the latter it is not normal but I have asked this same question repeatedly to all of the "experts" on bearings and I've never got a single answer.

Of course we've all heard/read about the Ford pickup or old Volvo that achieved 300-500k miles without an internal work. I highly doubt if those motors were to have had their rod bearings examined at 30-40k miles they would look anything like this.

[kawasaki00]

Originally Posted by MrStinky

Those bearings look absolutely normal for 30-40k miles

Sorry but delamination is not normal, either lack of oil, too thick or too hot or a combination or multiple.

[kawasaki00]

Originally Posted by swamp2

In an S65 or across a wide range of engines? If the latter is this normal passenger vehicles or only very high specific output sports car engines?

I ask because I suspect for either of the latter it is not normal but I have asked this same question repeatedly to all of the "experts" on bearings and I've never got a single answer.

Of course we've all heard/read about the Ford pickup or old Volvo that achieved 300-500k miles without an internal work. I highly doubt if those motors were to have had their rod bearings examined at 30-40k miles they would look anything like this.

If the top shells all looked like the bottom right 5 in the above picture I would call that normal but anytime you have a centralized delamination like the rest that indicates a problem. Could be from multiple things but it is not normal, even for softer lead bearings it is still not right.
We have built multiple supercharges LS7 engines ran them for a couple years and then tore them back down. Honestly we could have scotch brited the rod bearings and ran them again. We didnt but they looked totally normal.
I agree with you on the fact we have rebuild engines for employees either sbc or sbf or whatever with 100k miles and they look nowhere that bad. I know it is not apples to apples but still to have that much wear at that mileage is concerning.

[kawasaki00]

Originally Posted by tom @ eas

Info
Vehicle: 2008 BMW M3, 6MT
Production Date: 06/08
Oil Used: TWS Motorsport 10W-60, no data provided on previous oil change
Mileage: 36,XXX mi
Fuel: 91 Oct
Driving Habits: Mostly highway/street driving, no track use
Oil Analysis: See below

Notes:
First oil change since new ownership. This particular M3 was purchased from a dentist, that simply drove to the office and back. No track use.

Bearings have odd wearing at bearing edges, we've seen this before on other bearings. hi-res pictures can be seen here. Blackstone universal averages are within spec, but claim oil is at 30W levels.

Either the machine was wrong at Blackstone or that car did not have TWS in it, no way the viscosity was that low, maybe on the last change it had a 30w installed and the owner did not know it.

[tom @ eas]

Originally Posted by MrStinky

Those bearings look absolutely normal for 30-40k miles

Not what I'd consider normal, by a long shot.

Originally Posted by kawasaki00

Either the machine was wrong at Blackstone or that car did not have TWS in it, no way the viscosity was that low, maybe on the last change it had a 30w installed and the owner did not know it.

We know of a couple of isolated cases of dealers accidentally using 5W30 oil instead of 10W60.

[swamp2]

Originally Posted by kawasaki00

We have built multiple supercharges LS7 engines ran them for a couple years and then tore them back down. Honestly we could have scotch brited the rod bearings and ran them again. We didnt but they looked totally normal.

Great additional and relevant factoid here. Any recollection of how many miles were racked up on any of these builds?

[kawasaki00]

Originally Posted by swamp2

Great additional and relevant factoid here. Any recollection of how many miles were racked up on any of these builds?

One had 55k miles on it, was a built ls7 with vortec blower with meth. It made 1025 on the Dyno, ran for 3 years at local drag strip on occasion but mostly street. Took it apart just to check it out and all looked good. Valve springs were beat up but as you can imagine it lives on the rev limiter a lot due to traction issues

[W///]

Originally Posted by kawasaki00

Last few times I have had my car out the misses was with me so I dont have to worry about anything over about 6k. LOL
You get that phrase "your gonna get a ticket" haha

That just means you guys have to join us for a mountain run

[kawasaki00]

Originally Posted by W///

That just means you guys have to join us for a mountain run

Sounds good to me, enough of this winter crap lol

[4corners]

Hopefully this makes people feel a little better about the bearing issue.

[CSL_E36]

Originally Posted by 4corners

Hopefully this makes people feel a little better about the bearing issue.

Nice report! Even nicer cracking 100k!

[tom @ eas]

Originally Posted by 4corners

Hopefully this makes people feel a little better about the bearing issue.

Very reassuring. Thanks for posting.

[tom @ eas]

In the middle of a rod bearing replacement on a supercharged-prep M3 and noticed something odd on #3 rod bearing (upper):

Info
Vehicle: 2008 BMW M3, DCT
Production Date: 07/08
Oil Used: TWS Motorsport 10W-60, no data provided on previous oil change
Mileage: ~30,XXX mi
Fuel: 91 Oct
Driving Habits: Mostly highway/street driving, no track use

This is plastic wrapping that was left on the bearing during engine assembly, which was enough to provide pressure on the bearing and causing excessive wear on the upper bearing cap as evidenced below.









More info shortly as we look into this further.

[4corners]

Wow

[regular guy]

Originally Posted by tom @ eas

In the middle of a rod bearing replacement on a supercharged-prep M3 and noticed something odd on #3 rod bearing (upper):

Info
Vehicle: 2008 BMW M3, DCT
Production Date: 07/08
Oil Used: TWS Motorsport 10W-60, no data provided on previous oil change
Mileage: ~30,XXX mi
Fuel: 91 Oct
Driving Habits: Mostly highway/street driving, no track use

This is plastic wrapping that was left on the bearing during engine assembly, which was enough to provide pressure on the bearing and causing excessive wear on the upper bearing cap as evidenced below.









More info shortly as we look into this further.

Notice how it created a heat-generated discoloration of the bearing. I've seen a few sets of bearings also with heat-generated hot spots on them. Any idea how thick that piece of plastic is? Any way to get a micrometer on it?

[tom @ eas]

All bearings were pulled, upper shells pictured on top and lower on bottom. No other foreign material or surprises was discovered during the service:



Bearings were replaced with WPC treated 702/703 bearings and ARP rod bolts. Oil sample has been collected and sent to Blackstone, waiting to see results on their end.

[Mrbig]

After bearings and new bolts are used what is a decent or is a break in period really needed ???

[Mrbig]

Anyone ???

[tom @ eas]

Originally Posted by Mrbig

After bearings and new bolts are used what is a decent or is a break in period really needed ???

No break-in is necessary after rod bearing replacement, but it couldn't hurt for ~100mi.

It's a debate that has been going on for years, you'll get different opinions depending on whom you ask.