Bearing Update - Replaced at 17,000 Miles

[4dimnzn]

I just bought the car with 17,000 miles and felt that it was best to get in front of this known issue (make it reliable – then go down the tuning path). I had my stock units replaced with BE Bearings, their bolts and new OE motor mounts. As I said in a previous post, I’m no stranger to this – I own two S54 cars (Z3MC Clown Shoe and a Z4MR) and we deal with this issues as well as vanos bolts, seals and a few other things.

Anyways, here’s what the stock ones look like at 17,000 miles

[330ciprem]

Originally Posted by 4dimnzn

I just bought the car with 17,000 miles and felt that it was best to get in front of this known issue (make it reliable – then go down the tuning path). I had my stock units replaced with BE Bearings, their bolts and new OE motor mounts. As I said in a previous post, I’m no stranger to this – I own two S54 cars (Z3MC Clown Shoe and a Z4MR) and we deal with this issues as well as vanos bolts, seals and a few other things.

Anyways, here’s what the stock ones look like at 17,000 miles

I am assuming these are the Tin/Al bearings?

Also, they look decent - correct me if I am wrong?

[SYT_Shadow]

Good job! Glad you got them replaced!

Those don't look good for 17k miles at all

[330ciprem]

Originally Posted by SYT_Shadow

Good job! Glad you got them replaced!

Those don't look good for 17k miles at all

What do you normally look for?

Discolorization? Scratches on the bearings?

[SYT_Shadow]

Originally Posted by 330ciprem

What do you normally look for?

Discolorization? Scratches on the bearings?

these already appear to have scratches on them, material seems to be worn away

[Scharbag]

This is what mine looked like at 27,000 KM (~19,000 miles):



My bearings were lead copper type. For an S65, they look stellar (big scratches were my fault when removing them). For any other production car engine with less than 20K miles, they are not looking good.

Your bearings do show some wear and that is not right with such low milage. For S65 bearings, they look OK.

Cheers,

[Helmsman]

OP, the picture doesn't say much really. Please tell me they look like brand at 17k miles.

[330ciprem]

Ok. Multiple opinions here.

OP can you please better pictures? I am no one to judge but others with much more experience - I want to know what you guys think.

[SYT_Shadow]

at 17k miles they bearings should look perfect. These don't as the surface is scratched/marked

[4dimnzn]

Originally Posted by 330ciprem

Ok. Multiple opinions here.

OP can you please better pictures? I am no one to judge but others with much more experience - I want to know what you guys think.

More photos...

[330ciprem]

Originally Posted by 4dimnzn

More photos...

Thank you! Much appreciated.

[Sephiroth]

Lots of opinions, here is the guide from Clevite on how to judge bearings. For 17k miles those are not great.

http://www.wilmink.nl/Clevite/Clevit..._tech_info.pdf

[Pig Farmer]

Originally Posted by Sephiroth

Lots of opinions, here is the guide from Clevite on how to judge bearings. For 17k miles those are not great.

http://www.wilmink.nl/Clevite/Clevit..._tech_info.pdf

After reading the failure analysis guide and all the possible causes, it's amazing that all bearings don't fail within a few thousand miles. Makes me afraid to let anyone without a hermetically sealed garage and a NASA approved torque wrench change the RBs.

[pbonsalb]

I changed mine with the garage door open. I did use decent torque wrenches. Car still working 4 years later.

[///M Power-Belgium]

Originally Posted by SYT_Shadow

at 17k miles they bearings should look perfect. These don't as the surface is scratched/marked

We/I saw worse . In 2013 , a 2013 with only 6K miles on it had bearing failure . His S65 was lost by shavings , but was covered and replaced by BMW warranty.

[SYT_Shadow]

Originally Posted by Pig Farmer

After reading the failure analysis guide and all the possible causes, it's amazing that all bearings don't fail within a few thousand miles. Makes me afraid to let anyone without a hermetically sealed garage and a NASA approved torque wrench change the RBs.

I use a $400 snap on torque wrench

[SYT_Shadow]

Originally Posted by ///M Power-Belgium

We/I saw worse . In 2013 , a 2013 with only 6K miles on it had bearing failure . His S65 was lost by shavings , but was covered and replaced by BMW warranty.

We've definitely seen worse!

But when he came to the forum and said he wanted to replace his bearings people said he was exaggerating.

We've seen worse. But these still don't look good.

[Shazz]

I wonder how many more miles he could have got though... Sure they are meant to be spotless but what if they had another 40k in them before needing to be replaced?

Does anyone have links to what replaced bearings look like after a couple of thousand miles? Are they spotless or do we just accept that this is a 'perishable' part and replace every 60k?

[4dimnzn]

Risk treatment takes on several forms: mitigate it (fix), accept it (live with it), deny it
or ignore it (last two are essentially the same thing). A whole profession and science exists to manage risk.

Similar debates happen in the S54 community about vanos - less about rod bearings.
M Coupe community it's about the trunk floor separation (called the subframe failure) although the acknowledgement of this risk is pretty universal.
318ti it's about the M44 back of head coolant fitting failure (BTW - this is my my most modded car, least powerful and the most fun to throw around).

When it comes to engines and my teeth I'm the guy who likes to get in front of any risk. Doesn't make me right, but IMO makes my car reliable and I sport a dazzling smile ;-)

[8500RPM]

Originally Posted by Shazz

I wonder how many more miles he could have got though... Sure they are meant to be spotless but what if they had another 40k in them before needing to be replaced?

Does anyone have links to what replaced bearings look like after a couple of thousand miles? Are they spotless or do we just accept that this is a 'perishable' part and replace even 60k?

Its not just the rod bearings you have to worry about, the crank takes a beating also. In bad cases, the worn bearings scratch the crank and can make it unusable.

[Helmsman]

Originally Posted by Pig Farmer

After reading the failure analysis guide and all the possible causes, it's amazing that all bearings don't fail within a few thousand miles. Makes me afraid to let anyone without a hermetically sealed garage and a NASA approved torque wrench change the RBs.

...Clean room and white clothes or it won't be done right. Looking for my shop for RB replacement coming Autumn.

[330ciprem]

Originally Posted by Helmsman

...Clean room and white clothes or it won't be done right. Looking for my shop for RB replacement coming Autumn.

At what miles are you, Helmsman?