DIY: S65 M3 Rod Bearing

[pbonsalb]

I would use an engine support bar. More space for you. You could use a cable puller attached to an overhead beam.

[admranger]

Originally Posted by RaptorTSI

For those who've tackled this before, do you recommend purchasing an engine support bar, or can I use my engine hoist? In other words, do you think the hoist 'legs' will be in the way too much?

Legs will be in the way too much. Buy a support bar. I've done the job 3 times.

[RaptorTSI]

Thanks guys; appreciate the advice. Found a good support bar on Amazon for $60 so I'll go with that.

[bigjae1976]

Originally Posted by RaptorTSI

Thanks guys; appreciate the advice. Found a good support bar on Amazon for $60 so I'll go with that.

Just get the Harbor Freight bar and use a 20% off coupon.

[rymerc]

If anyone in the central ohio needs to borrow an engine support bar, PM me with a few days notice. The harbor freight one works fine.

[tdott]

In South Florida and got an engine support bar if anyone wants to borrow one. PM me.

[DreamTime]

In case I didn't already tell you, you blew my mind with this DIY. Really though... you are amazing. Hope you know

[SYT_Shadow]

Originally Posted by DreamTime

In case I didn't already tell you, you blew my mind with this DIY. Really though... you are amazing. Hope you know

Thanks. Glad to help the community. We've got to keep these S65's running!!!

[DreamTime]

Originally Posted by SYT_Shadow

Thanks. Glad to help the community. We've got to keep these S65's running!!!

Yes! The last naturally aspirated V8 engine put out by BMW...

[Scharbag]

Originally Posted by SYT_Shadow

Thanks. Glad to help the community. We've got to keep these S65's running!!!

Just getting all of my bits and bobs together for this. Should have the last bolts here next week.

Going to have to do this on tall jack stands. Any big issues or items to consider if dropping the subframe completely?

Thanks again for the great writeup!

[SYT_Shadow]

Originally Posted by Scharbag

Just getting all of my bits and bobs together for this. Should have the last bolts here next week.

Going to have to do this on tall jack stands. Any big issues or items to consider if dropping the subframe completely?

Thanks again for the great writeup!

Nothing specific. If you're doing it on jackstands then I do recommend you go ahead and drop the subframe.

[Scharbag]

So I have the subframe off and basically just have to remove the oil pan etc. I just unpacked and cleaned my new BE bearings and unfortunately I think a couple lower shells were damaged in shipping:



I am assuming that I should for sure not use the one on the left and that the one on the right is also suspect.

Please let me know what you think.

Cheers,

[GORDON.M3]

Originally Posted by Scharbag

So I have the subframe off and basically just have to remove the oil pan etc. I just unpacked and cleaned my new BE bearings and unfortunately I think a couple lower shells were damaged in shipping:



I am assuming that I should for sure not use the one on the left and that the one on the right is also suspect.

Please let me know what you think.

Cheers,

When you clean your bearings, use a lint-free, streak-free cloth. You can find them at your homedepot. Don't use microfiber towels as they do have particles that can get on the bearing.

Also make sure you have some Redline assembly lube. Apply on the mating face of the bearing only, not on the back. Make sure the cap and bearing is cleaned with non-chlorinated brake cleaner if you get oil or dirt on them.

Yes I wouldn't install those bearings, those scratches seem pretty deep and past the coating.

[MMMM3]

As a newbie, who has read much about the one weakness of this car, I have a couple of questions:
1. I don't recall reading how much thickness of the bearing surface is being worn...
2. When the bearing is worn and I am talking about smooth wear, hasn't the engine adapted itself to what it "needs"?
3. Once worn, and the tolerances open up, isn't that a good thing as oil flow is no longer "restricted"?
4. How does this wear turn into engine failure? Roughly how many miles does it take to go from the minor wear shown in the fantastic DIY to catastrophe?
5. It seems that no one has put 30k or more miles on a set of replaced bearings so how do we know what has been accomplished?
6. What about the wear on the crankshaft? I, thankfully, don't hear much about that- is that because the crank surface is "infinitely" harder than the RB's?

thanks for the light!

[SYT_Shadow]

Originally Posted by MMMM3

As a newbie, who has read much about the one weakness of this car, I have a couple of questions:
1. I don't recall reading how much thickness of the bearing surface is being worn...
2. When the bearing is worn and I am talking about smooth wear, hasn't the engine adapted itself to what it "needs"?
3. Once worn, and the tolerances open up, isn't that a good thing as oil flow is no longer "restricted"?
4. How does this wear turn into engine failure? Roughly how many miles does it take to go from the minor wear shown in the fantastic DIY to catastrophe?
5. It seems that no one has put 30k or more miles on a set of replaced bearings so how do we know what has been accomplished?
6. What about the wear on the crankshaft? I, thankfully, don't hear much about that- is that because the crank surface is "infinitely" harder than the RB's?

thanks for the light!

The crank is way harder than the bearings, although nowadays the tendency is moving to harder and harder bearings which are more likely to hurt the crank

We don't know how long it takes these bearings to fail once worn, but they shouldn't be worn at all. My 130k mile E46 bearings literally looked better than my 30k mile E92 or my 36k E90. Note the E46M was tracked heavily and used in winter with 10W60.

The S65/85 have extremely out of the norm bearing wear. It's really incredible to see the state of these bearings when opened up. Almost 100% of them look very bad.

A hypothesis done by BE bearings and other engine builders is that the clearance is way smaller than industry average. When comparing against many other engines, these have around half of that clearance. So they've built bearings that take our clearance to industry average. There's a 100 page thread out there where they discuss this and one either believes them or doesn't.
Bearings shouldn't wear and I've never heard of bearings stopping to wear, especially once you've stripped the top layers off which are what is designed to not wear and support the oil/crank interface.

It is true that no 'proof' exists at this point. I've put 40 track days on my E90 and after next season I expect to have 100. I will then update this thread with pictures.

[SYT_Shadow]

Originally Posted by Scharbag

So I have the subframe off and basically just have to remove the oil pan etc. I just unpacked and cleaned my new BE bearings and unfortunately I think a couple lower shells were damaged in shipping:



I am assuming that I should for sure not use the one on the left and that the one on the right is also suspect.

Please let me know what you think.

Cheers,

Send them a pic and they'll help guide you. One of them definitely doesn't look good

[MMMM3]

The big question for me is:
so how does this minute amount of wear turn into engine failure...

what is a bearing "failure"....
I guess that wear on the bearing if transmitted to the crank would be intolerable...

so the outer surface is a hardened surface which once worn will continue to wear at a faster rate?

[SYT_Shadow]

Originally Posted by MMMM3

The big question for me is:
so how does this minute amount of wear turn into engine failure...

what is a bearing "failure"....
I guess that wear on the bearing if transmitted to the crank would be intolerable...

so the outer surface is a hardened surface which once worn will continue to wear at a faster rate?

eventually the soft part of the bearing is gone and you contact the steel base. Then it 'locks' and the engine tears itself apart and you have failure.

Bearings are considered worn once the outer-most layer is gone.
When the engine is off there's no oil pressure and there's metal on metal contact, so the bearing has a softer outer coating that helps the engine to not jam

The coatings are not made to be harder, they are made to prevent wear and capture oil better for lubrication

[MMMM3]

bearings self welding themselves to the crank from wearing through the wear surface?

WOW!

[doogee]

Those BE Bearings look like they weren’t cleaned before being coated. Junk. Quite a bit of dirt underneath the coating.

Return them and ask for replacements.

Poor quality control.

[Scharbag]

Vehicle specifics:
2011 E92 M3 6MT ZCP
31,430KM (27,400KM by PO and he admitted that he drove it hard)
Never winter driven and always warmed up before spirited driving
Dinan tune (8600RPM redline)
Never tracked
PO changed with TWS 10W60 every 5-8K KM

On a positive note, the inside of the engine looks like new!!





I will get in touch with BE and discuss the bearings. Worst case I have to buy shells for 2 pistons to make sure they are all good. In no rush as I live on Hoth and it will be months until the snow melts. UPDATE: BE sent me replacement shells. They rock!!

And for grins and giggles, here are the shells for all 8 pistons now:



Not great lighting, but there is a bit of wear. My buddy, who is a good mechanic, said "those are already on their way out" when I showed him. He showed me a high mileage Honda bearing and it has ZERO wear on it.

Some notes on my install:

SUBFRAME REMOVAL (the way I did it - assume subframe is already hanging)

1: evacuate power steering reservoir
2: disconnect all power steering hose clamps along subframe

ensure you get the nut that is close to the steering rack banjo bolts

3: undo banjo bolts (catch can is required - I zip tied the hoses out of the way and put a rubber glove over the open ends after I got a drip of PS fluid in the ear...)
4: remove 18mm head bolts from the front and rear control arms at the subframe

now the whole thing is hanging from just the tie rods

5: verify that there is nothing still attached and remove the 21mm tie-rod nuts
6: now the subframe can be removed which gives super awesome access to the oil pan and rod bearings

TRANSMISSION TO OIL PAN BOLTS

One of these is a real PITA to get out due to stuff in the way. A box end wrench will work fine. While the 10mm shown in the DIY fits and will work, I found that a 3/8" fits much better on the E12.

FACTORY ROD BOLTS

I used a 12mm 12 point 3/8" drive impact socket (Tekton) and it fit very well on the factory hardware. As others have said, I think high quality 12 point sockets work just fine.

Cheers,

[pbonsalb]

Some have over 30k on replacement bearings, but no one has gone back in yet to replace them again. Mine weren't terrible at 60k when I changed them so I figured I would change them again in another 60k. 3 years later I am at only 90k so it may be a few more years -- I drive 2 cars year round so it's taking me a while.