Aftermarket Rod Bearings Spun

Burble tunes 🙄🙄
great way to ignite the rear of your car

Assimilator1 wrote

I don't know how Manufacturers get away with doing it, you'd think that'd breach noise limits?

As usual, no OEM is insane enough to take it as far as the aftermarket does. OE burbles/pops/bangs are rarely much louder than the rest of the exhaust, and I don't think any other than Lamborghini will shoot flames stock.

Assimilator1 wrote

Coolant cocktail??

It's a great drink for these type of people

330indy wrote

Burble tunes 🙄🙄
great way to ignite the rear of your car

Mate . You nailed it ...

Scharbag wrote

There is that, but even good shops can make mistakes.

I would be so very surprised if a set of properly installed BE bearings spun. Look at SYT_Shadow and his main failure. Bearing #1 took a beating and did not spin.

Cheers,

What oil did you use?

Excers wrote

You're correct. Haven't done more then dropped the pan.

So 5 years have gone by since your B.E. bearing spun. I read the whole thread and am still wanting to know, "did a main bearing fail or not?"

Same!

Excers wrote

I will keep you updated.

Did you ever hear back from the buyer about your old engine?

I belatedly noticed this ad (after I'd PM'd him) by him for the old engine parts.
He states there and in the PM that the mains had indeed failed.

Excers wrote

Recently parted an S65 from my 2011 E92 M3. Spun bearings 1 and 5 at 81k miles due to oil starvation in journal one, had the main fail. All parts for sale. Let me know if you need anything.
Located in AZ
Willing to ship at buyers expense.

Available:
1 Coil pack
Heads
Oil pan
Connecting rods
ICV
Intake plenum
Throttle bodies
Pulleys/balancer
Injectors
Water pump
Wiring harness

Sold:
TA
Valve covers

Updated my previous message.

Assimilator1 wrote

Did you ever hear back from the buyer about your old engine?

I belatedly noticed this ad (after I'd PM'd him) by him for the old engine parts.
He states there and in the PM that the mains had indeed failed.

I wonder how many engines had failed main bearings after fitting the larger clearance rod bearings?

Sneaky Pete wrote

I wonder how many engines had failed main bearings after fitting the larger clearance rod bearings?

This raises a very intriguing hypothesis! I’m thinking it’s not a coincidence.

bigjae1976 wrote

That's very reasonable. One of the benefits of the BE bearings is you can use oil analysis.

I might have went the BE route but they're always sold out too. I went OEM WPC. First swap was 53k. I plan to swap them at 80k-85k out of curiosity.

You change them again? If so, how did they look?

charliev68 wrote

This raises a very intriguing hypothesis! I’m thinking it’s not a coincidence.

It really does not. The variable flow oil pump in the E92 maintains adequate pressure as shown by the data presented to the community.

Also, all of the oil that goes to the rod has to go through the mains.

Scharbag wrote

It really does not. The variable flow oil pump in the E92 maintains adequate pressure as shown by the data presented to the community.

That being from the same source that got the rod bearing clearance wrong?
Didn't BE measure and report a drop in oil pressure when running with extra clearance bearings?
Or have they since edited the original report to remove it.

Scharbag wrote

Also, all of the oil that goes to the rod has to go through the mains.

Dropping the pressure at the rod bearings will have an effect on the upstream pressure at the mains. Increasing the flow to offset the drop in pressure at the rod bearings carries its own problems.

Scharbag wrote

You change them again? If so, how did they look?

Have not. Forgot I made this empty promise. But I swear…I’m getting close. I’m at 107k now. Making arrangements to do this and bunch of stuff in Apr/May/Jun.

Sneaky Pete wrote

That being from the same source that got the rod bearing clearance wrong?
Didn't BE measure and report a drop in oil pressure when running with extra clearance bearings?
Or have they since edited the original report to remove it.


Dropping the pressure at the rod bearings will have an effect on the upstream pressure at the mains. Increasing the flow to offset the drop in pressure at the rod bearings carries its own problems.

BE had oil pressure and oil flow gauges connected (as I think you already know, you've read their full report about it right?), there's no doubting that data, unless you're saying they just made it up??
If not, their data shows (from memory) just a 3-4% drop in pressure.

The rod bearings are up stream of the mains, not the other way around (maybe you just typo'd?).
I don't see that increasing the flow (to compensate for faster oil loss at the rod bearings) would cause any problems, other than quicker removal of heat. What problems do you think it could cause?

Sneaky Pete wrote

I wonder how many engines had failed main bearings after fitting the larger clearance rod bearings?

Very few, literally just a few, which is far fewer than the engines that have failed with OEM rod bearings.

Assimilator1 wrote

BE had oil pressure and oil flow gauges connected (as I think you already know, you've read their full report about it right?), there's no doubting that data, unless you're saying they just made it up??

Because their other data has been so reliable in the past?
Didn't they just have a flow/pressure meter after the oil filter? Not exactly that much use in measuring oil pressure at the bearings themselves.

Assimilator1 wrote

The rod bearings are up stream of the mains, not the other way around (maybe you just typo'd?).
I don't see that increasing the flow (to compensate for faster oil loss at the rod bearings) would cause any problems, other than quicker removal of heat. What problems do you think it could cause?

One of the oil feeds goes to the mains and rod bearings...the oil will tend to take the route with least resistance..as you increase the RB clearance it becomes easier for the oil to escape to the sides which will increase flow through the rod bearings at the expense of flow through the main bearings.

Anyway lost interest in this story now...I can see that folk still want to believe the too tight RB clearance even now.
So I'll leave you all to carry on...much to the relief of some people no doubt.

Sreten from M539 Restorations mentioned during his S65 rebuild that the timing chain pulls up on the crank and consequently causes more wear on that main bearing and the wear decreases are you move down the line.

He pulled the mains on a S65 and you could see a reduction in wear moving from front to back.

F32Fleet wrote

Sreten from M539 Restorations mentioned during his S65 rebuild that the timing chain pulls up on the crank and consequently causes more wear on that main bearing and the wear decreases are you move down the line.

He pulled the mains on a S65 and you could see a reduction in wear moving from front to back.

M539 is far from the only source who suggest just that.

Btw bumped into another main fail here, VAC non extended RBs in this case (who later upgraded donor engine with VAC again).

Sneaky Pete wrote

Because their other data has been so reliable in the past?
Didn't they just have a flow/pressure meter after the oil filter? Not exactly that much use in measuring oil pressure at the bearings themselves.

One of the oil feeds goes to the mains and rod bearings...the oil will tend to take the route with least resistance..as you increase the RB clearance it becomes easier for the oil to escape to the sides which will increase flow through the rod bearings at the expense of flow through the main bearings.

Anyway lost interest in this story now...I can see that folk still want to believe the too tight RB clearance even now.
So I'll leave you all to carry on...much to the relief of some people no doubt.

Re flow meter, possibly, I recall that it couldn't go anywhere else.
I can't see anyone being able to measure pressure at the main bearings, maybe BMW if they tapped into the oil feed to a mains??
Whatever the oil pressure is in the main oil gallery will be what it is at the mains oil feed (near enough).
I'm pretty sure that their are individual oil feeds for each main bearing (same with pretty much any modern-ish engine AFAIK), each main bearing then goes onto feed a pair of rod bearings.
So their would not be less flow to the mains as the rod bearings are in series to the mains (and after), not parallel.
If the oil pump couldn't keep up with the increased flow at the rod bearings, then yes pressure would drop at the mains (& throughout the system). But that isn't the case with BE v1, bar a few %.

Btw, FWIW, I think the case for too tight clearances has been weakened, but not written off yet. Bearing in mind that Mahle MS bearings have increased clearance anyway.
But the corrosion damage to bearings definitely warrants more thought and investigation (something that could be done with oil analysis).

Wouldn’t the WPC process slightly increase bearing clearance?

Yea AFAIK it does, but by a miniscule amount, IIRC 2-3 microns.