E46 / E92 M3 advice

True, but you don't see the same number of dodgy bearings pulled from other high revving cars either, the only one I looked into was the Honda S2000 (9k RPM, 100bhp/ltr) just a handful as I recall. Apparently it's super rare for the Audi V10 unit too though.
Anyway, big end bearings are not meant to be a contact part when running (just starting and shutting off), so should be lasting much longer.
 
Surely part of the design causing an issue with the longevity of a component when it is used as intended, is the definition of a design flaw?

Obviously its entirely up to you but I'd definitely consider doing them soon because you never know. They might be totally fine, but they might not be. It would play on my mind. :p

Yeah I'm gonna replaced the whole engine too just in case.

This is the point i made earlier, many people have replaced them and they were still ok. (I don't have time to trawl through months of facebook posts). I know enough about engines and oil to argue it is not a flaw and I'm happy to 'risk' my engine.

Its certainly not a must have whenever the car changes ownership like being claimed here
 
True, but you don't see the same number of dodgy bearings pulled from other high revving cars either, the only one I looked into was the Honda S2000 (9k RPM, 100bhp/ltr) just a handful as I recall. Apparently it's super rare for the Audi V10 unit too though.
Anyway, big end bearings are not meant to be a contact part when running (just starting and shutting off), so should be lasting much longer.
Thats because people aren;t pulling bearings out of engines 'just in case'. This issue is self perpetuating.
 
Yeah I'm gonna replaced the whole engine too just in case.

Now you're just being daft, you know thats not the same.

I know enough about engines and oil to argue it is not a flaw

Rod bearings that lunch themselves before most engines have even lost their honing marks, because the tolerances are so tight that they aren't lubricated sufficiently and make direct contact with the crankshaft... That is most definitely a flaw.

Thousands of people have had issues, there are specialists and experts all over the world who deal with the issue regularly.

But you are right because your M3 doesn't have rod knock and you've seen a couple of examples where they looked fine when removed?
 
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Who’s the expert ? BMW engineers or some guy who sorts bearings in his lounge and sells them as the fix ?
 
Who’s the expert ? BMW engineers or some guy who sorts bearings in his lounge and sells them as the fix ?

By that logic, no car ever made has any design flaws because who knows better, XYZ engineers, or some mechanic? That isn't how it works, and that isn't a valid argument.

I give up. :p
 
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What exactly are you giving up on.

Do you have a incentive to try and convince me I needed to change my bearings 4 years ago otherwise it would fail?

people have different levels of risk/anxiety. It’s up to then of them want the insurance to know they are nice new bearings and that makes sense. But don’t make out people are stupid for not doing them straight away when you buy one
 
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No I'm not trying to do that at all, I was arguing that it is a flaw in the design. You are free to do or not do whatever you like! :)

You bought yours on very low miles, I assume possibly a one owner car, and you made a judgement that they had looked after it correctly, and presumably you have continued that level of care.

Though you yourself said at least that it can be an issue if the cars have been driven hard from cold a lot, when buying a now 10+ year old M3, you aren't going to know if it has been driven hard from cold, and the seller certainly isn't going to tell you.

Hence me saying that if there is no history of it being done, I would want to have it done.
 
These threads always end up like this.

Talking about an E92 M3, buys an E46 330Ci
Talking about a Caterham, buys a Suzuki Swift
Talking about a hot hatch, buys a diesel Corsa.

Every time! :p
 
I'm on the fence as the weather it's a real problem or an 'interner' flaw (I say this having an e92 me myself). I believe the oil is too thick, however I don't believe there is an oil that is the same cold as it is hot compared to what the e92 uses as I think it's 10/60. Maybe 5/50 would have been a better choice? What I can't fathom is that if the surfaces do touch, surely at some point they will have worn enough to not touch, you know if the file something down it won't catch? Maybe some have slightly wobbly crank shafts and it just catches:confused:.
 
What exactly are you giving up on.

Do you have a incentive to try and convince me I needed to change my bearings 4 years ago otherwise it would fail?

people have different levels of risk/anxiety. It’s up to then of them want the insurance to know they are nice new bearings and that makes sense. But don’t make out people are stupid for not doing them straight away when you buy one

can you imagine anyone would change their bearings and say, “that was pointless, wish I hadn’t bothered” :D

Literally everyone will on the page of being glad they did it almost as effort justification. Like the people recommending Millers Oil... “never had any issues” as though it’s some sort of industry recognised accolade if your engine doesn’t go snap, crackle and pop.
 
These threads always end up like this.

Talking about an E92 M3, buys an E46 330Ci
Talking about a Caterham, buys a Suzuki Swift
Talking about a hot hatch, buys a diesel Corsa.

Every time! :p

Fortunatley it’s a mixture of owners rather than a list of your last 12months of consumption.
 
These threads always end up like this.

Talking about an E92 M3, buys an E46 330Ci
Talking about a Caterham, buys a Suzuki Swift
Talking about a hot hatch, buys a diesel Corsa.

Every time! :p

So what you're saying is you want a Suzuki Swift? :p

Good E46 M3's aren't easy to find without paying inflated prices, I'm not desperate but always have an eye out.
 
Hey! The Swift's are a good little car, I know as I work at a Suzuki dealer :p;)

theone8181
The trouble is the wear removes all or part of the protective soft (babbitt) layer of the shell, this then leaves the bearing vulnerable to scoring and galling when dirt particles get in there, or when the engine is started or stopped. Additionally the wear isn't even, so the shape of the 'hole' is no longer right and this negatively affects the hydrodynamic oil film that's meant to keep bearings and crank apart (not something you want to risk on an 8000+ RPM engine costing ~£7-8k + labour for a 2nd hand engine). You can read about bearings in the pdfs I linked in my massive post on the previous page (at the end of it).
You could argue that a very slight wearing wouldn't cause a problem for a very long time, but the trouble is you don't know which engines will be ok until you either strip it or it dies!

That's because people aren't pulling bearings out of engines 'just in case'. This issue is self perpetuating.

Who’s the expert ? BMW engineers or some guy who sorts bearings in his lounge and sells them as the fix ?
You're still missing the point that most shells removed are excessively worn, and all this started because an initially small number of engines were blowing up with no obvious reason about 7-9yrs ago or so, the more people looked the more people found there was a problem (with most engines, but not all).

If you are referring to BE bearings as being 'some guy who sorts bearings in his lounge' then you are massively mistaken, they are a company who rebuild all sorts of engines and have done for many years, and at least part of their workshop is more like a machining shop, they have an extensive array of tools to carry out very high precision measurements of various engine parts. If you weren't talking about BE then ignore that line ;).

Robbo
A very nice car you've bought :cool:

Jonnycoupe
Not sure what you were getting at with that post, but anyone who has it done will be glad it's done as they now know they don't have dodgy/overtight* bearings regardless of how good or bad their old bearings came out.
*assuming they don't use OEM bearings, lol.
 
Most people go for OEM bearings though. As they are the right clearance for the engine.

The car sounds epic when cold and people like to make nice noises
 
On the rod bearing issue, my thoughts are that this is a car that was specced with tight tolerances, thick oil and a high rev limit - it's a recipe for disaster in the hands of the wrong owner. If you bought the car from day one, and you were aware of this and treated the car accordingly, then I don't think you would have an issue at all.

Unfortunately, in the real world, 95% of the people who bought them from new had a bulletproof warranty and a 36 month PCP finance package on them so they will have cared little about what state the engine may be 5-10 years later. Also, as it's a nice sounding V8, every **** who has sat in it is likely to have revved the **** out of it to show their mates, whether that be the owner, the mechanic they take it to, the MOT tester, the trader who they bought it from etc. With this in mind, it's little surprise why these cars have earnt a reputation for throwing their RB's.

I used to own an E92 M3 and i put my money where my mouth was and paid the £1300 to have them replaced with BE Bearings, not because I thought that they were any "better", but because I was steered that way by the well known specialist. Had they been replaced with OEM parts, I am confident they would have been fine for the lifetime of the car because I was aware of how critical it is to warm them up prior to revving them, which I am certain would have prevented any further issues. Either way, my decision to have them done when I did saved me £8000 as my bearings were very worn indeed and the engine was close to nuking itself.

Personally, if I was ever to have an E92 M3 again, I wouldn't buy one without the RBings being changed. There is too much at stake to not have them done and take that risk at the mileages, ages and number of owners they've been through - I can afford the £1300 to have them changed, but I can't afford to pay out £8000 for an engine rebuild if the engine goes.
 
And I think this is sensible. How did they look when they came out

I did look on the dedicated bearing Facebook group again last night ( I have been interested in this subject for several years) and there’s still the doubt about the mains. If the rods are indeed tight then the mains are too but these get ignored. Several have since failed due to mains (bigger rod clearance and centripetal forces mean they can be starved enough to mean the oil film breaks down. A journey bearing create its own pressure, the pump simply provides the oil) also a few have suffered from assemble issues causing a later engine failure.

It’s certainly random the nature of the issue hence I don’t believe a design flaw.

Reality is that if I don’t change them then the car will be harder to sell. £1400 at least gets new engine mounts. Which are made from chocolate it seems
 
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