[slipstreampilot]

Perhaps you should read before you snap at someone and opine. I have more than just anecdotes - I have personal, real-world experience and referenced the work of a brilliant mechanic who has worked on these engines since they were introduced.

The information comes from my personal friend and mechanic in Atlanta who specializes in diesels and works on M57 powered cars several times a week - maintenance and repair. Whether for the street, track or his own two vehicles. In fact he just finished replacing an engine on a X5 35d this week due to a FOD related engine failure. Destroyed piston/cylinder #2.

My 2nd 335d just had a Wagner intercooler installed and a custom tune completed by him. This guy’s work is well worth the 3 hour drive and he knows the M57 likely better than anyone else in the U.S.

My personal experiences (not regurgitating anything) with smoke at startup on more than one of my 3 M57 powered vehicles was 100% solved with swapping out the offending turbo. Those are facts, not hypothetical nonsense by some keyboard warrior who read a post or article somewhere.

In fact - here’s his words:
“I have not seen one car to date where the primary cause of burning oil was valve stem seals - even on M57s with over 250k miles. They do leak down a little oil if the car sits for long periods without being run, which will cause smoke at startup - as it would for any car that sits for several days, weeks or more. That’s any engine. That doesn’t really happen on a daily driven M57, and I haven’t had to rebuild or recondition a head to date for leaking valve stem seals. Roughly 60% of oil consumption issues are the small turbo, 20% were the big turbo and the rest were maintenance/neglect/mechanical failures and the engines were junk and not worth rebuilding.”

He currently has 9 small turbos in stock, albeit 2 are hybrids. 7 OEM small turbos on the shelf, and he installs one every few weeks on average. Much lower frequency on the big turbo. He has 2 in stock. He has one set of valve guide seals in a dust covered box, just in case.

I hope that clears it up for you.

[lnxguy]

You have personal real world experience paying for someone else to work on your car? Have you ever pulled a head on one of these engines? I have (Due to a bad headgasket) and you wanna know how many of the valve stem seals were leaking? 4 of them.

I also have multiple 'mechanic' buddies who make a living on these cars and valve steam seals leak all the time. It's nothing crazy which is why unless you're pulling the head you wouldn't bother to replace them. They aren't a source of major oil consumption (unlike bad VCGs, CCV issues or turbos).

But to sit here and deny that actually happens makes me think you aren't as educated or in the 'know' as you think you are or your brilliant mechanic isn't so brilliant.

[slipstreampilot]

Says the keyboard warrior who likely couldn’t identify the oil dipstick on an M57. How many of these vehicles do you own? How long have you owned one? Have you actually turned a wrench on one? Has a single person paid you to work on their M57 powered car?

I actually do a lot of work on my own cars - 3 M57 powered vehicles. I have trouble shot many of my issues, to include simple things like dropping the exhaust at the downpipe to identify the obvious source of oil, or pulling intercooler hoses to check for excessive oil (there is always some oil in them). Leaking valve stems don’t lead to oil in the exhaust or the intercooler path for that matter. 100% from the turbo(s). But you’re the smart guy insulting others.

Yes - my personal experience. 3 turbos to date on 2 of my vehicles. I was the second owner of all of my vehicles - and it was clear the original owners didn’t bother to idle down prior to shut down and likely never got everything up to temp on short trips creating excessive carbon. Turbo(s) was (were) 100% the cause in all of my oil consumption cases.

Excessive oil burn and smoke at startup completely solved with turbo R&R. Pretty simple, but the logic of it has left you befuddled and resorting to insults because you propped yourself up as the great sage of the M57. Not one valve stem seal replaced - just the turbo and the problem was solved. I don’t know what’s so hard to understand, but here we are.

Oh - and when the offending turbo was examined and disassembled - the center bearing piston seals on the turbine side were shot. Again, my first 335d has almost 150k miles, 120k are my miles - hard driven miles - tuned to over 700 lb ft of torque at the wheels at about 65k. Stock fuel, injectors, turbos and the big turbo started pissing oil around 75k. Replaced it with a minty used turbo which had approximately 45k on it - and wallah! It stopped burning oil. The original owner was an old lady who made short trips with it. Carbon loading in the oil lead to the turbo’s turbine oil seal leaking like a sieve. The small turbo is now starting to weep a small amount of oil and will be changed out when I get tired of the consumption. That small turbo as lasted much longer than expected.

Not even a tiny bit of concern or consideration related to the valve stem seals. How do I know? A small amount of oil present in the downpipe when examined cold. If the downpipe was dry - then I might think valve stem seals. There’s the right amount of oil in the exhaust and turbine housing to cause smoke at startup. Oil consumption has ticked up as well. Intake manifold and valve cover gaskets are relatively new as well - with no signs of leakage.

The last thing… I am interested in knowing what exactly are your qualifications related to this subject? Where is your expertise derived? You seem keen to insult other’s intelligence when they present facts counter to your faceless supposition, despite the fact I supported my position with facts and actual 1st person experience. Again - who pays you to work on their M57 powered cars? Yet you insult likely the most experienced and talented euro diesel mechanic in the entire Eastern U.S., possibly the whole country. Why? Because he didn’t agree with the ‘great keyboard sage’ on this site. I think I’ll stick with my guy - I know for a fact he knows what he’s doing and that he knows what he’s talking about. You? Everything you have stated so far is counter to what I know to be factual and true. But feel free to dig in.

[Tambohamilton]

I think we can all agree: BMWs leak oil. Shocker.

[ptpending]

Originally Posted by Tambohamilton

I think we can all agree: BMWs leak oil. Shocker.

i disagree
properly maintained bmw do not eat oil these days
also the oil should be synthetic like bmw sticker usually requires, w40 is more often will be synthetic then w30
valve stem oil problem is for high temp (105C) cars like N57, N52, N53 N54 N55
M57 and M47 barely reach such temp
so their issue usualy turbos wear, incorrect(earlier versions had foam breather which did better oil separation job but quickly clogged, last vertex version does opposite) or clogged breather
the non functionin breather create condition when oil began to leak thru all weak gaskets in engine
some bmw recomendations like 5w30 oil and 20-30k kms oil change interval are designed to have additional engine repairs
not working thermostat and glow plugs lead to non-availability of the dpf regen cycle and clogged dpf and lose of the power