[UnnecessarilyComplex]

Hi guys, I always liked to make a memorable entrance and I hope to do so here!
I know it's pretty rare for low mileage M57 engines to give up the ghost but as the title says, mine almost certainly has.

2011 titanium silver, sport package, hifi audio, cic, black leather and walnut interior w/ fixed back seat. I've owned it for one day short of two years, bought it from the first owner bone stock (not even tint) and immaculate service records with 64k on the clock.

At 70k miles I did all new silicone vacuum hoses, new solenoids/ pressure converters. CBU clean, new gaskets for VC, vacuum pump, intake manifold etc. Intercooler upgrade, Forge boost pipe, ATM charge pipe upgrade and new o rings throughout air tract. CCB reroute and oil catch can. Full emissions delete including removal of all tanks, pumps etc. Race pipe, egr block off at exh manifold, downpipe and full exhaust. Trans service, mechatronic seals etc. Rear diff fluid change. New thermostat and coolant flush. XHP trans tune, DME tuning by R. Needham.

Snow Performance MPG Max stage 3 water/methanol injection with 175ml and 325ml nozzles located in charge pipe. EGT probe tapped into pre-turbo exhaust back pressure banjo bolt. Two stage solenoids mounted on custom race pipe bracket. IAT sensor relocated to intake manifold just forward of map sensor. Controller mounted in place of driver side air vent, 7 gal trunk mounted tank, pump mounted in location previously occupied by DEF pump under factory amp. 50/50 water meth ratio.

Daily driver for 100 mi commute, 90% highway. Oil and fuel filters changed religiously every 3-5k with Mahle filters and T6 15W/40. Air and trans filter/fluid changed every 15k. Optilube XPD every fill up. Michelin PS4 tires on 18" 195 wheels, 20% tread left on my second set of rears, first set of fronts still at 90%

A/C belt failed around 72k and again 90k.

Cylinder 2 injector failed at 85k, brand new oem replacement. Went ahead and replaced HPFP with new oem R70 and fuel control actuator (bought a used R90 too but still sitting in my shop after seal replacement). All was well again after these repairs until the rod knock at 109k.

Side note: my old FCA was bad but never triggered a specific code for it, just general rail pressure plausibilities. I found that when I ran the fuel bleed procedure on my Foxwell scantool the rpm would remain at idle speed throughout the entire procedure with the faulty FCA, after FCA replacement the rpm would increase during procedure. The faulty FCA tested good electrically but the metering rod was mechanically jammed/ frozen (no water or rust present). I have browsed the forums quite a bit and haven't come across anyone describing this behavior, thought it might be useful to someone..

Okay, back to the present! On my way home several days ago about 20 mi into my commute I was putting along in heavy traffic light throttle up to 85mph back down to 60, up down, up down (SW Florida traffic) when I started hearing a light tapping. I turned off the A/C thinking it was the belt again then put it in neutral and gave a light throttle blip and the tapping became a knocking chorus matched in tempo to rpm. Not my first rodeo, pulled over shut it down and called roadside. Meth system was off, the engine never got hot, no oil pressure warning, oil level right at full. Reduced power operation lit up on my way to the berm. Scanned for faults and found a code for smooth running cylinder 2 (the only code present).

Got it unloaded at my shop for inspection, the engine turned over freely and started with no noticeable hesitation but with a very pronounced knock (seemingly louder without the rush of traffic blasting by) and noticeable blowby from the open oil fill. Small puffs of white smoke emitted from both exhaust tips and despite the situation I had to smile slightly, glad that I opted to purchase an exhaust with good symmetry. I Shut it down quickly and went on to inspect the oil filter (experiencing renewed love for bmw not using canisters) and was not dismayed in the slightest by what I found because it was exactly as I expected. Sparkly ferrous man glitter shiny and spotted across the inky black pleats of the 2k mi old filter element. I haven't dug in further but I'm pretty confident of my early diagnosis. I am an experienced diesel mechanic (marine engineer) and have seen many times what it looks like inside an engine that's singing that unmistakable sorrowful song of a bad cylinder/rod bearing failure.

Thanks for reading along this clusterf*** of a tale. I am deeply grateful for the resources of knowledge provided here, it has been a great help to me many many times! I will do my very best to post the resolution to any problems I present to the forum and also to provide insight to others only when my knowledge and experience are applicable (I'll try not to talk out of my a**)!

[wcs531]

This really sucks, as you are doing shorter fluid intervals than 99% of people out there. It sounds like it has to just be a faulty/out of spec rod bearing as you said the previous owner also had meticulous service records.

Would you be getting blowby if it was the rod bearings though? I guess bad rod bearings could quickly lead to more damage elsewhere.

[UnnecessarilyComplex]

I think cyl 2 was compromised at 85k mi when the injector failed. If it got stuck open it could have washed the walls and caused the rings to partially seize and damage the rod bearing. My guess is that it just took time to become a catastrophic failure. Just guessing though. This is my first M57, but I've been working on marine diesels for years and the same physics and principles apply.

[Yozh]

Did I read this correctly in your original post that you use T6 15w40. Cos if so, there is your problem.

[UnnecessarilyComplex]

You read correctly, to be more specific, I've been running 15w40 in the summer and 10w30 for our few short months of winter. I spend 90% of my 100mi daily commute between 2700-3100rpm with ambient temps frequently in the mid 90's and above. I ran the heavier oil to compensate for this abuse and have only recently learned of the excessively tight tolerances of the m57.

[UnnecessarilyComplex]

Yozh, if you have any personal experience would you mind elaborating a little more about the oil weight being the most likely cause for failure please? I have loosely followed the forums for the past couple years and performed some specific searches more recently and just can't seem to find many cases of engine failure. Even fewer still are threads that detail the specific cause and the full extent of damage. Thanks for joining in on this btw, I know your input to be valuable and respected on this forum!

[Tambohamilton]

Bummer. Sorry to hear about this...

Agree that if there's blowby/white exhaust along with man-glitter in the filter, you've got a problem with bore(s)/rings.

Good luck with the fix!

[UnnecessarilyComplex]

Thanks Tambo. It might take awhile for me to get around to it but I'll be sure to mic all the bearing surfaces, bores, etc and send an oil sample off to Blackstone and post the findings here.

[UnnecessarilyComplex]

I bought an eBay engine today. Clean florida car, 90k w/manifolds, turbos and injection pump included. Not crazy about the miles but the lower mileage ones are all from up north and the ones that are out of the cars look like hell from the road salt.

If my head is undamaged I'm going to swap it onto the eBay motor so I don't have to deal with the CBU right away. I had my valve cover off recently and my head is still pristine from the meth injection. Also going to pull the oil pan and inspect the bearings, clean up the sludge.

Wish me luck on not receiving a boat anchor.. If you guys think of anything else I should be doing please do chime in!

[RL18]

Originally Posted by Yozh

Did I read this correctly in your original post that you use T6 15w40. Cos if so, there is your problem.

Edit: I think Yozh is point out the oil weight. Didn't catch that at first. Cause I use 5w40 rotella t6 not 15w40

[UnnecessarilyComplex]

Gotcha, and I stand corrected! I do in fact use t6 5w-40 as well. I have been using nothing but 15w-40 for so long at work and gone through so many thousands of gallons of it that I automatically say (and type, apparently) "15w-" whenever I reference any 40 weight oil. Sorry for the confusion.

[apexit4]

Out of curiosity, whats the reasoning behind a 15w oil potentially causing such an issue?

My best guess would be that the oil is too thick before start up to provide proper lubrication. That would also mean that most of the damage would be inflicted before reaching normal operating temps.

UnnecessarilyComplex You asked about other items to tackle while the engine is out. Aside from the obvious items like upgraded silicon lines, water pump, thermostat, new seals/o-rings, I would suggest replacing the rod bearings and motor mounts. If you ever plan on doing the in the future you'll have to drop the subframe anyway, so now would be a convenient time to replace them. And if you plan on doing a DPF delete, doing one now would be convenient as well since the passenger side motor mount has to be removed if doing the procedure with the engine in the car.

[RL18]

Originally Posted by apexit4

Out of curiosity, whats the reasoning behind a 15w oil potentially causing such an issue?

My best guess would be that the oil is too thick before start up to provide proper lubrication. That would also mean that most of the damage would be inflicted before reaching normal operating temps.

I would say it depends on climate. I couldn't ever get away with a 15w40 in Maine, cold starts would be really rough until reaching operating temps which I probably don't get up to temp in my deleted 335d for maybe 15mins into my drive maybe longer. My x5d with emissions is quicker but I would never run any oil but the bmw oil in that. Also it just makes sense to get 5w40 over 15w40 because they will be the same at operating temp but the 5w40 would be thinner at lower temps providing better protection on cold starts.

[UnnecessarilyComplex]

I'm not sure about the definite reasoning behind Yozh's statement but I believe you guessed correctly. I was just told by an experienced tuner that the m57 internal tolerances are excessively tight "possibly to a detriment". The cause of failure is yet to be determined but I am betting that the piston/rings in cyl 2 caused rod bearing failure in that hole. I haven't ruled out oil weight as a possibility and I stated earlier, I will be posting info and photos of the full extent of the damage once the car is up and running again.

I appreciate the suggestions, most of them have already been taken care of. Motor mounts are pretty much the only thing you mentioned that I haven't done yet mostly because I haven't decided on whether I want to stick with vacuum or switch to solid mounts and mine are still in good shape. Im going to inspect the bearings in the used motor but won't be replacing them unless they are compromised. At 90k, assuming they aren't called, they should have plenty of life left. Instead, I'll be putting my old motor back together with all new parts and a hybrid setup and swapping engines again once complete.

[RL18]

Originally Posted by UnnecessarilyComplex

I'm not sure about the definite reasoning behind Yozh's statement but I believe you guessed correctly. I was just told by an experienced tuner that the m57 internal tolerances are excessively tight "possibly to a detriment". The cause of failure is yet to be determined but I am betting that the piston/rings in cyl 2 caused rod bearing failure in that hole. I haven't ruled out oil weight as a possibility and I stated earlier, I will be posting info and photos of the full extent of the damage once the car is up and running again.

I appreciate the suggestions, most of them have already been taken care of. Motor mounts are pretty much the only thing you mentioned that I haven't done yet mostly because I haven't decided on whether I want to stick with vacuum or switch to solid mounts and mine are still in good shape. Im going to inspect the bearings in the used motor but won't be replacing them unless they are compromised. At 90k, assuming they aren't called, they should have plenty of life left. Instead, I'll be putting my old motor back together with all new parts and a hybrid setup and swapping engines again once complete.

I think you have everything covered pretty well. I do recommend that you keep the stock engine mounts. A solid mount would probably transfer a lot of vibration through the chassis. But, maybe you could be the first cause I don't know of anyone who's tried it to prove it

Goodluck on the rebuild though! I saw you said you will be going with BRR for tuning so you'll be in good hands

[335dlci]

Yeah don't switch mounts.

[UnnecessarilyComplex]

I don't mind a little extra vibration at idle, this car is just a commuter for me and spends very little time idling. I saw a few videos of guys using glaziers urethane to stiffen up the 335i mounts, pretty sure I'm going to try this eventually. If it doesn't work out I'll go back to stock.

[UnnecessarilyComplex]

Update:

Holy cluster***, this thing is almost as bad as pulling the engine from a 3.0 A4! What a mess...

[Tambohamilton]

I dented my partners 118d bonnet/hood when I removed the engine...from the inside!

Enjoy disconnecting the everything

[335dlci]

Very easy to pull these engines the way they go in.

[UnnecessarilyComplex]

I'm sure that pulling the block will be easy, it's the clearing away of all plumbing and wiring that's a PITA. It took me the better part of an hour just to drain drain the coolant and remove the hard lines without breaking any of them. Progress is slow. I work meticulously and organized with a constant eye for cleanliness. I also have two young daughters I'm alone with in the evenings that keep my neck on a swivel when I have them in my workshop.

[Tambohamilton]

Hahaha, kids slow down progress more than a little!