Engine Failure @ 14k miles

[tdott]

Originally Posted by former 240 s14

Given the main bearings be new and having 14k miles on them the probabily they were the culprit is small IMO.

Oil debris still in the oil system from a previous failure and that probability goes up drastically....

[former 240 s14]

Originally Posted by tdott

Oil debris still in the oil system from a previous failure and that probability goes up drastically....

Agreed. 100%. As I was not the owner of the vehicle at that time I can say with absolute confidence the system was flushed correctly. We will know here pretty soon once Ben & Team get the bedplate off and mains inpsected.

Regardless I do plan on having extra clearance on main cap 1's top bearing. That should help moving forward.

Rubin

[former 240 s14]

New (to me) oil pan is back from AAF. They did a great job, pics stink but it was near impossible to get inside the sump. They did the BW Dipstick Kit while there were there too.

Rubin

[DrFerry]

Originally Posted by former 240 s14

New (to me) oil pan is back from AAF. They did a great job, pics stink but it was near impossible to get inside the sump. They did the BW Dipstick Kit while there were there too. Rubin

It looks great. I hope it works well for you. Slowly and surely wins the race... PS: You posted with a 9:11 time stamp. I hope it's not an omen...

[former 240 s14]

Well today was a buzzkill. Engine showed up at Rogue headquarters yesterday and today they took the bedplate off to see the mains. We found the full culprit of the failure, Main Cap 1 bearing failure. It only partially spun then blocked the oil feed to the crank causing the over heating issues to cylinders `1 & 5. The main journal cracked so the block is toast. Anyone want a paperweight?

Note these main bearings had 14k miles on them. Disappointing.

Found a new block that is just minutes from Rogue, so Ben can go put eyes on the unit before paying for it to ensure it's good.

Onwards and upwards.......... let's hope this is the last surprise I get on this rebuild.

Rubin

[omgzirra_exe]

although not good for power... time for some HX main bearings

[former 240 s14]

Originally Posted by omgzirra_exe

although not good for power... time for some HX main bearings

Thanks for the reco but Ben and I are aligned on doing ACL Race Series Main bearings with extra clearance.

Hadn't heard of HX before......are you running them?

Rubin

[pirategenes]

Originally Posted by former 240 s14

Well today was a buzzkill. Engine showed up at Rogue headquarters yesterday and today they took the bedplate off to see the mains. We found the full culprit of the failure, Main Cap 1 bearing failure. It only partially spun then blocked the oil feed to the crank causing the over heating issues to cylinders `1 & 5. The main journal cracked so the block is toast. Anyone want a paperweight?

Note these main bearings had 14k miles on them. Disappointing.

Found a new block that is just minutes from Rogue, so Ben can go put eyes on the unit before paying for it to ensure it's good.

Onwards and upwards.......... let's hope this is the last surprise I get on this rebuild.

Rubin

Oof - this is just brutal to see. But, at least there's a pretty clear explanation for what happened on track. And from this result, it seems to clear the stock oiling system as the culprit, which is good news.

Such a bummer this happened, but thanks again for sharing your experience, and it's wonderful to see you rebuilding even stronger. Nice work.

[former 240 s14]

Originally Posted by pirategenes

Such a bummer this happened, but thanks again for sharing your experience, and it's wonderful to see you rebuilding even stronger. Nice work.

Thanks. Always tell my students (I am an instructor for HPDE) that if they aren't willing to light several hundred dollar bills on fire then don't go on the track, bad things happen all the time.

It's not what I wanted obviously but this experience is reminding me how lucky I am to have some serious knowledge and expertise behind me supporting this stupid passion. Having a 4.1L shortblock from Rogue is going to make me giddier than Santa the day after Christmas, lol.

More to come next week when we find out if we have our block replacement or not.

Rubin

[omgzirra_exe]

Originally Posted by former 240 s14

Thanks for the reco but Ben and I are aligned on doing ACL Race Series Main bearings with extra clearance.

Hadn't heard of HX before......are you running them?

Rubin

HX is just a term for extra clearance

[former 240 s14]

Originally Posted by omgzirra_exe

HX is just a term for extra clearance

Gotttt it!

Replacement block is already picked up and at Rogue HQ. No time lost and found a fair deal on a good block. Two replacement rods in route as well.

Rubin

[F4rmost]

Originally Posted by former 240 s14

Gotttt it!

Replacement block is already picked up and at Rogue HQ. No time lost and found a fair deal on a good block. Two replacement rods in route as well.

Rubin

Great news on the new block and it looks like the baffling was welded in very well.

Are you still planning on running the accusump?

[former 240 s14]

Originally Posted by F4rmost

Great news on the new block and it looks like the baffling was welded in very well.

Are you still planning on running the accusump?

Welp update, the replacement block was not good, cylinder wall damage that wouldn't smooth out during machining, but we have a lead on another one from the same place so, fingers crossed.

I do still want to run an accusump. The system in general makes alot of sense, I just need to figure out the whole kit first and which ones I need. I'll probably get the car up and running/driving first then focus on that.

Rubin

[jmeenach]

Did you get the updated block yet?

[tdott]

Originally Posted by former 240 s14

We found the full culprit of the failure, Main Cap 1 bearing failure. It only partially spun then blocked the oil feed to the crank causing the over heating issues to cylinders `1 & 5. The main journal cracked so the block is toast.

The million dollar question would be, what caused the new oem main bearings to fail after only 14k miles since the rebuild?

I am not convinced the failure would be due to oil starvation. I think it's much more likely the rebuild was done poorly, there is a specific procedure to select the correct main bearings to use when doing the rebuild.



I know you said the PO did the rebuild, but it would be good to know what shop did it, and perhaps even reach out to do them to ask if they selected the correct main bearings based on BMW documentation, or did they just throw random main bearings in there.

IMO, after the first main bearing failure, it is still possible that the oil cooler, lines (or any other parts from the failed engine, vanos, oil pump, etc) were re-used and not cleaned / rebuilt properly which contain debris from the previous failure.

[former 240 s14]

Originally Posted by jmeenach

Did you get the updated block yet?

First replacement block ended up being another paperweight. Luckily we found a good core last Friday.

Now we just are waiting on the pistons to show up (oversized Mahle Motorsports 92.5MM 12.3:1 forged) and the torque plate (for machining).

Hoping they show up this week if we are lucky. We ordered the pistons over a month ago.

Rubin

[former 240 s14]

Originally Posted by tdott

The million dollar question would be, what caused the new oem main bearings to fail after only 14k miles since the rebuild?

I am not convinced the failure would be due to oil starvation. I think it's much more likely the rebuild was done poorly, there is a specific procedure to select the correct main bearings to use when doing the rebuild.



I know you said the PO did the rebuild, but it would be good to know what shop did it, and perhaps even reach out to do them to ask if they selected the correct main bearings based on BMW documentation, or did they just throw random main bearings in there.

IMO, after the first main bearing failure, it is still possible that the oil cooler, lines (or any other parts from the failed engine, vanos, oil pump, etc) were re-used and not cleaned / rebuilt properly which contain debris from the previous failure.

I agree with your assessment but would argue the failure was a multitude of factors including.........

1. Poor rebuild from previous shop - many inconsistencies were found during disassembly that could cause premature failure
2. Oil starvation - Road America is very difficult on engines. The carousel causes very high loads on the oil pan and mine was not baffled.
3. Oil temperature - although it wasn't hot for our engines I think the oil temps didn't help.

I am attacking each of the above issues and doing everything I can to ensure it doesn't happen again. The old shop (which I am still not comfortable naming) will never see this engine or chassis again. They had a good reputation in the Kansas City area but holes in that reputation are beginning to show, in my opinion.

Rubin

[omgzirra_exe]

Originally Posted by former 240 s14

Now we just are waiting on the pistons to show up (oversized Mahle Motorsports 92.5MM 12.3:1 forged) and the torque plate (for machining).

good job on getting the torque plate, not using one can easily ruin an engine build.

12.3 compression is going to be fun, luckily you get 93oct lol, I should've done 12.5:1 considering i only run E85 in my car and not 91oct.

[former 240 s14]

Originally Posted by omgzirra_exe

good job on getting the torque plate, not using one can easily ruin an engine build.

12.3 compression is going to be fun, luckily you get 93oct lol, I should've done 12.5:1 considering i only run E85 in my car and not 91oct.

Very true, having a tune that could run on 93 was an absolute must for me. This car is meant to be fun and quick, not time trial fast.

I am excited to see how the power will look going to 4.1 and higher compression in the mid-range. I am going to lower the rev limiter to 8k to help the oil pump keep up, so hoping the mid-range makes up any loss at higher RPM. Eventually, when I get my 4.10 gear set it won't matter anyway.

Rubin

[Chrisyphus]

Good lord, how frustrating, man... I am sorry you're dealing with this. I know how it feels to buy a car because you know it's good because it was obviously well maintained only to learn that it was a polished turd.

While living in Romania, I bought a 335i (they tax on displacement there, and going over 3 liters puts the car in an insane luxury tax bracket that would have me paying ~5000/year to register it... yeah, nah) and it was the highest priced example on the market, had an excellent pedigree, solid build- M3 rear end, forged rotating assy, nice coilovers, immaculate inside and out, and was well known in the car community there. When I picked it up, I had a PPP done, everything checked out, and I paid the premium. Two weeks later, it overheated because the coolant was full of oil. Classic OFHG failure. Replaced it, flushed coolant, and whammy... Two more weeks passed, and the same issue. Turned out to be a hairline crack in the head. $10,000 later, and I had a completely new engine, upgraded turbos, and all the bells and whistles. Then the turbos went out lmao. Later, I found a YouTube video where the previous owner had the same issue on their way to Wörthersee in Austria. He knew what he was selling and polished the turd. Bucharest is a big city, and I never saw him again, took the L on the chin. But Filip Stoica has an enemy for life, LMAO.

Obviously, your situation is different. I dont think your seller was trying to get anything over on you, but still, the frustration is real.

Moving on, it's not really my place, and you're in good hands with Rogue, but I have some questions and feedback-

Originally Posted by DrFerry

PS: The S65 OEM sump baffles, dual oil pickup and dual 'wing' design has successfully allowed many forum members to participate in HPDE and Pro-Solo track events, so something is definitely up with the failure circumstances you unfortunately experienced. Good luck with the Sherlock Holmes part of the failure analysis and investigation.

Originally Posted by former 240 s14

Additional Note: This vehicle has had 3 engines with 3 different drivers. Each engine has experienced rod bearing/main bearing failure. The only common denominator is it had the same engine builder for all 3 engines (performing at a minimum rod bearing service.) During the tear down, I found inconsistencies I would not expect from a reputable shop.

Originally Posted by omgzirra_exe

personally just my opinion if cost allow.

I would 100% WPC the entire rotating assembly, main bearings if you are sticking with standard clearance or even extra clearance, rod bearings, the pistons, the rings, etc.

100% worth the very reasonable expense in my opinion. We do not use WPC cranks or cams, but we have every single bearing we use WPC-treated across the board. Izumi is great, they are incredibly fast, and do excellent work.

Originally Posted by former 240 s14

These included....

1. Breakaway Torque values ranging from 35(ish) ft lbs to 45 ft lbs on rod bolts.
2. Un-torqued oil pan bolts
3. Stripped bolts
4. Motor mounts finger tight
5. Failure to consistently lube EVERY rod bolt. 2 of the 16 had zero assembly lube.
6. Potentially misclocked vanos gears

Y i k e s .

1. Man was out here using standard ugga duggas instead of metric....
2. Elbow must have run out of clicks...
3. Three ugga duggas were one too many.
4. What's it gonna do? Fly away?
5. Well, shop supplies are expensive. Have you seen the price of brake clean lately? I had to buy actual wasp spray to kill the wasps in our shop.
6. How do you even...? I mean, did he not use a timing kit?

I'm sorry for joking, this is so bad that if I dont laugh, I'll cry.

Originally Posted by former 240 s14

I am waiting to say the name of the shop still as Rogue needs to inspect the main bearings. I want the tear down to be completed before I potentially affect the reputation of a shop.

You have the patience of a saint. Seriously, hats off to you. But at this point, I feel you are obliged to call them out.

Originally Posted by former 240 s14

I have learned a metric ton of information about the S65 and BMW's decision making to compromise the construction of this engine to make it a better street friendly setup. At the end of the day the weekpoint of this engine has always been bearing support, however a few items are really worth noting.....

1. Oil Temp -
Higher Oil Temps are fine for street use. You don't stay in the high rev ranges like you do in track. With the increased temperature, the viscosity of oil decreases. This affects oil volume flow rate, especially as RPM's increase to redline. Keeping oil temp in the low 200's is ideal for viscosity. We are talking 220ish.

This is a little off the mark-
Youre not wrong that cooler oil + higher viscosity, but that is not the whole story. Oil weights are chosen for their viscosity performance in expected thermal regimes, and expected shear loading. If we were talking about a 40 or 30 weight, I would be inclined to agree with your desired temperature ranges, but Redline (we exclusively recommend Redline 10w60) recommends 10w60 for the S65 because they expect us to be running north of 255f, with the car only going into limp mode at 300f. Redline oils have EXCELLENT thermal stability, evaporating only 6%/hour at 498°F. IMO, if you can keep your oil temperature under 265, you are in very safe territory as long as you are using good oil.

The idea that higher temps are better for street driving revolves around fuel efficiency, not component protection. No, thank you, Honda, I am not interested in running 0w20 with a 220f thermostat to get a few extra MPG to bring your fleet fuel economy penalties down, at the expense of my engine at 60,001 miles.

Originally Posted by former 240 s14

2. Oil Flow -
Oil flow rate is more important than oil pressure, as oil pressure is a direct result of oil flow. The OEM oil pump has trouble keeping oil flow at desired ranges the higher the engine revs.

This is valid, but there is some nuance. Sure, with insufficient flow for a given restriction (bearing clearances), you will not generate pressure. But you can have all the flow in the world and not protect your bearings if there is no pressure in the system. The oil flow cools and lubricates where it reaches, but without pressure, there is no chance it will evenly cover all of the surfaces with a protective film.

Originally Posted by former 240 s14

3. Bearing Clearance -
Tight bearings are fine for street use and help keep oil flow strong at lower RPM's. Unfortunately when you track your M3 as hard as we do these bearings are counterproductive for oil flow at high RPM's. BMW figured this out for the bearing changes but never went far enough.

Straight Facts. lol, these super tight clearances really hurt cooling in the journals.

It was a strange time in the mid 2000s when the Germans were coming up with all these high RPM V8s... looking at you too, Audi. There was a major philosophy shift (that they ultimately stepped back from) in engine design as a result of improved manufacturing and metallurgy. theoretically, a tighter bearing clearance will form a more uniform wedge on the bearing with a lower viscosity oil, thus allowing for a more fuel-efficient engine for the doctor/owner while commuting into town from the suburbs, that could also rev to the moon and deliver the on-track performance that we all love. It was a classic case of wanting to have your cake and eat it, too.

Again, theoretically, this works. But in the real world, this meant zero tolerance for poor maintenance, low tolerance for added power, and near-zero tolerance for unexpected use cases. Particularly jumping in a cold car and sending it because you're late to your meeting, because the oil pump's internal bypass would allow exceedingly small volumes of oil flow through the bearings while they RAPIDLY heat up.

Originally Posted by former 240 s14

My Fix:

Ideally I would be running a dry sump system, but I unfortunately don't have $10k laying around in my couch. So with this I decided on the following:

1. Rogue Engineering is now selling SRD S65 Oil Pump Gearing - These gears utilize the OEM gear pump chain and overdrive the pump +21%. There is a 15 page engineering brief on these gears and their development, you gotta read this yourself!

This is a good call; we are using them in our engine builds. As someone else mentioned, we are overdriving a pump that already flows more oil than the engine needs, but the fact is that it simply means that, in situations where the pump is flowing too much oil, it will simply bypass more oil. And if the looser clearances are causing pressures to drop below optimal, the overdriven pump will bridge the gap. I do not see a downside beyond, potentially, more wear on the pump, a slight increase in overall parasitic drag, and a small amount of additional heat generated by the extra work done on the oil itself.

Originally Posted by former 240 s14

2. Epic Motorsports Oil Diverter Kit - although this negatively impacts street driving it's a must for aggressive track weekends

This, too, is an excellent call for a dedicated track car. The OE oil thermostat and related ports are problematic- even while completely open, the thermostat itself is too restrictive, and the ports in the system allow too much of the oil to bypass the cooler, reducing flow through the cooler and ΔT of the cooler as a result. This drastically reduces the heat exchanger's efficiency as a function of ΔT

We are working on a better solution that makes no sacrifices to street or track performance and can be used with the OE or any other oil cooler setup.

Originally Posted by former 240 s14

3. AAF Oil Pan baffles & BW Dipstick Kit

Can't miss here, IMO.

Originally Posted by former 240 s14

4. Custom machined OEM crank to be matched with ACL Race Bearings - Rogue is doing the measurements of my crank with the physical bearings I will be running.

Yeah, good call. I think I saw somewhere else that you were considering machining the block itself for extra clearance on the top side of the main... I would advise against that. The issue, we think, is not the tension from the timing chains or the serpentine belts. We have measured expansion of the #1 main on the crank with torqued crank pulley bolts. I could not believe it when Peter told me it could happen, then he proved it with the mic.

Originally Posted by former 240 s14

5. Accusump - this system has been proven to help with oil volume during oil starvation situatons.

6. Epic Tune - Will have this tuned by EPIC and I will be LOWERING RPMS to 8000-8100. [/QUOTE]

Certainly no danger in being conservative.

Originally Posted by former 240 s14

7. Potential relocation of Oil Cooler to trunk - This helps weight obviously, makes the accusump install much easier, and keep the cooler away from the hot engine. I am going to run a fan and have a section of the trunk cut out for flow.

I think this will hurt more than it will help in terms of thermal management, but I cannot say for certain. If I understand correctly, this is a road course track car, not a drift car. There are different considerations at play. Youre not sliding sideways at relatively low speeds, filling your heat exchanger with rubber and debris. Additionally, the only heat source that could radiate heat to your oil cooler is the radiator itself. Moving your oil cooler away from the extreme high-pressure zone at the front of the car, where it is one of the first things to receive ambient airflow, in favor of the trunk with fans, seems very counterproductive.


Turns out it was more feedback than questions. My second read-through answered most of my questions, lol.

[Chrisyphus]

Originally Posted by Brandoch

It's definitely a challenging diagnosis.
-Bearing clearance too tight
-Super thick oil
-Long crank snout
-2 double timing chains
-2 serpentine belts
-4 bolts on the front of the snout for the crank pulley
-8400 RPM

100% true. Lots of extreme dynamics are happening all at once.

The S65's MPS is 4200 FPM, hitting a peak of 6770 FPM @ 76*. This represents oscillating between +6770 FPM and 0 every .0035 seconds. This represents an acceleration of over 1,989 Gs.

This means that on average, in acceleration, the piston alone weighs 2,131 pounds and is likely much higher at peak acceleration.

Because of the magnitude of this force, I am unconvinced that the #1 main bearing issue is the result of the load on the crank pulley and timing chains, even though they are creating a single shear load on the #1.

[Chrisyphus]

Originally Posted by former 240 s14

All I can do is try to prepare for worst case scenario (as it seems to follow me anywhere I go, lol.)

Mood.