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      07-28-2014, 05:42 PM   #375
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Except there is no combustion during engine braking?
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      07-28-2014, 05:48 PM   #376
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Quote:
Originally Posted by chris719
Except there is no combustion during engine braking?
Engine braking meaning when you downshift aggressively, not talking about coasting in gear and allowing the "engine to brake for you".
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      07-28-2014, 05:51 PM   #377
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So you're implying the wear is from the unloaded throttle blip? It still doesn't make sense.
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      07-28-2014, 06:18 PM   #378
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Quote:
Originally Posted by SenorFunkyPants View Post
High wear on the top bearing is caused by the combustion stroke....its why the wear is offset to one sihttp://cnmsocal.org/de depending on which bank of the V it came from.
Ok. senor funky pants. Does that mean the rod is flexing enough to distort the bearing during combustion? if the rod was stiffer would it be more uniform pressure on the bearing?
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      07-29-2014, 02:49 AM   #379
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AIUI The highest load on the rod bearing is during the combustion event where the downward force caused by the burning fuel pushes the top bearing shell against the crank, if the force is high enough the oil film can be squeezed out allowing metal to metal contact . Combustion chamber design extends the length of time that the fuel air combustion mix takes to burn so that the peak downward load is reduced. If the fuel air combustion is less controlled ie quicker (due to poor fuel, failed anti knock sensor etc) then the peak load increases and bearing wear is more likely, similarly increasing BHP (through supercharging etc) increases peak load and thus the potential for bearing wear.
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      07-29-2014, 05:42 AM   #380
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Quote:
Originally Posted by 96LTWM3 View Post
-Says bearing wear is normal on high rpm motors. "Either the bearings go or the crank does, guess which is more expensive?'
Unfortunately I don't think I've seen one where the bearings have failed and not caused subsequent damage to either rods, crank or block, etc.
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      07-29-2014, 06:50 AM   #381
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Quote:
Originally Posted by 96LTWM3 View Post
High wear bearings are on top and usually are, caused mainly from engine braking.


Also forgot to mention the bearings are in no particular order, they are random and I just put the ones that looked alike together for pictures. Sorry for lack of clarity, however fact is bearings shows wear.
That is not true, the combustion stroke is where the wear is from.

Quote:
Originally Posted by 96LTWM3 View Post
Thats a great question. Who knows how long my motor would have continued to run with no issue. 100k? 150k?

The issues we discuss arising from more clearance, weather they are from resized bearings or worn bearings, can still have worst affects rather then better. Crank walk is one that comes to mind if you have too much clearance or not enough oil flow.

http://www.jackstransmissions.com/pages/crank-walk
One would have to run alot of clearance to accomplish crank walk. The larger contributor to something like that is when you are piston guided and not rod guided. Depending on the box and barrel of the pistons they can have alot of rock. This could introduce crank walk but normal clearances will not do this.

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Originally Posted by MFL View Post
Of the journals are fucking contacting the bearings then it's not "by design" Lol.

Full dumbass.
True dat

Quote:
Originally Posted by chris719 View Post
I'm confused as to why engine braking would cause bearing wear on the top shell.

Maybe Kawasaki can chime in? That doesn't sound correct to me but I could be wrong.
If timing is not correct it can rattle the pistons on decel but not a issue on NA motors. Only time we have seen wierd wear is on high compression (16-17:1) on gasoline.

Quote:
Originally Posted by SenorFunkyPants View Post
High wear on the top bearing is caused by the combustion stroke....its why the wear is offset to one side depending on which bank of the V it came from.
True statement

Quote:
Originally Posted by chris719 View Post
Except there is no combustion during engine braking?
If the engine is turning it has combustion, some racing engines will kill all fuel on decel but the s65 does not do this. I have never heard of a production engine that does it. It makes transient throttle response abrupt and it is hard to tune out.
Quote:
Originally Posted by 4corners View Post
Ok. senor funky pants. Does that mean the rod is flexing enough to distort the bearing during combustion? if the rod was stiffer would it be more uniform pressure on the bearing?
The factory rod is just fine for our application. The carrillo rod is better but nobody is going to run the better rod unless they are going to a low compression build so we really wont know the outcome of that until someone builds one.
The bearings are not coming out of the saddle so the better rod would not be near as important as better clearance numbers.
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      07-29-2014, 07:57 AM   #382
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Quote:
Originally Posted by kawasaki00 View Post
If the engine is turning it has combustion, some racing engines will kill all fuel on decel but the s65 does not do this. I have never heard of a production engine that does it. It makes transient throttle response abrupt and it is hard to tune out.
When Bosch introduced Motronic in the early 1980s, full fuel cutoff on a closed throttle was introduced. To the best of my knowledge, all BMWs since that time have had zero fuel flow under closed throttle until around 1200-1400rpms (depends on the engine, but it resumes to prevent stalling). Similarly other makes behave in the same fashion. It's relatively easy to observe in action. I'm not aware of BMW changing things with the S65 in this regard...don't think it flows any fuel on a closed throttle as long as revs are above ~1200ish.
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      07-29-2014, 09:13 AM   #383
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Quote:
Originally Posted by CSBM5 View Post
When Bosch introduced Motronic in the early 1980s, full fuel cutoff on a closed throttle was introduced. To the best of my knowledge, all BMWs since that time have had zero fuel flow under closed throttle until around 1200-1400rpms (depends on the engine, but it resumes to prevent stalling). Similarly other makes behave in the same fashion. It's relatively easy to observe in action. I'm not aware of BMW changing things with the S65 in this regard...don't think it flows any fuel on a closed throttle as long as revs are above ~1200ish.
Maybe Benvo can look at a map and tell. It would be easy to see what is going on. I have seen many cars that do it this way but didnt actually shut it completely off, a small value still exists on the map table.
I could have mispoken on the s65 though
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      07-29-2014, 09:38 AM   #384
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Quote:
Originally Posted by SenorFunkyPants View Post
Combustion chamber design extends the length of time that the fuel air combustion mix takes to burn so that the peak downward load is reduced. If the fuel air combustion is less controlled ie quicker (due to poor fuel, failed anti knock sensor etc) then the peak load increases and bearing wear is more likely, similarly increasing BHP (through supercharging etc) increases peak load and thus the potential for bearing wear.
Good info. My comment about engine braking is what I have heard from 2 different local race shops, nothing scientific about my comments. So based on the info above only a loaded combustion cycle would have potential for bearing wear?
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      07-29-2014, 09:41 AM   #385
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Quote:
Originally Posted by MFKN3 View Post
Unfortunately I don't think I've seen one where the bearings have failed and not caused subsequent damage to either rods, crank or block, etc.
Agreed. If total failure occurs you will have lots of broken parts. However if you are talking about wear, then a bearing is designed to wear, where a crank is not.
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      07-29-2014, 10:48 AM   #386
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It's so awesome to have a true race inspired car that requires real race like maintenance. I feel like the real deal! Since this is such a remarkable design and the new m3/m4 is said to be more remarkable and race car inspired it make sense to expect similar awesome race car inspired maintenance. It must be in there somewhere. Perhaps a complete overhaul is required say every 60k or so. Just venting, back on topic.
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      07-29-2014, 11:21 AM   #387
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its worse than the FD rx7
I owned one
went 40k on origianl motor before I sold it.
my 2013 m3 went 20k and blew up
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      07-29-2014, 06:25 PM   #388
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ARGH!

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      08-22-2014, 05:54 PM   #389
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2008 M3, 62,833mi

Info
Vehicle: 2008 BMW M3, 6MT
Production Date: 12/07
Oil Used: TWS Motorsport 10W-60, 7500mi intervals
Mileage: 62,833 mi
Fuel: 91 Oct
Driving Habits: Street driving, no track use
Oil Analysis: None provided

Notes:
M3 was just purchased on used market, came in with audible ticking. After getting oil analysis performed, it was quickly scheduled in for bearing service. Engine failure imminent if not attended to immediately.

Bearings were replaced with WPC Treated Bearing Set & ARP Rod Bolts. Engine and oil cooler/lines flushed to clean out any remaining debris.

Images:


As seen, bearing #2 suffered the most damage, with all remaining bearings showing considerable wear. Bearing particles were visible in oil filter element, required flushing to make sure all particles were removed from engine, lines and cooler.

Blackstone Oil Report:


Driver is very lucky to be driving his M3 today.
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      08-22-2014, 06:52 PM   #390
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^wow! That is the most definitive Blackstone report I have seen yet and the bearings look as you would expect based on that. Great job catching that in time.
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      08-22-2014, 07:01 PM   #391
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Now I know if my copper says 40 it's past time to change the bearings.

And I won't be driving it 3000 miles and checking it again. Bearings ASAP.
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      08-22-2014, 07:11 PM   #392
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Have to be proactive with these bearings. Great job EAS! Wish you guys were closer.
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      08-22-2014, 11:34 PM   #393
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This report actually belonged to my car. I want to thank Tom @ EAS for being very professional and helpful during my whole ordeal.

After hearing some ticking from my engine, and being the anal audiophile I am, I quickly took my car to EAS to see what they had to say about it. steve @ eas gave it a listen and said he was 90% sure it was worn rod bearings that were making the noise.

What I really appreciated from Tom was that he actually advised me to try have BMW NA repair it since I was only 4 months out of CPO warranty. He didn't want to take my business right away, and said that I should come back to EAS as a last resort. In the meantime, he advised that I take and oil sample and send it to Blackstone.

Blackstone diagnosed my issue as rod bearing wear without knowing that I already had the assumption that I had this problem. This confirmed the problem for me and I proceeded to contact BMW NA about my issue.

BMW NA suggested that I take it to a BMW dealership to diagnosis my car, and they can then decide whether they will cover the cost of repairs. I took my car to Bob Smith BMW at Calabasas, CA for the diagnosis. They wanted to charge me over $2,300.00 for the diagnosis alone, the reason being that they claimed that dropping the oil pan and looking inside was the only way to surely diagnose my problem. Since any support from BMW NA wasn't even a certainty, I took my car home and gave Tom a call.

I brought in my car on Monday and EAS was finished with it Friday (today). I was very impressed with the workmanship and the thoroughness of the job. They made every effort to remove all bearing debris in the engine, and they did a terrific job. They even cleaned my entire engine bay. It looks like it was straight off the showroom floor!






They replaced the piston rod bolts with ARP rod bolts, which have threads that are 10x stronger than OEM bolts, and replaced my bearing with surface treated WPC bearings, which are more durable than OEM bearings without compromising clearance.

If any of you hear any ticking from your S65, don't take any chances. Stop driving the car, get and oil analysis, and give EAS a call!
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Last edited by surewin; 09-08-2015 at 01:05 AM..
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      08-23-2014, 04:28 AM   #394
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You're a lucky mofo. Engine looks spotless too!!

Normally ticking is too late and is rod knock or spun bearings.
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      08-24-2014, 07:51 PM   #395
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Quote:
Originally Posted by MFKN3
You're a lucky mofo. Engine looks spotless too!!

Normally ticking is too late and is rod knock or spun bearings.
I was pretty lucky! The mechanic at EAS said some of the bearings were about to spin! Some of them weren't even perfectly circular any more.

I even took the chance in driving 1.5 hours to drop the car off at EAS =P
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      08-25-2014, 12:32 AM   #396
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Quote:
Originally Posted by surewin View Post
I was pretty lucky! The mechanic at EAS said some of the bearings were about to spin! Some of them weren't even perfectly circular any more.

I even took the chance in driving 1.5 hours to drop the car off at EAS =P
Since the engine is coming apart, should've chucked a Stroker/Schick Camshafts in it.
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