What really kills the balance shafts?

[R-J]

Recently picked up an '06 A4 2.0 with a busted cam chain tensioner. The tensioner's plastic chain runners were broken but hard to say if that happened before or after chain/tensioner failure. Will be installing a new one as well as replacing any bent valves I might find. Timing belt was not broken. I pulled off the pan and inspected the pickup and no major blockage there but will be installing revised pickup. Balance shafts spin freely with no lateral play. So, I'm no trying to figure out if I should clip the balance shaft gear or even send it out to have the proper balance shaft delete done while I have the pan off or if it's not really the big issue some people will have you believe. I will be keeping the original 2.0 oil pump. Would appreciate your thoughts on what is potentially killing balance shafts and ultimately causing catastrophic engine failure. Don't want to be Chicken Little unnecessarily worrying about the sky falling.

[gyroscope]

Recently picked up an '06 A4 2.0 with a busted cam chain tensioner. The tensioner's plastic chain runners were broken but hard to say if that happened before or after chain/tensioner failure. Will be installing a new one as well as replacing any bent valves I might find. Timing belt was not broken. I pulled off the pan and inspected the pickup and no major blockage there but will be installing revised pickup. Balance shafts spin freely with no lateral play. So, I'm no trying to figure out if I should clip the balance shaft gear or even send it out to have the proper balance shaft delete done while I have the pan off or if it's not really the big issue some people will have you believe. I will be keeping the original 2.0 oil pump. Would appreciate your thoughts on what is potentially killing balance shafts and ultimately causing catastrophic engine failure. Don't want to be Chicken Little unnecessarily worrying about the sky falling.

Seems to be covered in this video

[aluthman]

Seems to be covered in this video

That’s not our engine...

To answer the question though, I firmly believe that poor oil change habits and burned through cam followers have more to do with balance shaft failure than anything else. High rpm certainly doesn’t help either, so driving around at redline all the time would be ill advised. If it’s just a car for commuting, I’d probably leave the shafts alone. If you are building for power, I’d clip them or buy a new pump like I did.

[griga]

^ It seems to be a problem among poorly maintained cars and high power applications.

Not sure I’d call it common as I’ve seen numerous Stock and Stage 1 cars reach 200-300k miles. But with the amount of people that buy these cars with poor or unknown maintenance history, and then come here when there’s a problem, it does seem “common”.


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[a4lownslow]

Cam follower failure is absolutely the number one cause of oil pressure issues, balance shaft failures. The thing is once the follower fails, sure you can put a new one in and drive the car for who knows how long. 10, 20, maybe a hundred thousand miles, but the fact is once those small metal fragments circulate through the oil galleys there is just no way to get them out. It’s a slow drawn out process but believe me when that engines fails it stems from the follower failure. I own a small dealership selling only Audi vw. I’ve probably sold over 40 b7 2.0t in the last 1.5 years and have seen countless engines failure around the 100k mark. My trusted Audi mechanic (who was a tech for 25 years before opening his shops) believes these are one of the worst engine, and I have begun to have the same mindset. The 2.0TFSI is a mech better engine. Obvious piston rings and timing chain need to be addressed, otherwise they’re pretty solid. They don’t really leak oil like the FSI either which is nice.

Another tid bit, next time you do an oil change. Drain your oil into a perfectly clean bucket, then dump that slowly into a holding container. See how many flakes sit in the bottom. Open the filter element and see how many flakes are in there. Bet you it won’t look good

Sad part is we aren’t the engineers, we just try to make the cars as best as possible. The reality is they have major inherent flaws.

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[Jay-Bee]

My car was previously fully serviced by an Audi dealer, followed whatever oil change interval the computer said to do (likely 15,000kms) and whatever oil the dealer used, oil pump/balance shaft failure @ 112K kms.

Brand new engine was swapped in 25,000 kms before i bought it. Been keeping it nice and healthy with Castrol 0w40 7500-8000km OCIs and a few Liquimoly cleaners/additives.

[Kevin C]

GDI engines produce soot from rich combustion areas that ends up in the oil. That soot can cause abrasive wear to certain sliding surfaces. In particular wear surfaces that do not form a hydrodynamic film during operation but still have a high pressure loading. One theory is that the film on the metal surfaces formed by the EP additives gets removed by the soot particles and then reforms. The new surfaces gets the new EP layer removed again so it reforms. That happens on a continued basis eventually causing the part to lose enough metal that it fails. Fresh oil with more anti wear additives can actually have a higher wear rate. Its also why having the right oil matters.

Over time the soot also thickens the oil. My take is this is what clogs the oil rings.

Sootis likely to migrate into the oil film early during the expansion stroke[8]; consequently, the morphology, agglomeration and other charac-teristics of soot-in-oil are likely to be rather different to exhaust soot.Soot-in-oil has not been subject to oxidation processes to the same extent and hence the outer shell structure is more likely to remain intact. Although only a small proportion of the soot formed in the combustion chamber transfers to the engine oil, it contributes to the lubricant degradation. This is certainly a new challenge for the modernGDI engine as soot-in-oil raises concerns upon wear and engine durability. It is well established that oil thickening has a complex dependence on soot

A bit more: Does this time chain wear elongation sound familiar, yes chain wear is a byproduct of GDI and its interaction with engine oil.

Soot reduces the effectiveness of anti-wear additives and its effect on wear depends upon the characteristics of the particles and agglomerates of soot. Abrasive wear occurs and wear scar width closely matches the primary particle size [10]. Oil thickening was found to enhance timing chain elongation due to abrasive action of soot on pins and bushing [13]. Bardasz et al. [14] studied the influenceof high number of engine cycles on lubricant oil and that of oil characteristics on engine wear, comparing direct injection and port fuel injection engines and finding increased wear for the first category.There is also a growing interest within the automotive industry to better understand the complex interactions between soot morphology and properties of lubricating oi

https://www.researchgate.net/publica...ron_Microscopy

[Kevin C]

Still no oil rating to address GDI issues?

https://www.fuelsandlubes.com/still-...of-ilsac-gf-6/

[Sul_Reed]

The root cause of failure to my engine @ 210,000 was a worn through cam follower. The metal fragments got into the oil pump and wrecked havoc.

[Kevin C]

The root cause of failure to my engine @ 210,000 was a worn through cam follower. The metal fragments got into the oil pump and wrecked havoc.

The hard part is getting to the root cause of the cam follower.



https://link.springer.com/article/10...249-018-1115-x

Previous work has shown that the engine oil anti-wear additive ZDDP can behave as a pro-wear rather than an anti-wear agent when soot or other solid nanoparticles are present. This is believed to originate from the soot abrading the ZDDP tribofilm as rapidly as it forms, resulting in a corrosive-abrasive wear mechanism. There is, however, another key additive present in engine oils, the dispersant, which is essential to maintain soot in suspension. This additive is designed to adsorb on soot particle surfaces and is also known to interact with ZDDP. It is thus of considerable interest to establish the role, if any, that this additive plays in soot wear.

In the current study the influence of dispersant on soot wear with ZDDP has been studied using a range of different succinimide dispersants. Carbon black (CB) has been used as a soot surrogate. The most significant findings and conclusions from this study are summarised below:

HFRR wear tests show that when ZDDP is added to solutions of dispersant and CB, much more wear occurs than when ZDDP is left out. ZDDP thus has pro-wear properties in CB solutions, confirming previous studies.

The rate of wear seen with ZDDP and CB increases with phosphorus concentration, suggesting that the ZDDP reaction with ferrous substrate is a rate-determining step in the wear process.

Further HFRR tests show that both dispersant concentration and type strongly influence the wear induced by CB in ZDDP-containing oils. Most dispersants show a maximum of wear at ca 0.02 wt% N, which is around the concentration used in fully formulated engine oils. Much less wear is seen at very low and at high dispersant concentrations.

A few dispersants do not show this high wear behaviour at intermediate concentrations and instead enable low wear over the whole concentration range studied. These appear to be succinimide dispersants combining high functionality and high MWt.

The increase in wear with increasing dispersant concentration at very low dispersant concentrations is believed to originate from an increase in the ability of CB particles to enter the rubbing contact as they become better dispersed.

Two possible origins of the lower wear seen at high dispersant concentrations than at intermediate concentrations for most dispersants have been identified. These are: (i) at high concentrations dispersants may interact with ZDDP molecules in solution or at surfaces to reduce the latters’ reactivity and thus slow ZDDP reaction with rubbed surfaces; and (ii) at high concentrations dispersants may protect the initial ZDDP tribofilm from abrasion by adsorbing effectively either of the tribofilm itself or on the CB particles.

The rates of ZDDP film formation by CB-free ZDDP blends containing dispersants that give high wear at intermediate dispersant concentrations are similar to those formed by blends containing dispersants that give low wear. This suggests that mechanism (i) above is not prevalent. Preliminary studies of the very thin ZDDP tribofilms present on rubbed surfaces when ZDDP and CB are present indicate that dispersants that enable low wear at intermediate concentrations are able to protect iron sulphide films on the rubbed surfaces, in support mechanism (ii) above.

It is thus proposed that when ZDDP and soot are both present in an oil, the ZDDP reacts with the rubbed surfaces to form a film of iron sulphide that may be immediately abraded by the soot particles, resulting in rapid corrosive-abrasive wear. Key to this is that the initial tribofilm formed by ZDDP is iron sulphide and this is normally subsequently overlain by a protective zinc phosphate film [28]. However soot prevents build-up of this zinc phosphate film, thus allowing iron sulphide formation and removal to continue unchecked.

High concentration levels of dispersant, and in particular some highly functionalised dispersants, appear to be able to protect this iron sulphide film from abrasion and so prevent the very high levels of wear otherwise seen with oils that contain both ZDDP and soot.

[aluthman]

The hard part is getting to the root cause of the cam follower.



https://link.springer.com/article/10...249-018-1115-x

It's just a bad design... No sense in trying to re-engineer the follower itself. Either replace them at a regular interval or do the roller follower conversion.

[a4lownslow]

It's just a bad design... No sense in trying to re-engineer the follower itself. Either replace them at a regular interval or do the roller follower conversion.

The problem is for anyone buying these cars second hand you have no idea if the follower has worn through previously.


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[aluthman]

The problem is for anyone buying these cars second hand you have no idea if the follower has worn through previously.


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Yeah, not a lot you can do about that.

[Kevin C]

It's just a bad design... No sense in trying to re-engineer the follower itself. Either replace them at a regular interval or do the roller follower conversion.

I don't disagree that the design has issues and we know that there is a solution, what I was getting at is why was is the original design bad. There is several common failures on the 2.0 and they are probably all oil / GDI particulate related. Basically the same issue that causes drive chains to fail is what causes the cam followers to fail (and oil rings to clog). All of those erosion wear issue can put larger metal particles into the oil that contribute to the balancer shaft bearings failing. The oil ring clogging also causing an interesting side effect of you have an engine that's constantly running low on oil and possible compromising oil delivery. Since the balance shaft run at 2X engine speed they don't like to be starved.

[Theiceman]

I don't disagree that the design has issues and we know that there is a solution, what I was getting at is why was is the original design bad. There is several common failures on the 2.0 and they are probably all oil / GDI particulate related. Basically the same issue that causes drive chains to fail is what causes the cam followers to fail (and oil rings to clog). All of those erosion wear issue can put larger metal particles into the oil that contribute to the balancer shaft bearings failing. The oil ring clogging also causing an interesting side effect of you have an engine that's constantly running low on oil and possible compromising oil delivery. Since the balance shaft run at 2X engine speed they don't like to be starved.

What exactly are you asking,? I'm not sure if you are trying to ask us something or tell us something.
The cam follower is a bad design because it's a flat tapet. The oils to support flat tappet design went away with modern oils where levels of zddp were regulated out of oils. The roller type of tappet or even a hydraulic lifter type would have been superior.
Personally outside of that I dont have issues with the design. But maybe some issues with materials testing dept, plastic bits dont last long enough in my mind.


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[aluthman]

What exactly are you asking,? I'm not sure if you are trying to ask us something or tell us something.
The cam follower is a bad design because it's a flat tapet. The oils to support flat tappet design went away with modern oils where levels of zddp were regulated out of oils. The roller type of tappet or even a hydraulic lifter type would have been superior.
Personally outside of that I dont have issues with the design. But maybe some issues with materials testing dept, plastic bits dont last long enough in my mind.


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I also think the forces put on the cam follower are simply too much for it to hold up. Flat tappet cam designs only had to overcome a valve spring and open a valve. Our cam follower had to push against a spring and compress fuel to well over 100 bar. The stress seen on the follower in doing this explains why the design doesn’t hold up.

[B6fan]

What replacement interval is recommended for the cam follower?

[EvolutionArmory]

What replacement interval is recommended for the cam follower?

The real answer is before it wears out. It really depends on your state of tune, how much fuel it’s asking for and how that pressure affects its wear.

I do mine every year which is about 30k miles. I could probably go 40-50k because the ones I pull out are worn but not nearly bad enough.

[Redryuu]

The real answer is before it wears out. It really depends on your state of tune, how much fuel it’s asking for and how that pressure affects its wear.

I do mine every year which is about 30k miles. I could probably go 40-50k because the ones I pull out are worn but not nearly bad enough.

I do 30k km, can go longer but rather not have a nasty surprise when I go to pull one

[aluthman]

I replace mine about every 10k miles currently, but I bought the roller follower conversion that will be going on soon.

[Kevin C]

I also think the forces put on the cam follower are simply too much for it to hold up. Flat tappet cam designs only had to overcome a valve spring and open a valve. Our cam follower had to push against a spring and compress fuel to well over 100 bar. The stress seen on the follower in doing this explains why the design doesn’t hold up.

I'm a mechanical engineer and have worked qualifying drivetrain parts that ended up in GM diesel engines ( long time ago). Right now I'm in an entirely different industry but we still have to do rigorous qualification studies and tests. From that perspective I'm wondering how did the powertrain engineers at Audi miss this. For a lot of reasons designs are supposed to have a factor of safety. That factor of safety is what allows us to get more out of an engine and not (hopefully) have it blow up. The engines all were dynoded and test driven with some type of halt testing ( highly accelerated life test).

So what did Audi miss?

The other part, is on the same engine we have piston rings that clog as well as timing chain stretch / wear that is 2-3x higher than the last engine (1.8T)

Did the qualification program miss all of those or is there a common factor that may not have shown up in the testing program.

That's what I'm curious about.

A bit of reading and research showed that other GDI engines had similar issues with the timing chains and its attributed to combustion particulates (PM) that are specific to GDI engines.

A bit more reading shows that the combustion particles interact with the ZDDP additives to wear certain components at a much higher rate than port injection engines.

That interaction appears to be depended on the detergent additive level and the PM loading, oil viscosity, loading and temperature.

Short story is that with the wrong combination oil viscosity and additive package (and oil age) you can have a lot of wear problems. If you stay on the other side of the line the motor works as designed.

Short story is I found some interesting research on GDI and wear issues and figured I would share. My take is that the real world PM loading was worse than what they got during qualification.

Specifically:

https://link.springer.com/article/10...249-018-1115-x

"The main evidence for this is that when both zinc dialkyldithiophosphate (ZDDP) and the soot surrogate carbon black (CB) are present together in a lubricant, the combination can lead to much higher wear than if either ZDDP or CB is absent. Booth et al. studied additive combinations with CB using factorial analysis that showed that primary ZDDP appeared to increase pin wear [24]. They showed that blends containing both ZDDP and CB exhibited high wear on the ball, which they ascribed to “immature” anti-wear film formation. In 2010, Olomolehin et al. investigated the influence of CB and other nanoparticles on wear in anti-wear additive-containing model lubricants [19]. They found that when CB was added to an oil containing ZDDP, the combination gave much more wear than when no ZDDP was present; i.e. ZDDP became pro-wear. They suggested a corrosive-abrasive mechanism in which the CB removes the initial iron sulphide and phosphate anti-wear film as rapidly as it forms, leading to a rapid loss of ferrous compounds and thus high wear levels. "

[V70R]

What exactly are you asking,? I'm not sure if you are trying to ask us something or tell us something.
The cam follower is a bad design because it's a flat tapet. The oils to support flat tappet design went away with modern oils where levels of zddp were regulated out of oils. The roller type of tappet or even a hydraulic lifter type would have been superior.
Personally outside of that I dont have issues with the design. But maybe some issues with materials testing dept, plastic bits dont last long enough in my mind.


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I’ll refute this statement.

Aircooled aircraft engines have primarily used flat tappet camshafts utilizing engine oils lacking ZDDP. Their maintenance intervals may be more periodic than other internal combustion engines, but camshaft wear due to a lack of additive is not present. This also is true with Jeep’s 4.0 I6 that used flat tappets and frequently exceed 200,000 miles with or without ZDDP.

A similar HPFP design is used on Mazda DISI engines where it’s not uncommon for owners to exceed 100,000 miles on their original cam follower, camshaft and HPFP with no visual wear. Volkswagen has a history of camshaft hardness issues dating back to early 2.0 ABA’s and early Mk4 VR6 engines, even to the 3.0 (B6/C5) and newer TDIs where they would lose cam lobes; revised camshafts usually resolved this problem but many speculate the primary cause to be oil circulation and lubrication. This is where I think the problem is in EA113 motors.

[Theiceman]

I’ll refute this statement.

Aircooled aircraft engines have primarily used flat tappet camshafts utilizing engine oils lacking ZDDP. Their maintenance intervals may be more periodic than other internal combustion engines, but camshaft wear due to a lack of additive is not present. This also is true with Jeep’s 4.0 I6 that used flat tappets and frequently exceed 200,000 miles with or without ZDDP.

A similar HPFP design is used on Mazda DISI engines where it’s not uncommon for owners to exceed 100,000 miles on their original cam follower, camshaft and HPFP with no visual wear. Volkswagen has a history of camshaft hardness issues dating back to early 2.0 ABA’s and early Mk4 VR6 engines, even to the 3.0 (B6/C5) and newer TDIs where they would lose cam lobes; revised camshafts usually resolved this problem but many speculate the primary cause to be oil circulation and lubrication. This is where I think the problem is in EA113 motors.

I

will refute this statment as I have rebuilt flat tappet race engines that show otherwise. Hardened cams that have accelerated wear when moving away from zddp based oils that have these anti wear additives. So there you have it.
I will ask how many of your quotesd engines have you personally rebuilt inspected and evaluated.

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[Kevin C]

ZDDP and CB can interact to increase wear. I have data that shows cam followers failed faster with oils that had high levels of ZDDP.

Good read:

https://www.stle.org/images/pdf/STLE...ry%20Plays.pdf

Timing chain wear and ZDDP:

zinc.JPG

Actually the Mobil 1 that meets Audi specs for the B7 has a phosphorus / zinc level of 1000/1100 ppm (502.00, 505.00), compared to other current oils that are in the 800 ppm range that decent. ZDDP above 1400 ppm actually increases cam wear. Also there are additives other than ZDDP that prevent high pressure wear. ZDDP was not removed from newer oils, in some oils the allowed maximum amount was limited.

https://www.experimentalaircraft.inf...-additives.php

Why aircraft engine don't use ZDDP:

Aircraft engines burn a fair amount of oil and, if these metal-containing detergents and antiwear compounds are present, they can form metallic ash deposits in the combustion chambers. These deposits can lead to destructive preignition, which could burn holes in the tops of pistons with obvious catastrophic results. For that reason, it was decided that aviation oils were to remain ashless to avoid the risk of metallic deposits.The benefit of using ashless dispersant oils is, obviously, a cleaner engine. Aircraft engines would also benefit greatly from the addition of other automotive additives such as anti-wear, detergents, and corrosion inhibitors, but the downside is added cost. Ashless versions of these performance additives can cost up to 10 times more than standard ash-containing additives.

[Kevin C]

I just finished a teardown of a 2.0TFSI. A few observations.

1: At 140,000 miles it had some clogging of the pickup tube but is was not all that bad. Over its life the motor had eaten at least one fuel pump cam follower (see photos).
2: The 2.0TFSI engine is generating more metal than other designs (fuel pump cam and follower). Not all of that metal gets filtered and some ends up embedded into the bearing surfaces (filters are not 100% efficient, some junk always gets by). I found a few particles in the mains, nothing too bad, the bearings have good embeddability and the crank did not get scored.
3: Not all bearing surfaces handle metal equally well. The mains and rods are designed to have a good level of embeddability. Bearing surfaces generated by machining a casting dont tolerate debris as well as the mains and rods inserts that are made from multiple layers of soft metals on a hard backing.
4: When the machined in bearings in the head or the oil pump assembly encounter debris that don't readily embed that particle stays proud and scores the the journal of the shaft. That generates more debris and can cause a cascade effect that wipes out the entire bearing surface.
5: Softer shafts on cams (and possibly balance shaft units) are less tolerant of debris ( compared to a heat treated steel crank). The poor embeddability of the housing can also cause particles to embed in the camshaft and basically machine the housing away.
6: Balance shafts run at 2X engine speed and can be more susceptible to oil starvation (Mitsubishi 2.6 engines were known for this). It does help that Audi reduced the journal diameter so that the surface speed is lower.
7: The higher particulate contamination of a GDI engine stresses the oil more and can lead to pickup tube clogging. Especially true if the oil quality is an issue or if oil changes are skipped. GDI engines don't vaporize fuel as well as port injection engines, that creates a greater soot contamination that the oiling system has to deal with.
8: On engines that are using a lot of oil because of the piston ring problems its possible that the pump is sucking air now and again. That is really tough on bearings and can cause cavitation damage ( small chunks of bearing flaked out).
9: Fuel contamination from poor injectors reduces the lubricity of the oil. That can also cause cavitation damage.
10: If you combine fuel contamination with a partially clogged pickup, cavitation becomes a lot more likely. Cavitation reduces oil pressure and causes bearing damage.
11: Thickened old oil is more likely to bypass the filter on cold start (or increase the amount of time and volume of the bypass). That allows more cam follower debris to circulate, increasing the likelihood of damage.

Solutions:

1: Reduce the metal loading on engine ( keep an eye on the cam follower or upgrade).
2: Good maintenance, regular oil changes and check the oil for high fuel contamination.
3: Make sure your injectors are working right if the motor runs rough find out why.
4: It's possible that the higher particulate loading of a GDI engine loads the filters up faster and that increases the tiem the that leverlthe the filter gets bypassed. See not #2 on good maintenance just following the factor recommendations may not be enough ( i know that everyone here already knows that).
5: The dual inlet pump pickup is designed to address pump starvation and cavitation damage be allowing a second passage. A good first defense is to keep the pump pickup from getting clogged in the first place.

Summary:

The pump and balance shaft system itself is a good design , however it is living in a very harsh environment. If it's run with oil that doesn't sludge the pickup screen and normal level of metal contamination it will last as designed. As a side note my other car is a Dodge Raider with one of the original balance shafts systems. I have been running various versions of that 2.6 liter with a turbo for a really long time (since 1990). Done right the balance shafts make for a super smooth large four. Despite being a 1987, the four in my Raider is noticeably smoother than the 1.8T. If you want vibration try the 2.6 with the balance shafts removed. The amazing thing is some people can't tell the difference. Same debate we get on the Audi engines but this one is not even a little bit subtle, its vibrate the mirror enough so you can tell what vehicle is behind you bad. Some people think its fine not to have them.


2.0tfsi_Pickup.JPG2.0tfsi_Pickup2.JPG2.0tfsi_crank.JPG

[Kevin C]

Couple more pics...

On the subject of things that can hurt your oil pressure. My first reaction when I saw the big scratch was really.... Audi put a bearing in a motor that looked that bad?


Factory original bearing that's never been out or inspected. How did that get there? Thats a nasty scratch!

It sure looks like its cavitation erosion, I can't say I have ever seen one quite like this. I got a couple of snaps using a microscope and a cell phone. It might even be a combo of dirt progression marks and cavitation.



Bearings have a finite life and 140,000 miles had taken its toll on this set.



http://www.gbbearings.co.za/bdc05.html

bearing1.JPG

cavitation2.JPGcavitation1.JPG

[esandes]

Great thread. I also don't think it helps the balance shafts or oil pump integrity if the engine is bumping up against the rev or speed limiter.

[Theiceman]

Couple more pics...

On the subject of things that can hurt your oil pressure. My first reaction when I saw the big scratch was really.... Audi put a bearing in a motor that looked that bad?


Factory original bearing that's never been out or inspected. How did that get there? Thats a nasty scratch!

It sure looks like its cavitation erosion, I can't say I have ever seen one quite like this. I got a couple of snaps using a microscope and a cell phone. It might even be a combo of dirt progression marks and cavitation.



Bearings have a finite life and 140,000 miles had taken its toll on this set.



http://www.gbbearings.co.za/bdc05.html

bearing1.JPG

cavitation2.JPGcavitation1.JPG

Do you think micro fragments from a destroyed follower could have done this. ?
The rod bearings off my b8 looked almost brand new after similar mileage

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[Kevin C]

Do you think micro fragments from a destroyed follower could have done this. ?
The rod bearings off my b8 looked almost brand new after similar mileage

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Exactly what I was thinking. The closer I look, the more tiny dark steel specs I see. I will say the crank must be pretty tough to put up with what got into the bearings. This is from a long block I bought at a pick and pull for my 1.8T stroker motor (a deal for $160). I was lucky to find a motor with a crank for a manual shift.

My working theory is that if the oil pump and balance shaft set survived to 140,000 miles living on a diet of 10,000 mile old oil and chips of hardened steel, what happens if you run it in a motor with 5000 mile oil changes and no metal shards? I'm guessing that the pump and balance shafts live a normal life like every other motor.

Where am I going with this and why am I'm interested? I have a plan for a new motor for my B6. What happens if you put a set of 1.8T Mahle stroker pistons in the 2.0 TFSI block (83mm bore) and bolt a 1.8T head to it (with a good set of rods of course)? The 06F block starts of with a 82.5 mm bore so going up .5 mm is a non issue (I'm assuming that the 2.0TFSI got a bit more wall thickness over the 1.8t block since it has a 82.5 mm bore (81 mm is stock for the 1.8T).

Basically use the balance shaft set from the 2.0TFSI on the early port injection motor to make a smooth running stroker for my B6. I know I take a load of crap for this idea since by now balance shaft are considered bad and why would anyone in their right mind retrofit them?

Two things...I'm not really in my right mind and I am pretty confident that it would work really well. Sure it would probably be cheaper to just buy a V6 S4 but I like building engines and this one should be fun. So there it is... My somewhat crazy idea.

[Theiceman]

Nothing wrong with playing. But you orobably know the balance shaft assembly is one of the weak areas of the 2.0 t.
But probably for the reasons we are mentioning.


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[EvolutionArmory]

I think the balance shaft assembly would be a nice feature on the port injected motor.

You wouldn’t have to worry about possible cam follower material wearing things down because there isn’t one, less engine soot because it’s port injected and you’d have a much more balanced motor. All the positives without the negatives we get with DI.

[oVeRdOsE]

NOTE : this is NOT a 2.0T Mann filter, but Ive noticed the SAME with 2.0T mann on my car.
This filter is on my N55 bmw, with 10 000km on it. BMW oil change interval is 16000km

Mann filters seems to clog easily. See pictures, there's no way this can get a nice and even flow. The filter must be in bypass all day long.
The inner filter plies are so stocked together that they seems to be one piece.

Mahle filter are not as this bad.

Also, having a magnetic oil drain plug and a catch can, will help to keep the oil cleaner.


IMG_20190526_093526.jpgIMG_20190526_093345.jpgIMG_20190526_093516.jpg

[Theiceman]

NOTE : this is NOT a 2.0T Mann filter, but Ive noticed the SAME with 2.0T mann on my car.
This filter is on my N55 bmw, with 10 000km on it. BMW oil change interval is 16000km

Mann filters seems to clog easily. See pictures, there's no way this can get a nice and even flow. The filter must be in bypass all day long.
The inner filter plies are so stocked together that they seems to be one piece.

Mahle filter are not as this bad.

Also, having a magnetic oil drain plug and a catch can, will help to keep the oil cleaner.


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Wow I think that's the first time I have seen a collapsed mann filter. I wonder how long it was in there for.

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[AudiKilla]

Never seen a MANN filter do that, I also have N55 engine.

[EvolutionArmory]

This is why you don’t do extended interval oil changes.

I’ve never seen a collapsed Mann or OEM filter either with regular 5,000 mile intervals.

16,000km’s or 10,000 miles is just too much.

[macantley]

on my 2008 model, my balance shaft bolt broke off at the chain cog, it broke off because the thrust washer from the engine actually fell out somehow (still have no idea how thats possible) and stuck right into the two spinning shafts on the oil pump balancer. I bought my car with 94,000 miles on it, i have no idea how long the thrust bearing had been stuck in it when i got the car, but i noticed i had metal in my oil filter from 94,000 miles to 110,000 miles (so 4 oil changes) and i figured it was the oil pump balancer that had failed because i had vibration at idle, i was not expecting to find the trust bearing wedged in the balancer. My oil pump chain was only spinning because it was wedged up against my oil pan and block, needless to say my block was junk from my crank moving around so much without the thrust bearing, my oil pan had a large groove cut into it from the oil pump chain, BUT with a new bolt on the oil pump my pump itself was as good as new. I reused my oil pump on the new "core" block that i got, moved my head and turbo over to the new block and put everything back together..... I'm a firm believer that the oil pumps fail because of lack of oil changes and/or camshaft follower failures. I'm sure that there can be the random failure with no real reason, but i think oil and CF's are the main cause.metal chunks in oil pump screen..jpgbalance shaft cog.jpgwhats this.jpgmetal in shafts.jpg

[Brillo]

I understand and agree with the relationship between CF failure, eventual balance shaft and oil pressure problems. What I still would like to know definitively is whether the oil pumped to the balance shaft bearings is before or after the oil filter. If it isn't filtered the frequency of BS bearing failure is quite easy to understand and I would consider this to be a major design flaw in the lubrication system. What makes me think it's unfiltered is that when the balance shafts have even a small amount of play in them, it seems to cause a major drop in oil pressure. If the BS bearing oil is after the filter it would be just one of several oil galleries being fed filtered oil. Also, since the oil pressure switch is before the filter (I believe) the BS bearing play wouldn't have such a dramatic effect on the oil pressure. Regardless, a good reason for frequent and regular oil/filter changes, use of a quality oil filter (Mann), and use of the proper oil viscosity (especially in winter so that the oil bypass valve is open as little as possible).

While CF failure is not the only source of metal debris in these engines, would love to know the frequency of BS failure/oil pressure problems in engines with no CF or cam chain failures that have enjoyed rigorous attention to the OCI.

[Kevin C]

I have been wondering the same thing and have the same concern. I hope to chart out the oil flow. If it is direct pump fed I would be curious to see if the factory put a screen in that gets clogged over time.

[oVeRdOsE]

Never seen a MANN filter do that, I also have N55 engine.

the filter is cut open because I wasn't able to remove it from the plastic inner cylinder.

Also, I tear it in half very easily with my fingers.

I do NOT put any additive in my engine, both the N55 and 2.0t are using liquimolly and both engine got the oil change before the recommended interval.

- bmw interval is 16000km (10k miles). Done @10000km (6250miles)
- 08 audi is 15000km, done @ 8000km (5000miles).

Both my car, mann filter look like this.

I did try many time mann, because depending where I go buy my oil, shops got mann or mahle. I still have some mann left in my garage, but its my last one for sure.

With BMW rod bearing problem in the past, even if its not an issue on N55, I wont take the chance to be in recirculating mode. Lets wait a bit to see how the mahle looks like, Ive just changed it.

[menace1930]

Seems like we have some very knowledgeable people on this subject so I will ask here. I've been dealing with an intermittent oil pressure warning in my car and dropped the panel to check the oil pickup tube. My pickup tub was fine however I found an alignment dowel in my oil pan. Does anyone know how the heck an alignment dowel could have ended up in there and where it could have come from?