Piston failure on 2017 C300 (55,000 Miles on Odometer)

[Sehnsucht Berlin]

Genuinely well done on the Lexus!! I'm sure it will serve you well and best wishes for your daughter. I appreciate the last thing anyone needs it BS from a car, dealer and manufacturer.

Yes indeed, I have too much troubles going on as it is with my daughter's health issues to be bothered with mechanic breakdowns or terrible customer service. The build quality of a Lexus (even an entry level model) is much better than a late model MB. Older Mercedes were made better, the cars made in the last 5-7 years are terrible.

 

[oigle]

I wonder why it is that just American engines are suffering? It must be a direct fueling issue or emmsions mix issue because from what I can read on various forums and tech bulletins, its a stock OM274 engine with all failures of both German and Tennesse built stock, of which we have thousands on the road in this country and I have never come across this fault.

Also, why does it only effect cylinder 1? If it was a piston material component issue I would expect all pistons to be affected with no real predjudice to location on the engine.

The logical side of my brain says there must be some kind of contributing factor specifically related to cylinder 1. Perhaps the shorter distance to the exhaust or inlet port on either manifolds causing a higher temperature in that part of the engine, running a slightly increased compression or back pressure or a higher atomisation rate causing a fatigue under load.

Reminds me of my time at BMW in the mid 90's when cylinder bores were burning out which was specific to countries using a certain type of unleaded fuel that was reacting to the nikasil lining on the aluminium block and burning the cylinder bores, in some cases warping the blocks entirely when the HGs eventually popped.

You may have a point re fuelling. US fuels are different. Base unleaded is only 87 octane as I recall from years ago. I wonder whether incorrect fuel usage could be a contributing factor.

 

[DSK]

If factors such as differing fuel quality would be a problem, why are manufacturers selling the cars in such markets (other than being greedy sods chasing profits at any expense)?

When building a car you know what markets you want to sell it in so surely, engines would be selected and built knowing full well what variables such as fuel quality etc are in each market. But, in a day and age where manufacturers are fitting fake vents, diffusers, exhausts and god knows what other crap, I guess the term 'a job well done' no longer rests in a quality product but, rather the number of units sold with marketing BS.

 

[Steve@Avantgarde]

It could be, keep in mind Nissan is making the engine blocks on behalf of Mercedes, and the engines are built in TN and Alabama (from what I could gather)

Are you saying there are no clever people in the midwest?

Take all the emotion out of it for a moment and take the perspective that your engine is a machine that breaks and goes wrong, even one with a Mercedes badge on the front. The only thing that makes you emotional over it is your expectation level from the machine you drive beliving that this shouldn't happen to you. Whilst I agree its a poor show from MB, the reason I make a very good living from fixing them is because they still go wrong.

So taking that view, whoever assembles the engines (which are mostly constructed using CMC engines anyway) arent responsible for the design, R&D and final production sign off of the engine from concept to material assignment and running software. Where in the world that happens is totally irrelevant also. People can be conditioned to work to certain parameters in any location in the world if given the right opportunity, training and equipment.

The reasons for failure of your engine lies with the manufacturer of those engines within that area of expertise of engine design and development which, people with a higher IQ of 75 have been employed by Daimler or Renault/Nissan to do. So whilst I appreciate your stress with it, it's wrong to make the sweeping statement you have.

Like I said, the issue seems to be confined to American vehicles, which means there must be a contributing factor somewhere to failure and I'm willing to bet it lies within the fueling/smog rules/atmospheric conditions which those engines operate under because the issue just isn't seen in Europe and it seems to be very mileage indicative, which means its a fatigue process over time with an end of life (50-60k miles) rather than a sudden mechanical failure which would have no mileage prejudice.

I gave my example of engines I worked with when I was at BMW. That was country specific, based on fuel additives which controlled emmsions laws within that particular country through fuel sale which was heavily goverened within the UK in the late 80's and early 90s with the abolition of certain fuels like 4 star leaded fuel and a compliance to specific unleaded fuels.

I believe this case with the OM274 to be similar somewhere. Pistons dont crack like that for no contributing factor or reason.

 

[Steve@Avantgarde]

If factors such as differing fuel quality would be a problem, why are manufacturers selling the cars in such markets (other than being greedy sods chasing profits at any expense)?

When building a car you know what markets you want to sell it in so surely, engines would be selected and built knowing full well what variables such as fuel quality etc are in each market. But, in a day and age where manufacturers are fitting fake vents, diffusers, exhausts and god knows what other crap, I guess the term 'a job well done' no longer rests in a quality product but, rather the number of units sold with marketing BS.

You can do all the simulated R&D you like, you can do all the pre-production testing you want, but there is nothing like real world use because then you have uncontrolled variables that you are unable to simulate.

I have worked in vehicle R&D and development with some highly talented engineers and designers who think they have covered every angle or issue until its -5'c on a winters afternoon at 3pm, when crawling in traffic having just stopped twice to pick up the kids and the local shop and something fails. Thats the reality.

Are you suggesting that car manufacturers love a reputation risking slap dash job at the hope of making a quick buck? Ludicrous if so.

 

[DSK]

I know a lot goes into R&D, it obviously does but, with so many cases and law suits against manufacturers over the last decade, something's clearly not working well behind the scenes. Its not due to a lack of intelligence or one wanting to deliver their best work or go the extra mile as we have good and bad throughout the world. I think its probably down to internal politics where some voices are not heard and acted upon or over ruled.

Also the general stance from many manufacturers under such extreme conditions when they should look to put things right is simply unethical. These 2 previous points are ones which allowed me to comfortably and successfully argue cases against BMW and Land Rover. Both had several opportunities to be 'reasonable' rather than try and fob me off with that usual smirk and two finger salute. They both paid for it in the end.

 

[Steve@Avantgarde]

I know a lot goes into R&D, it obviously does but, with so many cases and law suits against manufacturers over the last decade, something's clearly not working well behind the scenes. Its not due to a lack of intelligence or one wanting to deliver their best work or go the extra mile as we have good and bad throughout the world. I think its probably down to internal politics where some voices are not heard and acted upon or over ruled.

Also the general stance from many manufacturers under such extreme conditions when they should look to put things right is simply unethical. These 2 previous points are ones which allowed me to comfortably and successfully argue cases against BMW and Land Rover. Both had several opportunities to be 'reasonable' rather than try and fob me off with that usual smirk and two finger salute. They both paid for it in the end.

Well there is 2 ways of looking at that.

Each manufactuer can prove their competence and development of the product throught the data they have available through all their reasearch and testing, therein proving that they arent negligent in their build processes, which is usually the accusation.

They may also have the failed parts back in their hands, whether thats at dealer or factory level and prove there was a degree of external influence to failure.

There is also the argument that they (the manufactuer) (a) didnt run up the previous X amount of miles putting the wear and tear on the vehicle (b) may be suspicious of version of events to a failure (c) maybe be able to prove against your version of events (d) look at how many other similar vehicles are on the roads in the world without failure (e) look at the previous service and repair history and determine negligence on behalf of the owner.

If they caved to every request for goodwill of a failed component simply in the belief that something is immoral or unethical in someone elses opinion then it would cost them more than production itself. That's why there are lawyers to fight that small print out. In your case, you won, congrats, there must have been some probable cause there!

 

[ernieh]

On the OP's car a piston failed, but there are also many instances on the US forums of these engines being replaced due to 'wrist' pin (gudgeon pin) problems causing rattles. As it seems that modified pistons are now being fitted, is it reasonable to suggest that the eventual failure of the piston is the result of the death rattle of the pins going undetected or just simply ignored? Of course, the initial wear could easily be down to poor fuel causing knocking, as suggested.

Ernie

 

[Sehnsucht Berlin]

Are you saying there are no clever people in the midwest?

Take all the emotion out of it for a moment and take the perspective that your engine is a machine that breaks and goes wrong, even one with a Mercedes badge on the front. The only thing that makes you emotional over it is your expectation level from the machine you drive beliving that this shouldn't happen to you. Whilst I agree its a poor show from MB, the reason I make a very good living from fixing them is because they still go wrong.

So taking that view, whoever assembles the engines (which are mostly constructed using CMC engines anyway) arent responsible for the design, R&D and final production sign off of the engine from concept to material assignment and running software. Where in the world that happens is totally irrelevant also. People can be conditioned to work to certain parameters in any location in the world if given the right opportunity, training and equipment.

The reasons for failure of your engine lies with the manufacturer of those engines within that area of expertise of engine design and development which, people with a higher IQ of 75 have been employed by Daimler or Renault/Nissan to do. So whilst I appreciate your stress with it, it's wrong to make the sweeping statement you have.

Like I said, the issue seems to be confined to American vehicles, which means there must be a contributing factor somewhere to failure and I'm willing to bet it lies within the fueling/smog rules/atmospheric conditions which those engines operate under because the issue just isn't seen in Europe and it seems to be very mileage indicative, which means its a fatigue process over time with an end of life (50-60k miles) rather than a sudden mechanical failure which would have no mileage prejudice.

I gave my example of engines I worked with when I was at BMW. That was country specific, based on fuel additives which controlled emmsions laws within that particular country through fuel sale which was heavily goverened within the UK in the late 80's and early 90s with the abolition of certain fuels like 4 star leaded fuel and a compliance to specific unleaded fuels.

I believe this case with the OM274 to be similar somewhere. Pistons dont crack like that for no contributing factor or reason.

Fair enough, my statement about yanks in Alabama and TN not being highly intelligent is not a fair statement to be made in the case of terrible engineering on behalf of MB. The problem lies with Nissan and MB, both of which are cheap crappy companies that produce cheaply built cars. MB has been cheaping out on parts and providing terrible customer service for over 20 years now. Even with all the problems of 10-12-15 years ago the cars were just made better at that time. The last 5-7 years have been very problematic for most (if not all) auto manufactures across the entire industry. Not much of anything is built like it used to be. There are many factors that can contribute to premature engine failure. The problem in my situation was cylinder 1 (which seems to be the common problem), it has to be some sort of manufacturing defect that MB has not officially publicly acknowledged, hence why the engine update happened in 2018 and newer model years.

Octane ratings are a different measurement in the U.S. compared to that of which we see in the E.U.
I am not a petroleum engineer, as far as what is being put in petrol in Amerika compared to the rest of the world, that of which I can not speak on.

 

[Sehnsucht Berlin]

On the OP's car a piston failed, but there are also many instances on the US forums of these engines being replaced due to 'wrist' pin (gudgeon pin) problems causing rattles. As it seems that modified pistons are now being fitted, is it reasonable to suggest that the eventual failure of the piston is the result of the death rattle of the pins going undetected or just simply ignored? Of course, the initial wear could easily be down to poor fuel causing knocking, as suggested.

Ernie

The 2018 and newer model years have a redesigned gudgeon pin, MB knows damn well that there is a defect in the 2015-2017 model years but they are being cheap and lazy. Unless a class action lawsuit or some sort of Government investigation was to occur I doubt MB will own up to it.

 

[Sehnsucht Berlin]

If factors such as differing fuel quality would be a problem, why are manufacturers selling the cars in such markets (other than being greedy sods chasing profits at any expense)?

When building a car you know what markets you want to sell it in so surely, engines would be selected and built knowing full well what variables such as fuel quality etc are in each market. But, in a day and age where manufacturers are fitting fake vents, diffusers, exhausts and god knows what other crap, I guess the term 'a job well done' no longer rests in a quality product but, rather the number of units sold with marketing BS.

It could be, the U.S. uses a different measurement system for rating petrol octane and I know there are different additives in petrol in Amerika compared to the E.U.

More than likely it comes down to a manufacturing tolerance issue which is why MB updated the engines in 2018 and newer model years.

 

[Botus]

Are you suggesting that car manufacturers love a reputation risking slap dash job at the hope of making a quick buck? Ludicrous if so.

these days the accountants did the maths, and reputation is pretty much irrelevant. just give all the money to lewis so he can advertise the brand for you every sunday. so long as the profit comes in higher than the cost of making them all to a reasonable std... that's it job done

after all, nothing's going to stop till the german car industry have finally killed the planet. till then the play station generation are mostly too busy spending everyone else's wages, so they'll never know about build quality. they certainly don't read forums or care why it doesn't run… they're only praying the replacement will come with the interior lights set to another colour, coz they sure can't read enough to find how to change that themselves

 

[Botus]

VAG started fitting chocolate pistons in 2004, I guess Merc moved to the same supplier - they're probably 0.000001p an engine cheaper (so long as only 1% get swapped at warranty, the chocolate pistons probably improve the profit margin....) buy the engines for 2k and sell to 4th year customers at 15k

 

[Sehnsucht Berlin]

VAG started fitting chocolate pistons in 2004, I guess Merc moved to the same supplier - they're probably 0.000001p an engine cheaper (so long as only 1% get swapped at warranty, the chocolate pistons probably improve the profit margin....) buy the engines for 2k and sell to 4th year customers at 15k

Nothing would surprise me. They can make the pistons out of used tampons for all I care, I will never drive another MB.

 

[mioba]

Nothing would surprise me. They can make the pistons out of used tampons for all I care, I will never drive another MB.

What if it was from Heidi Klum.

 

[steveq]

We complain about accountants dictating the quality standards yet allow the extra features and low cost to dominate our car buying decisions.

 

[mioba]

We complain about accountants dictating the quality standards yet allow the extra features and low cost to dominate our car buying decisions.

not only that. you see many people searching for the cheapest parts possible to do repairs.

 

[Sehnsucht Berlin]

What if it was from Heidi Klum.

Nein

 

[Sehnsucht Berlin]

not only that. you see many people searching for the cheapest parts possible to do repairs.

Those sort of car owners is the worst, no matter what trim level of car, some cheap bastard will find a way to band-aid a car with POS parts.

 

[Sehnsucht Berlin]

Almost 1 year since that POS MB threw a rod, I am enjoying my Lexus sedan.