M156 head bolt problems
07-06-2012, 04:10 PM
#76
A few posters have commented of low coolant levels and the consensus here seems to advise a visit to the dealer to check it out to be on the safe side. I had this information saved for general purposes (note that it refers to diesel engines) but it's a good read nonetheless.
Glycol
Glycol enters diesel engine motor oils as a result of defective seals, blown head gaskets, cracked cylinder heads, corrosion damage and cavitation. One study found glycol in 8.6 percent of 100,000 diesel engine samples tested. A separate study of 11,000 long-haul trucks found severe levels of glycol in 1.5 percent of samples and minor amounts of glycol in 16 percent of samples. The following are some of the risks associated with glycol contamination:
Just 0.4 percent coolant containing glycol in diesel engine oil is enough to coagulate soot and cause a dump-out condition leading to sludge, deposits, oil flow restrictions and filter blockage.
According to one study, glycol contamination results in wear rates 10 times greater than water contamination alone.
Glycol reacts with oil additives causing precipitation. For instance, an important antiwear additive in motor oils, zinc dialkyl dithiophosphate (ZDDP), will form reaction products and plug filters when oil is contaminated with glycol. This leads to loss of antiwear and antioxidant performance as well.
Glycol has led to cold seizure of engines.
Ethylene glycol oxidizes into corrosive acids, including the following: glycolic acid, oxalic acid, formic acid and carbonic acid. These acids cause a rapid drop in the oil's alkalinity (base number), resulting in an unprotected corrosive environment and base oil oxidation.
Oil ***** (abrasive spherical contaminants) form from the reaction of calcium sulfonate detergent additives (found in nearly all motor oils) and glycol contamination. These ***** are a known cause of damage to crankcase bearings and other frictional surfaces within an engine.
Glycol contamination substantially increases oil viscosity which impairs lubrication and oil cooling.
Glycol
Glycol enters diesel engine motor oils as a result of defective seals, blown head gaskets, cracked cylinder heads, corrosion damage and cavitation. One study found glycol in 8.6 percent of 100,000 diesel engine samples tested. A separate study of 11,000 long-haul trucks found severe levels of glycol in 1.5 percent of samples and minor amounts of glycol in 16 percent of samples. The following are some of the risks associated with glycol contamination:
Just 0.4 percent coolant containing glycol in diesel engine oil is enough to coagulate soot and cause a dump-out condition leading to sludge, deposits, oil flow restrictions and filter blockage.
According to one study, glycol contamination results in wear rates 10 times greater than water contamination alone.
Glycol reacts with oil additives causing precipitation. For instance, an important antiwear additive in motor oils, zinc dialkyl dithiophosphate (ZDDP), will form reaction products and plug filters when oil is contaminated with glycol. This leads to loss of antiwear and antioxidant performance as well.
Glycol has led to cold seizure of engines.
Ethylene glycol oxidizes into corrosive acids, including the following: glycolic acid, oxalic acid, formic acid and carbonic acid. These acids cause a rapid drop in the oil's alkalinity (base number), resulting in an unprotected corrosive environment and base oil oxidation.
Oil ***** (abrasive spherical contaminants) form from the reaction of calcium sulfonate detergent additives (found in nearly all motor oils) and glycol contamination. These ***** are a known cause of damage to crankcase bearings and other frictional surfaces within an engine.
Glycol contamination substantially increases oil viscosity which impairs lubrication and oil cooling.
07-06-2012, 08:44 PM
#77
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Porsche 991S, Cayenne S, 1972 BMW 3.0CS E9 Coupe
Re: glycol in motor oil.
This is one reason why people should consider doing UOAs not only at their scheduled OCIs but also as sampling once in a while between OCIs. Glycol will be detected in a UOA. I did UOAs all the time with my previous AMG (and still do with all my current cars.) It's only $25 a pop. And with the M156, you also want to keep an eye on the Fe numbers and other metals, too. That will help you monitor any potentially excessive cam wear and lifter issues. UOAs are very valuable and imho should be part of any performance car ownership.
And I've said this before and I'll say it once again:
It's important to have a good relationship with your dealership and your SA. I've purchased my cars from the same dealer even though once in a while they might not have been able to exactly match a deal from another dealership. But even paying up to $1k over a discount sale price from elsewhere just to stay with your dealership can pay back big dividends in loyalty treatment. Buying a car is one thing, but servicing that car over the long run is key.
Case in point: before I sold my E63, my SA knew of the TSB for the low coolant CEL and head bolt issue. My engine # was in the range. His response was "right before your warranty is up you'll get a low coolant CEL and then we'll proceed to replace the head bolts."
I hinted at this before without being explicit but there you go, that's explicit as it gets. My dealership was willing to upgrade the head bolts for me before my factory warranty was up. And they even knew that I had a MBUSA extended warranty that I had purchased from them, but wanted to get it "fixed" before the original factory warranty was up.
So again, stay tight with your dealership and your SA (gifts during the holidays are always a good thing too.) It's kind of a necessary symbiotic relationship that can be important with cars like these where any repair is very pricey. Plus you'll need an advocate on your side if it ever comes time to shove.
And this is not to say that MBUSA shouldn't be stepping up to the plate themselves and fess up to their defects. They definitely should but we all know they won't unless forced. In the meantime owners need to always cover all their bases and try to be as proactive as necessary.
This is one reason why people should consider doing UOAs not only at their scheduled OCIs but also as sampling once in a while between OCIs. Glycol will be detected in a UOA. I did UOAs all the time with my previous AMG (and still do with all my current cars.) It's only $25 a pop. And with the M156, you also want to keep an eye on the Fe numbers and other metals, too. That will help you monitor any potentially excessive cam wear and lifter issues. UOAs are very valuable and imho should be part of any performance car ownership.
And I've said this before and I'll say it once again:
It's important to have a good relationship with your dealership and your SA. I've purchased my cars from the same dealer even though once in a while they might not have been able to exactly match a deal from another dealership. But even paying up to $1k over a discount sale price from elsewhere just to stay with your dealership can pay back big dividends in loyalty treatment. Buying a car is one thing, but servicing that car over the long run is key.
Case in point: before I sold my E63, my SA knew of the TSB for the low coolant CEL and head bolt issue. My engine # was in the range. His response was "right before your warranty is up you'll get a low coolant CEL and then we'll proceed to replace the head bolts."
I hinted at this before without being explicit but there you go, that's explicit as it gets. My dealership was willing to upgrade the head bolts for me before my factory warranty was up. And they even knew that I had a MBUSA extended warranty that I had purchased from them, but wanted to get it "fixed" before the original factory warranty was up.
So again, stay tight with your dealership and your SA (gifts during the holidays are always a good thing too.) It's kind of a necessary symbiotic relationship that can be important with cars like these where any repair is very pricey. Plus you'll need an advocate on your side if it ever comes time to shove.
And this is not to say that MBUSA shouldn't be stepping up to the plate themselves and fess up to their defects. They definitely should but we all know they won't unless forced. In the meantime owners need to always cover all their bases and try to be as proactive as necessary.
07-07-2012, 06:25 AM
#78
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C63, 335i
^Very well said there.
I currently have an early production 09 C63 so I'm fairly sure my car has the old design.
I brought up the issue with the SA and had their chief mechanic assure me that should this ever happen to my car, they were confident that Mercedes would pick up 100% of the cost even if I was to be out of warranty. He also mentioned that most fail around 30,000 miles and if I were to make it past that, then there most likely won't be a problem in the future.
However, I'm not entirely convinced based on some of the accounts I've read so far on this forum and the fact the dealership has only done 1 headbolt replacement so far on another AMG at 26,000 miles.
I bought the car CPO and still have a little over a year left on my warranty. Sitting at about 35,000 miles right now, would you guys think the problem could present itself sometime before my warranty is up or should I force the issue with my SA.
I currently have an early production 09 C63 so I'm fairly sure my car has the old design.
I brought up the issue with the SA and had their chief mechanic assure me that should this ever happen to my car, they were confident that Mercedes would pick up 100% of the cost even if I was to be out of warranty. He also mentioned that most fail around 30,000 miles and if I were to make it past that, then there most likely won't be a problem in the future.
However, I'm not entirely convinced based on some of the accounts I've read so far on this forum and the fact the dealership has only done 1 headbolt replacement so far on another AMG at 26,000 miles.
I bought the car CPO and still have a little over a year left on my warranty. Sitting at about 35,000 miles right now, would you guys think the problem could present itself sometime before my warranty is up or should I force the issue with my SA.
07-08-2012, 02:39 PM
#80
07-09-2012, 04:57 PM
#81
MBWorld Fanatic!
^Very well said there.
I currently have an early production 09 C63 so I'm fairly sure my car has the old design.
I brought up the issue with the SA and had their chief mechanic assure me that should this ever happen to my car, they were confident that Mercedes would pick up 100% of the cost even if I was to be out of warranty. He also mentioned that most fail around 30,000 miles and if I were to make it past that, then there most likely won't be a problem in the future.
However, I'm not entirely convinced based on some of the accounts I've read so far on this forum and the fact the dealership has only done 1 headbolt replacement so far on another AMG at 26,000 miles.
I bought the car CPO and still have a little over a year left on my warranty. Sitting at about 35,000 miles right now, would you guys think the problem could present itself sometime before my warranty is up or should I force the issue with my SA.
I currently have an early production 09 C63 so I'm fairly sure my car has the old design.
I brought up the issue with the SA and had their chief mechanic assure me that should this ever happen to my car, they were confident that Mercedes would pick up 100% of the cost even if I was to be out of warranty. He also mentioned that most fail around 30,000 miles and if I were to make it past that, then there most likely won't be a problem in the future.
However, I'm not entirely convinced based on some of the accounts I've read so far on this forum and the fact the dealership has only done 1 headbolt replacement so far on another AMG at 26,000 miles.
I bought the car CPO and still have a little over a year left on my warranty. Sitting at about 35,000 miles right now, would you guys think the problem could present itself sometime before my warranty is up or should I force the issue with my SA.
07-09-2012, 05:00 PM
#82
MBWorld Fanatic!
ive been trying to call the former dealership for days. not surprisingly, no one is getting back to me. lol. but what you say makes sense ... since MB factory stopped using the old bolts in mid 2010, i suppose we can assume that dealerships would have also stopped using the old bolts around that time, and at least by mid 2011 (which is when the repair was done). but who really knows? 
07-12-2012, 12:15 AM
#83
An FYI here. I was told by someone within the MB organization that head bolt failures occur across all AMG models that use the M156 engine. My theory as to why we don't hear about them so much is that those owners are generally a wealthier demographic that doesn't spend nearly as much time following or posting about this issue on forums like MB World.
07-12-2012, 02:32 AM
#84
MBWorld Fanatic!
An FYI here. I was told by someone within the MB organization that head bolt failures occur across all AMG models that use the M156 engine. My theory as to why we don't hear about them so much is that those owners are generally a wealthier demographic that doesn't spend nearly as much time following or posting about this issue on forums like MB World.
07-16-2012, 02:55 AM
#85
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07-16-2012, 07:01 AM
#86
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CLK63 Black, E350 Wagon, Supercharged Denali, Lotus Elise, Tesla Model 3 Dual-Motor.
The head bolt concern will be much more of a concern for anyone installing a supercharger. Forced induction helps to separate the heads from the block. Its standard practice to up grade to ARP Head Bolt when bumping the Horse Power on EVO's.
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07-18-2012, 10:53 PM
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2010 C63 AMG
This thread was super helpful. Thank you all.
I'll create a formal introduction thread soon, but I've been in the market for a 2009 (or 2010 if the price is right) C63 AMG and have been aggressively searching. Found one at CarMax (so not MB CPO) and was about to pull the trigger on it when I discovered that by the time I become the registered owner, the factory warranty would've expired (expires in 2 days) and that would make me ineligible for the MB ELW. This thread really gave me cause for concern, and was the basis of my decision to not get a car that would no longer be eligible for the ELW.
I'll create a formal introduction thread soon, but I've been in the market for a 2009 (or 2010 if the price is right) C63 AMG and have been aggressively searching. Found one at CarMax (so not MB CPO) and was about to pull the trigger on it when I discovered that by the time I become the registered owner, the factory warranty would've expired (expires in 2 days) and that would make me ineligible for the MB ELW. This thread really gave me cause for concern, and was the basis of my decision to not get a car that would no longer be eligible for the ELW.
07-22-2012, 05:35 PM
#89
I dont want to scare you but that puff of white smoke would concern me. Check your coolant level....if its low and you have no leak, most likely its the coolant slowly seeping into to your engine. If you are sure that you did indeed grab the gear and it didnt shift, it might have been geeting ready to go into limp mode, which is exactly what happened to me. I just recieved my car back this week for the headbolt issue. I was fortunate to be in the original manufacturers warranty and the whole bill was picked up by MB. A month without your car in the summer hurts, but they did a great job, and the car feels great. I got piece of mind now that the issue has been dealt with.
07-25-2012, 02:27 AM
#90
Member
Watch this Space
Apparently due to the cost of my repair (the dealer said $35K 
) it has gone to the Managing Director of MB Australia to make the call tomorrow as to if they will contribute to the repair.
Bruce
) it has gone to the Managing Director of MB Australia to make the call tomorrow as to if they will contribute to the repair.Bruce
07-25-2012, 09:03 AM
#91
MBWorld Fanatic!
07-25-2012, 04:12 PM
#92
Here's my prediction: If MB AUS steps up, "does the right thing" and covers 100% of the repair bill, M156 owners in your shoes have legal standing to be compensated for some measure of breach of warranty. And MB AUS would know this. That's why I put "does the right thing" in quotes. Because they wouldn't be doing it for some non-contractual-related ethical consideration; it would be because owners in your shoes may have legal rights that can be protected.
07-26-2012, 03:46 AM
#93
It will be EXTREMELY difficult for MB to implement a uniform (policy) repair program for out of warranty head bolt cases. So many variables to consider...year of production, mileage, modifications performed if any, differing consumer protection laws and attitudes from country to country, even state to state, value of the customer to the company...you name it. And then there is the overarching AMG brand consideration. They truly are caught between that proverbial rock and a hard place. It may well be manageable to deal with these on a low-key case-by-case basis if failures remain a small percentage of M156's out there but I expect to see a higher percentage of failures in 2013 and beyond as '08 and '09 pile up the mileage and cycle out of warranty.
07-26-2012, 01:39 PM
#94
MBWorld Fanatic!
I believe the number is also stamped onto the crank case. However, that area between the engine and firewall is really difficult to see. I think I will just ask the MB service for the number during my A service in a few months.
07-26-2012, 03:03 PM
#95
It will be EXTREMELY difficult for MB to implement a uniform (policy) repair program for out of warranty head bolt cases. So many variables to consider...year of production, mileage, modifications performed if any, differing consumer protection laws and attitudes from country to country, even state to state, value of the customer to the company...you name it. And then there is the overarching AMG brand consideration. They truly are caught between that proverbial rock and a hard place. It may well be manageable to deal with these on a low-key case-by-case basis if failures remain a small percentage of M156's out there but I expect to see a higher percentage of failures in 2013 and beyond as '08 and '09 pile up the mileage and cycle out of warranty.
When vehicles are modified, that shouldn't necessarily kill the consumers' rights. But, in practice, if this type of dispute made it's way to trial, it would be anyone's guess whether a jury would disregard MB/AMG's expert that would undoubtedly testify that any modifications can cause premature engine damage. And unless this became a class action, these cases would need to be litigated on an individual basis, and every jury is different. Although, I would bet most jurors are not car enthusiasts and would not have much patience for the rights of aftermarket enthusiasts.
07-26-2012, 03:32 PM
#96
I don't foresee any type of uniform policy for this issue. The way I view this situation, if you are out of warranty, have not mods, performed regular scheduled service, but a defect existed in the engine during the express warranty period (a defect that doesn't present itself in a consistent and recognizable manner), and MB has not swiftly and expressly denied contribution for repair of the head bolt issue, there must be some reason that supports the rights of the vehicle owner. What the reason is, I don't know? It could be some type of implied warranty basis.
When vehicles are modified, that shouldn't necessarily kill the consumers' rights. But, in practice, if this type of dispute made it's way to trial, it would be anyone's guess whether a jury would disregard MB/AMG's expert that would undoubtedly testify that any modifications can cause premature engine damage. And unless this became a class action, these cases would need to be litigated on an individual basis, and every jury is different. Although, I would bet most jurors are not car enthusiasts and would not have much patience for the rights of aftermarket enthusiasts.
When vehicles are modified, that shouldn't necessarily kill the consumers' rights. But, in practice, if this type of dispute made it's way to trial, it would be anyone's guess whether a jury would disregard MB/AMG's expert that would undoubtedly testify that any modifications can cause premature engine damage. And unless this became a class action, these cases would need to be litigated on an individual basis, and every jury is different. Although, I would bet most jurors are not car enthusiasts and would not have much patience for the rights of aftermarket enthusiasts.
07-26-2012, 05:45 PM
#97
Well said. It's definitely worth looking into.
07-26-2012, 08:48 PM
#98
Member
MB Contributes
Finally I have a response from MB Australia. They have offered to buy all the new parts and rebuild the motor at their cost. I am to pay for the motor installation and testing up to A$ 5K. The Dealer I spoke to was quite aplogetic about the time taken to make this offer and said this was part of the reason for the offer being generous. He expects my contribution will be less than 5K.
There are cases for more MB contribution and some for less however overall I am satisfied with this. Now to get the car fixed and back on the road. It will still take aboot another 4 weeks to get all the parts, rebuild and test.
My co-contribution will result in a 12 month warranty on the engine.
There are cases for more MB contribution and some for less however overall I am satisfied with this. Now to get the car fixed and back on the road. It will still take aboot another 4 weeks to get all the parts, rebuild and test.
My co-contribution will result in a 12 month warranty on the engine.
07-26-2012, 09:02 PM
#99
Congrats Bruce...it is settled! Everyone will have their own thoughts on this but IMO you made out fine considering the amount of work to be done and parts required. So now we have a benchmark going forward too...
