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Wow, thats amazing, can you pls share, some details on what kind of maintaince you are doing on your engine and how many miles it had when you purchased it? thank you!!
I'm at 139,643 at this moment, with no head bolts replaced no records or indication they were done before I bought it back in 2017 when it had 58,535 on it.
Last edited by benzokirk; Dec 30, 2019 at 08:45 PM.
Wow........Your driving that hell out of this E63, 80K in 2 yrs on original head bolts that amazing. I just went over 89K, and mine have been changed out at 87K.
Goes to show everyone that the whole head bolt issue is over exaggerated, in most cases. I feel if the coolant is getting changed out every two years, you can mitigate this whole issue.
That's my personal believe.
i'm now at 140k. had the studs changes and a bunch of other preventative maintenance. has been trouble free for the most part besides the original radiator springing a leak and new factory plastic pulleys failing causing the accessory belt to break the thermostat housing.
thankfully we have sponsors here who make aluminum pulleys.
Explain how changing your coolant, (which is rated for 15 years), will affect the life of the head bolts? I'm curious.
OK, over time the engine coolant degrades. The fluid becomes caustic. If it is left in the radiator for too long a time, it will eventually corrode the metal (radiator and possibly head bolts) and could cause a radiator leak.
I have always kept my engine clean by flushing and replacing your coolant to prevent scale and rust thereby preventing corrosion. This is my opinion, and my practice, that I followed for years and never had a head bolt failure.
Granted, that I just replaced my head bolts a few months ago, but will continue to follow my own preventative practice as my car continues to age.
I know what Mercedes has said about coolant life (15 years), and also about life time tranny fluids. I know that no fluid lasts a lifetime, and coolant does go bad. I know that some members may agree to disagree with me, but that's OK.
Like Hachiroku, I too change mine every two years, as cheap insurance
Honda coolant has had a 10 year 120K mile change interval for over 18 years without any problems. Maybe the 15 year coolant interval on Mercedes is a bit of a stretch because of EU environmental rules, but you don't have proof that it "goes bad".
Coolant is thoroughly lab tested over time for breakdown, etc. You, and anyone that sticks to old 2-3 year coolant changes, in the modern era is living way in the past.
Are you kidding me, the head bolts are in contact with the engine coolant. The design is called a "wet deck" where the head bolts live in coolant and seal the cylinder head with the head bolt's nut flange.
How else could you explain the corrosion that some have seen on their head bolt, including me. I've had five head bolts that showed signs of light corrosion, and one was real iffy.
For those that think that engine coolant last forever, go ahead and follow your logic. I'll stick to my way of thinking. Look at Post #35, those are my old head bolts.
The design is called a "wet deck" where the head bolts live in coolant and seal the cylinder head with the head bolt's nut flange.
For those that think that engine coolant last forever, go ahead and follow your logic. I'll stick to my way of thinking. Look at Post #35, those are my old head bolts.
Where did you get the term "wet deck", related to head bolts running through the water jackets? "Dry deck" is sometimes use in race only engines, were the cooling passages are blocked off to the heads.
Also, where did I say "engine coolant lasts forever". Here is some reading for you.
Engine block deck designs fall into three categories; closed, open and semi-open (a.k.a. semi-closed). In a closed deck design, the deck surface is only drilled for the head fasteners, coolant passages, oil supply and oil drainback passages. The tops of the cylinders are integral with the deck. This configuration is found in all cast-iron blocks and in some high-performance aluminum blocks. Honda’s B-series and a number of other aluminum engines use an open-deck design. These designs have the coolant channel cast into the top of the deck. This design improves cooling and reduces hot spots in the cylinder but provides much less strength and rigidity in the top of the cylinder. When DART built its aftermarket B-series block, they chose a closed-deck design to increase the strength of the block and improve head gasket seal. Today, the majority of aluminum blocks use a semi-open design that attempts to balance the benefits of each design for the intended usage.
Yeah, I do put quite a bit of miles on it, it is my DD in every sense of the phrase. I spent a little time in Germany and observed how they treat their cars, the term Daily Driver isn't even a thing there, its a given, no one puts their car up for the Winter.
After owing the car for two years, I changed the coolant out last year, but I know it was changed the year I bought it. Regular maintenance is LiquiMoly 10W40 in the Summer and 0W40 in the Winter months and try not to go past 3,000 miles. I'm also a big fan of LiquiMoly Engine flush, based on all I've read about it, so I'm about to try that out this weekend. So far I've only experienced valve cover gasket issues and my IM still needs to be replaced. Just waiting on free time to get it done, which I might also tackle this weekend before I get back into the swing of full work weeks again.
Last edited by benzokirk; Jan 2, 2020 at 06:02 PM.
Reason: typos
Where did you get the term "wet deck", related to head bolts running through the water jackets? "Dry deck" is sometimes use in race only engines, were the cooling passages are blocked off to the heads.
Also, where did I say "engine coolant lasts forever". Here is some reading for you.
Engine block deck designs fall into three categories; closed, open and semi-open (a.k.a. semi-closed). In a closed deck design, the deck surface is only drilled for the head fasteners, coolant passages, oil supply and oil drainback passages. The tops of the cylinders are integral with the deck. This configuration is found in all cast-iron blocks and in some high-performance aluminum blocks. Honda’s B-series and a number of other aluminum engines use an open-deck design. These designs have the coolant channel cast into the top of the deck. This design improves cooling and reduces hot spots in the cylinder but provides much less strength and rigidity in the top of the cylinder. When DART built its aftermarket B-series block, they chose a closed-deck design to increase the strength of the block and improve head gasket seal. Today, the majority of aluminum blocks use a semi-open design that attempts to balance the benefits of each design for the intended usage.
You are correct the M156 utilizes a closed deck design, and the E55 uses open deck. But regardless of the term I used, the head bolts are still exposed to coolant. So wouldn’t changing your coolant at a specified interval help mitigate the corrosion that develops on the head bolts. Which was my point from the beginning. By the way which AMG do you own anyway?
Cooling System Myth #1: This system doesn’t need service
One common misconception is that the cooling system is a maintenance-free system. In certain vehicles, when coolant breaks down, it may cause rust and rust particles to become electrically charged. When this happens, the coolant can become highly corrosive. This can result in major damage to the engine and cooling system.
Others believe a vehicle’s coolant does not need to be flushed, but simply topped off. Similar to a car’s oil, coolant breaks down over time. If not serviced, old or broken-down coolant can wear down the engine or cause corrosion. Hence corroded or broken head bolts.
Cooling System Myth #1: This system doesn’t need service
One common misconception is that the cooling system is a maintenance-free system. In certain vehicles, when coolant breaks down, it may cause rust and rust particles to become electrically charged. When this happens, the coolant can become highly corrosive. This can result in major damage to the engine and cooling system.
Others believe a vehicle’s coolant does not need to be flushed, but simply topped off. Similar to a car’s oil, coolant breaks down over time. If not serviced, old or broken-down coolant can wear down the engine or cause corrosion. Hence corroded or broken head bolts.
For someone who is neither an automotive engineer, or experienced service technician, you sure like spreading misleading, and inaccurate information with a perceived authority. Cooling systems being thought of as "maintenance free". How about rust particles theory! Aluminum block, heads, water pump, housings, radiator, etc. Where does all this rust come from? Mercedes updated the head bolts, to eliminate the weak area, that was causing the failures. Notice that nothing was changed regarding the coolant, or replacement interval !
When I have seen cooling system issues, it is more often than not, that the system was tampered with. Typical of body shops, or over zealous owners, prematurely changing out coolant from the factory fill, to a mixture that includes tap water loaded with chlorine, lime, and other minerals, often of the incorrect ratio. Also, when it is replaced, only 40-60% is removed, if relying on just the radiator drain. During service, and repairs, I do check coolant for proper ratio, and electrolysis activity. Also service history. Start showing legitimate factual proof, with empirical data, from actual lab, and engineering studies, rather that your opinions, and here say, from the internet, etc.
Would anybody consider a 200k+ mile E63? I know of one for sale for a very good price. At that mileage, would the head bolts still be the biggest concern? I'd want to verify that they were done already.
when people pull out their factory head studs for updated part numbers there is quite a bit of rust or corrosion. i don't know what the argument is here...engineer this engineer that...TRUE LIFE BRO. highly documented here and on the internet.
you must think any person who is a mechanic at Mercedes is top dog, i think not. Same mechanics glued my valve cover together because they broke it...same with doctors...they're all the same. no, some are drug addicts and only work at x location because they cannot be hired. title doesn't mean one person is smarter or more knowledgeable than anybody else.
Cooling System Myth #1: This system doesn’t need service
One common misconception is that the cooling system is a maintenance-free system. In certain vehicles, when coolant breaks down, it may cause rust and rust particles to become electrically charged. When this happens, the coolant can become highly corrosive. This can result in major damage to the engine and cooling system.
Others believe a vehicle’s coolant does not need to be flushed, but simply topped off. Similar to a car’s oil, coolant breaks down over time. If not serviced, old or broken-down coolant can wear down the engine or cause corrosion. Hence corroded or broken head bolts.
Yuille, is a more definitive source available, such as a coolant or automobile manufacturer's test report?
I have visited my buddy’s shop numerous times and seen several different sets of head bolts, including mine. And they all had the same common dominator......rust. And how do you suppose that, that rust got their. Yes head bolts are stretch to yield bolts, hence their under tension, and yes they sit inside the coolant jacket, and yes AMG installed inferior designed head bolts that some have experienced failures. But not all M156 engines head bolts have failed. But when your engine serial number falls in that range, you listen. I wouldn’t have changed mine, until I was told by an AMG Master Tech that the data shows that most failures have occurred around the 90,000 mile mark, and the likely hood steadily increases with age. So when they tell me, that I should spend a few thousand now, then spend several thousand later if the engine has to come out, I take them at their word. I don’t claim to be an AMG expert, but I do know enough experts and mechanics to heed their advice. Bottom line it’s your car, do what you think is best. But if you were like me an paranoid when you learned about these dam head bolts and changed your engine coolant every two-three years hoping that fresh engine coolant could mitigate the corrosion issue, then good on you. We were of the same mindset.
I replaced my head bolts at 67K miles. The car is 2007 though. I have very extensive service history and coolant hadn't been replaced until 2018 when I bought the car. Here is the video showing their condition. I found just a surface rust on the bolts.
Blue G48 coolant is based on 41 year old tech, that first saw use in VWs for the 1980 model year as G11. It’s one of the first “long life” (5 yr+) coolants ever made.
G48 coolant is silicated, and after a long time those silicates fall out of suspension creating little floating white specks in the system, reducing its ability to clean. If you see a lot of those you should change your coolant out.
When filling you can also substitute G05, the **** yellow nitrated coolant that MB used for the longest time, or upgrade to the modern and highly advanced purple VW G13/G40, a silicated HOAT that is fully compatible with the old blue coolant. Sometimes the mixture turns poop brown, that’s perfectly normal.
Last edited by coupesedan; Apr 26, 2020 at 05:47 PM.
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Slideshow: A one-of-one U.S.-spec Mercedes-Benz SLR McLaren Roadster became even rarer after a factory-backed transformation at McLaren's headquarters.
and also about life time tranny fluids. I know that no fluid lasts a lifetime, and coolant does go bad. I know that some members may agree to disagree with me, but that's OK.
