So I pulled the head off... guess what? *DON'T OPEN IF YOU HAVE A WEAK STOMACH*
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2004 E55,1969 300SEL6.3,2011 ML350 BlueTec Diesel,2005 ML400 CDI
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From: Toronto
V12TT
getting ready for honing and new rings
Uploaded with ImageShack.us
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In order 5 6 7 and broken 8
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Worn ring edge (lower ring above oil scrapper)
All 4 look like this.
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Number 6 failed land rings and number 8 failed land rings + surface.
(8 on left, old 6 on right)
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Poor thing... is really having a bad life
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Uploaded with ImageShack.us
Uploaded with ImageShack.us
In order 5 6 7 and broken 8
Uploaded with ImageShack.us
Worn ring edge (lower ring above oil scrapper)
All 4 look like this.
Uploaded with ImageShack.us
Number 6 failed land rings and number 8 failed land rings + surface.
(8 on left, old 6 on right)
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Poor thing... is really having a bad life
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Last edited by benz_addict; May 19, 2011 at 01:56 AM.
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V12TT
on the clock it's close to 236,500 KMS
Modded from 170,000KMS
With 180 Pulley from 230,000 KMS
2003 model
Yup all after number 6 cyl had failed ring lands
Stock rail, stock injectors, stock pump, OEM filter
No?
I wouldn't say so, Eurocharge has been very helpful
I hope for the best for your car! I hope no one goes through this. Do not own this car without warranty
Yeah man I hope these problems stop. What's scaring me are these 2003 models with really weak landing rings, especially number 8.
Getting head reconditioned
EC550 injectors
DIY
Ah, worse things in life man. Just a car and nothing two hands and knowledge can't fix. And of course alot of $$
16 grand? 
Sleeve looks fine. But couple cylinders have scratches that need to be slightly honed out.
Sulfur in gasoline kills the nikasil walls. I always run OCT 94 min with no or low sulfer.
I think the walls are good they just need to be slightly honed they feel, look good but I need to measure them before honing and if needed a slight even hone to smooth everything out.
It's a mystery to me. Timing is on fine. I confirmed it before pulling the heads with CP set to 40 TDC and cams tools locked in place.
Thanks, I love your CLS man
Are you using the same type low compression pistons with the dip on the surface? Any pics and more info on the forged pistons your using?
I'm thinking of swapping them all out while I'm at it.
I think it's something to do with fuel supply and running lean and way too hot. As everybody knows these 55k motors have massive heat soak problems.
Fuel delivery. I need to verify my tune.
+1
Thanks! I'll keep you guys updated
Cyl 6 piston failed last year... so just replaced it from an 05 E55
Thanks
I think it's more due to heat and lack of fuel running to lean and hot problem
I'm running catless and honestly can't find any pieces except when I took the head bolt out there seemed to be some pieces in there? 
I think the piece tried to escape through the exhaust while it was closing and bent the valve then? I can't see any impact marks on the valve or piston.
You were dead on
Modded from 170,000KMS
With 180 Pulley from 230,000 KMS
2003 model
Yup all after number 6 cyl had failed ring lands
Stock rail, stock injectors, stock pump, OEM filter
No?
I wouldn't say so, Eurocharge has been very helpful
Getting head reconditioned
DIY
Ah, worse things in life man. Just a car and nothing two hands and knowledge can't fix. And of course alot of $$
Sulfur in gasoline kills the nikasil walls. I always run OCT 94 min with no or low sulfer.
I have never seen the top of a piston break off like that before. I have blown a few ring lands off but not the top land. I have seen the top land burn off after ring failure but your ring still looks intact. Hope the cylinder wall is ok. If not sleeve it and go with custom pistons.
Thanks, I love your CLS man
Sorry to see this, I've just been through the same ordeal (only my piston damage was to the skirt).
I decided to rebuild the engine. We used forged pistons and modified the fuel rail. The car's been running great ever since and actually feels more responsive than before (possibly because the new pistons are lighter than the stockers).
Don't sweat it too much, its not as bad as it seems.
When it first happened I thought it was the end of the world. Looking back, it was just another hurdle.
I decided to rebuild the engine. We used forged pistons and modified the fuel rail. The car's been running great ever since and actually feels more responsive than before (possibly because the new pistons are lighter than the stockers).
Don't sweat it too much, its not as bad as it seems.
When it first happened I thought it was the end of the world. Looking back, it was just another hurdle.
I'm thinking of swapping them all out while I'm at it.
That is absolutely a fueling AND/OR ignition timing problem. I've seen this kind of damage a million times from knock. Since it was number 8 and people here seem to normally pop number 8, than I can assume that the problem is fueling over timing. But that is not a failure that occurred just because the part was defective or something like that.
Agreed. jumpinjack it's most likely caused the inferior design of the stock fuel rails not being able to deliver fuel to the #8 cylinder causing a lean mixture. not usually a big problem on stock cars, but on modded cars running higher boost it definately comes into play as the OP did note that he was doing a number of WOT pulls.
Ok i could be wrong but it just looks like too clean of a brake, it just doesn't look like any other number 8 piston failures I've ever seen on these motors, didn't benz_addict just replace this piston with a used one ?? was piston to bore clearance checked when the motor was reassembled,
Oh Ouch, don't worry it can be fixed, chin up.
I would replace the head though, warped aluminum heads after a thermal and mechanical (fod) event, even resurfaced never stop warping, you should be able to find a good used one. Head bolts and threads in block need to be checked before replacement head gets torqued.
From what I see your cylinder looks serviceable, I think you may have lucked out.
for those that have not read the Head thread,
https://mbworld.org/forums/w211-amg/...pped-head.html
I would replace the head though, warped aluminum heads after a thermal and mechanical (fod) event, even resurfaced never stop warping, you should be able to find a good used one. Head bolts and threads in block need to be checked before replacement head gets torqued.
From what I see your cylinder looks serviceable, I think you may have lucked out.
for those that have not read the Head thread,
https://mbworld.org/forums/w211-amg/...pped-head.html
Last edited by benz_addict; May 19, 2011 at 01:53 AM.
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From: Toronto
V12TT
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From: Toronto
CLS63 PP
Bad news, but could definately be worse. I always love your dedicatation to solving this stuff with a great attitude and hard work. LEt me know if you need anything man.
Are you planning on honing the block in the enginebay with a drill hone? Be careful to use lots of lube( wd 40 or proper honing lube) Make sure its good and mounted centered and square to avoid taking the cyl out of round.
Pete
Are you planning on honing the block in the enginebay with a drill hone? Be careful to use lots of lube( wd 40 or proper honing lube) Make sure its good and mounted centered and square to avoid taking the cyl out of round.
Pete
Last edited by KLR CLS; May 19, 2011 at 09:36 AM.
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From: Toronto
V12TT
Bad news, but could definately be worse. I always love your dedicatation to solving this stuff with a great attitude and hard work. LEt me know if you need anything man.
Are you planning on honing the block in the enginebay with a drill hone? Be careful to use lots of lube( wd 40 or proper honing lube) Make sure its good and mounted centered and square to avoid taking the cyl out of round.
Pete
Are you planning on honing the block in the enginebay with a drill hone? Be careful to use lots of lube( wd 40 or proper honing lube) Make sure its good and mounted centered and square to avoid taking the cyl out of round.
Pete
Let me know if your going to install cams I got the tools if you want them
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From: London, UK
No longer stock '06 E55, A3 3.2 Quattro, GLE 400d, R107 280SL, Golf Polo
wow... thats pretty good milage for a modded motor!
Looks more than a #8 fuel starvation issue to me and could also be mechanical fatigue in combination with a general lean condition.
Have you checked your fuel pressure? With that mialage I expect your fuel filter may a tad blocked compromising fuel pressure.
In the end it can be fixed though!
EDIT: given the failures i'd go new forged pistons all round now ... how the conrods and rest of bottom end?
Looks more than a #8 fuel starvation issue to me and could also be mechanical fatigue in combination with a general lean condition.
Have you checked your fuel pressure? With that mialage I expect your fuel filter may a tad blocked compromising fuel pressure.
In the end it can be fixed though!
EDIT: given the failures i'd go new forged pistons all round now ... how the conrods and rest of bottom end?
Last edited by stevebez; May 20, 2011 at 04:30 AM.
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V12TT
This project is on a hold for a little bit as I have to wait for parts to arrive. Mainly from Germany directly to my dealership. I hope it'll be fast.
BTW if anyone's wondering there's a new part number for the rings that will fit the stock piston after a fine hone. They call it the repair ring set or something not sure..
BTW if anyone's wondering there's a new part number for the rings that will fit the stock piston after a fine hone. They call it the repair ring set or something not sure..
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V12TT
Thanks viper.
Got the new rings today installed them on the other 3 pistons and put them back in. Just waiting for 1 piston to arrive to finish off my work. Did the rod bearings and new oil pan gasket. Some oil leak was present from the oil level sensor but I think it's a common problem with all 55k's.
Until then It's still puzzling me how the valve got bent and how the surface of the piston broke... FYI this happened after 3 or 4 WOT, under WOT. I'm thinking it over revved with heat and fuel starvation to number 8 as the issue.
Got the new rings today installed them on the other 3 pistons and put them back in. Just waiting for 1 piston to arrive to finish off my work. Did the rod bearings and new oil pan gasket. Some oil leak was present from the oil level sensor but I think it's a common problem with all 55k's.
Until then It's still puzzling me how the valve got bent and how the surface of the piston broke... FYI this happened after 3 or 4 WOT, under WOT. I'm thinking it over revved with heat and fuel starvation to number 8 as the issue.
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V12TT
Building process (thanks shardul for the piston!)
Pistons cleaned up and installed in correct postion (arrow facing towards front of engine)
Head, surfaced cleaned and checked for warpage.
Valve seals replaced.
Cylinder 8 exhaust valve replaced.
All cleaned up.
Head installed and torqued to correct sequence.
Notice the cam timing tool installed.
These will hold the cam in correct position while crank is at 40* A-TDC
The f-ing chain tensioner is located behind the alternator and is a ***** to get to and losen up.
Cam tool installed on right side (rocker bridge losened up)
Timing is perfect!
Arrows point to copper markings.
Rocker bridge new bolts and installed.
Everything else bolted back up and re-checked. Ready for starting the engine...
Pistons cleaned up and installed in correct postion (arrow facing towards front of engine)
Head, surfaced cleaned and checked for warpage.
Valve seals replaced.
Cylinder 8 exhaust valve replaced.
All cleaned up.
Head installed and torqued to correct sequence.
Notice the cam timing tool installed.
These will hold the cam in correct position while crank is at 40* A-TDC
The f-ing chain tensioner is located behind the alternator and is a ***** to get to and losen up.
Cam tool installed on right side (rocker bridge losened up)
Timing is perfect!
Arrows point to copper markings.
Rocker bridge new bolts and installed.
Everything else bolted back up and re-checked. Ready for starting the engine...
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V12TT
Drove it approx 50kms right now, everything seems good so far. No rough idle, no problems no hesitations no noises. Running with no supercharger belt right now so the secondary TB is open as main air flow as I have to carefully break in the engine and not take it past 3500k RPMS for 2000KMS.
VIDEO: http://www.youtube.com/watch?v=V0padcZbYzE
VIDEO: http://www.youtube.com/watch?v=V0padcZbYzE
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2017 991.2 Turbo PDK 2017 C63S Coupe Ceramic Brakes 2015 CLS63S AMG Full House
Yes, indeed, and our local (so-called) Eurocharged agents in South Africa, have to be the most evasive tuning shop here. I don't know if this is any coincidence, but when I called them 4 months ago for doing an upgrade on my 05 immaculate Obsidian E55 W211, they actually said that they currently do not offer any upgrades for any of the 55 Komp motors? No Conspiracy stories here. So I did not walk away, I just walked away real quick and was glad nothing ever came of it.
I send all 12 of my most loved AMG's to AMG-SA, they a special group that takes care of all my desires to them Beasts.
I'm just such a busy man gotta show you gentleman images, runs for fun only and just how passionate this whole W211 E55 Komp E-Class, got hold of my soul.
Good Luck with cyl 8, and also this from a good friend and Serious AMG collector, from Dusseldorf, he tells me that some of the best ever 55Komp motors were built 09/12/02 through to 2003, but anyway.
So I did not walk away, I just walked away real quick and was glad nothing ever came of it.I send all 12 of my most loved AMG's to AMG-SA, they a special group that takes care of all my desires to them Beasts.
I'm just such a busy man gotta show you gentleman images, runs for fun only and just how passionate this whole W211 E55 Komp E-Class, got hold of my soul.
Good Luck with cyl 8, and also this from a good friend and Serious AMG collector, from Dusseldorf, he tells me that some of the best ever 55Komp motors were built 09/12/02 through to 2003, but anyway.
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2017 991.2 Turbo PDK 2017 C63S Coupe Ceramic Brakes 2015 CLS63S AMG Full House
Well Done, Benz Addict, and all you great guys on this forum, wish we had such a great passion of AMG, here in South Africa.
You guys are great, much respect to all of you.
You guys are great, much respect to all of you.
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CLS63 PP
Yes, indeed, and our local (so-called) Eurocharged agents in South Africa, have to be the most evasive tuning shop here. I don't know if this is any coincidence, but when I called them 4 months ago for doing an upgrade on my 05 immaculate Obsidian E55 W211, they actually said that they currently do not offer any upgrades for any of the 55 Komp motors? No Conspiracy stories here. So I did not walk away, I just walked away real quick and was glad nothing ever came of it.
I send all 12 of my most loved AMG's to AMG-SA, they a special group that takes care of all my desires to them Beasts.
I'm just such a busy man gotta show you gentleman images, runs for fun only and just how passionate this whole W211 E55 Komp E-Class, got hold of my soul.
Good Luck with cyl 8, and also this from a good friend and Serious AMG collector, from Dusseldorf, he tells me that some of the best ever 55Komp motors were built 09/12/02 through to 2003, but anyway.
So I did not walk away, I just walked away real quick and was glad nothing ever came of it.I send all 12 of my most loved AMG's to AMG-SA, they a special group that takes care of all my desires to them Beasts.
I'm just such a busy man gotta show you gentleman images, runs for fun only and just how passionate this whole W211 E55 Komp E-Class, got hold of my soul.
Good Luck with cyl 8, and also this from a good friend and Serious AMG collector, from Dusseldorf, he tells me that some of the best ever 55Komp motors were built 09/12/02 through to 2003, but anyway.
This has nothing to do with Eurocharged and on the contrary they have gone WAAAAY above and beyond anything I have ever seen to help out Salik.
Salik's car is a high mileage, highly abused car which had a no name local tune on it. He also ran a pulley with no tune on it for some time.
When he popped the #6 piston, EC offered him a FREE Piston and a FREE tune to help him out. Jake and Jerry where just helping a guy out for no benefit to themselves.
I say it time and time again, they only person to blame for damage to a modded car is yourself.
People looking for Drama on this board need to get a more active social life...
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2017 991.2 Turbo PDK 2017 C63S Coupe Ceramic Brakes 2015 CLS63S AMG Full House
This has nothing to do with Eurocharged and on the contrary they have gone WAAAAY above and beyond anything I have ever seen to help out Salik.
Salik's car is a high mileage, highly abused car which had a no name local tune on it. He also ran a pulley with no tune on it for some time.
When he popped the #6 piston, EC offered him a FREE Piston and a FREE tune to help him out. Jake and Jerry where just helping a guy out for no benefit to themselves.
I say it time and time again, they only person to blame for damage to a modded car is yourself.
People looking for Drama on this board need to get a more active social life...
Salik's car is a high mileage, highly abused car which had a no name local tune on it. He also ran a pulley with no tune on it for some time.
When he popped the #6 piston, EC offered him a FREE Piston and a FREE tune to help him out. Jake and Jerry where just helping a guy out for no benefit to themselves.
I say it time and time again, they only person to blame for damage to a modded car is yourself.
People looking for Drama on this board need to get a more active social life...
they were not willing to or instead and I quote them saying, that they do not do any upgrades for 55 Kompressor motors in South Africa.
