CSIKTY3

My car has 37,000 miles. I was well aware this would happen but not so soon! I did buy the platinum highest and most expensive warranty but it is not factory warranty. It is from Fidelity which I have heard nothing but good things for high line luxury cars.

Has anyone had any experience with aftermarket extended warranty companies and the head bolt issue?

I spoke with the warranty company and they are requesting a tear down of the engine as the Dealer thinks its the head bolts but doesn't have solid proof just yet. If the warranty company denies the claim I must pay all labor for tear down at min to get my car back.. they want my approval for the tear down, any feedback?

Ingenieur

GSo it's not headbolts?

There were over 60,000 m156's produced in the affected range
I can't find 10 DOCUMENTED failures, most on tuned cars
0 on euro or UK sites

Audi/VW is having an issue with the 2 liter turbo motor oil consumption
Iirc there is a suit and settlement?
Anyways, in their research the noted it wasn't happening in europe
After looking at ecu's, service records, etc. they determined it was correlated to break in method: closely observed in europe, pretty much disregarded in the US
It was the rings weren't seated properly
One main reason for breaking it in properly
More than a few post on here saying 'drive it like you stole it' off the lot

Could it be the same for headbolts?
If the bolts were gradually 'excercised' or worked during break in does it increase their strength?
Rather than shocking them
Gradually working metal before loading does make it stronger in the long run

rentzington

Sucks to hear, makes me reconsider the third party warranty i got...still debating canceling and spending 2x the price for mbefw

Hope they pay your claim, but I personally wouldnt want a total tear down of a hand built engine if the dealer thinks it's head bolts

aussie e55

sorry to hear of your problem what parts are covered engine wise by your warranty & max. $ payable.

Ingenieur

Does it meet the conditions/symptoms on the TSB?
Did they pressurize the cooling system and look for coolant in the cylinder?
Did they pressurize the cylinder and look for bubbles in the expansion tank?
Cross check coolant for oil and oil for coolaant?

It would seem tear down would't be bad
Remove the cams and see if a bolt spins
If it is a bolt will they pay for the tesr down since that must be done for the repair?
Or you only pay if not a bolt?
Might as well replace them if you go that far
Seek goodwill from MB

Merc63

Complete tear down is so stupid.

Do a pressure test. Check oil for coolant like our local engineer said.

If those fail. Remove the engine and pull the heads. Tearing down the bottom end is completely pointless.

YellowJacket

Fidelity was no good with me. Had stuck injector failure on my first C63, and they only footed about 1/3 of the bill ,and I had the highest rated package. It was a miserable experience. They have their own standards to repair, and if the AMG standards are higher or require additional testing or parts, they only cover the bare parts. Then of course Mercedes says if they don't do the full AMG recommended repair and testing, then their work is not warranted.

I paid and moved on, and vowed never to use an aftermarket warranty again!

CPD SLK

Can you PM me info on your warranty? I looked around for so long, but nobody would warranty an AMG in california and I was past the OEM warranty, so I couldn't get that extended

604 C63

Then you aint lookin that hard.

average joe

I am in UK and know of a few head bolt failures, just in dealer yesterday picking parts up and they had a ML63 in with a snapped head bolt.

There are probably loads more failures but people don't report it on forums....they just take it to dealer and get given a nice courtesy car while there car is fixed. Minimum disruption so therefore no need for them to shout from the rooftops.

Merc63

There was 3 or 4 here already. City of 1million.

Why even waste money on warranty. Get the bolts replaced one at a time with studs or upgraded mb bolts and be done with it if your worried. Good seling feature too.

rentzington

one thing i was told when i bought my c63 recently is fidelity doesn't cover AMG anymore, guy said they used to have several third party companies and they all dropped amg except for easycare (carchex does too but they dont use them)

I'm assuming they ended up upside down on too many amg warranties

solekeeper

aftermarket warranties blow.

only 37k miles on the car and these are gone? that is no bueno. good luck on the fix!

shardul

iTrader: (1)

lot of aftermarket warranty companies are not accepting new contracts to cover AMG cars any more

AMG6.3

Sorry to hear about your car, that stinks. Do not agree to anything other than your $100 deductible. I am very curious about how Fidelity handles your claim, as I have the same Fidelity Platinum coverage that I purchased back in March. If they give you a problem then what is the point of coverage and I will consider cancelling my coverage with them.

Thanks,
Keith

glennhl

The head bolts are failing because of a bad design. There is a high stress area of the bolt where the internal wrenching feature is in the bolt's head. They went to an external wrenching feature and got rid of the thin area. Now with that said, I'm guessing it takes a little corrosion to push the bolt over the edge where it will break. I would be very interested in a weibull distribution of bolt failures so far. It's like tracking popcorn popping. For the longest time only a few pop, then they all start popping. I have to tell you, if I had a 2010 or earlier, I think I would be proactive and put in the new headbolts (one at a time).

Also, once a bolt is torqued down, you can not increase the load on it unless you stretch it further (think of a bolt as a spring in tension). The combustion chamber pressure is not enough to push the head off it's gasket, at least for a normally aspirated engine, therefore the bolt stresses do not go up with the engine running. The only thing that really increases the bolt loads is if the head thermally expands more than the bolts. And again, I'm sure Mercedes accounted for that. So running your NA Engine hard does not increase your bolt stresses any more than running it normally.

As far as the OP, I would not be at all surprised if it turns out to be a head bolt failure and if it is, I am also willing to bet that your warranty will cover the work. Good luck.

CSIKTY3

I agreed to the tear down yesterday dealer called me today and they have confirmed the headbolts are broken, They told me the head gasket leaking is covered over the phone but I didnt get into specific asking about headbolt. They will inspect the car Tuesday I will update as I get more info.

Funny enough I too heard aftermarket warranties cut AMG and M cars but it I honestly heard only good things about Fedelity so im crossing my fingers

AMG6.3

I see that you have a tune, did you flash back to stock prior to going to MB dealership?

-Marlin-

I would start with Mercedes Benz. This is a known problem no matter how dumb they pretend to be about it. What is known is that there was a head bolt redesign in 2011. Why was that? Hmmmm....speak right up?

I'd start with Mercedes. They need to own this if it was headbolt failure. Heck with the warranty company at this point in time.

CSIKTY3

yea they all act like its not a common problem

CSIKTY3

No, the dealer does not delete the tune (as far as I know)

CSIKTY3

Unfortunatly everyone I know with this has tried and has failed. Mercedes does not want to own up to it..

Ingenieur

Except they are paying for it
The affected cars are out of warranty
People like to gripe
Remember the e46 M3 rod bearing issue? It was all over the web
We have a thread on this forum
We have tens of 1000's of members
A large % in the c63 forum
Only a few posts with any proof: pics, in oice, etc
This with cars approaching 8 years old and higher mileage
Everybody says their dealer is fixing dozens lol
My 4 local dealers say they have done none

Ingenieur

Only MB knows the stats
If they saw it was likely or a high percentage they would be proactive
Especially in the land of class action litigation
They like their odds, they know there won't be many and they can manage it with good will contributions

glennhl

Or, just maybe, they have already run the Weibull plot and know that most of the failures will happen outside of warranty, therefore they do not need to do a recall. These failures are going to get worse, not better, and I'm betting we are in the first part of the Weibull plot and the popcorn is really going to start popping a few years from now. Remember, someone in this thread said it was most likely not a head bolt issue. I stuck my neck out and said it was.