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M156 head deformation revealed during preventive head bolt replacement
Hello, everybody.
Firstly thanks for a lot of good information and helpful people on this forum.
With 85000km on odometer I have decided to address head bolt problem on my 2007 cls (with no coolant leak experience so far) and during the head removal in the authorized service center they announced me one of the heads "was deformed" or "wry" and they "put it in proper shape".
None of the bolts was broken and they only told me they were loose and could be un-screwed by bare hand.
I could not find any single case of anybody experiencing such "head deformation" via searching over Internet.
What are your opinions about this ? Are they playing small tricks on me ?
Mo. I don't believe they are. Heads warp because of uneven pressure on them. Your bolts were not uniform in terms of torque so it is entirely possible and most probable that they are not messin with you.
Multiple head bolts "Unscrewable by hand" sounds like a big exaggeration at best. The bolts would continue to unscrew themselves at that point and copious amounts of coolant would be leaking out.
For a car without a leak that is not likely.
Also for a car without a leak a warped head is not likely.
Also "put it in proper shape" sounds like just BS from someone who does not know what he is talking about.
If you spoke to the guy working on your car I would be very concerned, if it was a service advisor as always ignore that guy and speak to the guy working on your car.
Also did they charge you for the "proper shape" work?
Hello all, thanks for your replies, haven't been here for a while so got your replies right now.
Here on the picture there are colour differences between new sample of Mobil1 0w40 oil and supposedly same oil after roughly 400km (250 miles) of driving after last oil change.
Do you think the "new after 250 miles" oil colour is appropriate ?
The difference was more contrast initially and blurred a bit after few minutes.
Multiple head bolts "Unscrewable by hand" sounds like a big exaggeration at best. The bolts would continue to unscrew themselves at that point and copious amounts of coolant would be leaking out.
For a car without a leak that is not likely.
Also for a car without a leak a warped head is not likely.
Also "put it in proper shape" sounds like just BS from someone who does not know what he is talking about.
If you spoke to the guy working on your car I would be very concerned, if it was a service advisor as always ignore that guy and speak to the guy working on your car.
Also did they charge you for the "proper shape" work?
Yes, they did charge me 190 Eur ($210) for the "external company head repair".
03-17-2016, 04:29 AM
