W204 C63 head bolts

[Rich764089]

Hi. Just looking for clarification whether the C63 PP had upgraded head bolts over the standard car?
Many thanks.

 

[Jobsworth]

No. The difference is at an age point rather than a specific model. Somewhere I have the chassis number cut off between early and late, but honestly I haven’t seen any for so long now, I think all those that were going to fail already have or they’ve already been replaced

 

[Rich764089]

No. The difference is at an age point rather than a specific model. Somewhere I have the chassis number cut off between early and late, but honestly I haven’t seen any for so long now, I think all those that were going to fail already have or they’ve already been replaced

Thanks very much, that's what I thought. Someone is trying to persuade me PP had upgraded head bolts from the factory.
Thanks again.

 

[badgx]

There were 3 different types of bolts used for the M156 line up. I have no idea why they used different ones?

The first ones were of T55 head, I think up to years 2008/9, which are good but you do need to make sure you do regular changes in antifreeze as it contains inhibitors to prevent corrosion.
They then went over to the T60, they are the most dangerous bolts used, it had very little material on the head. Those were found from around 2009 up to 2011/12. They then went with the E14 bolts onwards which have a lot more material on the head, less chance of breaking off.

 

[badgx]

Just a side view. E14 verses T55.

 

[Rich764089]

There were 3 different types of bolts used for the M156 line up. I have no idea why they used different ones?

The first ones were of T55 head, I think up to years 2008/9, which are good but you do need to make sure you do regular changes in antifreeze as it contains inhibitors to prevent corrosion.
They then went over to the T60, they are the most dangerous bolts used, it had very little material on the head. Those were found from around 2009 up to 2011/12. They then went with the E14 bolts onwards which have a lot more material on the head, less chance of breaking off.

Great info thanks I never realised there were 3 types. I'm looking at a 2008... Hadn't realised they were potentially less of an issue than 2009-11 cars!

 

[badgx]

I've never heard of any head bolts issues in UK but across the pond in hot countries, maybe they use tap water or something? Those bolts had corrosion attacking the underside of the head bolts weakening it. The T60 were the worst ones they used

 

[350cls]

And those that aren't in a garage and haven't been looked at are more than likely on original headbolts. Big hype, scare mongers.

Other model AMG have as more hyped faults like the early m157 weak drive chain and the wiring harness oil contamination issue.

I would say on the m156 the cam adjusters will show signs of troubles way before the headbolts. Like has been said, two year coolant renewals with distilled water is one preventive avenue.

 

[350cls]

On my early 212 63. I had to change an oil cooler pipe that was situated just in front of the front wheel behind the wheel well casing. The water from the driven wheel was splashing up and into the wheel casing vent with in time weakend the metal/corroded the pipe. It was a right awkward job to do. I couldn't get a brand new pipe anyway for the job. I managed to source a pipe second hand in the end which has worked perfectly every since. There was no room at all to work. It was a small pin hole that appeared right on the bend of the particular pipe. If I remember righty I blocked off that vents that threw the water splash with good quality adhesive tape.

I'm just giving an example of something that you never expect to cause an issue but it does and could be a costly one. Over something that is hyped about that you could never experience or something that you could be unlucky to experience.

 

[BlackC55]

People also think that this is a common issue. It certainly isn't. Ive hardly seen any.