What's the realistic probability of head bolt failure?
#1
MBWorld Fanatic!
Thread Starter
What's the realistic probability of head bolt failure?
Has anyone really come across a head bolt failure on these 63's? I'm not sure if the 507 hp engine was different than the regular C63's that had issues?
#2
Super Member
Join Date: Dec 2009
Location: Dhahran, KSA
Posts: 743
Received 91 Likes
on
73 Posts
2020 E 300 Coupe and 2019 GLS 400
The C63 507 Has the updated head bolts, and all M156 engines produced post mid-2011. The engine serial number is the way to verify.
I have only seen a handful of incidents, all of them were reported by Mercedes forums members. This issue affects engines up to serial # 60658. Let us say that only 5% of these engines would suffer the failure during operational lifetime, this translates into 3033 engine hydro locking or blowing-up (worst case scenario). If that was the case, MB/AMG would've done something about it (Like the W211 fuel tank recall, or the M272 timing warranty extension).
All in all, the chances of it occurring are slim, but if it happens, then the owner is out of luck.
I have only seen a handful of incidents, all of them were reported by Mercedes forums members. This issue affects engines up to serial # 60658. Let us say that only 5% of these engines would suffer the failure during operational lifetime, this translates into 3033 engine hydro locking or blowing-up (worst case scenario). If that was the case, MB/AMG would've done something about it (Like the W211 fuel tank recall, or the M272 timing warranty extension).
All in all, the chances of it occurring are slim, but if it happens, then the owner is out of luck.