DutchC63

Upon checking coolant level showed level had dropped significantly. Warning light did not come on yet but I am concerned with all the stories about the head bolt issue. Mine certainly was build within the affected model range and I would want to have the updated head bolts and new valve seats installed under warranty. Only 24k on my 2009 , used only as weekend car. The car runs ok otherwise but when the engine is cold running idle it sounds as if one of the cylinders skips a beat ones in a while.
Stay tuned.
E

olszowa12

I've had the "check coolant level" message pop up at least 15 times in the last 4 years.
My car is 2008 built. No issues until now.
I noticed that when it's cold in the morning, the message is more likely to appear on the dashboard.

motoman

Since progress is slow on looking at the bolts for defects maybe some information on driving styles would help us understand whether hard or average throttle application has any effect upon this problem.

"My" C63 is driven daily by wife, 25K miles, no problems. I have an oil analysis kit I have not sent in.

So what are your driving styles and weekly mileages?

roadtalontsi

2010 with weistec blower. stock head bolts 26k mi. beaten on daily, 200miles a week. occasionally drag stripped.

tfthach13

I'm no expert on the subject, but I don't believe driving style has to do with the coolant/head bolt issue. I am however, interested in what ENGINE OIL (Mobil1, etc.) people use that have this coolant/head bolt issue.

I have a theory that the "recommended" viscosity (0w40, now 5w40) has something to do with the coolant/head bolt issue.

motoman

Keep it coming, guys.

Lift-off (head) pressures increase dramatically at open throttle and high rpms. If normally aspirated , much less forced induction engines survive which are in the affected SN range, it is significant. That may signal mixed lots of bad/good headbolts which MB did not control.

Merc63

You probably have the revised bolts being a 2010 or did you get screwed like me?


I wouldn't trust those old bolts with the blower, no way.

DutchC63

4K mls/yr, probably 70-80% city stop and go , rest freeway mls 60-80mls/hr with an occasional burst to 100-110 when I feel like it subject to traffic conditions of course. I ALWAYS warm up the engine before putting my right foot down. Bought the car when it was 6 months old with 9Kmls on it. In the beginning I had to add a quart of oil between service intervals but that was only the first year. I have never had to add any oil since. The radiator was flushed a year ago and full 10 months ago with no more than 3 Kmls driving. Car always gets serviced by the dealership with the recommended Mobile 1, not sure of the viscosity though. Considering its potential the engine is used far below its enormous HP potential and should therefore not see the coolant drop this much. In fact I have had many cars, Audi's, BMW' etc which were pushed a lot harder with more mls/yr and never had to top off with coolant!

motoman

Useful info and I agree that coolant is normally stable. Stay with us on the serial number of your car and the dealer response. The oil kit I mentioned looks for coolant or you can get ? litmus style that looks for oil in coolant. Keep us posted .

Bigspider

5w40??? On the mobil 1 site, the recommended oil for my 2010 c63 is 0w40.

CoolBDPhenom03

MB now recommends 5W40. Either is fine though.