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2016 c450 amg m276.3 oil leak (help identifying these parts please)
so yesterday I was performing my oil change on my 2016 c450 amg
this car just got out of warranty so it was the first time for me doing the oil change
right away i notice a leak coming down from the top
after inspection, it seems to be leaking from the driver side cylinder head
very disappointed since this car has always been maintained by mercedes benz themselves and they never mentioned there was an obvious major leak coming down the top of the engine
it looks like they never saw that (for me it was obvious)
i have been googling around trying to identify the part exactly without success
any tips would be greatly appreciated as to common leaking problem with this engine m276.3 or car w205 2016 c450 amg
or simply help to identify the parts / valve itself so that i can do further research
the part im looking seems to be attached to the front end of the cylinder head and im not sure what is leaking exactly
the oil seems to be going out near the rod or a bolt....
see attached pictures:
That leak is from the front cylinder head covers. Pretty straight forward job. Remove the covers, clean and reseal. Technically, they are not supposed to leak but they do.
Yes, common leak. Need to diagnose for certain if the leak is from the cylinder head cover or the cam magnets. Cam magnet reseal is fairly easy. Cylinder head covers require careful and thorough cleaning without damaging the machined surface. Then using the right type and quantity of sealant. Then using new aluminum screws torque to the proper (low) torque.
Use the search feature or google with site:mbworld.org, this is addressed in this site.
How many hours do you think it would take a competent mechanic to perform the work. Like reseal the head cylinder cover and two cam magnets? I live in Montreal its either 195$ cad per hour or 125$ if I go to an unofficial MB mechanic.
Frankly the fact this has been leaking for a while makes me very uncomfortable to go see a MB dealership.
I cant figure out how they missed such an obvious leak.
I called MB tech advisor they say the reseal is listed as 1h they can even guarantee it esp on the cylinder on the driver side easier to access than left side it seems. Good news. Not sure if there is any other leak. Might as well pay up 200$ for a full inspection to get an advice about the engine itself.
I would definitely inspect this area regularly. I had this done at the dealership (they bill you for every single thing they use on the job and the MB cleaning agent is $40 so it adds up quick!) and when I got the car home I discovered they had not even torqued the bolts down! The were still finger loose.
I made them redo the whole job, and 6 mos later it's leaking again. So another 2 days at my overbooked/understaffed dealership.
I would definitely inspect this area regularly. I had this done at the dealership (they bill you for every single thing they use on the job and the MB cleaning agent is $40 so it adds up quick!) and when I got the car home I discovered they had not even torqued the bolts down! The were still finger loose.
I made them redo the whole job, and 6 mos later it's leaking again. So another 2 days at my overbooked/understaffed dealership.
Or I could just do it myself.
that's why im gonna do the job myself you are never better served than by yourself. you are never more careful about the thing you own than yourself either. forum was very helpful. way more than MB. imo this c450 was serviced at benz for 5 ****ing years and no heads up on a front cover oil leak. its blatant that oil was leaking for a while. i also have the rattle problem at start documented in xentry where you have to install check valve. if anybody could recommend a sealant or is it a gasket? and something to clean the ****ing mess. **** has been leaking for months if not years.
*UPDATE* started the engine today. and the engine is smoking white and the rattling sound is stronger. when i switch from park to drive its even worst whole car shaking. oil level is normal. last weekend i made oil change everything went well (thats when i noticed the leak). yesterday i changed the air filters and the dust filter. nothing special went super smooth. engine is clacking. attached is a yt video. i feel like i got a ****ing lemon and i regret switching from porsche to MB.
Yes, common leak. Need to diagnose for certain if the leak is from the cylinder head cover or the cam magnets. Cam magnet reseal is fairly easy. Cylinder head covers require careful and thorough cleaning without damaging the machined surface. Then using the right type and quantity of sealant. Then using new aluminum screws torque to the proper (low) torque.
Use the search feature or google with site:mbworld.org, this is addressed in this site.
Yes, thats exactely whats occuring with mine. A reseal with Mercedes RTV and replace the 16 stretch bolts and youre good !
UPDATE. Its worst than we first thought. After removing air intakes and air filters and cleaning all the oil leaks, its blatant that the right head gasket is leaking, right cam magnets are both leaking, the front head cylinder cover on the right is leaking and the oil is smelling gas. Which makes sense because the care is smoking white. I went to benz to confirm my diagnostic. After spending 2 hours and charging me 400$, they confirmed I was 100% right. In addition they say left side also started leaking. The gaskets, the sealant and the o ring behind the cam magnets are super stiff probably because the car did not run for a few months. So it seems I am completely screwed up. Dealership said for a tedious job like that, they dont estimate up front. They start the meter and thats it. Could easily go in the 5000-10000$ range. Any advice? I am thinking literally fitting in a new engine at this point. Am I stuck with the original one or could I fit a c43 amg with no mods?
I would definitely inspect this area regularly. I had this done at the dealership (they bill you for every single thing they use on the job and the MB cleaning agent is $40 so it adds up quick!) and when I got the car home I discovered they had not even torqued the bolts down! The were still finger loose.
I made them redo the whole job, and 6 mos later it's leaking again. So another 2 days at my overbooked/understaffed dealership.
Or I could just do it myself.
What mileage did this start happening? I assume near or just over 100K?
UPDATE. Its worst than we first thought. After removing air intakes and air filters and cleaning all the oil leaks, its blatant that the right head gasket is leaking, right cam magnets are both leaking, the front head cylinder cover on the right is leaking and the oil is smelling gas. Which makes sense because the care is smoking white. I went to benz to confirm my diagnostic. After spending 2 hours and charging me 400$, they confirmed I was 100% right. In addition they say left side also started leaking. The gaskets, the sealant and the o ring behind the cam magnets are super stiff probably because the car did not run for a few months. So it seems I am completely screwed up. Dealership said for a tedious job like that, they dont estimate up front. They start the meter and thats it. Could easily go in the 5000-10000$ range. Any advice? I am thinking literally fitting in a new engine at this point. Am I stuck with the original one or could I fit a c43 amg with no mods?
Any update? It's not clear what mileage this happened at. Hopefully it wasn't too painful.
I'm almost scared to buy a C450 at nearly 80 miles I've been looking.
My wife's care had both cam/timing covers fail/leak at around 80K miles. My driver's side has started at around 50K miles.
I just watched this video for a C400. Sometimes it can be just the magnets but he also links to Google drive for the workshop instructions in resealing.
10-23-2022, 10:53 AM
