What would cause an oil leak on the valve cover?
06-16-2014, 08:29 AM
#1
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What would cause an oil leak on the valve cover?
I have had this issue for almost 2 months now and have had numerous parts changed over at the dealer. I am wondering what would cause a leak like this if the parts listed below have already been repaired and changed over.
The following parts have been changed
This was a note from the dealer on my most recent invoice;
"CHECKED FOR OIL LEAKING DUE TO EXCESSIVE SMOKE COMING FROM
ENGINE COMPARTMENT. COMPLETED RE AND RE DRIVERS SIDE VALVE COVER AND REPLACE GASKET AND O RINGS FOR THE FOUR CYLINDERS."
And here are some pictures;
The car doesn't seem to be going through significant oil since I haven't had any warnings to add oil. In addition the leak seems to be worse when the car is driven with the traction off and in S+. However, the leak is still present in comfort settings. The leak doesn't seem to affect any driving dynamics or performance there is only visible white smoke coming out from the back of the engine bay and a strong burning smell. The dealer is trying hard to fix the issue and Im sure they will get to it but I am just posting to see what you guys might think.
Thanks!
The following parts have been changed
- Oil Filler Cap
- Valve Cover Gasket
- Valve Covers - Left Side
This was a note from the dealer on my most recent invoice;
"CHECKED FOR OIL LEAKING DUE TO EXCESSIVE SMOKE COMING FROM
ENGINE COMPARTMENT. COMPLETED RE AND RE DRIVERS SIDE VALVE COVER AND REPLACE GASKET AND O RINGS FOR THE FOUR CYLINDERS."
And here are some pictures;
The car doesn't seem to be going through significant oil since I haven't had any warnings to add oil. In addition the leak seems to be worse when the car is driven with the traction off and in S+. However, the leak is still present in comfort settings. The leak doesn't seem to affect any driving dynamics or performance there is only visible white smoke coming out from the back of the engine bay and a strong burning smell. The dealer is trying hard to fix the issue and Im sure they will get to it but I am just posting to see what you guys might think.
Thanks!
06-16-2014, 10:58 AM
#3
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2012 C63;1971 280SE 3.5(Sold);2023 EQS 450 SUV 4 Matic (Wife's)
From the pic it appears you have a leak from the filler cap and the o-rings that seal the cover to the head in the plug wells. Are these pics from before or after the repairs? Oil is dripping on the exhaust manifold and that is why you have smoke and a strong odor of burnt oil. It is stronger when driven hard because the cam shafts are turning faster and throwing more oil around at a greater velocity and the exhaust manifolds and engine parts in general are hotter.
If the repairs did not fix the leak then perhaps the valve cover itself has warped.
If the repairs did not fix the leak then perhaps the valve cover itself has warped.
06-17-2014, 10:49 AM
#4
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Thanks guys. The pictures are from before the most recent repair. I took the car into the dealer again this morning for them to review. The oil seems to be coming out the very back of the valve cover closest to the windshield. They replaced the valve cover so it should be something else. This all started after I had my oil changed at Victoria Star Motors in Kitchener so maybe something to do with that?
06-17-2014, 12:00 PM
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2012 C63;1971 280SE 3.5(Sold);2023 EQS 450 SUV 4 Matic (Wife's)
I don't think an oil change could cause these leaks. The worst might be the oil cap gasket wearing out but even that is doubtful.
The fact it is leaking from the back of the valve cover after the repairs leads to a botched repair. It looks like the gasket was not properly in place when the valve cover was bolted back down into place. It would be pretty easy to dislocate the gasket when setting the cover on the head if the tech was a little careless. Either that or the valve cover was not properly torqued down or not in the correct sequence.
Wait to see what the dealer has to say.
The fact it is leaking from the back of the valve cover after the repairs leads to a botched repair. It looks like the gasket was not properly in place when the valve cover was bolted back down into place. It would be pretty easy to dislocate the gasket when setting the cover on the head if the tech was a little careless. Either that or the valve cover was not properly torqued down or not in the correct sequence.
Wait to see what the dealer has to say.
06-17-2014, 04:26 PM
#6
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I don't think an oil change could cause these leaks. The worst might be the oil cap gasket wearing out but even that is doubtful.
The fact it is leaking from the back of the valve cover after the repairs leads to a botched repair. It looks like the gasket was not properly in place when the valve cover was bolted back down into place. It would be pretty easy to dislocate the gasket when setting the cover on the head if the tech was a little careless. Either that or the valve cover was not properly torqued down or not in the correct sequence.
Wait to see what the dealer has to say.
The fact it is leaking from the back of the valve cover after the repairs leads to a botched repair. It looks like the gasket was not properly in place when the valve cover was bolted back down into place. It would be pretty easy to dislocate the gasket when setting the cover on the head if the tech was a little careless. Either that or the valve cover was not properly torqued down or not in the correct sequence.
Wait to see what the dealer has to say.
The most recent update from the dealer;
- Replace Intake Gaskets
- Left Rocker Cover Gsket is Cracked (Possibly too much pressure)
- Inspect PCV Valve
It seems as though the dealer may have figured this one out. Ill keep you guys posted.
02-28-2017, 11:57 AM
#7
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I know its been a while but what was the outcome?
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10-29-2018, 02:55 PM
#10
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I also had an oil leak issue, that we thought was coming from the valve covers, and in actuality came from cam adjuster cover.
But in your case, purchase a new oil filler cap, then have the valve cover gaskets changed.
But in your case, purchase a new oil filler cap, then have the valve cover gaskets changed.
11-29-2018, 12:56 PM
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C63 Coupes (2013)
Valve cover oil leak
Just had a similar problem, got the solution from here so thanks for that.
Had oil leak from around the back n/s valve cover bolt on my 2013 C63 Coupe, smoke, burning etc. Obvious cheap fix was the gasket as it was not running from elsewhere to no avail. Garage had no further input. FYI There’s no rubber grommets on the bolts, just a metal bolt and metal sleeve. As garages are useless and actual mechanics no longer exist I then got the valve cover itself replaced as the oil was sitting on top of the valve cover around the bolt - after some investigation this seemed the logical next step. (No PCV noises etc) Magically after asking them to show the old cover to me, behold a 2” crack somehow not seen when replacing the gasket!... wishing I’d done it myself after 3 visits to the garage - I didn’t as couldn’t be bothered with all the wires and hoses assuming it would be a quick fix.
In short the valve cover is made out of cr@p plastic and not metal - I assumed it was metal with a plastic cover, it’s not, just a £200 piece of plastic so if you have similar problems (I’ve seen lots of talk of sealant etc - don’t!).... if the oil is on the top, around the bolts and not running from elsewhere, it’s likely due to a cracked valve cover.
Had oil leak from around the back n/s valve cover bolt on my 2013 C63 Coupe, smoke, burning etc. Obvious cheap fix was the gasket as it was not running from elsewhere to no avail. Garage had no further input. FYI There’s no rubber grommets on the bolts, just a metal bolt and metal sleeve. As garages are useless and actual mechanics no longer exist I then got the valve cover itself replaced as the oil was sitting on top of the valve cover around the bolt - after some investigation this seemed the logical next step. (No PCV noises etc) Magically after asking them to show the old cover to me, behold a 2” crack somehow not seen when replacing the gasket!... wishing I’d done it myself after 3 visits to the garage - I didn’t as couldn’t be bothered with all the wires and hoses assuming it would be a quick fix.
In short the valve cover is made out of cr@p plastic and not metal - I assumed it was metal with a plastic cover, it’s not, just a £200 piece of plastic so if you have similar problems (I’ve seen lots of talk of sealant etc - don’t!).... if the oil is on the top, around the bolts and not running from elsewhere, it’s likely due to a cracked valve cover.
