C-Class (W204) 2008 - 2014: C180K, C200K, C230, C280, C300, C350, C200CDI, C220CDI, C320CDI
Old 06-15-2015, 04:11 PM
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Old 01-13-2015, 07:59 AM
  #26  
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2013 C300 4matic Sport
I have resealed quite a few of the vacuum pumps, never replaced one for failure. They are not difficult by any stretch, but not as simple as the cam plugs. There is a slot that fits in the camshaft and allows it to drive the pump. Just remove the vacuum line, bolts and pull away from engine (toward back of engine). Then clean and reinstall! Alldata says 1.3hrs total.
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Old 01-19-2015, 06:26 PM
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'08 C300 MM Pano
Originally Posted by xjmoe83
I have resealed quite a few of the vacuum pumps, never replaced one for failure. They are not difficult by any stretch, but not as simple as the cam plugs. There is a slot that fits in the camshaft and allows it to drive the pump. Just remove the vacuum line, bolts and pull away from engine (toward back of engine). Then clean and reinstall! Alldata says 1.3hrs total.
Thank you so much for your post.

Let me first confirm that the dealer I went to (Downtown L.A. MB) cinfrimed that the O-ring is indeed available as a separate part. To replace the pump, it would have been $288 (part only)... Whereas the O-ring was a mere $5.15.

And I agree that this was a pretty simple DIY. My biggest difficulty was finding a Torx bit that will fit between the bolts and the fire wall. As a heads up, Torx bit that are part of a socket (pictured below) will not work. Becasue by the time you pop that socket onto a ratchet, it becomes too long to fit.



Thee won't work either:



The only ones I could fit were similar to this one:



Which would then create the need for some sort of 1/4" wrench to do the loosening and tightening... I happened to have a 1/4" combination ratcheting wrench which made for an easy task.

Although I have not driven the car much to account for "testing" for leaks since then, I will keep an eye on it to see if -in my case- replacing the O-ring has sufficed. I will update here again soon.

Thanks again for your encouragement, xjmoe83.
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Old 01-22-2015, 05:23 PM
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No prob! I have a 1/4" hex drive similar to the picture that accepts the exact same t30 bit you posted. I also cut my t30 bit pretty much in half to make a bit more space. Good luck !!
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Old 04-19-2015, 07:50 AM
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2009 c300 sport
Originally Posted by Glyn M Ruck
Check your cambox covers for leaks & especially the cam bore blankers & covers on the back of the heads. These sometimes leak onto the manifolds/exhausts on the M272. Those two round rubber plugs being the most common. Easy fix.

i have an oil leak coming from the cover left side of picture the big one. i removed and looks like a orange gasket but i ouldn't find any part number for the gasket, do you know the pn? or the name for that to look thanks
Old 04-19-2015, 08:41 AM
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Originally Posted by candresarias
i have an oil leak coming from the cover left side of picture the big one. i removed and looks like a orange gasket but i ouldn't find any part number for the gasket, do you know the pn? or the name for that to look thanks
You need the vacuum pump gasket. The vacuum pumps are slightly different from model to model. The dealer can run your VIN for the exact gasket.
Old 04-19-2015, 09:43 AM
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2009 c300 sport

Originally Posted by xjmoe83
You need the vacuum pump gasket. The vacuum pumps are slightly different from model to model. The dealer can run your VIN for the exact gasket.
i am talking about the one on the red circle. i think the vacuum pump is the other one, right?
Old 04-19-2015, 09:51 AM
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2009 c300 sport
ok. yes it is the vacuum pump. you're right. i think i need the O ring if im right. part # 15 or the Vacuum assy
Old 04-19-2015, 11:05 AM
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'08 C300 MM Pano
Originally Posted by candresarias
ok. yes it is the vacuum pump. you're right. i think i need the O ring if im right. part # 15 or the Vacuum assy
As advised earlier, only the dealer can confirm part numbers by way of running your VIN.... But here are the numbers for the Vacuum Pump and the O-Ring for my 2008 C300 (which has a Vacuum pump).

Vacuum Pump: part # 272 230 04 65

O-Ring for Vacuum Pump: part # 021 997 36 45

Note that if you do not have a vacuum pump... Neither of the above number may apply!

Also... Some dealers may tell you that the O-ring (approximately $5) is not available without the vacuum pump (approximately $220)... My dealer took the o-ring off of a new pump and said "don't worry about it" (which I assume meant he will order a replacement o-ring...). So they must be available on their own.
Old 04-19-2015, 11:10 AM
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'08 C300 MM Pano
Originally Posted by candresarias



i am talking about the one on the red circle. i think the vacuum pump is the other one, right?
The red circle IS the vacuum pump (or if it just a cover, its the vacuum pump delete)... the large one the right side, is the oil separator/breather the part number for that is:

Breather: part# 272 010 06 31
Old 05-30-2015, 05:54 AM
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I have a 2009 with the same problem (oil leaking from red-circled area). I purchased the "vacuum pump o-ring" today but think the leak is really from the cover plate (one with the 5 screws) and not the seal from the pump to the block. Dealer pulled up the same drawing said no other o-ring was available and quoted $320 for a new pump.

I'm going to look a little closer to check leak starting point. With the design of the pump, I am skeptical how an oil leak from the o-ring (#15) would only show up at the edge of the pump cover plate. But after holding a new pump in my hand, I don't see how much oil goes into the pump either.



W204 Vacuum Pump
Old 05-31-2015, 01:20 AM
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'08 C300 MM Pano
Originally Posted by bweech
I have a 2009 with the same problem (oil leaking from red-circled area). I purchased the "vacuum pump o-ring" today but think the leak is really from the cover plate (one with the 5 screws) and not the seal from the pump to the block. Dealer pulled up the same drawing said no other o-ring was available and quoted $320 for a new pump.

I'm going to look a little closer to check leak starting point. With the design of the pump, I am skeptical how an oil leak from the o-ring (#15) would only show up at the edge of the pump cover plate. But after holding a new pump in my hand, I don't see how much oil goes into the pump either.
This is my unofficial explanation of how this works so don't quote me on it... The oil does not actually go through the pump. Instead it simply lubricates the spinning parts ("driver"/"drive plate")which, by design, create the vacuum.... and so on. As such, I think if you were to inspect this leak a little more carefully, you might find that it is indeed coming from the area where the pump assembly adheres to the block and not -as you are suspecting- from what appears to be the back cover.

In my opinion, the only way to make sure is to use some sort of cleaner to completely remove any and all oil residue from the entire circumference of the pump, give it a day or two and inspect it often to confirm where it is leaking from.

At any rate, and though I am not sure which area you are from, paying $320 for the pump itself -if it needs to be replaced- will be like throwing money away when the sources I have checked, charge around $220.

And lastly, I would double verify the part number shown on the image you posted which shows it as 2722300565 which I believe is the part for 2010 and up, and if you have a 2009, then the correct part should be 2722300465. (But I have been wrong before).

Good luck, and please, let us know how it works out!
Old 12-09-2015, 06:46 PM
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Mine finally gave up the ghost yesterday when I smelled a little burning oil, then saw a puff of smoke waft from under the hood...started thinking the worst but jumped on here and then under the hood and as usual, you guys saved the day!!
Picked up three new plugs (2 small, 1 large) for $15.44 with tax from the dealer and replaced them today.
Both plugs on the driver side looked to not be completely seated, or pulled out just a touch and it seemed they both were leaking...the smaller plug being the worst offender. The passenger side was fully inserted and wasn't leaking...hope I didn't screw up a good thing by replacing it!!
Anyhow, be sure to get them seated all the way in. That was the only tough part as it is very easy to snap them in but hard to get them seated fully.
And of course be careful to catch the old plugs when you pop them out if not, you will be leaving it on the belly pan or taking 20 mins pulling the pan and removing your oily plug....
BTW- The dealer quoted "about 300" before I started laughing about only popping in plastic plugs....then it came down to "about 200" and then even lower as I asked to be transferred to parts...

Last edited by C300Sport; 12-09-2015 at 06:53 PM.
Old 12-12-2015, 02:05 PM
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Good advice on ensuring proper seating.
Old 12-14-2015, 01:42 PM
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Thumbs up A HUGE THANK YOU to all!

I was experiencing the same burning plastic as many others in this forum. After searching here for answers, I ordered the cam head expansion plugs. After more research and reading all your posts, I decided to tackle the installation myself. I am not in any way a mechanic. I'm more of a start the car and turn up the radio kind of guy. Most of you said it's a 10 minute job, I planned on at least 30. Long story short, $13.00 including a hand mirror (recommended) and just under 15 minutes. Once again, thank you everyone. And now, since it's a very unusual 70 degrees in Upstate New York, it's time to drop the top and take the dog for a cruise!
Old 03-19-2016, 02:44 PM
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Originally Posted by bweech
I have a 2009 with the same problem (oil leaking from red-circled area). I purchased the "vacuum pump o-ring" today but think the leak is really from the cover plate (one with the 5 screws) and not the seal from the pump to the block. Dealer pulled up the same drawing said no other o-ring was available and quoted $320 for a new pump.

I'm going to look a little closer to check leak starting point. With the design of the pump, I am skeptical how an oil leak from the o-ring (#15) would only show up at the edge of the pump cover plate. But after holding a new pump in my hand, I don't see how much oil goes into the pump either.



W204 Vacuum Pump
The leak you have is from a seal that isn't sold separately. I had the same problem on a similar pump on my 2005 C230. What I did is remove the pump, remove the six torx screws and replace the seal with one I found at pep boys from an old filter that was the same size and thickness.

For the pump on that car I used this seal https://www.pepboys.com/product/details/9628926/00157, it really won't make a difference as long as it has the minimum thickness of the original one. Hasn't leaked since and has about 20k miles on it. Total cost was below $10 and a couple of cold ones. Definitely a DIY for anyone who doesn't want to drop the cash for a new pump just for a new seal.

Because they might not be the same pump, you could remove the pump remove the seal and go to your local parts store and check the oil filter section for an oil seal that is similar to the one that came out of the pump. Just make sure its is ever so slightly thicker since the old one will most likely be squared off.
Old 03-20-2016, 12:03 AM
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'08 C300 MM Pano
Originally Posted by jpman
The leak you have is from a seal that isn't sold separately.
I had one dealer tell me the same thing... My previous post:

Originally Posted by IGB
As advised earlier, only the dealer can confirm part numbers by way of running your VIN.... But here are the numbers for the Vacuum Pump and the O-Ring for my 2008 C300 (which has a Vacuum pump).

Vacuum Pump: part # 272 230 04 65

O-Ring for Vacuum Pump: part # 021 997 36 45

Note that if you do not have a vacuum pump... Neither of the above number may apply!

Also... Some dealers may tell you that the O-ring (approximately $5) is not available without the vacuum pump (approximately $220)... My dealer took the o-ring off of a new pump and said "don't worry about it" (which I assume meant he will order a replacement o-ring...). So they must be available on their own.
Edited to add: Actually here, a quick search revealed three different part number for the O-ring...

0219973645
0129978745
0169975045
All the above numbers should work with a 272 230 05 65....

Let me reiterate that only the selling shop can verify the correct number using your VIN.... Good luck!

Last edited by IGB; 03-20-2016 at 12:06 AM.
Old 03-20-2016, 12:17 AM
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2009 E63
Originally Posted by IGB
I had one dealer tell me the same thing... My previous post:



Edited to add: Actually here, a quick search revealed three different part number for the O-ring...

0219973645
0129978745
0169975045
All the above numbers should work with a 272 230 05 65....

Let me reiterate that only the selling shop can verify the correct number using your VIN.... Good luck!
The o-ring you're mentioning is not the same one I was referring to. The o-ring you speak of goes between the engine and the pump. That one is readily available. The o-ring that I speak of is part of the actual pump and goes towards the back side of the pump in between a cover that is held by 6 screws and the pump itself.
Old 03-20-2016, 10:31 AM
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Originally Posted by jpman
The leak you have is from a seal that isn't sold separately. I had the same problem on a similar pump on my 2005 C230. What I did is remove the pump, remove the six torx screws and replace the seal with one I found at pep boys from an old filter that was the same size and thickness.

For the pump on that car I used this seal https://www.pepboys.com/product/details/9628926/00157, it really won't make a difference as long as it has the minimum thickness of the original one. Hasn't leaked since and has about 20k miles on it. Total cost was below $10 and a couple of cold ones. Definitely a DIY for anyone who doesn't want to drop the cash for a new pump just for a new seal.

Because they might not be the same pump, you could remove the pump remove the seal and go to your local parts store and check the oil filter section for an oil seal that is similar to the one that came out of the pump. Just make sure its is ever so slightly thicker since the old one will most likely be squared off.
Out of curiosity, when this was leaking, did it cause a vacuum leak in addition to the burning smell?
Old 08-22-2016, 04:38 PM
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I have the breather cap on the right side leaking. Yesterday it started smoking We've had high winds lately. Maybe it only seems worse than it is..

Q. Does it require removal of the MAF sensor? That space looks tight. Mine is a 2009 C350.



Originally Posted by Glyn M Ruck
Check your cambox covers for leaks & especially the cam bore blankers & covers on the back of the heads. These sometimes leak onto the manifolds/exhausts on the M272. Those two round rubber plugs being the most common. Easy fix.

Old 08-22-2016, 05:54 PM
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'08 C300 MM Pano
Originally Posted by Funkwagen
Out of curiosity, when this was leaking, did it cause a vacuum leak in addition to the burning smell?
Not in my case....
Old 08-22-2016, 05:57 PM
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'08 C300 MM Pano
Originally Posted by Nicholi2007
Q. Does it require removal of the MAF sensor? That space looks tight. Mine is a 2009 C350.
Not at all. Removing the air filter housing/engine cover, yes... But not the MAF sensor.
Old 08-23-2016, 09:44 AM
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'08 C300 MM Pano
Originally Posted by Funkwagen
Out of curiosity, when this was leaking, did it cause a vacuum leak in addition to the burning smell?
Originally Posted by IGB
Not in my case....
Let me 1st reiterate my previous response... But I would also like to add the following, which by doing so, I'm going out on a limb, as it is only speculation at this point. I have not removed the parts (o2 sensors) in question and I can not confirm or deny if this issue is related to bad O2 sensors, but when it comes to possible side effects of this oil leaking, if you were to look straight downwards from over the vacuum pump/vacuum pump delete (larger yellow circle on the left side of the image above), you will see that any oil droplets will land right where one of the two O2 sensors is located on that branch of the exhaust (I think it is the pre-cat O2 sensor). I can only imagine that the threaded part of an O2 sensor is a pretty tight fit and it won't allow for any oil to seep through to the inside, however, if it does get on the wiring, I can only assume that it might permeate through there and, in spite of the high temperature these O2 sensors might reach, the oil might cause some fouling and eventually, an O2 sensor that is not doing its job.

I will be replacing all 4 O2 sensors in the next few days and will update this comment accordingly "if" (and only if) I see anything unusual.
Old 08-31-2016, 01:16 AM
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2009 C350
Having a hell of a time getting the breather cover off. The screws are on so tight. All I have is an allen. I think I'll strip them. counter clockwise?



Originally Posted by IGB
Thank you so much for your post.

Let me first confirm that the dealer I went to (Downtown L.A. MB) cinfrimed that the O-ring is indeed available as a separate part. To replace the pump, it would have been $288 (part only)... Whereas the O-ring was a mere $5.15.

And I agree that this was a pretty simple DIY. My biggest difficulty was finding a Torx bit that will fit between the bolts and the fire wall. As a heads up, Torx bit that are part of a socket (pictured below) will not work. Becasue by the time you pop that socket onto a ratchet, it becomes too long to fit.



Thee won't work either:



The only ones I could fit were similar to this one:



Which would then create the need for some sort of 1/4" wrench to do the loosening and tightening... I happened to have a 1/4" combination ratcheting wrench which made for an easy task.

Although I have not driven the car much to account for "testing" for leaks since then, I will keep an eye on it to see if -in my case- replacing the O-ring has sufficed. I will update here again soon.

Thanks again for your encouragement, xjmoe83.
Old 08-31-2016, 03:15 AM
  #49  
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'08 C300 MM Pano
Originally Posted by Nicholi2007
Having a hell of a time getting the breather cover off. The screws are on so tight. All I have is an allen. I think I'll strip them. counter clockwise?
Where in LA are you located?

Let me check and see if I can find the socket/ratchet I used, I can meet you somewhere tomorrow or the day after if you wanna borrow them. (I'll update this post in a short while if I still have them)

Last edited by IGB; 08-31-2016 at 03:17 AM.
Old 08-31-2016, 03:19 AM
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I'm down the street from the Grove Shopping Center. Did you turn them counter clock wise? I'm starting to think they were torqued....


Originally Posted by IGB
Where in LA are you located?

Let me check and see if I can find the socket/ratchet I used, I can meet you somewhere if you wanna borrow them. (I'll update this post in a short while if I still have them)


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