Oil and coolant leak from oil cooler on 2010 W212 M271

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Oct 26, 2019 | 07:40 AM
  #1  
Hi all,

It seems that I have an oil and coolant leak from oil cooler on 2010 E250 CGI W212 M271 1.8T VIN: WDD2120472A296740

The oil and coolant are dripping down the left hand side of the engine block behind the starter motor and a bit further up.
The starter motor is in the way of oil cooler, so I cannot see clearly. I can feel that the oil cooler is wet. I'm pretty sure that the
oil cooler gasket is damaged, so I'll have to attempt to replace it.
I know that I'll have to drain the engine oil and coolant from the engine before I remove the oil cooler in order to avoid total mess.
The only way to get remove the oil cooler is to remove the starter motor, as far as I can see.

Would anybody please know how to approach this oil cooler gasket replacement task? How to remove starter motor?


Thanks

Milo


Reply 0
Nov 30, 2019 | 04:48 AM
  #2  
Hi all,

The gasket was stuffed (part # A2711840280). Replaced the gasket, but it still leaks. I wasn't aware of 4 rubber seals inside the oil cooler, so I have ordered those seals now.
Would anybody know the torque values for the 5 bolts which hold the oil cooler attached to the engine block, please?

Thanks

Milo



Broken seal

New seal

Reply 0
Oct 16, 2020 | 06:38 AM
  #3  
Hi Milo,

I have this exact issue on my e250 cgi, and has been steadily dripping for 2 years! I've bought the gasket and am tempted to have a go at replacing it. Could you give any further details on the process you used in the end. I was going to approach from top down, but see you were thinking of going in from the underside? I'm also after the part number for the 4 additional seals you mentioned if possible? Any help much appreciated,

Ches

Reply 0
Oct 16, 2020 | 06:53 AM
  #4  
E250 oil filter housing leak
Oh and also, did the replacement of the 4 seals then go on to cure the leak?
Reply 0
Oct 16, 2020 | 10:15 AM
  #5  
Holy cow, the oil cooler base body is plastic too ?
Wow, I best check on my M276 DELA 30
I hate seeing plastic doing such hot and 5 BAR pressure work
Thanks for posting. Sorry about your leak though.
Reply 1
Oct 16, 2020 | 10:23 PM
  #6  
Quote: Hi Milo,

I have this exact issue on my e250 cgi, and has been steadily dripping for 2 years! I've bought the gasket and am tempted to have a go at replacing it. Could you give any further details on the process you used in the end. I was going to approach from top down, but see you were thinking of going in from the underside? I'm also after the part number for the 4 additional seals you mentioned if possible? Any help much appreciated,

Ches
Hi Ches,

Have a look at the PDF attachment. good luck!

Thanks

Milo


Reply 0
Oct 17, 2020 | 01:53 PM
  #7  
Hi Milo,

Thats great thanks. Couldnt have hoped for better details!

Cheers
Reply 0
Oct 17, 2020 | 07:27 PM
  #8  
Quote: Hi Milo,

Thats great thanks. Couldnt have hoped for better details!

Cheers
You're welcome, Ches!

Milo
Reply 0

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Feb 3, 2022 | 08:07 AM
  #9  
For W204 the WIS calls to remove the starter.
I have asked few shops around here and I was told the starter does not need to be removed.

I am planning to do the work this weekend.
My plan is to put the car on the ramp but try to remove the air box to see if it's doable from top. Otherwise, I will remove the starter and go from there. My understanding is that I still need to remove the dust shields to catch oil from oil filter housing.
Reply 0
Feb 3, 2022 | 07:08 PM
  #10  
Quote: For W204 the WIS calls to remove the starter.
I have asked few shops around here and I was told the starter does not need to be removed.

I am planning to do the work this weekend.
My plan is to put the car on the ramp but try to remove the air box to see if it's doable from top. Otherwise, I will remove the starter and go from there. My understanding is that I still need to remove the dust shields to catch oil from oil filter housing.
Hi,
You can try from the top, but I think that the inlet manifold will be in the way. The starter motor is so easy to take off. Only 2 bolts and a couple of electrical wires. I like to disconnect the battery before doing that. But remember ONE thing before you do anything: Make sure that you can remove the hose clamp for the coolant inlet hose. The one that goes into the oil cooler. That's the most painful part of the whole job!
Good luck!
Reply 2
Feb 26, 2022 | 11:31 AM
  #11  
Hi, Milor,
Thank for your information, I will going to replace the gasket of oil cooler as I found some oil inside the coolant reservoir.
Reply 0
Mar 18, 2022 | 03:15 PM
  #12  
Quote: Hi,
You can try from the top, but I think that the inlet manifold will be in the way. The starter motor is so easy to take off. Only 2 bolts and a couple of electrical wires. I like to disconnect the battery before doing that. But remember ONE thing before you do anything: Make sure that you can remove the hose clamp for the coolant inlet hose. The one that goes into the oil cooler. That's the most painful part of the whole job!
Good luck!
Hi Milor, I appreciate the guide you sent above, it's helped me immensely so far in this repair. I just finished taking off the starter motor and can see the oil filter housing, five bolts, and coolant inlet hose. However, it looks like the coolant inlet hose has two clamps, one on the left side going into the oil cooler (red in picture below), and another on the right side (yellow in pic). It also seems like the hose passes through an opening on the backside of the oil filter housing.

As such I'm wondering if when removing the coolant inlet hose, would I need to undo both clamps, or only one of them?
Reply 0
Mar 23, 2022 | 04:25 PM
  #13  
Quote: Hi Milor, I appreciate the guide you sent above, it's helped me immensely so far in this repair. I just finished taking off the starter motor and can see the oil filter housing, five bolts, and coolant inlet hose. However, it looks like the coolant inlet hose has two clamps, one on the left side going into the oil cooler (red in picture below), and another on the right side (yellow in pic). It also seems like the hose passes through an opening on the backside of the oil filter housing.

As such I'm wondering if when removing the coolant inlet hose, would I need to undo both clamps, or only one of them?
Completed the job on a 2012 C250. The hose clamp circled in yellow was the one requiring removal. The left clamp in red is just a component of the entire oil filter housing part, and it doesn't need to be removed. To get the hose off, I approached it from the top with the manifold out. From this angle, I was able to use flexible hose pliers to loosen the clamp and pull the hose off (once the five oil filter housing bolts were already out). The hardest part, however, was reconnecting the hose. My hose clamp pliers didn't loosen the clamp enough, so for awhile I was having extreme difficulties getting the hose back on to the coolant pipe.

Eventually tried a Vise-Grip which considerably helped. This provided enough angle and force to loosen the clamp fully (more than the flexible clamp pliers allowed for), and I was finally able to slide the hose on. The trick is to use the Vise-Grip to lock the clamp into its maximally loosened position, and then slide the entire hose on to the pipe. This entire time, I recommend positioning the clamp on the end of the hose where it would naturally sit when the hose is in its normal position on the pipe. If using flexible hose clamp pliers make sure they open the clamp enough otherwise the hose won't slide on because of the tool limitation. Make sure to first get this hose on before bolting the oil filter housing. All in all tough but doable with the right tools and technique.
Reply 1
Jan 8, 2026 | 11:45 AM
  #14  
Using Tie Strap
Hi, what's your opinion on using a strong tie strap to remove the hose clamp?
Reply 0
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