Leaking coolant on top of transmission c230k coupe

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Nov 21, 2020 | 06:31 PM
  #1  
So my c230k coupe 2002 had been leaking coolant on top of the transmission. I have no heat now and the car has this sweet smell. When I turn the heater on, that is when the coolant starts to leak on top of the transmission. How can I fix this?
here is the link to the video
https://www.reddit.com/r/mercedes_be...tm_name=iossmf
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Nov 21, 2020 | 06:32 PM
  #2  
Location
How can I fix it?
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Nov 23, 2020 | 01:52 AM
  #3  
Can't tell you too much as my car has a different engine.

Find the leak. Wipe everything up and then start the car and poke around. Maybe drive around for a minute or two as well.

Are you using factory approved coolant? Non approved coolants can do bad things (sludge, corrosion etc.) on these engines.

In the meantime, be sure not to run out of coolant. Looks like the leak has been going around for a while. Good luck.
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Nov 25, 2020 | 03:30 AM
  #4  
Quote: Can't tell you too much as my car has a different engine.

Find the leak. Wipe everything up and then start the car and poke around. Maybe drive around for a minute or two as well.

Are you using factory approved coolant? Non approved coolants can do bad things (sludge, corrosion etc.) on these engines.

In the meantime, be sure not to run out of coolant. Looks like the leak has been going around for a while. Good luck.
Yes, I'm using factory coolant, I got it from auto zone.
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Nov 25, 2020 | 08:19 PM
  #5  
I have a question, is 'heater core' the same as 'evaporator core' because ive just watched this video (edit* thanks to slammer for clearing it up as this isnt relevant to your coolant leak issue)

Also found this video showing the pipes that are in the engine bay the go into the cabin , that appear to be above the transmission
so there are pipes in the engine bay , and pipes inside the actual cabin.

So he removed the wipers and plastics revealing where those pipes enter... and he made a 'bypass' so no more coolant enters the cabin, i assume he has no heating anymore but atleast no coolant leak.

Someone elses problem will be yours one day so i'd like to know the solution myself, remove wipers/plastics and get a good look at those pipes
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Nov 25, 2020 | 08:28 PM
  #6  
Similar but different.

Heater core is filled with coolant and heats the air going into the cabin.

Evaporator core is filled with refrigerant and cools the air going into the cabin.

To be honest I can't figure out what would cause the evaporators to go bad on these cars other than maybe contaminants in the refrigerant.

The heater core can leak (usually at the O rings) but it's a relatively rare problem.

If the evaporator leaks, it needs to be replaced. That job is quite painful as you can see.
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