Expansion cooling tank. Return line
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Joined: Jun 2025
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2012 W166 350
Expansion cooling tank. Return line
Hello everyone, I'm needing some advice here.
A couple of months ago I replaced my expansion cooling tank's return line as it was leaking from the end connected to the radiator and went with an OEM part. When replacing the line, the end connected to the expansion tank barely had any of the fitting left as the end of it has become brittle so now, because the return line is not fully locked into place I now have a very small leak so I have to top it off every other week as I get the warning message on the cluster. I obviously do not see the need of replacing a whole expansion tank for such a small issue so my question is, will using a universal coolant overflow hose on clamps work or do I really need to replace the whole thing? Any suggestions?
A couple of months ago I replaced my expansion cooling tank's return line as it was leaking from the end connected to the radiator and went with an OEM part. When replacing the line, the end connected to the expansion tank barely had any of the fitting left as the end of it has become brittle so now, because the return line is not fully locked into place I now have a very small leak so I have to top it off every other week as I get the warning message on the cluster. I obviously do not see the need of replacing a whole expansion tank for such a small issue so my question is, will using a universal coolant overflow hose on clamps work or do I really need to replace the whole thing? Any suggestions?
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Joined: Jun 2021
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From: Fleriduh
W212 E63S Wagon - GSL580 - E63 - E350 - C300
The entire expansion tank (the whole thing) is low cost and yes...considered regular maintaince. From there, know that your other (many) plastic cooling connectors are also brittle.
