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Old 02-19-2013, 09:51 AM
avoisin avoisin is offline
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Location: Oregon
Join Date: Feb 2013
Posts: 11
Mein Auto: 2004 X3 2.5i
Persistant cooling leak from expansion tank

I've been plagued in the last few weeks with a coolant leak that just refuses to go away. I recently had to change out the heating/cooling thermostat underneath the expansion tank, and now I can't stop a leak from that area.

Best I can tell, the leak is coming from the two holes at the bottom of the expansion tank, where they sit on the mount. One has a pin clip to hold it in place, the other just sits by friction. It's the latter that seems to be wedging just a bit loose, and causing a slow, small drip. The part is the "Cooling Water Connector" that I just cannot get to stay flush after assembly. You can see it here on the great DIY:

DIY Cooling Replace, post #14, picture #5. It just wiggles around too much in the housing, there's probably a good 1/8" of play at least.

I've tried simply reseating, adding some silicone putty, but nothing I can think of will get that connector to sit flush consistently. Only other thing that comes to mind is a real adhesive or something to truly bond that connector/mount area to the tank, but I really don't want to resort to that.

Anyone have ideas??
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