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Old 01-18-2013, 01:55 PM
awdrev awdrev is offline
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Location: Maryland
Join Date: Dec 2012
Posts: 82
Mein Auto: 2004 BMW X3 3.0 Auto Tran
Originally Posted by mlukas161 View Post
Did you replace the expansion tank cap with a new one or reuse the old one?
Update: I think the leak was because of excessive coolant. I got the new cap and I took the old one out.

The first thing I noticed was that the needle was at its highest point no matter what. Meaning, that it doesn't take much for the expansion tank to be full.

I ended up replacing the cap anyways because I noticed that the new cap had two rubber seals that were in far better condition that the old cap. I believe the leak near the tank is now gone.

However, I notice a very minuscule coolant leak from one of the thermostat hoses. I haven't been able to check exactly where it's coming from but if you are facing the car, I think it's the hose LEFT from the thermostat. (If you are sitting in the car it would be the hose that is connected on the passenger side)... It's not a major leak but something to keep an eye on.

I am predicting I will have to do the full engine cooling system maintenance in the spring/summer. I just gotta get the parts first, part of me does NOT want to replace the radiator though. It's too much work imo to take it out but I haven't decided.
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