Would anybody happen to know what this part is?
#1
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I'm not sure if this is where my coolant leak is coming from, but the bottom half of it is damp from what I believe is the coolant I've lost. It's circled in yellow in the attached picture and has a tube/pipe that runs to the driver's side of the engine bay.
Any help is greatly appreciated.
Thanks!
![Twoup](https://5series.net/forums/images/smilies/imported/twoup.gif)
Any help is greatly appreciated.
Thanks!
![Twoup](https://5series.net/forums/images/smilies/imported/twoup.gif)
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thats the vacuum pump, and they are known for leaking oil.
i had a mysterious coolant leak also. check your lower radiator hose where it attaches to the radiator, there is a coolant sensor that plugs in there, and the o-ring for it is known to leak. check while car is warm, since the leak is slow enough, that it evaporates and doesnt hit the ground.
i had a mysterious coolant leak also. check your lower radiator hose where it attaches to the radiator, there is a coolant sensor that plugs in there, and the o-ring for it is known to leak. check while car is warm, since the leak is slow enough, that it evaporates and doesnt hit the ground.
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Looks like there is an oring that seals the pump to the upper timing cover. This might be cause of an oil leak.
#7
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I just Googled that after reading your reply. Looks like I'll have to order an o-ring kit for that one, too. Thanks again!
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Also check the coolant expansion tank vent pipe that runs along the top of the radiator. The hard plastic portion of the pipe develops cracks. I just replaced mine on my 08 550i, because it suddenly failed.
#9
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Been there, done that on my 05. fixed it by replacing the 05 with a MY 2010 Msport
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