[dsjr2006]

It's been a fun couple of weeks with the E90. Started out 2 weeks when I got a low coolant warning. Didn't see a leak so I topped it up and no issues for a few days. About a week later I get the same message so I top it off with distilled water and drive the car to get it warm. When I stopped I found this:



Full Size:
https://www.dropbox.com/s/xiucqpvbsb...%2036.jpg?dl=0
https://www.dropbox.com/s/emgm8n4prl...%2028.jpg?dl=0

========

Decided to go ahead a replaced the water pump, thermostat, and the oil filter housing gasket that had been leaking. What I didn't realize is how much of a mess than oil filter housing gasket leak had caused. I also think I found the source of the coolant link in the thermostat.

Pictures of Mess from leaks:

Full-size: https://www.dropbox.com/s/rzjz9hwokn...%2000.jpg?dl=0

https://www.dropbox.com/s/xe0v8qexbj...%2054.jpg?dl=0

Thermostat crack??


https://www.dropbox.com/s/ppwkyn1z6s...81%29.jpg?dl=0

[dsjr2006]

I'm hoping it really was just the oil filter housing gasket getting worse that caused the coolant and oil to mix because under the engine oil cap I found this surprise:



Full-size:
https://www.dropbox.com/s/ms1na754br...%2043.jpg?dl=0
https://www.dropbox.com/s/0onfjbp841...%2018.jpg?dl=0

I cleaned it up and continued with replacing the Oil Filter Housing Gasket. The gasket looked pretty rough and it left quite a mess. The connection coolant pipe coming from the front of the engine broke on me like it did for many others so I ordered a replacement from eBay the replaces the plastic piece with aluminum.

Broken fitting and location:



https://www.dropbox.com/s/nbc1ext0f9...%2059.jpg?dl=0
https://www.dropbox.com/s/rgf8yj1zyq...%2019.jpg?dl=0

Replacement fitting: https://www.ebay.com/itm/253020416033

Gaskets:

https://www.dropbox.com/s/ix9c33lql3...%2014.jpg?dl=0

[dsjr2006]

Cleaned everything up, replace serpentine belt, tensioner, pulleys, and now just waiting on the coolant fitting to arrive so I can prime the cooling system and test it out. And that brings me to my next issue to tackle: http://www.e90post.com/forums/showthread.php?t=1461392 which I'm hoping is just a valve cover gasket.

I'm hoping not to see anymore oil and coolant mixing after replacing the oil filter housing gasket, water pump, thermostat, oil and coolant. Anyone else have this issue?

[juld0zer]

You'd want to run a cooling system flush several times and change the engine oil and filter too.

You may need to replace other rubber hoses in the future and any quick release couplings may have swollen orings from tge oil

[feuer]

You should have not touch that coolant line. I hope that you have ordered aluminum flange replacement. I strongly advise you that you replace the belt too. Oil and coolant eat the rubber. Belt brakes. Enters the engine.....

[dleccord]

Why is BMW gasket so inferior?!!

[dsjr2006]

Originally Posted by feuer

You should have not touch that coolant line. I hope that you have ordered aluminum flange replacement. I strongly advise you that you replace the belt too. Oil and coolant eat the rubber. Belt brakes. Enters the engine.....

I had to remove it, which is how it broke. If you read my post you would see that I ordered an aluminum replacement as well as changed the belts and pulleys.

[feuer]

Originally Posted by dsjr2006

I had to remove it, which is how it broke. If you read my post you would see that I ordered an aluminum replacement as well as changed the belts and pulleys.

You don't remove that in order to remove the OFH. I see post #3 now on belt and tensioner.

[bmuum3]

I just did my OFHG and also removed the hose. Mine was in great shape and didn't break. Looking back I could have left it in, but made getting that torx out so much easier.

[dsjr2006]

Originally Posted by feuer

You don't remove that in order to remove the OFH. I see post #3 now on belt and tensioner.

It makes it easier and I wanted to clean under it because of the oil dripping from the leak.