[robc1976]

Originally Posted by drwharton85

Well worked on it today for several hours and several lessons learned. 1) after market down pipes can only be removed by unbolting the mounts and jaking the engine up a couple inches, which for me was a waste of time because only the front turbo was leaking. Everyone seems to think the front turbo is the killer NO THE BACK IS BECAUSE YOU HAVE TO REMOVE SO MUCH SH**. the front can easily be done by draining the coolant and removing the 8" or so U shape coolant line, if it is the turbo oil return line anyways, which was my case. After spending hours of wasted time, which now I know I could cut down to less than 2, the oil return line still freaking leaks, I think maybe the line is damaged some how because it is not getting a proper seal, I guess I will have to look into that some more.

Engine doesn't need to be moved at all on a 335i (maybe Xi) to get down pipes out. The oil lines run top to bottom and you will need to replace the gasket as seen below after reference pics:



Some reference pics of the lines

Front turbo front:



Front turbo rear:



Rear turbo front:



Rear turbo rear:




Oil line can be very tight, basically hard to hold in place with gasket while lining up holes, bolt in one side with the gasket on....then slide gasket over and tighten the other side:




Top oil lines join together in between turbo and the 2 way fitting... 1 side joins the lines together and the otherside pushes into the block with a o-ring seal: