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Yes, I have both main front pinion seal leaking and camchest puke and this is the reason I am asking the questions. Making the oil tank breathe helped but not totally stopped it.
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Stephen,

From reading your posts over the last couple of years, I believe you are conflating a couple of topics: wet sumping and crankcase breathing. They are not intrinsically related, though a sump full of oil can cause short term (as in seconds, not minutes) breathing issues. But once the engine has been running for a few seconds, the sump is scavenged of oil, the excess pressure caused by a crankcase full of oil is gone and the (excess oil in the crankcase related) leaks will cease.

Let your machine set for a few weeks, then using the drain plug on the bottom of the engine, drain and measure the amount of oil that was in the crankcase. If it's a couple of quarts or less, you do not have a wet sumping issue worth worrying about. I.e. that would be reasonably normal for a dry sump engine design with a remote oil reservoir that sits much higher than the oil pump through which oil eventually leaks into the sump.

If your engine leaks (not weeps, but leaks) from the crank seals and camchest breather while running then it is not a wet sump issue, but is rather a crankcase breathing issue.

If it's weeping only from the crank seals, then it's either bad seals or worn/poorly machined sealing surfaces on the crank.

As I have written much about the x-wedge breather system previously on this forum I will not repeat all of that, but will summarize by saying there is nothing inherently wrong with the factory breathing system, and venting the crankcase to atmosphere is not an improvement nor is it in any way necessary.

But if your leaks were diminished somewhat by the change to your elaborate vented to atmosphere breather system, that would indicate to me your engine may be suffering from excessive combustion blow-by, typically due to worn piston rings, or rings which glazed before being fully seated. I would suggest you perform a leak down test on your engine to see if that's the case.


Steve
Late 2012 M3W