2004 107ci, oil leaking from crankcase breather

Mr. Wright

Guru
Supporting Member
This is normal. When it sits, the oil will drain from the tank, to the bottom of the engine. This is called sumping. When you start the engine, the oil pump can not work fast enough to pump the oil back to the tank, and the pressure, caused by the pistons, pushes the oil out of the breather vent.
Just run the engine till it clears out, then top off the oil, and clean up the mess when it's done.
 

bdm7250

Guru
Supporting Member
This is normal. When it sits, the oil will drain from the tank, to the bottom of the engine. This is called sumping. When you start the engine, the oil pump can not work fast enough to pump the oil back to the tank, and the pressure, caused by the pistons, pushes the oil out of the breather vent.
Just run the engine till it clears out, then top off the oil, and clean up the mess when it's done.
:agree: Yup.
 

Sven

Well-Known Member
Oh no, a Svennieism.... Intertwine your fingers with both hands. See the air gap between fingers? That's how oil is captured and the gears spin to bring that much to cause pressure. But sitting... take one drop and see it zigzag thru your fingers and down to the crankcase. That's like saying... take 14.7 pounds is a bag of sand placed on top of the oil in the tank. There is the pressure on that one drop [after drop] going zigzag onto the garage floor after months of sitting.
 
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