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Loaded Question - Milky Oil From Crankcase Vent After Shutdown?

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Well-Known Member
Supporting Member
May 9, 2024
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I appreciate all the knowledge sharing on this forum. You guys are great!

Okay, loaded question. I’ve noticed a few drops of chocolate milk colored oil dripping out the crankcase vent after shutdown. After a few drops, normal colored oil drips and dilutes it.

At first I thought perhaps some condensation in the crankcase and hasn’t ran enough. I am still seeing it after about 7 hours of flying.

Dipstick looks great, no signs of anything but good oil. Running Shell W100 Plus. Right at 4 qts and oil blow is minimal. I’ve added maybe 1/3 quart for 7 hours flying time

What are your thoughts on what this could be?

Pictures below - thanks all!


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