The Stovebolt Site Forums The Shop Area Engine Shop Milky oil at draft tube

I had the valve cover with slots, (which I squooshed and brazed shut in an attempt to cut down on an imagined dust infiltration problem) and a vented fill cap. My experience with the same truck for the last 30 years is when it gets cold out there will be milky oil around the vent, don't squoosh the slots, that will make it even worse. When I was driving from sandiego to Montana, in the morning it would be clear, then the first fillup it would have the milky oil around the filler cap, the second fillup would be less, and finally sometime after noon, it would be almost completely clear, but it took at least 4 hours. But it was nearly strictly in the fill cap area. And since that engine lasted some 31 years, I wouldn't worry about it.