Originally Posted by
Max Angle
Most of the moisture is not getting in from the outside, it is water from the combustion process. Burning hydrocarbons mainly produces water and CO2 and because of the old design of these engines there is quite a lot of piston "blow by" and the combustion products end up in the crank case.
Any blow by would be scorching hot vapor and at pressure go right out the oil breather tube.
That’s what that tube is for.
Oil is being aerated by the crankshaft rshaft counterweights beating it to a froth.
Oil darkens over time because of the combustion byproducts.
Water? No.