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I have found some strange oil spots. I have the top mounted oil cooler and have one small leak at the rear right pushrod tube and I found oil blown onto the fuel filler neck. It is only a few drops. I think it is being blown through the oil cooler from the oil check dipstick. My dipstick just sits over the neck. It does not fit tight at all. There is no indication of leaking anywhere on the top of the engine or the oil cooler. Has anyone else seen a leak like this. Also I put in a little more than 2.75 quarts on the last oil change. But it was less than 3 quarts. That said I have the Sonex oil separator and the return line is connected to the sump plate. So some of the oil goes I to the return hose.

If there is any back pressure at all inside the crankcase oil will blow out around the crankshaft at the prop hub. I once made the mistake of using too small a breather line and I had oil every where.

Im not getting anything out of the prop hub. I used the recommended hoses and fittings for the breather. I will keep an eye and take a better look at the prop hub.

Some of us go so far as to install breather vents in the valve covers and plum them to the bottom of the cowl just as with the the crank case breather.