I've been flying my Rambler with a Saito 72 for about 6 months now and it is well broken in with probably over four gallons through it. I have a fuel line connected to the crankcase vent and I've noticed, (since new) that it is always very dry and very clean indicating that little to no fuel is exiting. The engine runs perfectly so I'm not worried about but, how much residue should be leaving the crankcase?