Micah,

As was suggested by Tom O'Grady you might just want to reconsider what actually constitutes a "full" oil sump on your engine.  I have heard similar reports from countless pilots that suggested that when they filled the sump to the full mark on the dipstick that after an hour or two the oil level would have dropped by as much as two quarts and then would remain at that level for hours on end, or actually burn off at a much decreased rate (like it would take another 15-20 hours to get it to go down another 1/2 to one quart.)

We have a Lake Renegade here where I spend most of my time in Orlando with a Lyc TSIO-540 in it... full on the dip stick is 10 quarts.  FIll it to that level and fly for 2 hours and the level is down to 8.5 quarts with the 1.5 missing quarts found having been liberally applied to the nacelle and fuselage.  It takes another 10-12 hours of flight time to get it down to 8 quarts and it always maintains proper oil pressure readings at that level.  For normal operations we consider it topped up with 9 quarts on the stick and only fill it to the 10 quart mark after a complete oil and filter change, at which point we know there is going to be lots of cleanup required for the next several hours.

Just some thoughts.

   <Marv>
Micah Froese <micah@froese.com> wrote:
"""
I am getting oil on the belly of my Continental IO-500 powered Legacy. When
I shut down after a flight,
the breather tube makes a mess on the ground. Often ...snip...
"""