Piper Cherokee oil usage??

[Mark White]

I have a 0-360 in my 180 and when I change oil and filter I install a new filter and add 6 quarts and leak test it before re cowling the engine. If there are no leaks on goes the cowling and then the next morning I check the oil and it will show 6 and 1/2 quarts. I have a quick drain and I normally let it sit draining overnight. Point is all oil is not drained because it's almost impossible. If you are checking for an accurate oil consumption I would suggest you start at a lower than 8 quart level. I, like most, run mine at 6 quarts and add at 5 which I have marked on my dipstick. Most are graduated in 2 quart increments. If you say to me it drops quickly from 8 quarts I would surly believe you but that's fairly normal and that's why most folks don't service to 8 quarts. Also if you are taking trips mostly less than an hour your consumption will be higher in my experience. Bring your oil level to six quarts and see what you consumption is on fewer short flights and see what you get. I have Millennium cylinders and 390 hours and 10 years SMOH and I use about 1 quart per 5 hours. I have 75 to 78 compression on the cylinders and have borescoped the cylinders and the valves look good and there is still crosshatch pattern present so I will continue to fly until something dramatic changes. Short of pulling a cylinder the only other thing I would look for is valve guides pushing an inordinate amount of oil which you can detect by using a borescope to look at the guides with the valve open.