Dylan Smith wrote:

A little oil, when smeared over the side of the aircraft, goes a long
way. I once did a stupid pilot trick (was interrupted during my preflight and
forgot to replace the oil filler cap/dipstick on the C140!) and on
landing a short time later discovered what looked like a gallon of oil
coating the side and belly of the aircraft. However, not much had
actually been blown out the engine. Fortunately, the cap/dipstick was
still where this idiot had left it - on top of the engine!


I did this on a Continetal powered 172. The dipstick was separate
from the oil filler neck (much bigger opening). I lost 2 quarts on a
3 hr. flight and the plane was covered from nose to tail and dripping
all over my tiedown. Like you, I opened the cowl and found the cap
right where I'd left it. Sitting on top of the battery box. It was
pretty embarrasing, as my IA had come out to see what happened after
seeing me taxi past.

A few years later (same plane) I landed in the middle of nowhere in
Nevada and the FBO lady came out and was excitedly pointing at my
plane. When I got out and saw oil all down the side, I couldn't
believe I'd done it again. As it turned out, I didn't. This time, the
entire oil filler neck had departed the engine somewhere over Idaho or
Nevada. It was press-fit into the engine and had come loose over the
decades. This time I lost 2 1/2 quarts and had to wait 3 days for the
part.

John Galban=====N4BQ (PA28-180)