Changed the oil in the 285 yesterday.

Now I'm confused. With a filter change, the crankcase holds ten quarts of oil... I emptied two gallon jugs and two quarts of Shell Rimula into it.

Nothing on the dipstip.

Poured two more quarts.

Now it's showing on the very bottom of the dipstick.

Poured in two more quarts.

Now it's up in the normal range, but still not full.

According to my calculations, I now have 14 quarts of oil in it.... and it's still not full?

Has someone changed standard weights and measures lately?

Or, as it is oft claimed, am I just an idiot?