Ran out of fuel in a friend's W123 (bad fuel gauge). I thought, "these things will run on the fumes of an oily rag and there is at least a gallon of motor oil in the trunk".
I dumped it in, not thinking it was synthetic, (it was dark and cold). Engine started right up after a few pumps of the primer. Then the bad......runs rough, slows down and stalls. After many tries still stalls/no power.
Hiked several miles to a station that sold diesel and got 5 gallons. Dumped it in the tank and it still took a half an hour of primer pumping, starting and stalling before the synthetic oil was diluted enough for the car to drive above a walking pace. Finally and fairly suddnly, it began to run like normal and I made it home.