Driving home from Houston on the open highway in the 1967 Citroen ID-19 the engine suddenly just stopped.
After trouble shooting it was determined that the cam lever had sheared off of the fuel pump and fallen into the crank case.
Luckily this model of the Citroen had a "priming lever" on the side of the fuel pump. I tied a piece of twine to the lever and ran it into the passenger side window. For the next 100 miles, my wife pulled the string about once every 2 seconds and we got home without further incident.