In daily language, the phrase "crank up" means to start something mechanical or to increase the level/volume of something (e.g., "crank up the music"). If you'd like, I can provide more specific details on: How to fix a stiff engine crankshaft
Early automobiles required a starting crank (a "starting handle") to initiate the engine, a technique still used in some specialized or historic vehicles.
When combined with a connecting rod (conrod), it changes linear movement (like a piston moving up and down) into rotation.
Early models found in China dating back to the Western Han dynasty (202 BC - 9 AD) were used for winnowing fans and grinding grain.
