 Tractors and heavy equipment were often multifuel in the 1920s through 1940s, running spark-ignition and low-compression engines.Thus many farm tractors of the era could burn gasoline, alcohol, kerosene, and any light grade of fuel oil such as diesel fuel, heating oil, or tractor vaporising oil, according to whichever was most affordable in any region at any given time.On U.S. farms during this era, the name "distillate" often referred to any of the aforementioned light fuel oils.