uring the intake stroke. Air alone is compressed during the compression stroke. The Diesel fuel oil is injected or sprayed into the cylinder at the end of the compression stroke. In Diesel engines, compression ratios are as high as 22.5 to I and provide pressures of 500psi at the end of the compression stroke. Through the compression process, the air can be heated up 1000 degrees F. This temperature is high enough to spontaneously ignite the fuel as it is injected into the cylinder. The high pressure of the explosion forces the piston down as in the gasoline engine....
