• Diesel engines are mostly used in vehicles, such as trains and trucks.diesel engine image by leafy from Fotolia.com
  
  Diesel engines are like gasoline engines in that they burn materials and convert them into energy. This energy then powers the vehicle by moving pistons up and down, causing the vehicle's crankshaft to turn, according to the U.S. Department of Energy. Diesel engines compress and heat the air that is pumped into the engine, causing the fuel in its cylinders to ignite.
  
  

Block Casting

• The cylinder of the diesel engine is important as this is where combustion occurs. One kind of cylinder used by the diesel engine is bored into a block casting, according to Engineer's Edge. The cylinder confines combustible gases so they can be ignited to drive the piston.
  
  

Machined Steel Sleeve

• Another kind of cylinder found in the diesel engine is a machined steel sleeve pressed into a block casting, forming a cylinder. This kind of cylinder has sleeves that are either wet or dry. Wet sleeves come into contact with the engine's coolant, according to Engineer's Edge. Dry sleeves are surrounded by the metal of the block, keeping it away from the coolant. The cylinders are arranged either in a V or in a row.
  
  

Electronic Control System

• The fuel injector operates by allowing pressure to lift a needle valve from a seat. The fuel enters the diesel engine at a high velocity, according to CDX Online ETextbook. Fuel injection is often controlled by an electronic control system that measures the amount of diesel fuel that should be injected into the engine and then releases the fuel in controlled sprays.
  
  

Diesel Injection System

• Another kind of diesel injection is the common-rail system. Controlled quantities of atomized fuel -- which is fuel in the form of a mist -- are released in the engine, according to CDX Online ETextbook. These controlled amounts help improve fuel economy, reduce exhaust emissions and decrease noise.
  
  

HEUI Diesel Injection System

• The HEUI diesel injection system is powered by hydraulics and controlled by an electronic system, according to CDX Online ETextbook. The hydraulic system draws fuel from the tank with a fuel pump.