How A Diesel Pump Works
1998-5-8How a diesel pump works is with two primary goals. Diesel pumps deliver the fuel in a timed manner that allows the engine to run smoothly. Different speeds require a different amount of fuel to provide the proper power. Injection pumps control these levels as well. To meet new emissions standards, mechanical pumps are slowly being replaced by alternatives. These alternatives allow for higher compression ratios. The tiny droplets produced by the mechanical pumps are being replaced by a very fine mist, which allows for more exact control of injection volumes. There are several alternatives to the traditional injection pump.
Inline injection diesel pumps force a specific amount of fuel through cylinders to the compression chamber. How a diesel pump works is that each cylinder has its own pump. They are usually connected to the crankshaft or camshaft. Some are connected by gears, others by belts or chains, depending on the design of the engine. The pump can vary the timing, based on need. The original, mechanical pumps were able to deliver 3,000 to 5,000 per square inch (psi) of injection pressure. However, some of the new, electrical versions can deliver up to 18,000 psi.
Distribution or rotary injection diesel pumps have only one pump that rotates between the cylinders, as opposed to one pump for each. How a diesel pump works is that there is a small sinning motor that connects to the cylinders via several different ports on a distributor head. There are two primary advantages to this type of injection pump. The first is that each burst of fuel to the engine is exactly the same, which keeps power levels even. The second is that the overall size is smaller, with fewer moving parts than inline pumps. The pressure produced ranges from 6,700 to 17,000, based on engine design.
Unit injectors were created to solve many of the issues created by the original design of the numerous lines connecting the inline injection diesel pumps. The result is a compact unit in which the pump's plunger or piston creates a high pressure applied directly to the engine. The plunger and injector are one unit that both delivers and distributes the fuel to the combustion chamber. How a diesel pump works for common rail injection systems is that much of the pump's original job delivering and distributing, based on need is transferred. Though it still delivers pressure, most of the fuel quantity and delivery is taken over by the injectors
Inline injection diesel pumps force a specific amount of fuel through cylinders to the compression chamber. How a diesel pump works is that each cylinder has its own pump. They are usually connected to the crankshaft or camshaft. Some are connected by gears, others by belts or chains, depending on the design of the engine. The pump can vary the timing, based on need. The original, mechanical pumps were able to deliver 3,000 to 5,000 per square inch (psi) of injection pressure. However, some of the new, electrical versions can deliver up to 18,000 psi.
Distribution or rotary injection diesel pumps have only one pump that rotates between the cylinders, as opposed to one pump for each. How a diesel pump works is that there is a small sinning motor that connects to the cylinders via several different ports on a distributor head. There are two primary advantages to this type of injection pump. The first is that each burst of fuel to the engine is exactly the same, which keeps power levels even. The second is that the overall size is smaller, with fewer moving parts than inline pumps. The pressure produced ranges from 6,700 to 17,000, based on engine design.
Unit injectors were created to solve many of the issues created by the original design of the numerous lines connecting the inline injection diesel pumps. The result is a compact unit in which the pump's plunger or piston creates a high pressure applied directly to the engine. The plunger and injector are one unit that both delivers and distributes the fuel to the combustion chamber. How a diesel pump works for common rail injection systems is that much of the pump's original job delivering and distributing, based on need is transferred. Though it still delivers pressure, most of the fuel quantity and delivery is taken over by the injectors