FUEL INJECTOR (Needle Valve)
The fuel injector (Figs. 1 and 2) is a lightweight
Creates the high fuel pressure required for
compact unit which enables quick, easy starting directly
on diesel fuel and permits the use of a simple open type
Meters and injects the exact amount of fuel
operation provides for simplified controls and easy
required to handle the load.
adjustment. No high pressure fuel lines or complicated
air-fuel mixing or vaporizing devices are required.
Atomizes the fuel for mixing with the air in the
The fuel injector performs four functions:
Permits continuous fuel flow.
Combustion required for satisfactory engine operation is
obtained by injecting, under pressure, a small quantity of
accurately metered and finely atomized fuel oil into the
Metering of the fuel is accomplished by an upper and
lower helix machined in the lower end of the injector
plunger. Figure 3 illustrates the fuel metering from no-
load to full-load by rotation of the plunger in the bushing.
Fig. 1. Fuel Injector Assembly
Fig. 2. Cutaway View of Fuel Injector