TM 5-3810-300-24&P-3
2.1.1
FUEL INJECTOR (NEEDLE VALVE)
The fuel injector (Figs. I and 2) is a lightweight compact
1. Creates the high fuel pressure required for efficient
unit which enables quick, easy starting directly on diesel
injection.
fuel and permits the use of a simple open type
2. Meters and injects the exact amount of fuel required
combustion chamber. The simplicity of design and
to handle the load.
operation provides for simplified controls and easy
adjustment. No high pressure fuel lines or complicated
3. Atomizes the fuel for mixing with the air in the
air-fuel mixing or vaporizing devices are required.
combustion chamber.
The fuel injector performs four functions:
4. 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
cylinder.
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
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