from no load to full load by rotation of the plunger in
3-18. Fuel lnjector
(4) Figure 3-30 illustrates the phases of fuel injec-
(1) The fuel injector (fig. 3-28) is a lightweight
tor operation by vertical travel of the injector plunger.
compact unit which enables quick easy starting direct-
(5) The continuous fuel flow through the injector
ly on diesel fuel and permits the use of a simple open
serves, in addition to preventing air pockets in the fuel
type combustion chamber. The simplicity of design
system, as a coolant for those injector parts subjected
and operation provides for simplified controls and
to high combustion temperatures.
(6) Each fuel injector control rack (fig. 3-28) is
(2) The fuel injector performs four functions:
actuated by a lever on the injector control tube which,
(a) Creates the high fuel pressure required for
in turn, is connected to the governor by means of a fuel
rod. These levers can be adjusted independently on the
(b) Meters and injects fuel to the exact amount
control tube, thus permitting a uniform setting of all
required to handle the load.
(c) Atomizes the fuel for mixing with the air in
the combustion chamber.
(1) Remove the rocker arm cover (para 3-16).
(d) Permits continuous fuel flow.
(2) Remove the fuel supply and fuel return lines
(3) Metering of fuel is accomplished by an upper
from the fuel injector and fuel connectors.
and lower helix machined in the lower end of the injec-
tor plunger, Figure 3-29 illustrates the fuel metering