Fuel Injection Plunger and Barrel.

TM5-241O-237-34

back to fuel tank (l). This helps keep the fuel COO1 and free of air. Fuel

injection pump (9) gets fuel from the fuel manifold and pushes fuel at very high

pressure through fuel line (10) to fuel injection nozzle (11). The fuel injection

nozzle has very small holes in the tip that change the flow of fuel to a very fine

spray that gives good fuel combustion in the cylinder.

Fuel Injection Plunger and Barrel. The fuel injection plunger and barrel (9)

increases the pressure of the fuel and spends an exact amount of fuel to the fuel

injection nozzle (11). There is one fuel injection plunger and barrel for each

cylinder in the engine.

Fuel Injection Nozzle. The fuel injection nozzle goes through the cylinder head

into the combustion chamber. The fuel injection pump sends fuel with high

pressure to the fuel injection nozzle where the fuel is made into a fine spray

for good combustion.

seal (12) goes against the cylinder head and prevents leakage of compression

from the cylinder. Carbon dam (13) keeps carbon out of the bore in the cylinder

head for the nozzle.

Fuel with high pressure from the fuel injection pump goes into inlet passage

(14). Fuel then goes through filter screen (15) and into passage (16) to the

area below diameter (17) of valve (18). When the pressure of the fuel that

pushes against diameter (17) becomes greater than the force of spring (19),

valve (18) lifts up. When valve (18) lifts, the tip of the valve comes off of

the nozzle seat and the fuel will go through the nine 0.008 in. orifices (20)

into the combustion chamber.

The injection of fuel continues until the pressure of fuel against diameter (17)

becomes less than the force of spring (19). With less pressure against diameter

(17), spring (19) pushes valve (18) against the nozzle seat and stops the flow

of fuel to the combustion chamber.

Fuel Transfer Pump. The fuel transfer pump is a piston pump that is moved by a

cam (eccentric) on the camshaft for the fuel injection pump. The transfer pump

is located on the bottom side of the fuel injection pump housing.

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