User Manual

ManualsBrandsPerkins Engine ManualsOther854F-E34T, 854E-E34TA, 854F-E34TA Systems Operation Testing and Adjusting

Air is drawn in through the air cleaner into the air inlet

of the turbocharger by the turbocharger compressor

wheel. The air is compressed to a pressure of about

150 kPa (22 psi) and the compression heats the air

to about 120° C (248° F) before the air is forced to

the aftercooler. As the air flows through the

aftercooler the temperature of the compressed air

lowers to about 55° C (131° F). Cooling of the inlet

air assists the combustion efficiency of the engine.

Increased combustion efficiency helps achieve the

following benefits:

• Lower fuel consumption

• Increased power output

• Reduced NOx emission

• Reduced particulate emission

From the aftercooler, air is forced into the inlet

manifold. Air flow from the inlet manifold to the

cylinders is controlled by inlet valves. There is one

inlet valve and one exhaust valve for each cylinder.

The inlet valve opens when the piston moves down

on the intake stroke. When the inlet valve opens,

cooled compressed air from the inlet port is forced

into the cylinder. The complete cycle consists of four

strokes:

• Inlet

• Compression

• Power

• Exhaust

On the compression stroke, the piston moves back

up the cylinder and the inlet valve closes. The cool

compressed air is compressed further. This

additional compression generates more heat.

Note: If the cold starting system is operating, the

glow plugs will also heat the air in the cylinder.

Just before the piston reaches the top center (TC)

position, the ECM operates the electronic unit

injector. Fuel is injected into the cylinder. The air/fuel

mixture ignites. The ignition of the gases initiates the

power stroke. Both the inlet and the exhaust valves

are closed and the expanding gases force the piston

downward toward the bottom center (BC) position.

From the BC position, the piston moves upward. This

initiates the exhaust stroke. The exhaust valve

opens. The exhaust gases are forced through the

open exhaust valve into the exhaust manifold.

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Engine Operation

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