The intake system consists of those components that flow filtered air to the engine cylinders. See Figure 31553 .
The intake system consists of an air cleaner, air-to-air cooler, the compressor side of the turbocharger, valve cover/intake manifold and intake valves. During start up, the air is forced through the air cleaner by the atmospheric pressure.
1. Intake Manifold Pressure Port
2. Turbine Wheel
9. Crossover Pipe
3. Engine Exhaust Manifold
10. Charge Air Cooler
4. Exhaust Valve
11. Compressor Wheel
5. Intake Valve
12. Restriction Gage / Indicator Port
6. Engine Intake Manifold Valve Cover
13. Air Cleaner
Air Induction and Exhaust Systems
wheel faster causing the compressor impeller to turn faster and supply more air (greater boost) to the intake manifold. Conversely, with light engine load, the flow of exhaust gases decreases and less air is pumped into the intake manifold.
The air is cooled by a charge air cooler prior to entering the intake manifold. Air then flows into the combustion chamber where the proper amount of fuel is injected causing combustion to occur. Exhaust gases leave the cylinders through exhaust ports and the exhaust manifold. The turbocharger compressor side is part of the intake system and the turbine side is part of the exhaust system. See Figure 40275 .
Note: Effective January 2000, all Series 40E engines rated at 250 horsepower and above use an orange-colored, fiberglass-reinforced, formed silicone rubber air intake manifold elbow. This replaces the jointed, black rubber intake manifold elbow previously used.
1. Air Intake Manifold Elbow
4. Charge Cooler Air Inlet Pipe
2. Charge Cooler Air Outlet Pipe
3. Charge Cooler (Air-to-Air Intercooler)
Air Flow Through Air Induction System