Series 60 EGR

Section 3.3 EGR Mode

Section 3.3
EGR Mode

Figure "Coolant Flow through the EGR Cooler" illustrates EGR coolant flow.‪

Exhaust gas enters the EGR cooler at high temperatures and is cooled by the engine coolant system to increase the density of the gas.‪

Click to see this graphic in a separate window

Figure 1. Coolant Flow through the EGR Cooler

See Figure "EGR Measurement" for EGR measurement.‪

Once exhaust gases begin flow through the EGR cooler and past the venturi, pressure levels are measured from the two venturi taps or ports. The delta pressure measurement, in conjunction with the EGR temperature determines the EGR flow rate.‪

Click to see this graphic in a separate window

Figure 2. EGR Measurement

See Figure "VNT Control Flow " for VNT control flow.‪

The VNT turbocharger is the mechanism used to change the EGR rate‪

The VNT is controlled via the DDEC PWM #4, see Figure "EGR Valve and VNT Control System" , which regulates the air pressure to change the VNT vane position.‪

Click to see this graphic in a separate window

Figure 3. EGR Valve and VNT Control System

Changes to the vane position, either closing or opening, result in an increase or decrease to the EGR flow rate. See Figure "VNT Control Flow " .‪

Click to see this graphic in a separate window

Red = Exhaust Gas‪

Yellow= Vehicle Air (VPODs)‪

Orange= Cooled Exhaust Gas‪

Green= Coolant Flow‪

Figure 4. VNT Control Flow


Series 60 EGR Technician's Manual - 7SE60
Generated on 10-13-2008

Leave a Reply

Your email address will not be published. Required fields are marked *