Detroit Diesel Series 60 EGR Technician Manual page 121

SERIES 60 EGR TECHNICIAN'S MANUAL
Figure 8-19 Charge Air Cooler
Variable Nozzle Turbocharger
Variable nozzle turbocharger (VNT), see Figure 8-20, uses an actuator to regulate and control
turbine vanes. There is no wastegate with this system. The VNT actuator is mounted on a bracket
attached to the turbocharger and receives air pressure from engine-mounted VPOD. The VNT
actuator connects via a rod to the pin joint of the turbine external arm. Rotation of the external
arm simultaneously rotates several pivoting nozzle vanes positioned inside the turbine housing at
the outer periphery of the turbine wheel. This adjusts turbocharger speed, boost and EGR flow in
accordance with DDEC engine management control.
NOTE:
VNT actuator is spring loaded. If air pressure is lost the actuator will open the VNT
vanes resulting in low/no boost.
8-21
All information subject to change without notice. (Rev. June 2005)
7SE60 0506 Copyright © 2005 DETROIT DIESEL CORPORATION