Operation

6.7L DIESEL




6.7L TURBOCHARGER





The turbocharger is water cooled and lubricated by engine oil that is pressurized, cooled, and filtered. The oil is delivered to the turbocharger by a supply line that is tapped into the oil filter head. The oil travels into the bearing housing, where it lubricates the shaft and bearings. A return pipe at the bottom of the bearing housing, routes the engine oil back to the crankcase.

Exhaust gas enters the turbine section of the turbocharger as it leaves the combustion chamber. Heat and pressure are extracted from the exhaust gas and cause the turbine to rotate. The turbine is connected by shaft to the compressor section of the turbocharger. The rotating compressor draws in inlet air, compresses it and sends the compressed air through the Charge Air Cooler to the engine.

The Variable Geometry Turbocharger (VGT) uses a one piece sliding nozzle that moves continuously to vary the power of turbine and the amount of air delivered to the engine. This allows turbine power to be set to provide just enough energy to drive the compressor at the desired boost level in all engine operating modes.

Turbine power level changes are achieved by varying the position of the nozzle ring in relation to a set of guide vanes that control the flow through the turbine. An electrically controlled actuator positions the sliding nozzle over the guide vanes.

Letting the engine idle after extended operation allows the turbine housing to cool to normal operating temperature. The following chart should be used as a guide in determining the amount of engine idle time required to sufficiently cool down the turbocharger before shut down, depending upon the type of driving and the amount of cargo.

Turbo Charger "Cool Down" Chart: