Turbocharger: Description and Operation

Turbocharger System:

PURPOSE
The Turbocharger is a cast iron housing consisting of a turbine rotor, center shaft with support bearings, and an impeller rotor (wheel).


OPERATION
As exhaust gas is forced from the engine into the turbine inlet of the turbo, the turbine rotor begins to rotate counter clockwise. Even at idle, the turbine is spinning at approximately 20,000 rpm and increases with engine speed. The turbine is directly connected to the impeller wheel by the center shaft, which causes the impeller to rotate at the same speed as the turbine, however the direction of revolution is reversed. As exhaust gas is spent by the turbo, the gasses are sent from the center port to the exhaust pipe, while the impeller draws air into itself through the center port from the Airflow Meter.

The center shaft rotates on two full-floating bearings, that are lubricated by the engine oil pump with crankcase oil. Use only motor oil rated for turbocharger use. The turbo has coolant passages that receive engine coolant via flexible metal lines connected to the engine cooling system. The turbo is designed to pressurize the intake system to 4.8 - 7.5 psi before the Wastegate Valve relieves the pressure. The turbocharger is located on the RH side of the engine, and also provides a mounting for the wastegate actuator and wastegate valve.