3508B Industrial Engines Caterpillar

There are two turbochargers that are used on the rear of the engine. The turbine side of each turbocharger is connected to the respective exhaust manifold. The compressor side of each turbocharger is connected by pipes to the aftercooler housing. The turbocharger is supported by the central exhaust elbow.

Illustration 1	g00322583
Turbochargers (Typical Example) (1) Turbocharger (2) Oil drain line (3) Oil supply line

Illustration 2	g00307853
(4) Compressor wheel (5) Bearing (6) Oil inlet port (7) Bearing (8) Turbine housing (9) Turbine wheel (10) Air inlet (11) Oil outlet port

The exhaust gases go into the exhaust inlet of the turbine housing (8). The gases push the blades of turbine wheel (9) .

Clean air from the air cleaners is pulled through the compressor housing air inlet (10) by the rotation of the compressor wheel (4). The action of the compressor wheel blades causes a compression of the inlet air. This compression gives the engine more power because the compression allows the engine to burn additional fuel with greater efficiency.

The maximum speed of the turbocharger is controlled by the engine's electronic control of fuel delivery. The maximum speed of the turbocharger is also controlled by the height of the engine above the sea level.

Bearing (5) and bearing (7) in the turbocharger use engine oil under pressure for lubrication. The oil is sent through the oil supply line (3) to the oil inlet port (6). The oil then goes through passages in the center section for lubrication of the bearings. The oil goes out of the oil outlet port (11) at the bottom. The oil then goes back to the flywheel housing through the oil drain line (2).