Function of exhaust gas turbocharger: - ra09006020050x(0050)

WARNING: This page does not describe the selected car, but rather 42 other vehicles, including the 1999 Mercedes-Benz S600, 1999 Mercedes-Benz S500, 1999 Mercedes-Benz S420, 1999 Mercedes-Benz S320, and 1999 Mercedes-Benz CL600. However, it is still accessible from the selected car via links, so may be relevant.

Engines 602.96, 603.96, 603.971 TURBO in Models 124, 126, 140, 201 (model 463.3 : for deviations see introductory notes)

SURVEY OF EXHAUST GAS TURBOCHARGERS

Engine

Designation

602.96

Garrett TB 025

1990 or T 025
KKK K14 ⁽²⁾
Garret T 025 ⁽⁴⁾)

603.96

Garrett TB 03 ⁽¹⁾⁽³⁾ or T 03 ⁽¹⁾⁽³⁾
KKK K24 ⁽¹⁾⁽³⁾
KKK 24 ⁽⁵⁾

603.971

Garrett TB 03

⁽¹⁾

Optional

⁽²⁾	Production breakpoint at a later point in time KKK= Kuhnle, Kopp and Kausch.

⁽³⁾	For USA Only California with air recirculation valve.

⁽⁴⁾	With Basic Version Code 62/0 as of 06/91, Austria Only, Finland Only, Switzerland Only, Denmark Only, USA Only Model Year 1992.

⁽⁵⁾	With Basic Version Code 62/0 as of 06/91, Austria Only, Finland Only, Japan Only Model Year 1992.

Engine 602.961, Garrett TB 025

Fig 1: Identifying Exhaust Gas Turbocharger Components (Garrett TB 025)

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Engine 603.96, Garrett TB 03

Fig 2: Identifying Exhaust Gas Turbocharger Components (Garrett TB 03)

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Garrett TB 03 with air recirculation valve

Fig 3: Identifying Exhaust Gas Turbocharger Components (Garrett TB 03 With Air Recirculation Valve)

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

KKK-K24 with air recirculation valve

Fig 4: Identifying Exhaust Gas Turbocharger Components (KKK-K24 With Air Recirculation Valve)

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

General

The exhaust gas turbocharger (ATL) is a turbine machine. The flow energy of the engine exhaust gas is used for driving the turbine, which in turn drives the compressor via a shaft. The ATL is installed between the exhaust manifold and the exhaust pipe. It is connected to the engine oil circuit for lubrication and cooling.

A charge pressure control valve, fitted to the turbine housing or separately, ensures that a charge pressure of 0.95 bar is not exceeded. If the boost pressure control valve is faulty, engine failure is prevented by means of an engine overload protection (pay attention to note).

The exhaust gases of the engine are passed through the exhaust manifold into the turbine housing (h) and impinge on the turbine wheel (i). The flow energy of the exhaust gases starts the turbine wheel (i) rotating. This causes the compressor wheel (d) which is connected via the shaft (n) to the turbine wheel (i) to be driven at the same speed. The maximum rotation speed is approx. 135 000 rpm. The fresh air drawn in by the compressor wheel (d) is precompressed and passed to the engine.

NOTE: Engines 602.962, 603.960/963

Discontinuation of engine overload protection.

PRODUCTION BREAKPOINT AS OF JANUARY 1993

Model	Engine	Engine end no. Manual transmission	Engine end no. Automatic transmission
124.128/188	602.962	027382	-
124.333/393	603.963	-	004004

PRODUCTION BREAKPOINT AS OF FEBRUARY 1993

Model	Engine	Engine end no. Automatic transmission
124.128/188	602.962	017181
124.133/193	603.960	046668

Fig 5: Functional Diagram Turbocharger KKK K24 (Engine 603.96)

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Functional diagram turbocharger KKK K24 (Engine 603.96)

Fig 6: Functional Diagram Turbocharger

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Function diagram

Air Recirculation Valve

(refer also to EDS Operation No. 07.1-010).

In order to create more favorable combustion conditions for the trap oxidizer, the air recirculation valve is continuously opened or closed in accordance with the performance

characteristic map.

After the closing operation, a residual vacuum of approx. 30 mbar is retained at the air circulation valve.

Fig 7: Function Diagram Turbocharger KKK With Air Circulation Valve

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Function diagram turbocharger KKK with air circulation valve California

Model year 1986/87

Charge Pressure Control Valve (KKK)

To prevent the charge pressure rising above a certain level, a charge pressure control valve (a) is attached to the turbine housing (h). The charge pressure is tapped at the compressor housing and passed through the connecting hose (14) to the charge pressure control valve. When the charge pressure is reached, the charge pressure valve begins to open and allows the exhaust gas to flow along the bypass passage (C). Part of the exhaust gas is now flowing directly to the exhaust pipe, with the result that the charge pressure remains at a constant level.

Fig 8: Charge Pressure Control Valve (KKK) Functional Diagram

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Charge pressure diagram - full load

Fig 9: Charge Pressure Diagram - Full Load Graph

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Boost pressure control by means of vacuum-controlled boost pressure control valve Engine 602.96 Model Year 1990

Fig 10: Functional Diagram - Vacuum-Controlled Boost Pressure Control Valve

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Function diagram

Boost pressure control by means of vacuum-controlled boost pressure control valve Engine 602.96 as of Model Year 1991, as of Model Year 1992

Engine 603.971 as of Model Year 1992

Fig 11: Functional Diagram - Vacuum-Controlled Boost Pressure Control Valve

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Function diagram

Function diagram exhaust gas turbocharger

Fig 12: Function Diagram - Exhaust Gas Turbocharger

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Boost pressure control valve vacuum unit

With the boost pressure control, the bypass flap (a) from the turbocharger is opened with the controlled vacuum from the boost pressure control/vacuum control flap vacuum transducer (Y31/5), engine 602.96, or from the boost pressure control vacuum transducer (Y31/4), engine 603.971. The flap is operated by the control linkage (b).

Fig 13: Functional Diagram - Boost Pressure Control Valve Vacuum Unit

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Idling and Lower Part Load

No compression occurs during idling and in the lower part load, the engine is operating as a naturally aspirated engine.

Upper Part Load and Full Load

As the engine load and speed increases, e.g. with an increase in the exhaust gas flow, the turbine wheel (i) is accelerated with the result that the compressor wheel (d) produces a charge pressure up to a certain value. The compressed charge air is passed through the charge air pipe to the individual cylinders. The charge pressure allows increased quantity of fuel to flow through the ALDA unit at the injection pump.

Although charge pressure exists in the deceleration mode, fuel injection is stopped as a result of the control rod position (decel fuel cutoff).