Diesel 5-cylinder engines: the E 250 E 290 D and TD

Diesel 5-cylinder E 250 D (in the domestic market OM 605) from the 2.5-liter technically consistent, despite different numbers of cylinders, a well-known 4-cylinder E 220 D (OM 604). Crank band is mounted on 6 bearings in 5-cylinder engine (similar to the five bearings in 4-cylinder engine). Instead of distributing injection pump (fuel pump, high pressure) mounted in-line injection pump with electronic control. In addition, models with a manual gearbox has a 2-mass flywheel for improved ride.

Another model of the 5-cylinder engine - the E 290 TD (in the domestic market OM 602) with a volume of 2.9 l (fig. 1.11 and 1.12) is the first model of a diesel engine with direct injection passenger car Mercedes-Benz.

Diesel has two valves per combustion chamber. It is directly screwed nozzle. In the conventional system of pre-chamber fuel, so to speak, "stored" in the antechamber before self-igniting directly in the combustion chamber. The direct injection differs from the pre-chamber a significant reduction in fuel consumption. This is achieved through more efficient combustion of the fuel, as it is under high pressure (up to 31 MPa) goes directly into the combustion chamber, which immediately ignited by hot high pressure compressed air.

The engine E 290 TD (OM 602) air is pre-sealed exhaust gas turbocharger (similar to the KKK or Garrett), accelerated and fed into a vortex chamber of the cylinder head.

Additionally, the charge air cooler is used (Fig. 1.13), located in front of the radiator of the cooling system, which brings the temperature of the intake air to 80 ?� C, thereby increasing the density of the air supplied to the combustion chamber.

The compact turbocharger is adjusted in such a way that reaches a maximum of 195 kPa absolute pressure at a frequency of engine speed 1900 ^min -1. In turbo previous models while driving a car or sharp pressing a pedal formed "turboproval" - the lack of incoming air. The engine E 290 TD (OM 602) compressor is adjusted so effectively that this deficiency is almost not felt.

Management of the start of injection is carried out and the number of system EDS (Elektronic Diesel Control), which has about 50 settings. Multiple sensors monitor the state of the engine during the motion change parameters and provides an indication in the form of electrical signals to the EDC, which in turn issues a control command to the number and order of injection.

EDC operates as a running engine and idle speed and the amount of exhaust gas, the outlet to the post-combustion. Management is carried out on the basis of just enough - EDC supplies the combustion chamber as fuel, as necessary for optimum engine performance.

In June 1999, a new inline 5-cylinder diesel engine E 270 CDI model has replaced the E 290 TD. Engine E 270 CDI (Fig. 1.14) was a combination of optimal performance.

Power diesel E 270 CDI has increased by 31.5% compared with the previous model and has reached 125 kW / 170 hp at a frequency of engine speed of 4200 ^min -1, and in the frequency range 1600-2400 ^min -1 torque increased to 370 Nm. Its top speed was 225 km / h and average fuel consumption (NEFZ) - 6,9 liters per 100 km.