3363690 - INTRODUCTION - ENGINE

GLOSSARY

CONDENSATION

Changeover of a substance from a vapour state to a liquid state. Occurs due to compression or cooling.

EVAPORATION

The phenomenon when a body changes from a liquid state to a gaseous state. Occurs at any temperature. The lower the temperature, the slower the change.

RESONANCE

Phenomenon whereby the amplitude of oscillations induced in a vibrating system tend to be enhanced (amplified) beyond all limits under certain conditions.

VISCOSITY

Material property whereby the particles in a body encounter resistance as they slide over one another.The internal resistance or friction valve depends on the nature of the body: high in very small solids, low in viscous fluids and zero in gases.In liquids, viscosity drops rapidly as temperature rises.

HARDENED AND TEMPERED STEEL

Heata treatment applied to special steels to improve their mechanical properties: it involves hardening followed by tempering to make the material much stronger.

HARDNESS TEMPERING

This is achieved when the metal''s structure is harder and stronger at high temperatures than when cold.

TEMPERING

Consists of heating at temperatures < 720°C followed by slow cooling in order to lessen the effects of the tempering without removing them.In this way, the material returns to conditions that are closer to a stable chemical and physical balance.

SENSOR

A system that reacts when subject to any form of energy by changing its state, i.e. one or more of its properties (resistance, volume, temperature etc.).For example, a sensor is a material that undergoes conductivity changes when submerged in a magnetic field.New-generation sensors are solid-state devices produced using microchips that can take readings from their surroundings and produce a response in the form of electrical signals that can be processed so a final action can be taken.Sensors are therefore able to measure force, acceleration, pressure and temperature of gases, liquids and solids etc.

SPECIFICATIONS

TYPE

Current developments

This engine is fitted with a Bosch Motronic electronic ignition system fully managed by an electronic control unit.

Specifications

5 cylinder in-line engine, 20 valves, 2446 cc., petrol, with integrated Bosch ME 3.1 electronic injection-ignition systemPOWER - 125 kW (170 BHP)TORQUE - 221 Nm (22.5 kgm)CYLINDER ARRANGEMENT - 5 in lineBORE -83 mmSTROKE - 90.4 mmCYLINDER CAPACITY -2446 ccCYLINDER HEAD - in heated-treated aluminiumCRANKCASE - in laminar cast ironCRANKSHAFT - in spheroidal cast ironTIMING SYSTEM - two overhead camshafts, 4 valves per cylinder, hydraulic tappetsFUEL SYSTEM - returnless system with Bosch injectionIGNITION - single coils per cylinderEMISSION CONTROL DEVICES - Euro 3 with catalytic converterLUBICATION - forced with gear pumpCOOLING - liquid with forced circulation via centrifugal pump and sealed circuit; radiator and supplementary expansion tank

SYSTEM DETAILS

Devices adopted

To reduce polluting emission levels, these engines are equipped with:

  • exhaust system with catalytic converter and lambda sensors;
  • fuel vapour recirculation.
  • crankcase blowby gas recirculation system.

COMPOSITION

STRUCTURE

The unit is a system made up of the engine and all circuits required for its operation:

  • fuel supply system
  • air supply system
  • exhaust system with catalytic converter and lambda sensors
  • oil vapour recirculation system
  • fuel vapour recovery system.
  • engine cooling system.
The operation of these systems is optimised by an electronic control system governed by a control unit.An awareness of control unit operating strategies allows an overview of the entire system UNIT 10    See descriptions 1056 PETROL INJECTION SYSTEM.