4.1. General information
The Mazda 626 car is equipped with the line four-cylinder diesel engine of liquid cooling installed cross. The block of cylinders is manufactured of cast iron, a head of the block of cylinders – of aluminum. Valves open the camshaft located from above. The gap of valves is regulated by means of adjusting washers. The gap needs to be checked and if necessary to regulate at procedural service, emergence of knocks in the valvate mechanism or after repair of the engine. On models since 1987 of release the gear belt of the drive of the camshaft puts also fuel pump of high pressure in action.
Principle of operation of the diesel engine
In the diesel engine air is sucked in in cylinders where is exposed to very high extent of compression. At the expense of it temperature in cylinders becomes higher than temperature of ignition of diesel fuel – diesel fuel ignites therefore spark plugs are not required here. On the cold engine of temperature of ignition of fuel only at the expense of high extent of compression it is impossible to reach. In this case the engine is warmed up (preliminary heating of the engine). For this purpose the glow plug in each vortex camera of the diesel engine which is warming up the combustion chamber serves. Fuel is sucked in by the directly fuel pump of high pressure (FPHP) from the fuel tank. The pump creates the necessary high pressure (about 130 bars), and fuel is distributed on cylinders according to the sequence of ignition. At the same time the TNVD regulator doses supply of fuel depending on extent of pressing an accelerator pedal. At a given time diesel fuel is injected through nozzles in a forkamer of the corresponding cylinder. Depending on a form forkamer or the vortex camera the soaked-up air as a result of compression is set in whirl that promotes optimum mixing of air and injectable fuel.
Before hit in the fuel pump of high pressure fuel passes through the fuel filter and is purified of pollution and water. Therefore it is especially important to merge water from the filter or to replace it according to regulations of service.
The fuel pump of high pressure does not demand service. All mobile details of the pump are greased with diesel fuel. The pump is put in action by a gear belt.
As in the diesel engine there is a fuel spontaneous ignition, it cannot be stopped switching off of ignition therefore the engine is equipped with the electromagnetic valve. At switching off of ignition of the valve it is powered off and it locks the channel of supply of fuel. Thanks to it interruption in supply of fuel before blocking of a steering wheel at extraction of a key from the switch (lock) of ignition is guaranteed. At launch of the engine tension moves via the ignition lock on the electromagnetic valve and it opens the channel of supply of fuel.
During the work with the device of injection of the diesel engine observe purity.
Fig. 4.1. An arrangement of basic elements of the diesel engine and elements of the car in a motor compartment: 1 – heater hoses; 2 – diesel engine; 3 – engine support arm; 4 – casing of maple belts; 5 – pump of the hydraulic booster of steering; 6 – accelerator cable; 7 – radiator hose; 8 – engine support arm; 9 – conditioner compressor; 10 – radiator fan wire; 11 – radiator hose; 12 – fan and radiator; 13 – plait of wires of the engine; 14 – elements of system of production of the fulfilled gases; 15 – power shaft; 16 – side casing of the engine; 17 – wheel; 18 – lower cross lever; 19 – tip of steering draft; 20 – stabilizer bar; 21 – air branch pipes; 22 – hose of the brake system; 23 – draft of gear shifting; 24 – draft of the choice of transfers; 25 – the rechargeable battery with a support; 26 – heater hoses; 27 – working cylinder of coupling;
28 – plait of wires of the transmission; 29 – engine support; 30 – air filter; 31 – engine support arm; 32 – rotation frequency sensor; 33 – fuel-supply lines
The arrangement of basic elements of the diesel engine and elements in a motor compartment is shown in fig. 4.1.