2.1. General description of new engines of the L8, LF and L3 models
Fig. 2.1. Chart of dynamic characteristics of engines of the Mazda 3 car
On the Mazda 3 car modern engines of new generation with improved dynamic and maintainable harakteristikm are installed. The L8 engine – with a working volume of 1,8 l, max. power – 88 kW (120 h.p.), max. is abrupt. the moment – 165 N · m / 4300 min.-1 gathering the maximum speed of 197 km/h. The LF engine – with a working volume of 1,8 l, max. power – 104 kW (141 h.p.), max. is abrupt. the moment – 181 N · the m / 4100 min.-1 gathering the maximum speed of 208 km/h. The L3 engine – with a working volume of 2,3 l, max. power – 122 kW (166 h.p.), max. is abrupt. the moment – 207 N · the m / 4000 min.-1 gathering the maximum speed of 214 km/h. The L3 engine can be supplied with a turbocompressor – the Sequential Valve Timing (S-VT) system. The principle of action of a turbocompressor is that the drive of a turbocompressor works thanks to energy of the burned-down fulfilled gases. The compressor consists of two axial bladed wheels. The hot fulfilled gases get to the turbocompressor case where untwist a driving (first) wheel to the frequency of rotation of 100 000 min.-1. The driving wheel, in turn, untwists by means of a shaft the second bladed wheel which pumps air in the compressor and gives it to the combustion chamber. The warmed air which passed through a turbocompressor is cooled in a radiator of the soaked-up air. Cooling also provides a bigger gain of the power (fig. 2.1).
Fig. 2.2. General view of engines of the Mazda 3 car
The Mazda company brought a number of technical improvements in a design and technical components of new engines.
For example, on engines of the L3 model the mechanism of change of phases of gas distribution is used. For reduction of lump of the car the block of cylinders on new engines is manufactured, as well as a head of the block of cylinders, from aluminum alloy.
Big changes are made to a constructive and mechanical part of engines for the purpose of reduction of vibrations and noise level. So, for example, on engines of the L3 model the balancing block of cassette type is used. On all engines the silent chain of the drive of the mechanism of gas distribution is established now. The block of cylinders is supplied with a long skirt of the piston and the integrated cover of radical bearings. Besides, on all engines the pulley of a bent shaft with a damper of tortional fluctuations and a suspension bracket of pendular type is applied.
It is simplified, for maintainability improvement, a contour of a belt of the drive of auxiliary units. Now one driving belt is applied to all auxiliary units of the engine. The tension of a driving belt is regulated by an automatic natyazhitel. The cover of a forward part of the engine has an opening for carrying out maintenance (for an unblocking of a ratchet of adjustment of a chain and fixing of the lever of a natyazhitel).
As the power plant in the Mazda 3 cars 4-cylinder engines in which cylinders are located in one row are used. From below the engine is closed by the pallet forming a case which at the same time is the tank for the oil necessary for lubricant, cooling and protection of details of the engine from wear.
All three engines 16-valvate, having on four valves on one cylinder. Valves are put in action by two camshafts located above through dish-shaped pushers.
Lubricant of the engine is provided by the oil pump installed on the face side of a case and put in action from a bent shaft. The oil which is soaked up from the oil pallet moves through openings and channels to bearings of cranked and distributive shaft and to the working surfaces of cylinders.
Preparation and supply of fuel-air mix are carried out by the electronic control system of the engine which is not demanding service.