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Skoda FeliciaSince 1994 of releaseRepair and car operation |
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Shkoda Felitsija + Cars of mark Skoda Felicia + The maintenance instruction + Routine maintenance - Engine repair - Repair without extraction from the car of the petrol engine of 1.3 l The description of the basic knots and mechanisms Check of a condition of shatunno-piston group on hearing and measurement компрессионного pressure in cylinders Reduction of the piston of the first cylinder in position of the top dead point (ВМТ) Removal and installation of a cover of a casing of a camshaft Removal, check of a condition and installation of assemblage of an axis коромысел Removal and installation of a head of cylinders in gathering with the inlet pipeline and a final collector Removal, check of a condition and installation of a forward cover, chain and asterisks of drive ГРМ Removal, check of a condition and installation of components of the oil pump Removal and pallet installation картера the engine Replacement of epiploons of a cranked shaft Removal, check of a condition and flywheel installation Check of a condition and replacement of rubber pillows of support of a suspension bracket of the power unit Removal, installation and adjustment of effort of a tension of a belt of a drive of auxiliary units + Repair without extraction from the car of the petrol engine of 1.6 l + Repair without extraction from the car of the diesel engine + Dismantle of the power unit and engine major repairs + Systems of cooling, heating + The power supply system + Engine electric equipment + Coupling + Transmission + Power shafts + Brake system + Suspension bracket and steering + Body and salon furnish + Onboard electric equipment |
The description of the basic knots and mechanisms Head of cylinders (front view)
Head of cylinders (rear view)
Head of cylinders Appearance of a head of cylinders is presented on an illustration. In a head of cylinders combustion chambers are placed. In aluminium moulding of a head запрессованы directing plugs of valves. Plugs are made of pig-iron with 0.5 %-s' addition of phosphorus. In walls of chambers of combustion of a head of cylinders запрессованы saddles of inlet and final valves (the saddle of the inlet valve is more on diameter). Inlet and final channels are deduced on the same party of a head that allows to provide a preliminary warming up of an air-fuel mix in inlet channels. Inlet channels have round section (Ø 25 mm) and are deduced above final, having oval section 22 х 30 mm. From an opposite side of a head of cylinders carving apertures under installation of spark plugs (М14х1.25) are provided. Near to candle niches labels in the form of figures from 1 to 4 are put, covers of the distributor of ignition specifying to what conclusion should be connected ВВ a wire of the given candle. Water galleries are connected to an exhaust outlet near to which the case of the thermostat and with the inlet apertures located in the top part of a head of cylinders, near to combustion chambers is established. The surface of a head interfaced to the block and internal surfaces of chambers of combustion are subjected careful machining with observance of requirements to the form and the cleanliness, allowing to observe similarity of volumes of all chambers of combustion and to achieve equal degree of compression in all cylinders. Besides, processing guarantees tightness of joints. The head of cylinders fastens to the block ten bolts М11 with шестигранными heads and four nuts, наворачиваемыми on hairpins М8. Seven bolts have length of 168 mm, two - 183.5 mm and one - 132.5. In heads of bolts is available шестигранное deepening under прутковый a key on 10 mm. From above the head is closed by a cover which also is cast from an aluminium alloy. The cover of a head of cylinders is equipped маслозаливной by a mouth which is closed by a plastic stopper. Tightness of landing of a stopper is provided at the expense of the equipment with its rubber sealing ring 70х60 mm. Between a head of cylinders and its cover the rubber sealing lining preventing leak of impellent oil is established. The block of cylinders The block of cylinders is the basic bearing detail of a design of the power unit. The block is executed from an easy aluminium alloy by a moulding method under pressure. The weight of the block makes 13 kg. In the bottom part of the block of cylinders three bearings of radical necks of the cranked are located. The cranked shaft has three radical necks (so-called неполноопорный a cranked shaft). Covers of radical bearings are executed from pig-iron and as are not interchangeable, marked designated by corresponding figures. On the second cover from an outer side there is an aperture with a carving for fastening маслозаборника the oil pump. Covers of radical bearings fasten bolts М11, the demanded which effort of a tightening makes 67 ÷ 75 Nanometers). In the block of cylinders channels for a cooling liquid, and also channels for an oil supply are provided. The carving in apertures in the block under bolts of fastening of a head of cylinders begins on 30 mm below the top cut of an aperture thanks to what the best tightness of a joint of knots is provided and concentration of pressure of moulding round fixture decreases. To the bottom part of the block nine bolts М6 the pallet картера fastens. Sleeves of cylinders Sleeves are made of grey pig-iron with addition of 0.5 % of phosphorus. Sleeves are established in apertures of cylinders in the block. The external surface of sleeves is washed by a cooling liquid, i.e. these are so-called "wet" sleeves. Working surfaces of sleeves are exposed хонингованию with a split-hair accuracy cleanliness degree. Each of sleeves is equipped by two adjusting corbels one of which is located from above, and another - on distance about 2/3 lengths of a sleeve is closer to a bottom edge of last. For a guarantee of correctness of installation of sleeves the manufacturer lets out copper ring adjusting washers in the thickness 0.10, 0.12 and 0.14 mm. A selection of adjusting washers achieve, that the sleeve acted from the combustion chamber on strictly set height. Sleeves should act over a block surface on 0.07 ÷ 0.13 mm. Sleeves are made with nominal internal diameter 75.5 mm and packed in groups under admissions of three classes: And, In and With (Specifications see). The sleeve class is put on its lateral surface. The Manufacturer does not provide possibility of use of sleeves of the repair sizes. The gazoraspredelitelnyj mechanism The scheme of action ГРМ The gazoraspredelitelnyj mechanism (ГРМ) operates an admission in cylinders during the corresponding moments of a fresh air-fuel mix and release from chambers of combustion of the fulfilled gases. The engine concerns family of OHV-units, i.e. has the top arrangement of valves. The camshaft, accordingly is below. The scheme of action of the mechanism is presented on an accompanying illustration. Camshaft cams, rotating lift the pushers which movement through bars is transferred коромыслам. Коромысла are put on the separate axis fixed by means of arms on a head of cylinders. Making oscillative motions, коромысла directly influence cores of valves, forcing the last to open and be closed during the necessary moments of time. Each of valves nestles on the saddle two springs (internal and external). Valves move in directing plugs, запрессованных to a head of cylinders. The camshaft operating functioning of valves by means of eight эксцентриковых of cams is executed from a high-quality steel. Cams are tempered by a current of high frequency. The camshaft is established in three bearings of sliding pierced directly in moulding of the block of cylinders. To facilitate shaft installation in the bearings, three of them have all various diameter. The neck first from outside drive ГРМ has the greatest diameter, average - hardly is less, and, at last, last (the nearest to a flywheel), - the least. Camshafts only with necks of the nominal size (Specifications see) are issued. Each pair of cams operates opening and closing of valves of one cylinder. Рассовмещение working ledges (liftings) of cams defines the moments (corners rather ВМТ) opening and closing of valves (Specifications in the beginning of the present Chapter see). On distributive to a shaft, except a conducted asterisk, the gear wheel of a drive of the oil pump and the ignition distributor is established also. In view of told, the vital value gets correctness of mutual position of asterisks as installation of phases depends on it timing. Correctness of position of a camshaft in relation to the cranked is reached by corresponding placing of labels of both asterisks. Labels are executed in the form of superficial drillings and should defend from each other on the distance equal to 12 links of a chain. Thus, the link located over well-aimed conducting asterisk, is considered the first, over a label conducted - the twelfth. Pushers are executed in the form of the open cylinder One party of the bottom of the pusher, co-operating with a cam tore, is flat, with another spherical deepening into which the end face of a bar of a pusher enters is provided. The working surface of a pusher is made very firm. Bars of pushers transfer movement коромыслам a drive of valves. Bars are made ковкой from steel прутка with the tempered and polished ends. The top end of a bar has the bell form whereas the bottom is executed in the form of slightly expanded half-sphere. Bars of pushers of inlet and final valves have identical length. Коромысла serve for transfer of movement from bars of pushers to cores of valves. The surface коромысла, adjoining to a valve core is forged. Коромысла inlet and final valves differ under the form, but are put on the general axis. Turned to a bar of a pusher the shoulder коромысла is equipped by a carving aperture in which the adjusting screw which rotation it is possible to regulate a thermal backlash of the valve is rolled. The head of the adjusting screw is tempered, for blocking the flat counternut is provided. In an average part коромысла are drilled the gauge-switch of the small channel. Through one channel giving of oil for axis greasing коромысел is carried out, чрез oil is injected by the second between coils клапанных springs in a direction of a core of the valve. Valves open and close inlet and final channels of chambers of combustion that allows during the necessary moments of time to make filling of cylinders with a fresh air-fuel mix and to take away from them fulfilled gases. Valves are executed from a special steel. The valve consists of a core and a plate. The konusnaja part of a plate adjoining to a saddle of the valve and carrying the name of the condensing surface, is cut odes by a corner 45 ° 30 ' ± 5 ' (in valves of the Czech manufacture), or 44 ° 50 ' ± 20 ' (in valves of import manufacture). The valve core is executed from a steel, a plate - from alloy АКМВ, and the condensing surface of a plate is in addition covered by a layer of special alloy Stelit F which protects it from destroying influence разогретых to very heats of gases. Inlet valves are executed from the heat-resistant steel, the condensing surface of a plate is formed by a method ковки. Cores of valves are chromeplated that reduces a component of a friction and prevents probability of jamming in directing plugs. Used materials, under condition of observance of periodicity of adjustments клапанных backlashes, guarantee serviceability of functioning of valves during 120 000 km of run. Diameter of a plate of the inlet valve makes 34 mm, final - 30 mm. It is made as much as possible to reduce the area contacting to hot fulfilled gases. On the end of cores of valves flutes under installation of crackers of cutting locks are provided. Cutting locks consist from double конусной plugs - crackers which are fixed on a core by the top plate of springs. Springs press plates of valves condensing surfaces to saddles, providing with that due tightness of chambers of combustion. Springs are made of a special steel. Each valve is equipped by two cylindrical springs: external and internal. Use of two springs instead of one is caused by that owing to limitation of the empty seat, one spring will be not capable to provide due effort of pressing of a plate to a saddle. Springs are twisted in opposite directions thanks to what danger of an interlacing of their coils in case of damage is eliminated. The height of springs is picked up so that at the maximum compression (at the open valve) coils did not adjoin among themselves. The bottom coils of springs rest against a surface of a head of cylinders through a steel washer. Use of such washers has appeared a compulsory measure as the head of cylinders is executed from a soft aluminium alloy. 25Верхними spring end faces rest against a plate fixed on the end of a core of the valve. Nominal parametres клапанных springs are resulted in Specifications. Directing plugs of valves are executed from pig-iron. The problem of plugs consists in constantly to support the valve in correct position concerning a saddle, to provide its free movement and to take away surplus of heat. Plugs запрессованы in a head of cylinders. Release of plugs of the repair sizes is not made. Plugs are put on маслоотражательные caps. From the interior of a cap the ring ledge collecting from a core of the valve surplus of oil is provided. In the top part of a cap the small ring spring providing its constant clip to a core is established. Use маслоотражательных caps allows to lower the expense of impellent oil connected with its penetration into the chambers of combustion. Accordingly, issue level in atmosphere of hydrocarbonic connections decreases. Saddles of valves provide tightness of closing of valves and heat removal from the last. Saddles are executed from special pig-iron, have the form of a ring of rectangular section and under very high pressure запрессованы in a body of a head of cylinders. The material applied to manufacturing of saddles allows to apply to refuelling of the car both Unleaded, and этилированный gasolines. |
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