5.1. Features of a design
Fig. 5.1. Engine 1,5 L (SOHC)
Install cross located four-cylinder four-cycle petrol engine of fashion on the Chevrolet/Daewoo Lanos cars. 1,5 L (SOHC) with a working volume of 1,5 l, with a line vertical arrangement of cylinders and liquid cooling. The general design of the engine is shown in fig. 5.1, and separate details and knots — in fig. 5.2.
Fig. 5.2. Details and knots of the engine 1,5 L (SOHC): 1, 2, 4, 9, 25, 29, 32, 57, 70, 73, 77, 84, 86, 95, 96, 98, 103, 106, 122 – bolts; 3 – lower cover of the drive of the gas-distributing mechanism; 5, 30, 58, 75, 85, 94 – washers; 6 – forward cover of the drive of the gas-distributing mechanism; 7 – belt of the drive of the gas-distributing mechanism; 8 – cogged pulley of the camshaft; 10 – back cover of the drive of the gas-distributing mechanism; 11, 81 – splines; 12 – camshaft; 13 – camshaft epiploon; 14 – valve of system of ventilation of a case of the engine; 15 – laying of a cover of a head of the block of cylinders; 16 – laying of the valve of recirculation of the fulfilled gases; 17 – laying of an inlet pipe; 18, 59 – nuts; 19 – throttle knot; 20 – laying of throttle knot; 21 – inlet pipe; 22 – a vacuum hose of system of recirculation of the fulfilled gases; 23 – the valve of system of recirculation of the fulfilled gases; 24 – transport eye; 26 – cover of a head of the block of cylinders; 27 – stopper of an oil-filling mouth; 28 – laying of a stopper of an oil-filling mouth; 31 – persistent flange of the camshaft; 33 – head of the block of cylinders; 34 – press valve drive lever; 35 – hydrocompensators of gaps in the drive of valves; 36 – the directing crackers of press levers of the drive of valves; 37 – locking crackers of springs of valves; 38 – top plates of springs of valves; 39 – springs of valves; 40 – oil scraper caps; 41 – mechanism of a provorachivaniye of the final valve; 42 – the directing plugs of valves; 43 – final valve; 44 – inlet valve; 45 – lower plate of a spring of the inlet valve; 46 – perepuskny lubrication system valve; 47 – cap; 48 – sensor of temperature of cooling liquid of a control system of the engine; 49 – hairpin of fastening of a final collector; 50 – laying of a final collector; 51 – final collector; 52 – top compression ring; 53 – lower compression ring; 54 – top disk of an oil scraper ring; 55 – dilator of an oil scraper ring; 56 – lower disk of an oil scraper ring; 60 – thermoscreen of a final collector; 61 – index (probe) of level of oil; 62 – the directing tube of the index of level of oil; 63, 64, 83 – adjusting plugs; 65 – cap of a water shirt of the block of cylinders; 66 – union of an oil filter; 67 – oil filter; 68 – plug; 69 – plug stopper; 71 – flywheel; 72 – back epiploon of a bent shaft; 74 – an opening stopper for oil discharge; 75 – a sealing ring of a stopper of an opening for oil discharge; 76 – oil case; 78 – covers of radical bearings of a bent shaft; 79 – lower inserts of radical bearings of a bent shaft; 80 – bent shaft; 82 – top inserts of radical bearings of a bent shaft; 87 – oil receiver; 88 – stopper of the reducing valve; 89 – sealing ring of a stopper of the reducing valve; 90 – spring of the reducing valve; 91 – plunger of the reducing valve; 92 – safety valve; 93 – pulley of the drive of auxiliary units; 97 – tension roller of a belt of the drive of the gas-distributing mechanism; 99 – cogged pulley of a bent shaft; 100 – forward epiploon of a bent shaft; 101 – the sensor of an alarm lamp of emergency pressure drop of oil (if it is established); 102 – sealing ring of the sensor of an alarm lamp of emergency pressure drop of oil; 104 – oil pump; 105 – stopper cap; 107 – branch pipe of system of ventilation of a case; 108 – water pump; 109 – sealing ring of the water pump; 110 – laying of the oil pump; 111 – cooling system branch pipe; 112 – block of cylinders; 113 – rod cover; 114 – lower insert of the conrod bearing of a bent shaft; 115 – top insert of the conrod bearing of a bent shaft; 116 – rod; 117 – piston finger; 118 – piston; 119 – laying of a head of the block of cylinders; 120 – head of the block of cylinders; 121 – thermostat cover; 123 – sealing ring of the thermostat; 124 – thermostat
The 63 kW engine (86 h.p.) with the top arrangement of one five-basic camshaft has two valves on each cylinder. The camshaft is given to rotation by the reinforced gear belt, gaps in the drive of valves are eliminated with the hydrocompensators connected by channels to the lubrication system.
The head of the block of cylinders is made of aluminum alloy according to the cross scheme of a purge of cylinders (inlet and final channels are located on the opposite sides of a head). In a head of the block saddles and the directing plugs of valves are pressed. Inlet and final valves have on one spring recorded through a plate by two crackers. Valves are set in motion by the camshaft via the levers leaning one shoulder on the hydrocompensators screwed in a head of the block of cylinders, and to others — on the guides established on the top end faces of valves.
The block of cylinders represents the uniform casting forming cylinders, a cooling shirt, the top part of a case and five support of a bent shaft executed in the form of case partitions. The block is manufactured of special high-strength cast iron with the cylinders chiseled directly in a block body. The covers of radical bearings processed assembled with the block are not interchanged. On the block of cylinders special inflows, flanges and openings for fastening of details, knots and units, and also channels of the trunk oil main are executed.
The bent shaft forged from special steel rotates in the radical bearings having thin-walled steel inserts with an antifrictional layer from aluminum-tin alloy. Axial movement of a bent shaft is limited to the special flanges executed on an average radical neck and leaning on fillets of the inserts of the average radical bearing increased on thickness.
Pistons are manufactured of aluminum alloy. For reduction of pressure of the piston by a cylinder wall during the working course the axis of openings under a piston finger is displaced on 0,7 mm from an axis of symmetry of the piston to the right side. On a cylindrical surface of a head of the piston ring flutes for two compression and one oil scraper rings are executed, and the last consists of three sections.
Piston fingers are established in lugs of pistons with a gap and pressed with a tightness in the top heads of rods. Rods are connected by the lower heads to conrod necks of a bent shaft through thin-walled inserts which design is similar to radical.
Rods steel, shod, with a double-T section core.
The system of ventilation of a case of the closed type is not reported directly with the atmosphere therefore along with a suction of gases and vapors of gasoline in a case depression at all power setting is formed that increases reliability of various consolidations of the engine and reduces emission of toxic substances in the atmosphere. Ventilation are a part of the system the valve installed in a cover of a head of the block of cylinders, the hose of a big branch of system connecting a cavity under a block head cover to the airbringing sleeve and the hose of a small branch connecting system of ventilation to an inlet pipe.
Under the influence of depression in an inlet pipe crankcase gases on the channel in the block of cylinders of the engine and to a ventilating hose are sucked in in a cavity under a cover of a head of the block of cylinders from where via the valve and a hose of a big branch come to the airbringing sleeve where mix up with the air given to the engine, and then through throttle knot — in an inlet pipe of the engine. The formed gas mix together with fuel comes to cylinders of the engine and there burns down.
In certain cases, for example at strong wear of tsilindroporshnevy group or long operation of the engine with high loading, the capacity of system of ventilation is insufficient. In this case a part of crankcase gases is taken away on a small branch in an inlet pipe from where moves in engine cylinders for burning. Besides the small branch works also at the idling mode at completely closed butterfly valve.
Basic element of system is the valve. At completely open butterfly valve when depression in an inlet pipe is small, the valve is completely open under the influence of the spring which is built in it and crankcase gases freely pass in the airbringing sleeve. At the closed butterfly valve (the idling mode) depression in an inlet pipe increases, the section of the valve through passage decreases, intake of crankcase gases in a sleeve steady functioning of the engine in the idling mode is limited and ensured.
The cooling system of engines tight, with a broad tank, consists of the shirt of cooling executed in casting and surrounding cylinders in the block, combustion chambers and gas channels in a head of the block of cylinders. Compulsory circulation of cooling liquid is provided by the centrifugal water pump with the drive from a bent shaft a gear belt of the drive of the gas-distributing mechanism. For maintenance of normal working temperature of cooling liquid the thermostat blocking a big circle of system at not heated-up engine and low temperature of cooling liquid is installed in the cooling system.
The power supply system consists of the fuel tank, the electric fuel pump installed in the fuel tank, throttle knot, the filter of thin purification of fuel, the regulator of pressure of fuel, nozzles and fuel-supply lines and also includes the air filter.
The system of ignition microprocessor, consists of the coil of ignition, high-voltage wires and spark plugs. The electronic block of a control system of the engine operates the coil of ignition. The system of ignition at operation does not demand service and adjustment.
The power unit (the engine with the transmission, coupling and the main transfer) is installed on three support with elastic rubber elements: two lobbies (left and right) perceiving the bulk of the power unit, and back, compensating torque from transmission and the loadings arising at start-off of the car from the place, dispersal and braking.
At the known skill and attentiveness many malfunctions of the engine and its systems can be determined by color of the smoke which is coming out an exhaust pipe quite precisely. Blue smoke demonstrates hit of oil in combustion chambers, and constant smoking — a sign of strong wear of details of tsilindroporshnevy group. Emergence of smoke at throttlings, after long scrolling by a starter, long work idling or right after braking by the engine indicates, as a rule, wear of oil scraper caps of valves. Black smoke — too rich mix because of malfunction of a control system of the engine or nozzles. Gray or dense white smoke with moisture impurity (especially after an engine overheat) means that cooling liquid got to the combustion chamber through the damaged laying of a head of the block of cylinders. At strong damage of this laying liquid sometimes gets also to an oil case, oil level sharply increases, and oil turns into a muddy whitish emulsion. White smoke (steam) at not heated-up engine in damp or in cold weather — the normal phenomenon.
It is quite often possible to see the car standing in the middle of a city stopper with an open cowl which is letting out puffs of vapor. Overheat. Better, of course, not to allow it, glancing at the index of temperature more often. But nobody is insured from the fact that the thermostat can unexpectedly fail, the electric fan or will just begin to flow cooling liquid. If you missed the overheat moment, do not panic and do not aggravate a situation. The overheat as its possible consequences is not so terrible. Never at once you suppress the engine — it will receive heatstroke and, perhaps, остыв, in general will refuse to be started. Having stopped, let's it work on single turns, at the same time in system liquid circulation will remain. Include a heater on the maximum power and open a cowl. If there is an opportunity, water a radiator with cold water. Only having achieved decrease in temperature, stop the engine. But never at once open a stopper of a broad tank: on the superheated engine the geyser from under an open stopper is provided. You do not hurry, let's everything cool down, and you keep health of the car and your own health.
Practically all instructions to the car contain the recommendation at launch of the engine surely to squeeze out coupling. This recommendation is justified only in case of start-up in a hard frost not to spend energy of the rechargeable battery for a provorachivaniye of shaft and gear wheels of the transmission in the thickened oil. In other cases it is just the recommendation in order that the car did not start if on forgetfulness transfer is included. This reception is harmful to the engine as at the squeezed-out coupling the considerable effort is transmitted through it on the persistent bearing of a bent shaft, and at start-up (especially cold) lubricant to it long does not arrive. The bearing quickly wears out, the bent shaft receives an axial side play, and start-off from the place begins to be followed by strong vibration. Not to damage the engine, take in a habit to check position of the lever of gear shifting before start-up and to launch the engine at the tightened emergency brake, without squeezing out coupling without emergency.