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Pic. 10. Engine lubrication system: 1. Branch pipe for removal of crankcase gases into the air filter housing; 2. Oil filler cap; 3. Pipe suction of crankcase gases into the throttle space of the carburetor; 4. Exhaust hose connection; 5. Oil supply channel to the camshaft bearings; 6. Oil line in the cylinder head; 7. Camshaft; 8. Oil pressure indicator sensor; 9. Pump pressure reducing valve; 10. Oil supply channel from the pump to the filter; 11. Front crankshaft oil seal; 12. Oil supply channel from the oil receiver to the pump; 13. Oil pump drive gear; 14. Crescent protrusion between the gears; 15. Oil pump driven gear; 16. Channel for supplying oil from the filter to the main oil line; 17. Anti-drainage valve; 18. Oil receiver; 19. Cardboard filter element; 20. Drain plug; 21. Oil sump; 22. Bypass valve; 23. Oil supply channel from the main bearing to the connecting rod; 24. Oil supply channel to the main bearing of the crankshaft; 25. Main oil line; 26. Channel for supplying oil to the oil line of the head of the block; 27. Air filter; 28. Carburetor; 29. Hose for removal of crankcase gases to the air filter housing; 30. Hose for removal of crankcase gases into the throttle space of the carburetor; 31. Oil separator mesh; 32. Exhaust hose crankcase gases; 33. Oil level indicator; I. The scheme of the oil pump; II. Engine crankcase ventilation diagram.
The engine lubrication system is combined, in which part of the parts is lubricated under pressure, part by gravity and splashing. The capacity of the lubrication system is 3.5 liters.
Under pressure, the main and connecting rod bearings of the crankshaft, camshaft bearings are lubricated.
Oil flowing from the gaps and sprayed by moving parts lubricates the cylinder walls, pistons with piston rings, piston pins in piston bosses, camshaft cams, valve lifters, and valve stems in their guide bushings.
The lubrication system includes an oil crankcase 21, an oil pump with a pressure reducing valve 9 and an oil receiver 18, an oil channel system, a full-flow oil filter with a filter element 19, a bypass valve 22 and an anti-drain valve 17, an oil level indicator 33 and an oil filler neck.
The oil pressure is controlled by sensor 8, which is screwed into the oil line hole in the cylinder head, which is connected to the main oil line in the cylinder block. The pressure should be 4.5 kgf / cm2 at a crankshaft speed of 5600 rpm. The minimum oil pressure must be at least 0.8 kgf/cm2 at 750-800 rpm. When the oil pressure drops below the allowable limit, the oil pressure control lamp and the light board light up in red "STOP" in the instrument cluster. The circulation of oil during engine operation is as follows. The oil pump, located at the front end of the crankshaft, sucks oil through the filter mesh of the oil receiver 18, the suction tube and channel 12 into the pump housing and delivers it through the channels 10 in the cylinder block to the full-flow filter. In the filter, the oil is purified from mechanical impurities and resinous substances. The filtered oil through channel 16 enters the main oil line 25, which runs along the cylinder block, and from there it is supplied through channels 24 in the partitions of the cylinder block to the crankshaft main bearings. The main bearing shells have two holes through which oil penetrates into the annular grooves on the inner surface of the shells. From these grooves, part of the oil goes to lubricate the main bearings, and the other part through the channels drilled in the necks and cheeks of the crankshaft to the bearings of the lower heads of the connecting rods. From the side hole of the connecting rod bearing, a jet of oil enters the cylinder mirror at the moment the bearing hole coincides with the channel in the connecting rod journal.
The oil removed from the cylinder walls by the oil scraper ring is discharged through the holes in the piston into the piston and lubricates the piston pin bearings in the piston bosses.
In the connecting rod journals of the crankshaft, centrifugal cleaning of oil from foreign impurities contained in the oil occurs, which accumulate in inclined channels under the action of centrifugal forces in the space from the holes in the connecting rod journal to the plug of the crankshaft oil channel.
From the main oil line 25, oil is supplied through vertical channels 26 in the block and cylinder head to the oil line 6 of the cylinder head, and from there through channels 5 to the camshaft bearings. The oil flowing from the camshaft bearings lubricates the working surfaces of the cams and valve lifters.
The engine oil pump is assembled in a special housing attached to the front wall of the cylinder block. The oil pump is single-section, gear, with internal gears. The drive gear 13 of the oil pump is mounted on the front end of the crankshaft.
The driven gear 15 is located in the oil pump housing. To ensure the necessary clearances between the gears and the housing when the temperature changes, the housing is cast from cast iron, the gears are made from cermet. In the housing, the suction cavity is separated from the discharge cavity by a sickle-shaped protrusion 14.
A pair of pump gears rotates in the housing with a clearance of 0.03-0.08 mm in height and 0.10-0.176 mm in the diameter of the driven gear. The maximum allowable gaps in the interface are 0.12-0.15 mm in height and 0.30 mm in diameter.
When the engine is running (see oil pump diagram) the driving 13 and driven 15 gears of the pump suck in oil and pump it into the discharge cavity of the pump with the cavities of the teeth. At pressures above 4.5 kgf/cm2 the pressure reducing valve 9 opens, and part of the oil is bypassed from the pressure cavity into the suction cavity of the pump.
The oil filter is screwed onto the fitting and pressed against the annular shoulder on the block. The tightness of the connection is ensured by a rubber gasket installed between the filter cover and the shoulder of the block. The oil enters the filter through channel 10 and, having passed the paper filter element 19, exits into the main line of the block through the central hole, the attachment fitting and channel 16.
the filter has an anti-drainage valve 17, which prevents oil from draining from the system when the engine is stopped, and a bypass valve 22, which is activated when the filter element is clogged and bypasses oil in addition to the filter into the oil line.
Engine ventilation system
Forced crankcase ventilation removes gases, gasoline vapors from the crankcase, sucking them into the intake tract and engine cylinders, which increases the service life of the oil and increases the durability of the engine. In addition, crankcase ventilation prevents pressure build-up in the crankcase due to the ingress of exhaust gases into it. And since the ventilation system is closed, crankcase gases are prevented from entering the car interior, and the emission of toxic substances into the atmosphere is reduced.
Ventilation is carried out by suction of crankcase gases through the exhaust hose 32, through the grid 31 of the oil separator, the hose 29 into the air filter housing, and also through the hose 30 into the throttle space of the carburetor.