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Pic. 8: 1. Rear fuel pipe. 2. Front tube of the fuel pipeline. 3. Fuel pump. 4. Hose for supplying fuel to the fuel pump. 5. Carburetor. 6. The axis of the lever of mechanical fuel supply. 7. Discharge valve seat. 8. Discharge valve. 9. Upper pump housing. 10. Filter. 11. Discharge pipe. 12. Pump cover. 13. Suction pipe. 14. Suction valve seat. 15. Suction valve. 16. Diaphragm plate. 17. Internal spacer. 18. Upper diaphragms. 19. External spacer. 20. Lower diaphragm. 21. Stock. 22. Lever for manual fuel pumping. 23. Lever spring. 24. Lower pump housing. 25. Balancer. 26. Fuel tank cap. 27. Pipe of the fuel tank. 28. Hose for communication of the fuel tank with the atmosphere. 29. Receiving tube. 30. Cylinder block. 31. Eccentric roller drive oil pump and ignition distributor. 32. Pusher. 33. Heat-insulating spacer. 34. Adjusting gasket of the insulating spacer. 35. Adjusting lining of the fuel pump. 36. The lever of the mechanical drive of the pump. 37. Cam. 38. Fuel gauge sensor. 39. Fuel tank. I - Scheme of the fuel pump. II - Suction. III - Injection. IV - Scheme of installation of the fuel pump.
The power supply system includes devices for supplying fuel and air to the carburetor, preparing a combustible mixture and exhaust gases. The power system consists of a fuel tank, fuel pump, air filter, carburetor, intake pipe, exhaust manifold, mufflers and pipelines. Fuel is cleaned on a car by fuel filters installed on the receiving tube of the fuel level sensor in the tank, in the fuel pump and carburetor.
Fuel tank 39 steel, welded from two halves. The steel sheets are lead-coated on the inside. Outside the tank is painted with black enamel. The capacity of the fuel tank is 39 liters, including a reserve of 4-6.5 liters.
The tank is installed in the luggage compartment of the body on the right along the course of the car on a rubber gasket and is fixed to the body with two clamps tightened with a bolt. The filler neck of the tank is brought into a niche in the right rear wing and is closed with a blind plug 26 on the thread. To access the plug, you must press the front end of the cover on the wing, which closes the niche.
For ventilation and access to atmospheric air, the fuel tank has a ventilation hose 28, which is brought out by the second end into the niche of the filler neck. Fuel trapped in the vent hose loop while driving on rough roads forms a fluid lock that prevents the gasoline from evaporating from the tank.
On top of the tank, through the gasket, the fuel level sensor 38 is assembled with a branch pipe and a receiving tube equipped with a fuel strainer. Sensor 38 is connected by electrical wires to the fuel gauge mounted on the instrument panel. When there is fuel left in the reserve tank, the float lever closes the contact of the reserve indicator lamp.
The fuel and electrical connections of the tank are covered from above by a shield.
The tank has a drain plug, for access to which there is a hole in the floor of the body, closed with a plug.
Since 1985, drain plugs on fuel tanks have not been installed on cars.
On VAZ-2104 vehicles, fuel tanks from a VAZ-2102 vehicle with a capacity of 45 liters are installed.
Fuel lines 1 and 2 are made of galvanized or lead-coated steel tubes. The fuel lines are interconnected, with the tank, with the fuel pump, as well as the fuel pump 3 with the carburetor 5 with rubber hoses in a fabric braid and secured with clamps with a screw and a nut. The fuel lines are secured to the body with plastic holders. The openings in the body for the passage of fuel lines are sealed with rubber plugs.
Fuel pump 3 diaphragm type, mechanically driven; installed on the left side of the cylinder block, fixed on two studs through a heat-insulating spacer 33 and shims 34 and 35; equipped with a lever 22 manual pumping fuel.
Pump flow not less than 60 l/h at a frequency of 2000 cycles per minute. The pressure developed by the pump is 20-30 kPa.
The fuel pump is driven from the eccentric 31 of the oil pump drive shaft and the ignition distributor through the pusher 32.
The pump consists of a lower housing 24 with drive levers, an upper housing 9 with valves and branch pipes, a diaphragm assembly and a cover 12.
The diaphragm assembly has three diaphragms: two upper 18 working ones for supplying fuel, one lower 20 safety one, which works in contact with crankcase oil and prevents fuel from entering the engine crankcase if the working diaphragms are damaged. Between the working and safety diaphragms, remote outer 19 and inner 17 gaskets are installed. The outer gasket has a hole for fuel to escape to the outside in case of damage to the working diaphragms. Diaphragms with plates and with an internal spacer 17 are mounted on the stem 21 and fixed on top with a nut. The diaphragm assembly is installed between the upper and lower pump casings. A compressed spring is installed on the rod under the diaphragm assembly. The rod 21 is inserted into the slot of the balancer 25 with a T-shaped shank. This design allows, without disassembling the diaphragm assembly, to remove it from the engine.
In the lower housing 24, on the axis 6, a lever 36 of mechanical fuel supply and a balancer 25 are installed. In the lower housing, also on the axle with a cam 37, a lever 22 of manual fuel pumping is installed, which returns to its original position under the action of a spring 23.
In the upper casing 9 of the pump, textolite hexagonal suction 15 and discharge 8 valves are installed. The valves are pressed by springs to brass seats 7 and 14. A cover 12 is attached to the body with a central bolt from above. A plastic strainer 10 is installed between the cover and the body.
When the engine is running, the eccentric 31 of the drive shaft through the pusher 32 acts on the lever 36 and turns the balancer 25, which pulls the pump diaphragms down by the rod 21. At the same time, the diaphragm spring is even more compressed, a vacuum is created, as a result of which fuel fills the working cavity through the suction valve (cavity above diaphragm). When the eccentric runs off the pusher, the lever 36, the balancer 25 and the rod with diaphragms are released. The diaphragms, under the action of a compressed spring, create fuel pressure in the working cavity, the suction valve 15 closes, and fuel is supplied through the discharge valve 8 to the carburetor float chamber.
With a small fuel consumption, the stroke of the diaphragms will be incomplete; in this case, the stroke of the lever 36 will be partially idle.
When manually pumping fuel, the lever 22 is pressed, the cam 37 acts on the balancer 25 and pulls the rod with the diaphragms. Fuel is sucked into the working cavity. When released, the lever and cam return to their original position under the action of spring 23, and the diaphragms pump fuel into the carburetor float chamber.
When installing the fuel pump on the engine, shims 34 and 35 are selected so that the minimum protrusion of the pusher 32 above the mating plane of the heat-insulating spacer 33 (taking into account the gasket 35 between the spacer and the fuel pump) was 0.8-1.3 mm. The minimum protrusion of the pusher is set by slowly turning the crankshaft of the engine. Gaskets are made in three types and have a thickness of 0.30, 0.75 and 1.25 mm. Between the heat-insulating spacer and the cylinder block, a gasket 0.30 mm thick must always be placed.
To determine the malfunction of the fuel pump, disconnect the hose from the discharge pipe 11 of the pump and use the lever 22 for manual fuel pumping to check whether fuel is supplied. In this case, the crankshaft must be in a position in which the stroke of the lever 22 will be full. If fuel is not supplied, then disconnect the hose from the suction pipe 13 of the pump and check whether a vacuum is created at the inlet of this pipe. If vacuum is present, the fuel line or fine fuel filter may be damaged or clogged. If the fuel pump is faulty, there is no vacuum hose, then removal and disassembly of the pump will be required to eliminate the malfunction.
Fuel fine filter. A fine filter can be installed on rubber hoses in front of the fuel pump 3 (not shown in the picture) and secured to the hoses with clamps. Non-separable filter with a paper filter element in a plastic housing, the housing and cover are welded by ultrasonic welding or high frequency currents. The fineness of the filter element is up to 15 microns. For the correct installation of the filter on the hoses, an arrow in the direction of fuel flow through the filter is marked on its body.
Carburetor control drive - lever type. The throttle valve of the primary chamber is opened by pressing the pedal, which is mounted on the lever of the roller, placed in the engine compartment on the brackets of the front panel of the body. One of the roller levers is connected by a longitudinal rod through a two-arm intermediate lever and a transverse rod to the carburetor throttle actuator lever.
The carburetor air damper is controlled by a handle located in the cabin under the instrument panel. The handle is connected by a rod with a three-arm air damper control lever. The thrust shell is attached to the cover of the pneumatic throttle valve of the secondary chamber of the carburetor.
The throttle valve drive of the primary chamber is regulated by changing the length of the longitudinal thrust; at the air damper - by changing the length of the damper drive rod.