5.22.3. Features of a design of a power supply system

Fig. 5.18. Scheme of a power supply system of the diesel engine: 1 – engine; 2 – nozzles; 3 – fuel-supply lines of high pressure of the engine; 4 – a hose of removal of gate-type fuel from nozzles to TNVD; 5 – TNVD; 6 – a fuel supply hose from the filter of thin purification of fuel to TNVD; 7 – a hose of discharge of fuel from TNVD to the union of the filter of thin purification of fuel; 8 – filter of thin purification of fuel; 9 – a fuel intake fuel-supply line from tanks; 10 – fuel electric pump; 11 – filter of rough purification of fuel; 12 – right fuel tank; 13 – left fuel tank; 14 – valve of the fuel tank; 15 – jet pump; 16 – a fuel-supply line of discharge of fuel in tanks; 17 – perepuskny valve

The scheme of a fuel supply system is shown in fig. 5.18.
To the filter 8 of thin cleaning fuel moves under pressure the fuel electric pump 10 of the right fuel tank 12 via the filter 11 of rough purification of fuel. If pressure of the fuel given by the electric pump is more than 60-80 kPa (0,6–0,8 kgfs/cm2), the valve 17 opens perepuskny, taking away excess fuel in a fuel-supply line of discharge 16.
The fuel purified by the filter of thin cleaning comes further to the fuel pump 5 of the high pressure (TNVD). From TNVD fuel by means of TNVD plunger distributor on fuel-supply lines 3 high pressures move to nozzles 2 according to an operating procedure of cylinders.
Nozzles inject fuel into the engine combustion chamber.
Excess fuel and the air which got to system are taken away from nozzles, TNVD and the perepuskny valve on fuel-supply lines of discharge of fuel in tanks.
With the diesel engine install the fuel pump 5 of high pressure like VE of Bosch with the built-in toplivopodkachivayushchy pump, the proofreader on pressurization on the UAZ Hunter cars and the electromagnetic valve of a stop of fuel feeding. On the UAZ Hunter cars TNVD with the dual-mode mechanical regulator of frequency of rotation of a bent shaft is applied.
The TNVD main function is the dosed supply of fuel in engine cylinders under high pressure, in strictly certain timepoint.

It is forbidden to run completely out of fuel from a power supply system as lubricant of the rubbing details of TNVD is carried out by fuel, and at full fuel use of TNVD will fail.
TNVD is a high-precision product therefore its repairs are recommended to be made only in the workshops which are specially equipped for these works and service stations of cars.

Fuel nozzles 2 (see fig. 5.18) the closed type, with two-phasic supply of fuel, fuel pressure at the first stage makes 19,7 MPas (197 kgfs/cm2), and on the second – 30,9 MPas (30,9 kgfs/cm2).
The filter of thin purification of fuel 8 (see fig. 5.18) detains small particles in fuel (about 3-5 microns) to ensure normal functioning of TNVD and nozzles as these elements of system are high-precision details.
The valve 17 (see fig. 5.18) is installed by Perepuskna on the filter of thin purification of fuel and intended for discharge of the excess fuel given by the fuel pump, back to the fuel tanks. With a pressure of fuel of 60-80 kPa (0,6–0,8 kgfs/cm2) perepuskny the valve opens, redistributing a part of fuel from the fuel supply union in the union of the drain highway.