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discharge of gasoline from the mains and the formation of air
cocks after shutting down the gas pump.
Structurally, the return valve can be made with a damping
throttle (from Dampfer - Duster, Drossel - diminutive passage
section), built into the fuel pump connector. The damper
smoothes out a sharp increase in the pressure in the supply
system when the fuel pump starts and prevents the pressure
drop when the fuel pump is switched off. The action of the
damper is similar to the operation of the pressure regulator.
At the inlet of foreign gasoline pumps there is a filtering
net. It is intended to detain relatively large foreign particles. If
this grid is damaged, then using a conventional native gasoline
pump will fail in a few months. The electric pump is controlled
by an intermediate relay when the ignition is switched on. If
after 3-5 seconds the starter does not start, the control unit turns
off the gas pump. The next inclusion of the gas pump will occur
when starting the engine starter. A shut-off valve is installed to
prevent the pressure drop in the system at the outlet of the fuel
pump. After the ignition is switched off, the fuel pump stops,
but the system maintains excessive pressure for some time.
The ranges of maximum pressure variations in distributed
petrol injection systems in different cars are 0.25-0.35 MPa.
Pump performance at 20 ° C and 12 V - within 1.5-2.5 l / min.
Operating voltage - 7-15 V, the value of current strength -
within 4.5-9.5 A.
A roller pump with a drive from a DC motor with a
permanent magnet is located next to the fuel tank. The pump
pumps fuel from the tank through the filter into the fuel line or
in the central injection nozzle.
6.4 Individual task. Each student, on the basis of a
positive assessment, receives an individual task for laboratory
work at a poll in the class.

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