fuel injection

Principle of diesel

Feeding circuit

Preheating circuit

Injection pumps

TP 1: Periodic maintenance of the diesel engine

TP 2: Repairing the Diesel Fuel System

TP 3: Disassembly, inspection, repair, assembly and adjustment of an injector

TP 4: Check and repair the cold start circuit

TP 5: Remove and refit the injection pump

TP 6: Controls and settings

Diesel injection system

THE DIESEL INJECTION SYSTEM

- Control on the different elements of a rotary injection pump;

- Disassembly and reassembly of a rotary injection pump

- Questions and problems

- Real or simulated cases or representative vehicles

The diesel engine is a self-igniting engine that sucks in only air and compresses it. This process provides significantly greater compression than the knock-sensitive gasoline engine with a mixture of air and fuel and controlled ignition.

Features of a diesel engine

Advance at admission opening (A.O.A)

Delayed closure of admission (R.F.A)

Advance on ignition (A.A)

Advance at the opening of the exhaust (A.O.E)

Exhaust Closing Delay (R.F.E)

Real Diagram

Advantage of the diesel engine

Disadvantages of the diesel engine

Feeding circuit

Fuel Filter

Feed pump

Injection pump

Speed ​​regulator

Inverter

Discharge pipes

injectors

Different types of power circuits

Supply circuit with pump in line

Circuit in "Aspiration"

Circuit in "low pressure"

Supply circuit with dispensing pump

air filter

Gasoil filter

Filters with priming pump

piping

Feeding pumps

Main types of feed pumps

Diaphragm pump

Piston pump

Single acting pump

Transfer phase

By turning, the camshaft of the injection pump brings the eccentric (1) to the high position. The piston (4) is pushed upwards by the roller (2) and the rod (3). The displacement of the piston causes the shutter (6) to close under the effect of the fuel pressure in the chamber (7), the valve (8) moves away from its seat, the gas oil contained in the chamber (7) s flows towards the chamber (9) it is the transfer phase.

Self-regulating phase

The flow rate of the feed pump being greater than the flow delivered by the injection pump, there comes a time when the pressure in the chamber (9) is equal to the pressure of the spring (5) on the piston (4); it can no longer move, there is no aspiration or repression: it is the self-regulating phase. Recall that the roller (2) is always in contact with the eccentric (1) via a return spring not shown in the diagram.

Left suction. In the center: transfer phase. Right: self-regulating phase.

1.Excentric on the camshaft of the injection pump; 2.Galet; 3. Stem; 4.Piston; 5.Ressort; 6.Admission valve; 7. Room; 8. Discharge valve; 9.Transfer room.

1.Excentric on the camshaft of the injection pump; 2.Galet; 3. 4.Admission valve; 5.Piston; 6.Admission room; 7.Admission valve; 8.Compression chamber; 9.Ressort; 10. Discharge valve; 11.Bedroom; 12. Discharge valve; 13.Transfer room

Injectors

Types of injectors

a) nipple injector and throttling b) injector with holes.

1.Arrival, 2.Support body, 3.Removal nut, 4.Install disc, 5.Injector, 6.Pump-discharge union-nipple, 7.Train-rod, 8.Leak recovery shaft, 9 . Tensioning washers, 10. Discharge channel, 11. Spring, 12. Push rod, 13. Positioning spindle.

Types of injectors.

a) Nipple injector and throttling,

b) Injector with holes.

1.Pressure stud, 2.Injector body,

3.Injector needle, 4.Income finishing,

5.Compression Chamber, 6.Injection Hole,

7. Injection Teat, 8. Pilot Hole,

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