printable version

Fuel-injection systems

The fuel injection system K-Jetronic

On engines of cars of the models "230" and "280" establishes a mechanical fuel injection system ?�K-Jetronic?� company Bosch.

The operating principle of a fuel injection system

The fuel pump draws fuel from the tank and delivers it to the accumulator, where the fuel pressure is maintained in the system within 4.5-5.2 kg / ^cm2. Fuel is supplied through a filter under pressure to the fuel distributor-dispenser.

Fixed to the movable arm drive pressure air flow meter, which is installed between the air cleaner and the throttle valve is deflected depending on the dilution air into the engine. Offset pressure disk meter of air is transferred to the distributor plunger dispenser-distributor of fuel, thereby determining the amount of fuel delivered. Distributor fuel depending on the position of the pressure drive air mass meter continuously delivers the engine cylinders through fuel injectors required, ensuring the optimum fuel-air mixture. The dispenser-distributor of fuel and air flow meter regulator to form a mixture.

The regulator control pressure reduces the pressure distribution on the piston during the engine warm-up. Reduced control pressure at the same flow rate of air increases the fuel supply and, consequently, to the enrichment of the fuel mixture.

Additional air valve installed in the air duct, performed in parallel throttle, the engine brings an additional amount of air at the starting and warming up the engine, which leads to an increase in the speed of the crankshaft of the engine idling.

To facilitate the cold start injector is provided an electromagnetic launcher, the duration of the opening of which is adjusted depending on the temperature of the coolant heat timer.

Data for adjustment

Characteristic	Value
The fuel pressure in the system, kg / cm 2	4.5-5.2
Control pressure in a warm engine, kg / cm 2	2.7-3.1
Control pressure at the warm engine idling, kg / cm 2	3.4-3.8
The control pressure in a cold engine depending on the coolant temperature (see. The injection system), kg / cm 2	0.5-2.0
The residual fuel pressure in the system, however, kg / cm 2	1.7
Engine speed at idle, rev / min	900 ?� 50
The content of carbon monoxide (CO) in the exhaust gas,%
"230"	eleven
"280"	<3.0

Fuel pump

Electric multiple-fuel pump.

Characteristic	Value
Brand and catalog number	Bosch 0580254982
Fuel feed pressure, kg / cm 2	5.5
Pump capacity, l / h	100
Pump performance when checking a car filled with 1/2 of the fuel tank 30 cm 3	750
Operating voltage, V	7-15
Consumption current, not more than, A	4.7

Fuel filter

Characteristic	Value
Brand	Purolator
Type:
"280" until August 1987	GF 140/1
from September 1987	GF 140/1
"230"	GF 148
Mark and catalog ?�� Bosch	0438060043

Fuel Drive

Characteristic	Value
Mark and catalog ?�� (?�230?�)	Bosch 0580254982
The volume of the chamber in cm 3 ("280")	20
Residual Pressure, kg / cm 2
"230"	1.7-2.4
"280"	50

Regulator mixture

Characteristic	Value
Brand and catalog number
"230"	Bosch 0438040088 and 0438060025
"280"	Bosch 0438040009 and 0438060043

Airflow Meter

Characteristic	Value
Brand and catalog number	Bosch 0438120158 and 0438120086
Colour Index	yellow and purple

The dispenser-fuel distributor

Characteristic	Value
Brand and catalog number	Bosch 0438100108

Injectors

Characteristic	Value
Brand and catalog number
"230"	Bosch 0437502006
"280"	Bosch 0437502007 EP / LKE 7
The beginning of injection pressure, kg / cm 2	2,7-3,8
The cone angle of fuel spray ("280")	35 ?�

Electromagnetic launcher nozzle

Characteristic	Value
Brand and catalog number
"230"	Bosch 0280170410
"280"	Bosch 0280170405 and 0280170411
Rated voltage,	12
Operating pressure kg / cm 2
"230"	4.5
"280"	-4.5
Operating voltage, V	7-15
Power consumption	37
The cone angle of fuel spraying ("280")	80 ?�
Injection volume, cm3 / min	95-135

Thermal time switch

Characteristic	Value
Brand and catalog number	Bosch 0280130214 and 0280130220
Rated voltage,	12
The temperature of the contact opening, ?� C	35
Duty cycle not more than, with	8

Relay cold start

Characteristic	Value
Brand and catalog number	Bosch 0332003028

The regulator control pressure

Characteristic	Value
Brand and catalog number	Bosch 0438140005
Rated voltage,	12
The maximum permissible voltage (short-term), B	20
Operating voltage, V	7-15

Additional air valve

Characteristic	Value
Brand and catalog number
"230"	Bosch 0280140134
"280"	Bosch 0280140100
The minimum voltage,	12
The maximum permissible voltage (short-term), B	20
Operating voltage, V	7-15

The fuel injection system L-Jetronic

On engines of cars, "280E" applied intermittent fuel injection system with electronic control of the company L-Jetronic Bosch.

The operating principle of a fuel injection system

The electric fuel pump draws fuel from the tank and delivers it under pressure of about 2.5 kg / ^cm 2 through a fine filter to the fuel rail, hose connection with each cylinder of the engine. Mounted from the end of the fuel rail, the fuel pressure regulator maintains a constant injection pressure and performs draining excess fuel to the tank, i.e. it circulates in the fuel system, and it eliminates the formation of fuel vapors.

The amount of fuel injected is determined by the electronic control unit depending on the amount and temperature of the intake air of the engine speed and the engine load and the coolant temperature. The main parameter that determines the dosage of fuel is the amount of intake air measured by the air flow meter. Incoming air flow deflects the pressure drive, overcoming the force of the spring, and moves it at a certain angle, which is converted into a voltage by means of a potentiometer. The corresponding electrical signal is transmitted to the control unit, which determines the required amount of fuel at the moment of the engine and outputs to the solenoid valves injector pulses time the fuel supply. Regardless of the position of the nozzle inlet valves simultaneously inject fuel twice for each revolution of the camshaft. If the inlet valve is closed, fuel collects in the space upstream of the valve and is sucked into the next cylinder during its opening simultaneously with air.

Additional air valve installed in the air duct, performed in parallel throttle, the engine brings an additional amount of air at the cold start and warm up the engine, which leads to an increase in the speed of the crankshaft of the engine idling.

To facilitate the cold start injector is provided an electromagnetic launcher, the duration of opening of which varies depending on the coolant temperature times the thermal relay.

The fuel injection system L-Jetronic consists of the following elements:

• pressure regulator Bosch, catalog ?��?�� 0280160014, 0280160213;
• ECU Bosch, catalog ?��?�� 0280001108, 0280001300;
• coolant temperature sensor Bosch, catalog number 0280130023;
• thermal time relay Bosch, catalog ?��?�� 0280130219, 0280130214;
• Airflow Meter Bosch, catalog ?��?�� 0280203002, 0280202015 (the normal flow of air at a pressure of 980 mbar and a temperature of 20 ?� C, ³ mm / h: 550);
• temperature sensor;
• Switch the throttle Bosch, catalog ?��?�� 0280120206, 0280120302 (permissible opening angle of contact of idling: 90 ?�; the opening angle of contact at full load: 60 ?�);
• two additional resistors;
• electromagnetic injectors Bosch, catalog ?��?�� 0280150152, 0280150203 (the beginning of the injection pressure, kg / ^cm 2: 2.0-3.0);
• electromagnetic launcher injector Bosch, catalog number 0280170032 (working pressure, kg / ^cm 2: 2.0-3.0);
• sensor oxygen concentration in the exhaust gas;
• electric fuel pump Bosch, catalog number 0580464013;
• relay.

Data for adjustment

Characteristic	Value
The engine speed of the engine at idle, rev / min	900 ?� 50
The content of carbon monoxide (CO) in the exhaust gas, not more,%	0.5-2.0

Tightening torques of the main threaded connections kgs.m