- A) interruptions in ignition;
- b) knocking in the cylinder or in several cylinders;
- V) engine overheating;
- G) reduction in effective engine power;
- d) the appearance of excessive black smoke from the exhaust pipe;
- and) increase in fuel consumption;
- h) blue smoke from the exhaust pipe when starting a cold engine.
An inoperative injector can be determined by loosening the high pressure fuel line nuts on each injector in turn. The engine must be running at idle. If, when the fuel line nut on the next injector is loosened, the engine still continues to operate with the same noise or knocks, then this particular injector is faulty.
Checking the injectors for leaks and their repair should be entrusted to a workshop. These works cannot be done on your own, because they require special tools. In addition, there is a risk of injury due to unprofessional performance of the specified work.
Depending on the type of engine and power supply system, nozzles of different types are installed. On XUD9 engines, nozzles of the same shape are installed, regardless of the manufacturer. These nozzles are marked with paint (see illustration 3.0).
3.0 Fuel injector. At points 1 and 2, the corresponding marks are applied with paint. On nozzles manufactured by Bosch, color marking is applied only on the body, at point 1
XUDl I engines can be fitted with different types of injectors.
The body of the injectors installed on 13 cylinders is the same. The injector mounted on the 4th cylinder has a needle stroke sensor designed to determine the start of fuel injection. The signal from this sensor is sent to the electronic control unit for the injection system. Cylinder number 4 and the corresponding nozzle are located on the side of the toothed belt.
Access to the nozzles is difficult and therefore some parts must be dismantled to remove them. The injectors are located next to the glow plugs and protrude from the mount on the cylinder head (see illustration 3.0a)
3.0a Mounting the injector on the engine.
1 - copper ring
2 - heat shield
3 - union nut
4 - nozzle
5 - hexagon nut 27 mm
6 - glow plug
7 - hex nut of the glow plug
1. Disconnect the wire terminal «masses» (-) from the battery.
2. Unscrew the union nut of the high pressure fuel line of the corresponding injector and take the fuel line to the side. You can use an ordinary wrench to loosen the union nuts, but do not allow the wrench to slip on the nut.
3. Disconnect fuel return lines.
4. Unscrew the nozzle using a 27 mm socket wrench. Remove the injector copper O-ring and heat shield gasket (see illustration).
3.4 Unscrew nozzle 1 using a 27 mm socket wrench. Remove the copper sealing ring 2 nozzles and heat shield 3
5. Replace copper O-ring and heat shield. Injector installation sequence is reverse to removal.
6. Install a new O-ring, heat shield and screw in the nozzle (see illustration).
3.6 When installing the nozzle, the heat-shielding gasket must be laid with the convex side up.
1 - nozzle
2 - copper sealing ring
3 - heat shield
4 - glow plug
7. Tighten the nozzle with a torque of 90 Nm. The union nuts of the fuel lines are tightened with a torque of 20 Nm. When tightening the union nuts, do not damage the hexagon of the nut.