Table of contents: Removal ↓ Installation ↓
Faulty injectors can cause severe engine detonation and damage to bearings. If such faults occur, let the engine idle and loosen the union nuts of the injectors one by one. If the detonation disappears when one of the union nuts is loosened, this indicates a faulty injector.
A faulty injector can also be detected by loosening the union nuts in order while the engine is running at fast idle. If the number of revolutions does not change when the union nut is loosened, then the corresponding injector is faulty. The injector can be checked using a pressure gauge (is done in the workshop). Required injection pressure: 120–140 bar.
The first signs of injector failure are:
- cylinder misfires;
- knocking in one or more cylinders;
- engine overheating;
- loss of engine power;
- too black exhaust gas;
- high fuel consumption.
Removal
1. Carefully clean the outside of the high-pressure fuel lines and return fuel lines with cold cleaner or diesel fuel.
2. Remove the high-pressure fuel lines in the kit by loosening the union nuts on the pump and injectors with a slotted spanner. Hold the fastening with a regular spanner. Do not change the bend shape of the pipeline.
Caution: After removing the fuel lines, plug the holes with suitable plugs to prevent dirt and foreign bodies from getting in.
3. Disconnect the fuel return hose.
4. Unscrew the return pipe nuts.
Caution! When doing this, hold the pipeline by the Allen key, otherwise it may bend or break.
5. Remove the return line.
6. Unscrew the injectors with a socket wrench and lay them out in the installation order. If necessary, mark the injectors with tape so that they can be installed in their original places.
7. Cover the nozzle openings to prevent foreign objects from entering.
8. Remove the injector gaskets. The gaskets must be replaced.
Attention! Never clean the injectors or injector needles with wire or a file. Do not mix up the individual injector parts.
Installation
1. Clean the injector holes in the cylinder head and be sure to install four new heat-resistant gaskets. The recess should be facing up. The arrow points toward the cylinder head.
2. Install the injectors and tighten to 70 Nm.
Attention! Overtightening the injectors may result in deformation of the injectors, which in turn will lead to the needle sticking or other malfunctions.
3. Install the return line with four new gaskets and tighten the nuts to 45 Nm.
Caution! When doing this, hold the pipeline from turning with a key.
4. Install the high-pressure fuel lines, tighten the union nuts with a force of 25 N·m. At the same time, hold the fastener from turning.
5. On all injectors, slightly loosen the union nuts of the high-pressure fuel lines.
6. Crank the engine with the starter until fuel emerges from the high-pressure lines.
7. Tighten the union nuts to the specified torque.
8. If necessary, bleed the fuel system with a hand pump.