- a) Install the injector on the test stand.
- b) Pump the fuel injection lever quickly several times to create pressure to clear the nozzle opening.
- c) Slowly pump the lever and use the pressure gauge to determine the pressure at which the needle begins to rise.
Needle lift start pressure: nozzle used 135-155 bar; new nozzle 145-155 bar.
Note: When the injector is working properly, a clear, distinctive cut-off sound should be heard.
If the needle lift start pressure does not correspond to the specified values, adjust it by selecting an adjusting washer of the required thickness.
Note:
- The adjusting washers have 43 sizes (thickness values) from 0.900 mm to 1.950 mm in 0.025 mm increments.
- Changing the thickness of the adjusting shim by 0.025 mm results in a change in injection pressure of approximately 3.5 bar (343 kPa).
- Only one adjusting washer should be used.
- When adjusting the injection pressure, use the data for the new injectors.
- d) After injection is complete, no fuel leakage should be observed.
2. Check the injector needle for leaks. Create a pressure of 10-20 bar on the injector testing stand (0.981-1.961 kPa) until the injector needle opens. There should be no fuel leakage from the nozzle hole or around the injector coupling nut for 10 seconds.
If fuel leakage is observed, replace or repair the injector.
3. Checking the cutting shape.
- a) Set the rotation speed of the fuel injection pump drive shaft (on the fuel stand) 15-60 rpm (used nozzles) and 30-60 rpm (new injectors).
- b) Check the correctness of the sawing shape of the jet.
