High Quality New Diesel Injector Nozzle DLLA144P2273 0433172273 0 433 172 273 Common Rail Injector Nozzle for Bosch Spare Parts

Fuel injector inspection process

The inspection of the needle valve assembly includes: surface visual inspection, sliding inspection, sealing inspection and spray inspection, etc.

3.1 The guide cylindrical surface of the needle valve and the injector body must not have obvious friction damage and scratches, and the sealing cone surface is complete.

3.2 Tilt the needle valve to a position of 45°, pull the needle valve out of the valve body by about 1/3, and it can slide slowly into the valve body under the action of its own mass without any sticking phenomenon.

3.3 Install the assembled fuel injector on the fuel injection tester, and adjust the spring pressure slightly higher than the standard opening fuel injection pressure of the fuel injector (generally 12~14MPa higher than 3~5MPa). If the oil pressure rises to 20MPa, measure the time it takes for the oil pressure to drop from 20MPa to 18MPa, not less than 9~12s.

Otherwise, the sealing performance is poor, and there must be no obvious oil droplets around the nozzle hole. When there is no fuel injector tester, the repaired fuel injector can be directly installed on the fuel injection pump of the diesel engine for testing.

3.4 Adjust to the specified fuel injection pressure of 12MPa, and pump oil at a pump speed of about 60～70 times/min. The sprayed fuel should be finely and evenly atomized, and there should be crisp and intermittent chirping sounds. There is no oil dripping phenomenon, and there is no serious leakage around the nozzle hole of the injector body.

Put a piece of white paper 10~20cm away from the nozzle under the injector, and measure the distance h from the nozzle to the oil stain and the diameter d of the oil stain. Then calculate according to the formula.

Find the angle from the trigonometric function, and twice the angle is the fuel injection cone angle. If the requirements cannot be met through the above work, a new fuel injector should be replaced.

Finally, the following points should be noted:

(1) Pay attention to the above code when using the fuel injector to avoid using it wrongly. Otherwise, the ideal requirements will not be obtained, the fuel will be incompletely burned or not ignited, black smoke will be emitted from the exhaust, fuel will be wasted, and power will be affected.

(2) When correcting the fuel injection pressure, never let the skin or fingers come close to the nozzle hole and be injected by the injected fuel. Because high-pressure diesel oil penetrates the skin and flows into the blood vessels, it will have a poisonous effect on the human body. Special attention must be paid to never observe the fuel injection situation too closely to prevent damage to the eyes.