Common rail system components are sensitive to the water in the fuel system, especially those components like common rail injector with precision control valve that are lubricated by diesel themselves.Once the water enters the system it may cause problems such as corrosion of components or poor lubrication.Below there are some main faults & problems in the common rail injectors we usually experienced:

 

1.Poor atomization of fuel injector

Diesel engine power down, exhaust black smoke

When the oil injection pressure is too low, the carbon deposition, spring-end wear of the spring-hole or the drop of the spring force will cause the injector to open earlier, close later, and form an undesirable spray atomization phenomenon.

 

2.Needle valve stuck

Engine power down, jitter, even can not start

When moisture or acid in diesel cause the needle valve to rust and get stuck,the cylinder seal cone is damaged, the combustible gas in the cylinder will also enter the matching surface to form carbon deposit, causing the needle valve to stuck, the injector will lose the function of oil injection, causing the cylinder to stop working.

Tip:Remove the injector, take out the injector nozzle and pull out the needle valve with tools. If it is not easy to pull out, put the nozzle into diesel oil for about 20 minutes to be heated before taking it out.

 

3.Needle valve and needle valve orifice wear

Reduced power makes it difficult or even impossible to start the engine

The needle valve moves back and forth frequently in the needle valve hole.Meanwhile the intrusion of impurity pollution in the diesel oil will gradually wear the needle valve hole guide surface, so the gap increases and the scratch mark appears, resulting in increased leakage in the injector, pressure reduced,fuel injection quantity decreased, lag in fuel injection time, causing the engine starting difficulty.When the injection time delays too much, the diesel engine cannot even run.So you need to replace the needle valve coupler.

 

4.The nozzle drips oil

When the temperature of the diesel engine is low, it is difficult to start, and the exhaust pipes have white smoke. When the temperature of the diesel engine rises, it turns to black smoke.High fuel consumption.

 

When the common rail injector is working, the sealing cone of the needle valve body will be frequently impacted by the powerful force of the needle valve, together with the constant injection of high pressure oil from the point, the cone will gradually wear or spots, thus causing the injector to drip oil.When the diesel engine temperature is low, the exhaust pipe will emit white smoke, and when the diesel engine temperature rises, it will become black smoke.Check whether the movement of needle valve is flexible and the cone should be free of wear.Or you need to change one new common rail nozzles.