Inspection method for working condition of diesel engine cylinders
The working condition of each cylinder of the diesel engine can be checked by the following method at idle speed:
(1) listen and act: with a stethoscope or with metal rods, near the site of the injector body, listen to each cylinder explosion sound, normal is similar to the sound of metal percussion sound "Dangdang". If only the "Ho" discontinuous crisp sound, the cylinder oil supply too little or no timely ignition, such as percussion sound great, indicating that the cylinder oil supply amount is too large or injection time is too early.
(2) the color method: the diesel engine works normally, the exhaust gas color is light gray, the load is slightly deeper. If the exhaust gas, the fuel gas combustion is not completely. Exhaust smoke, shows that the lubricating oil into the cylinder combustion. White smoke, the diesel engine is described in the water, the fuel gas is not burning white smoke. The exhaust pipe of continuous discharge abnormal color, indicating the individual cylinder not working properly.
(3) temperature: in the initial stage after starting the engine (after a period of time with the exhaust pipe temperature is very high, by hand touch will touch the cylinder exhaust pipe burn temperature, identification of the cylinder. If the temperature of each cylinder exhaust pipe is higher than other cylinders, indicating that the cylinder oil supply is high; if the temperature is low, then the cylinder fuel supply is low, or not injection, or after the injection is not completely burning or not burning.
(4) pulse method: hand pinch the high-pressure oil pipe, feel the pulse of the fuel injection situation, the pulse is small, the sound is weak, the temperature is low, the cylinder oil supply amount is small. Abnormal sound and high temperature of the fuel injector fuel injection pressure drop, poor fuel injection atomization, or can not be timely fire and complete combustion. Pulse big, strong, high temperature, the temperature of the cylinder for a large amount of oil. Sound weak and low temperature for fuel injector hole or needle stuck.
(5) off oil method: in order to accurately determine which cylinder is faulty, can cut off the high pressure oil pipe to the injector circuit by cylinder, that is, stop working, to observe the change of the diesel engine working conditions. When cutting a cylinder oil, if the engine speed and sound no change or change is not large, indicating that the cylinder is working properly. If the intermittent knocking cylinder, black smoke, when cut off the oil circuit of a cylinder, the failure phenomenon disappeared, then explain the fault in the cylinder.