Inspect your excavator engine?
Inspect your excavator engine?
5 Take Care of the cylinder check leak
Engine cylinder compression is a key factor affecting power shortage. The way to judge the compression is simple. Take the S195 diesel engine as an example: shake the crankshaft without decompression. When the compression force is large, shake it up and relax the handle, but do not leave the handle. There is a large rebound force, indicating that the compression force is good, and on the contrary, the compression force is poor. Then check the cause of the leak. The main cause of air leakage is that the cylinder is not sealed. In order to narrow the search range, when the engine is working, you can listen to the air filter first, if there is a "click" sound, if any, it means that the air leak is related to the valve; once again open the oil filler cap, if there is a stock The thick smoke of the stock emerged, indicating that the cylinder and the piston and the piston ring leaked.6 check the smoke color
When the engine is in normal working, it generally does not smoke or emit some light grayish white smoke, which is sometimes difficult to see with the naked eye. If the engine smokes smoke, it is a malfunction of the engine. This kind of failure will also affect the engine power drop, so it should be checked. Check the color of the smoke.
If smoke is a phenomenon in which the oil in the cylinder is less gas and the combustion is incomplete; the blue smoke is the performance of the cylinder sleeve and the piston, the valve and the valve guide, and the wear gap is too large, so that the oil in the oil pan is burned in the combustion chamber. White smoke is emitted from the exhaust pipe after the fuel is mixed with water and the completely unburned diesel oil is vaporized. The cause should be diagnosed and excluded.
7 check the fuel injection
Take a look at the fuel injection. Good fuel injection is not polarized, no oil drop, oil mist is uniform, and the range is appropriate. You can hear the crisp sound of “buzzling and smashing” outside the machine body. You can feel the fuel by hand touching the high pressure oil pipe. "Vibration" sense. This method can also diagnose the "vibration" force of the multi-cylinder machine and the working condition of each cylinder without the "vibration" force. If necessary, it can also be combined with the broken cylinder check to eliminate the symptom.
8 the fire to check the morning and evening
Seeing the fire head means whether the fuel injection is positive, that is to say, whether the fuel supply advance angle is in compliance with the regulations. Each model of diesel engine indicates in the specification the respective fuel supply advance angle. For example, the fuel supply advance angle of the S195 diesel engine is 15°-18°. This is because the diesel fuel needs to be mixed for a short time after being injected into the cylinder and heated to self-ignite. Therefore, the fuel should be injected into the cylinder before the piston reaches the top dead center in the compression stroke.
The fuel supply time in advance is expressed by the crank angle. The oil supply is too late (the advance angle is too small), the diesel engine is difficult to start, the combustion is not complete, the exhaust smoke is smoked, the machine temperature is too high, the power is insufficient; the oil supply is too early (the advance angle is too large), and the diesel engine has a knocking sound when working. Easy to damage parts, it is easy to reverse when starting, and it will also affect engine power. Therefore, the main meaning of ignition is to check whether the oil supply is too late or too early.