(1) Partial stop method. Stop the work of a certain part or system, and compare the changes of the fault symptoms before and after stopping the work to determine the faulty part or the faulty part. For example, use the cylinder breaking method on the engine to compare whether the parts of a certain cylinder are working normally.
(2) Cross-comparison method. When analyzing a fault, if there is any doubt about the technical state of a certain component, it can be replaced by a spare part with a normal technical state, and compare whether the fault symptoms have changed before and after the replacement, so as to determine whether the cause of the fault lies in the original component.
(3) Heuristics. Change the technical state in a local area to observe the changes of the fault symptoms to determine the cause of the fault. If the compression pressure of the cylinder is insufficient, it is suspected that the seal of the cylinder liner and the piston is poor, and a small amount of engine oil can be added to the cylinder. If the engine pressure increases at this time, it proves that the analysis is correct.
(4) Auscultation method. This method is often used to judge abnormal noise. Use a thin steel rod about 0.5 m long, one end of which is sharpened, touch the part to be inspected, and the other end is made into a circle and attached to the ear, so that the abnormal sound of the machine can be heard more clearly location and size. When the tractor is working normally, the sound it makes has its special regularity. Temperature, speed, load and lubrication conditions are the main factors affecting the sound. Some noises of the engine appear or increase with the increase of temperature; some noises weaken or disappear with the increase of temperature; some noises appear with heating phenomenon. The sound has a certain relationship with the engine speed and the running speed of the locomotive. Generally, when auscultating the engine sound, the accelerator is often changed, and when the chassis sound is auscultated, the vehicle speed is constantly changed. The sound of the transmission system generally increases with the increase of vehicle speed, but sometimes the situation is opposite. The load is different, the stress between the parts is different, and the sound will change. Generally speaking, the sound increases as the load increases, but some sounds weaken or disappear as the load increases. No matter what the noise is, it is loud when the lubrication is poor.
