To explain why the color of exhaust fumes is not normal, the main components of normal combustion products should be carbon dioxide and a small amount of water vapor during the operation of the engine. If the engine in the excavator cab burns abnormally, the exhaust gas will be mixed with particulate carbon, hydrocarbons, carbon monoxide and a large amount of water vapor.From the exhaust smoke, we can see where the fault occurred.

　　In addition, there are nitrogen oxides and so on. At this time, the exhaust gas color may turn black, blue or white, which means that the exhaust smoke color is not normal. For gasoline engines, there should be no obvious smoke in the normal exhaust gas of the agricultural vehicle cab. However, when lubricating oil moves up the cylinder, the exhaust gas is blue, when combustion is incomplete, the exhaust gas is black, and when oil is mixed with water, the exhaust gas is white.

　　Excavator cab overheating high temperature usually occurs on engine, transmission, drive axle final drive, differential and brake assemblies. For example, engine overheating, mostly due to cooling system problems, lack of coolant or pump does not work, excavator cab transmission and drive axle overheating, mostly due to lack of lubricant, brake overheating, mostly due to non-return of brake iron pads,These phenomena can sometimes be directly reflected by a dashboard warning light, requiring the driver to observe them while driving, or to test the apparent temperature by hand.

　　Sudden change of working condition of excavator cab refers to abnormal working condition of cab, which is a common fault symptom. For example, it is difficult to start after engine suddenly stops, even can not start; power of engine suddenly decreases during driving and driving is weak; sudden braking failure or run-off or even failure during driving. The symptom of this fault is obvious.

　　The excavator cab shall provide convenient working conditions for the driver, comfortable driving conditions for the occupants, and protect them from vibration, noise, exhaust gas and bad weather while the excavator is driving. Some structural measures and equipment on the excavator cab also contribute to safe driving and mitigating the consequences of accidents.