Fault analysis of engine speed out of control of excavator
* : * : admin * : 2021-06-18 17:38:15 * : 10
In the maintenance of excavators, a very common problem is the engine speed out of control failure, commonly known as "flying car" phenomenon. In the maintenance of excavators at present, the situation of speed out of control is getting higher and higher, it will cause major accidents such as cylinder-pestle and broken axle in diesel engines. Diesel engines usually only appear runaway failure when they are just starting up or when the load suddenly disappears or lightens, and in the load below the work is not a runaway failure, the following we will analyze the maintenance of excavator speed out of control under the analysis. 1. The air filter has too much oil in it, gets sucked into the cylinder and Burns, which increases the fuel supply and speeds up the engine, causing the car to fly. 2, injection pump plunger coupling because the installation of skew or oil pollution stuck, but also can rotate the speed control rack to lose the boat, especially the multi-cylinder oil pump will appear load reduction, fuel supply can not be changed and cause flying situation. 3. The speed governor sliding sleeve of the single-cylinder diesel engine's single-unit fuel injection pump was stuck, which caused the speed regulation failure and led to the runaway failure. 4, some fuel injection pump plunger sleeve on the inlet and return hole in the same plane position, if the plunger sleeve positioning screw is too long to plug the return hole, it will cause the return oil is not free, resulting in increased fuel supply will also lead to flying. 5, fuel injection pump adjustment gear in the large fuel supply position or gear rack and governor pull rod out of control, will cause flying situation. 6. If there is too much lubrication in the governor case, the governor can not be thrown off quickly, which affects the function of the governor, causing the friction clutch of the Governor to slip, and loosening the governor's high speed limiting screws and safety gears, fast out or stuck, speed control spring break and thrust bearing or governor bearing damage, so that governor failure will lead to flying. If the diesel engine fails to stop and turn off immediately when flying occurs, it will cause serious consequences. Therefore, when flying occurs, we must find a way to make the diesel engine stop and turn off immediately, the emergency measures have the following: 1, plug the intake pipe, and then the diesel engine will not breathe in air flameout. 2, in the driving state can use high-grade heavy load, that is, the brake to reduce the engine speed and then flameout. 3. Put the throttle handle where the oil is not supplied and turn on the pressure relief so that the cylinder can be turned off without any compression. 4, with a wrench loosen the high-pressure oil pipe joint nut, so that the diesel engine does not supply oil, but also to let the diesel engine off.