Diesel coaster is the loss of speed control, rapidly increased to greatly exceed the rated speed, accompanied by severe vibration and a constant sound. If the diesel engine can not be stopped in an effective way when it coasts, it will cause major property damage and even cause casualties. The main reasons for the occurrence of speeding diesel engines are roughly the following two aspects: a large number of oil into the cylinder combustion; diesel oversupply. Although the performance of the engine is overspeeding, there are also differences. The exhaust pipe emits blue smoke; when the diesel oversupply causes speed, the exhaust pipe emits dark smoke. 1. The oil enters the cylinder and participates in the combustion. (1) The oil in the oil pan is added too much. A large amount of oil enters the cylinder through the gap between the cylinder sleeve and the piston. (2) There is too much oil in the air filter, which exceeds the scale line. Some of the oil directly enters the cylinder and burns from the intake port. (3) Piston ring wear, "pumping oil" role to strengthen. (4) The oil ring and the oil return hole on the piston are blocked, leaving the oil in the cylinder to burn. (5) The diesel oil leaks into the bottom of the oil, causing the oil level to rise, and the mixed oil enters the combustion chamber to participate in combustion. (6) The temperature of the diesel engine is too high, making the engine oil too thin and easy to enter the cylinder to participate in combustion. (7) The oil does not meet the requirements for use. 2. Diesel over-supply (1) The plunger is stuck in the maximum fuel supply position. The main reason: when assembling the plunger pair, the plunger is scratched; the tight torque of the oil valve is too large, so that the plunger sleeve is deformed; the gasket of the plunger sleeve positioning screw is too thin or the gasket is missed to make the plunger sleeve Deformation; the position of the rack member and adjustment gear is misplaced. (2) The possible causes of the governor: 1 The oil pump plunger adjustment arm does not fit into the governor lever fork, the plunger is in the maximum fuel supply position; 2 the pin and the key and other connectors drop off; 3 improper adjustment, Increase the pre-tightening force of the governor spring; 4 Adjust the device for adjusting the speed to the limit position; 5 When installing the governor flyball, apply too much grease and too thick, so that the flyball is difficult to open when the speed is increased. . (3) Insufficient oil supply due to injector quality problems. 3. Measures to be Taken After Speeding When a diesel engine takes off, it must be calm and calm, and first determine the exhaust color of the exhaust pipe. If you take blue smoke, you can take measures to block the intake pipe or open the decompression, because at this time the method of cutting off the diesel oil line is ineffective. If black smoke occurs, you can use a method to cut off the diesel oil line, that is, quickly loosen the coupling nut of the high pressure oil pipe; at the same time, block the air inlet pipe or open the decompression. If it is a tractor that is in operation while a moving motor vehicle is in operation, if it has a proper engine speed, if it has proper conditions, it may try to take measures to increase the diesel engine load and extinguish it. 4. Introduce a simple and effective way to check whether diesel may oversupply. Fix the throttle of the diesel engine at the flameout position, then shake the diesel engine. If the oil supply phenomenon still occurs, the speed may occur. Check until the fault is eliminated. Can be used normally.