Diesel generator set maintenance training diesel article -p156-p160

Diesel generator set maintenance training diesel article -p156-p160

If the amount of oil in the oil sump of the diesel generator exceeds the full scale of the oil scale, the oil splashed on the inner wall of the cylinder liner will increase, and some of the oil will enter the combustion chamber, which will cause the exhaust pipe of the diesel engine to blue during operation. The black smoke of the exhaust pipe of the smoke 2 diesel engine can be eliminated by the partition method. According to the method shown in Figure 5-2, the diesel engine cylinders are tested for oil cut-off. If the exhaust pipe exhausts black smoke after a certain cylinder is shut off, it indicates that the cylinder has a fault and the next inspection should be performed.

4 In the absence of an injector calibration table, remove the squirter from the cylinder head hole and fasten the injector to the high pressure fuel line, as shown in Figure 5-12. Start the diesel engine and observe the spray atomization quality of the injector. If the oil hole of the injector has drip oil, bleed oil, no fuel injection or poor atomization quality, replace the injector: if the injector is atomized well, remove the high pressure pump assembly. Then make corrections on the injection pump test stand.

5 As shown in Figure 2-71, place the high pressure oil pump assembly on the test bench, turn on the power, press the low voltage supply switch, then remove the air in the low pressure berth, turn the manual speed knob of the test bench, make the test The rotor rotates at a rotation speed of 750r/m blood and adjusts the docked measuring cup and presses the counter. Under normal circumstances, the 4135 diesel engine uses a B-type pump with a plunger diameter of 9 sides, and the pump supply volume is 25n6-/200 times. When there is too much or too little steam for the individual orders, and the fuel supply of each cylinder is not equal, adjustments should be made.

6 Fuel injection pump adjustment method for the oil supply star As shown in Figure 5-22, first loosen the locking screw of the adjustment gear, and then slowly push the adjustment hole on the oil control sleeve with a screwdriver of the appropriate size. When the single-cylinder oil supply exceeds the specified position o.5mL, it should be slowly pushed to the left; when the single-cylinder oil is less than the specified value of o.5mL, it should be slowly pushed to the right. Each time the amount of driving can not be too large, we must use the borderline test method until it meets the requirements.

7 If the cooling oil enters the oil in the oil pan, the combustor assembly should be disassembled and the components tested for tightness. After the cylinder head, cylinder liner, and cylinder head gasket are damaged, new parts are generally replaced without repair.

Fault 14: After the diesel generator diesel engine starts, it can be heard that there is a kind of very sharp and sharp golden crushed percussive sound machine in the upper part of the engine. When the speed suddenly collapses from high speed to low speed, it can hear a kind of “when, when” metal impact sound. Failure analysis:

This kind of failure is generally caused by the excessive clearance between the piston pin and the connecting rod small head bush or the looseness of the piston pin and the pin seat hole.

Method of exclusion:

1 As shown in Figure 5-23, remove the cover on the side of the machine body and turn the flywheel of the diesel engine so that the piston of the cylinder under inspection is turned to the top dead center of the compression stroke. Then, it is used to hold back the middle position of the connecting rod and watch it. Whether there is a feeling of wobbling in the piston pin area. If the piston pin is found to have a swaying feel and there is a metal impact sound, the cylinder piston pin or bushing is seriously worn.

2 Remove the cylinder head, remove the piston rod assembly, and inspect the piston pin or bush for severe wear. If the piston pin or bushing wears out, replace the bushing and trouble can be eliminated.

Fault 15: Diesel Generator Diesel Engine After Starting

Failure analysis:

When the diesel engine is in operation, a “travel” fault occurs when the speed is regularly and suddenly changed. This type of failure is generally caused by air in the ship's oil supply system, screen blockage in the oil circuit, or malfunction of the governor. The specific causes are: oil supply in the fuel injection pump regulates the seizure of the gear rod; oil supply in the fuel injection pump Adjusting the backlash of the gear rod is too large; the axial clearance of the camshaft of the fuel injection pump is too large; the adjustment of the spur gear rod in the fuel injection pump or the dialing of the rib pull rod is too loose: the active joint inside the governor is stuck or too loose; The internal spring of the governor is deformed or broken; the nozzle internal parts of the injector are burned to death: there is air or blockage of the filter in the oil circuit in the fuel supply system.

Method of exclusion:
1 During the operation of a diesel engine, there is a “leakage phenomenon” in the traveling car, whether the oil return screw of the spare interface is loose, and whether the filter is blocked.

In case of a fault, first check whether the fuel supply system is dirty with the diesel filter element and the oil pump is filled with oil.

2 If the fault is still not cleared after the above inspection, the fault is generally in the high-pressure oil pump assembly, the high-pressure oil pump assembly shall be removed and sent to the school pump center, and the maintenance personnel shall perform the calibration and repair on the special verification platform of the high-pressure oil pump. . Note: Diesel engine maintenance personnel who do not have the palm to improve the working principle of the pressure pump assembly generally do not arbitrarily disassemble, to prevent improper demolition and cause the governor to malfunction, causing a “fly” phenomenon when the diesel engine is tested.

Therefore, with the 16: diesel generator diesel engine abruptly stopped during operation, and the flywheel cannot be toggled for fault analysis:

The fault is usually caused by the stuck moving parts or the biting of the crankshaft and the bearing bush. The specific reasons are: the valve is stuck; the crankshaft and the bearing bush bite, namely “the holding shoe”; the main bearing cover is broken or the crankshaft is broken: the high pressure oil pump The drive shaft was stuck; the front gear drive of the diesel engine was bitten.

Method of exclusion.

When troubleshooting diesel engine diesel engines, specify a range and basically determine which component or system has failed and then disassemble it. For such faults, when the flywheel is pulled, it cannot be toggled. At this time, the fault range can be defined as the high pressure oil pump drive shaft is stuck, the front gear mechanism of the diesel engine is bitten, the crankshaft and the bearing shoe bite, the piston bites the cylinder, and The valve was stuck in five areas. In these five areas, we also need to go through in-depth inspections to narrow down the scope of faults.

1 Check the oil quantity and quality of the oil. The purpose is to check whether the crankshaft and the bearing shell bite, that is, "hold the wire." If the oil level is found after the oil gauge is drawn, it can be concluded that the diesel engine has the phenomenon of “holding the tile” when the amount of oil is below the “risk” value of the scale scale; if the quantity and quality of the oil meet the requirements, the diesel engine is generally considered to have appeared. The phenomenon of "holding the tile" should be checked for other items.

2 Remove the valve chamber cover and insert a flat-blade screwdriver between the valve and the rocker (as shown in Figure 5-24) to check if the valve is stuck in the valve guide.

2 Pull the flywheel of the diesel engine clockwise. If it cannot be pulled, turn the diesel flywheel counterclockwise. If you can pull it, it means that the piston does not have a biting accident. At this time, the fault scope should be demarcated in the high-pressure pump drive uranium is stuck qR diesel engine front gear transmission is bitten. In these two fault cities, the failure of the high pressure oil pump drive shaft to be stuck is easy to check.

4 Loosen the two captive screws (shown in Figure 2-75) on the drive shaft adapter plate of the high pressure pump assembly, and then manually turn the high pressure pump drive shaft. If it can not be turned, it means that the high pressure oil pump drive shaft is stuck. The high pressure oil pump assembly should be removed and sent to the professional school pump center for repair. If the drive shaft can be turned by hand, it indicates that the gear of the diesel front end gear transmission mechanism is Bite.

6 Remove the cover plate of the front gear unit of the diesel engine (see Figure 246). The purpose is to check if the gear is bitten or damaged. If the gear is damaged, replace the new gear of the same model: If the gear fastening screws are loose, remove the gears in pairs and repair them separately.