Diesel generator set maintenance training diesel article -p141-p145 fault judgment

Diesel generator set maintenance training diesel article -p141-p145 fault judgment

Fault 5: When diesel engine diesel engine starts, it can hear the impact sound of the rejection wheel and flywheel tooth pattern inside the starter, but the diesel engine cannot start failure analysis:

This kind of failure is generally caused by the failure of the flywheel or gear of the starter to be engaged with the flywheel ring gear of the diesel engine or the slipping of the starter's one-way clutch. The specific reasons are: the static contact and the movable contact within the magnetic switch are closed prematurely. ; Starter internal rejection wheel or flywheel tooth group excessive wear s one-way clutch slipping and so on.

Method of exclusion:

1 Use a screwdriver to pull the diesel flywheel to change the meshing position of the flywheel ring gear and the thrower wheel. Pulling the flywheel The diesel engine still cannot start. Check the next step.

2 As shown in Figure 2-3l, adjust the adjustment screw of the lower left end of the magnetic switch of the starter so that the distance between the starter fly-out wheel and the flywheel ring gear of the diesel engine is small and easy to mesh. If the diesel engine cannot be started after adjustment, other inspections should be performed.

3 Remove the starter,

Replace the new one.

Check the starter's one-way clutch, flywheel ring gear and flywheel. i. When starting with 6I diesel engine, the starter will not turn and the magnetic switch will be heard.

This kind of failure is generally caused by the lack of battery power and bad.

Method of exclusion:

Poor contact of control circuit of diesel generator set or internal loss of starter

1 As shown in Figure 5-8, use a multimeter (DC voltage block) to measure the voltage difference between the battery before starting and when it starts, to determine whether the battery power is sufficient. If the voltage difference is more than 2v, it indicates that the battery power is insufficient. If the voltage difference is less than 2v, it indicates that the battery power is sufficient, and the next step should be checked.

2 Remove the switch terminal and the battery terminal. Then use a multimeter to block (R×1) the resistance of the control circuit, as shown in Figure 5-9. If the measured resistance is more than 20KΩ, it means that the control circuit and the magnetic switch have not failed: If the resistance of 5111 is very small, check the next step.

3 Check whether there is any poor contact between the brush and the commutator, as shown in Figure 5-10. If the contact is good, the starter should be disassembled for inspection.

4 After the starter is disassembled, first check the distance between the ends of the fork and the slip ring. If the distance is too large, it will cause the shifting fork to not be able to shift the gear (or throwing wheel) into engagement with the flywheel ring gear and adjust the spacing; if the distance between the two ends of the shifting fork and the slip ring is appropriate, check whether the electric coil is winding. There is an open circuit or a short circuit. If the armature winding fails Fault 7: The diesel engine sinters during work in winter.

The internal static contact and moving contact of the magnetic switch may be poorly contacted or

This failure is generally due to a long start-up time,

Caused by.

Method of exclusion:

1 Fill the water radiator with hot water and use winter oil to reduce the starting resistance. 2 During the start, you can inject the starting spirit into the intake pipe to shorten the starting time.

The magnetic switch on the upper part of the 22135 starter allows the DC voltage to pass through to be about 14V. When starting the diesel engine in winter, in order to meet the starting requirements, the original one helium battery start can be changed to two 6Q-195 helium galvanic oil parallel starters. The purpose is to use the method of increasing the ionic battery capacity for the diesel engine under the same voltage. start. This kind of starting method is not easy to make the static contact and the moving ship point inside the magnetic switch contact bad or twisted together.

1 Use a large flat-blade screwdriver to pull the diesel flywheel more than four turns to reduce starting resistance.

Therefore, with the 8: diesel engine in the idling operation, heard a clear "singing, singing" sound failure analysis:

This sound is a valve knock. When the diesel engine is running at a low speed, it is easy to hear a continuous, slightly, slightly "crouching" sound. As the speed increases, the sound increases. This failure is caused by incorrect adjustment of the valve clearance.

Method of exclusion;

Remove the diesel valve housing cover and inspect and adjust the valve clearance as described in Chapter 4.

Second, diesel generator set 4135 diesel engine troubleshooting examples

It is 1: Lake diesel engine start, the starter does not rotate

Failure analysis:

When starting the diesel engine, the starter does not rotate. There are two situations:

One is to hear the sound of the magnetic switch, but the starter does not rotate. This kind of failure is caused by insufficient battery power, poor starting circuit contact, or damage to the internal drive components of the starter; the other case is magnetic force. The switch does not pull in, and the starter does not rotate. This failure is usually caused by a tripping of the start circuit, poor internal contact of the magnetic switch, or damage to the starter.

Method of exclusion:

Inspect and repair the common starter failures as described in Section 7 of Chapter 2 of the technique.

As a result, the exhaust pipe continued to emit blue smoke after the diesel generator set started.

Failure analysis:

This kind of failure is a kind of comprehensive failure. The reason for this is generally that part of the oil penetrates the combustion chamber and is vaporized by high temperature and high pressure to form steam, and then discharged with the exhaust gas. If the oil is burned, it will cause the blackhead to hold the gas. This will increase the carbon deposition in the combustion chamber and increase the consumption of oil. When the internal nozzle of the nozzle is jammed or the oil hole is blocked, the exhaust pipe will also take a blue marriage. The specific reasons are: the oil passing through the Xu valve stem and the internal valve guide of the cylinder head is too large between the damage, so that the valve is lubricated. The engine oil of the mechanism is sucked into the combustion chamber; the wear interval between the piston ring, piston and cylinder liner is too large, causing the oil to enter the combustion chamber: too much oil in the oil pan; the piston ring is cemented in the piston ring groove. The lack of elasticity of the piston ring, the opening of the piston ring is not staggered, and the oil ring is installed in the opposite directions in the up and down direction; the new diesel engine or overhauled diesel engine has not been fully run-in, resulting in poor sealing of the cylinder.

Method of exclusion:

1 Check the oil viscosity, quality and amount of mooring. If the engine oil is not replaced for a long time and it becomes thin or the engine oil is too heavy, it will cause some oil to enter the room, causing the exhaust pipe to emit blue smoke after the diesel engine starts and will cause the diesel engine power to drop. It is required that the degree of oil drilling be in compliance with the regulations. The amount of oil should reach the full scale of the oil scale before starting the diesel engine, and there should be no impurities in the oil. If it does not meet the above requirements, the oil should be changed or the amount of oil adjusted, so drop it out.

2 using the method of cutting off the range of small antimony. After the diesel engine is started, one of the four cylinders is stopped by the field breaking method. The high pressure oil pipe in the upper part of the high pressure oil pump or the cover plate of the inspection port of the high pressure oil pump is opened with an open end wrench. The pulsator body of the high-pressure oil pump sub-pump was taken up, as shown in Figs. 5-1 and 5-2, to observe the change of the operating state of each cylinder before stopping the supply of oil and stopping the mooring. If Raleigh's cylinder stops supplying fuel, the blue marriage phenomenon disappears or weakens, indicating that the fault is in the cylinder. If the phenomena of disconnecting the blue pipe of the holding pipe after mooring of each cylinder are not eliminated by the trapping method, it means that the failure is not caused by the individual cylinder, but the cause of the failure which has an influence on the preparation cylinder is searched or performed. Other checks.

3 If the phenomenon of blue smoke emitted from the exhaust pipe of the diesel engine does not disappear after the fuel supply to each cylinder is stopped by shutting off the oil, the diesel engine should be stopped. After 10 mh, the diesel engine is restarted, and then the rows of the cylinders are each touched by hand. Short tube, as shown in Figure 5-ll. If the temperature of the exhaust pipe of an individual cylinder is lower than the temperature of the exhaust pipe of other cylinders, the injector assembly of the cylinder should be disassembled.

4 Connect the disassembled fuel injector assembly to the high pressure fuel pipe (see Figure 5-12), start the diesel engine to idle speed to check the sprayer atomization quality. If the fuel injector does not spray fuel, it should be Replace the injector. When the nozzle is clogged, the exhaust pipe will emit blue smoke when the diesel engine starts. If the temperature of the exhaust pipe of each cylinder during the operation of the diesel engine is basically the same, other items should be checked.