Why Diesel Engine Can't Start?

The prerequisite for the normal operation of the 441KW 6 cylinder diesel engine is that well atomized diesel can be injected into the combustion chamber accurately and in time, and the compressed air in the combustion chamber must reach a sufficient temperature to catch fire and explode. To meet these two conditions, it is necessary to have a sufficiently high speed and a certain temperature in the cylinder when the diesel engine starts. When the diesel engine cannot be started, the cause should be found from the aspects of starting cooperation, diesel fuel supply system and compression.

If the water cooled 4 stroke diesel engine generator cannot start normally, it is recommended to do the following checks.

1. Improper procedures for starting operation steps of diesel generator set.

Solutions: According to the correct operation instructions, carry out safe and standard operation and start the diesel generator set.

2. The battery voltage is insufficient or the discharge current is insufficient.

Solutions: Charge the battery of the diesel generator set, or replace the battery to ensure that the diesel generator set has enough electricity.

3. The ambient temperature is too low.

Solutions: The cold starting fluid is an auxiliary starting fuel (composed of ether, low volatility hydrocarbons and low freezing point motor oil with additives), the added low freezing point motor oil with additives can improve the cylinder wall lubrication conditions to achieve the purpose of starting. Because ether has the features of good volatility, easy to ignite, and easy to ignite, the more the content of ether, the lower the temperature at which the high speed water cooled turbocharger diesel engine can be directly started, but the greater the roughness of the diesel engine when it is started. Therefore, when using cold starting fluid, it must be filled according to the prescribed amount, and must not be added in excess. Although this starting method can start the engine in an instant, due to the low temperature and high viscosity of the engine oil, there is not much oil on the cylinder wall for a period of time after starting, and the lubrication conditions are poor. The engine body reciprocates and rotates when the diesel engine is working, dry friction will form between the moving parts, which will aggravate the wear of the parts. Therefore, after starting the engine with cold starting fluid, do not increase the throttle operation. When selecting this starting method, you should choose a starting fluid with better atomization, and control the injection time, injection position and injection volume. In addition, do not spray the starting fluid directly from the air inlet of the air cleaner, so as not to affect the quality of the air filter element and increase the injection volume of the lifting fluid, which makes the engine to start running at a cold engine speed. According to the above instructions, it is recommended to use cold starting fluid with caution.

4. Check the smoothness of the oil path and replace the diesel filter if necessary.

Check whether the oil path from the oil tank to the oil transfer pump is leaked or blocked, whether the oil path is not smooth, whether the filter is blocked, and whether the oil transfer pump is fault.

5. Check the spray quality of the fuel injector.

Remove the injectors of each cylinder in turn and reconnect them to the corresponding high-pressure fuel pipes. Set the oil supply lever at the maximum oil supply position, use a special tool or a large screwdriver to pry the corresponding injection pump plunger, and observe the spray situation. For a good oil mist beam, the oil mist must be very uniform and fine, without obvious oil droplets and oil flow, and no unevenness in density. In addition, the oil cut is crisp and the cone angle and direction of the oil mist are normal. There is no oil dripping before and after spraying. The spray holes are dry or rarely wet after repeated spraying. If the spray quality of the fuel injector does not meet the above requirements, and the difference is far away, or when the injection holes of individual fuel injectors are blocked, it is difficult for the powerful 12 cylinder 4 stroke diesel engine to start.

In summary, the reasons for 441KW 6 cylinder turbocharger diesel engine starting difficulties and failures are many, so when dealing with difficult starting failures, we must first understand which of the three types of compression, operation, and oil supply the fault belongs to, and then according to the deeper manifestation of the fault to determine the cause. If the operation is not flexible, it may be caused by the tight coordination of the sports pair or the incomplete decompression. The small compression may be caused by the valve leakage. The main reason for the abnormal fuel supply may be the fuel injection pump and the fuel injector.