Several points that are easily overlooked in the repair and maintenance of diesel generator sets

I believe a lot of dieselGenerator setUsers all have such doubts. I have done every maintenance and repair, but why does the equipment still break down frequently or have a short lifespan? According to the summary of Haixing Power’s interactions with customers over the years, this is actually largely related to everyone falling into misunderstandings about maintenance and neglecting some small details. To sum up, we only did XXX and ignored XXX. Let’s take a look at some of the easily overlooked aspects of maintenance:

1. Only replace the plunger and oil nozzle, ignoring the technical status of the oil delivery valve. After the oil delivery valve is worn, the residual pressure in the high-pressure oil pipe will be too high, causing the fuel injector to cut off the oil and drip oil, causing the diesel engine to smoke from the exhaust, knock the cylinder, and run unstable. The method is to check the oil outlet valve and use a pressure gauge with a range of 0-600 kg/cm2. When the gauge needle drops from 200 kg to 180 kg/cm2, the pressure holding time should be greater than 15 seconds, otherwise the oil outlet valve should be replaced; or the oil outlet valve should be replaced; With the high-pressure oil pipe mouth facing upward, pump out the diesel fuel so that the oil level is flush with the pipe mouth. Return the throttle to the parking position and turn the wheel sharply for half a turn. If the diesel oil from the high-pressure oil pipe mouth does not suck back, it is considered qualified. Otherwise, the oil outlet valve should be replaced. .

2. Only adjust the valve clearance and ignore the valve timing. Most people just adjust the valve clearance according to the value specified in the manual, but neglect to check whether the valve timing is timing. Especially for older machines, due to changes in geometric shape after cam wear, the valves will open late and close early, which will lead to insufficient air intake, dirty exhaust, increased fuel consumption, and decreased power. Therefore, when adjusting the valve clearance of an old diesel engine, the valve clearance value should be appropriately reduced according to the mechanism to compensate for the valve timing error. For example, in the S195 diesel engine, every time the valve clearance decreases by 0.1 mm, the valve timing phase changes by 3 degrees. However, the valve clearance must not be less than 0.2 mm, otherwise it will be affected by expansion and cause the valve to not close tightly. If the valve clearance is already 0.2 mm, but the valve timing error is still more than 5 degrees, and the operating conditions of the diesel generator set have significantly deteriorated, the camshaft should be replaced.

3. Only look at the amount of oil in the oil pan and ignore the quality of the engine oil. Many people just replenish the engine oil and never check the quality of the oil or replace it. As everyone knows, the waste engine oil that should be replaced contains a large amount of oxidized substances and metal shavings, which will reduce the lubrication performance, increase the wear of the machine parts, and shorten its service life. Therefore, the quality of the engine oil in the machine should be checked at any time. The general method is to grind the engine oil with your hands. If you feel that there are mechanical impurities or the viscosity is not enough, you should replace it in time. Another check method is to drop used engine oil on white paper. If the black spots are small and light in color, with large yellow stains around them, you can continue to use them; if the spots are black and large, with no yellow stains around them, it should be replaced. .

4. Only know how to maintain the air filter and ignore the air short circuit. There are many reasons for air short circuit, such as the air inlet pipe of the air filter fixed on the tricycle frame is not welded properly, the gasket is not added to the joint of the air inlet pipe, the air inlet pipe is loosely inserted into the hose without a clamp, and the air inlet hose is broken without a clamp. It is found that there is a lack of rubber rings in the air filter, etc., which will cause an air short circuit, causing unfiltered air to enter the cylinder, aggravating the wear of the cylinder, piston, piston ring, valve and other mechanical parts.

5. Only clean the oil filter and ignore the cleaning of the purified oil chamber. The connecting rod journals of most diesel generator sets are hollow and have oil plugs at both ends, which are called purification chambers. Under the action of centrifugal force, the impurities of the engine oil that lubricates the connecting rod bearing stick to the cavity wall, thereby improving the lubrication quality. Generally, the oil plug of a diesel generator set must be removed every 500 hours of operation, and impurities in the oil cavity and oil passages should be cleaned according to prescribed methods.