1. Use lubricating oil with proper quality grade.
For gasoline engines, SD-SF gasoline engine oil should be selected according to the additional devices and service conditions of the intake and exhaust system; CB-CD diesel engine oil should be selected according to the mechanical load, and the selection standard should not be lower than the requirements specified by the manufacturer.
2. Change the oil and filter element regularly.
The quality of lubricating oil of any quality grade will change during use. After a certain mileage, the performance will deteriorate, which will bring various problems to the engine. In order to avoid failure, the oil should be changed regularly according to the use situation, and the oil quantity should be moderate (generally, the upper limit of the oil meter is better). When the oil passes through the holes of the filter, solid particles and viscous substances in the oil will accumulate in the filter. If the filter is blocked, when the oil can't pass through the filter element, it will burst the filter element or open the safety valve, and through the bypass valve, it will still bring the dirt back to the lubrication part, causing engine wear and aggravating internal pollution.
3. Keep the crankcase well ventilated.
At present, most gasoline engines are equipped with PCV valve (crankcase forced ventilation device) to promote engine ventilation, but pollutants in blowby will deposit around the crankcase forced ventilation valve, which may block the valve. If the PCV valve is blocked, the polluted gas will flow back to the air filter [/k0/], which will pollute the filter element and reduce the filtering capacity. If the inhaled mixed gas is too dirty, it will further cause crankcase pollution, increase engine oil consumption, increase engine wear and even damage the engine. Therefore, it is necessary to maintain the PCV regularly to remove pollutants around the PCV valve.
4. Clean the crankcase regularly.
During the operation of the engine, high-pressure unburned gas, acid, water, sulfur and nitrogen oxides in the combustion chamber enter the crankcase through the gap between the piston ring and the cylinder wall, and mix with the metal powder produced by the wear of parts to form sludge. When the amount is small, it will be suspended in the engine oil, and when the amount is large, it will be separated from the engine oil, blocking the filter and oil hole, causing engine lubrication difficulties and wear. In addition, when the engine oil is oxidized at high temperature, it will form paint film and carbon deposit, which will stick to the piston, increase fuel consumption and reduce engine power. In severe cases, the piston ring will get stuck and the cylinder will be pulled off. Therefore, it is necessary to regularly clean the crankcase with BGl05 (efficient and quick cleaning agent for lubrication system) to keep the engine clean.
5. Clean the fuel system regularly.
In the process of supplying oil to the combustion chamber through the fuel pipeline, colloids and carbon deposits will inevitably form. These colloids and carbon deposits will be deposited in fuel pipelines, carburetors, fuel nozzles and combustion chambers, which will interfere with fuel flow, destroy the normal air-fuel ratio, cause poor fuel atomization, and cause engine jitter, explosion vibration, unstable idle speed and poor acceleration. Cleaning the fuel system with BG208 (a powerful and efficient cleaning agent for fuel system) and regularly controlling the generation of carbon deposits with BG202 can always keep the engine in the best condition.
6. Maintain the water tank regularly.
Rusting and scaling of engine water tank are the most common problems. Rust and scale will restrict the flow of coolant in the cooling system, reduce heat dissipation, lead to overheating of the engine and even damage the engine. The oxidation of cooling liquid will also form acidic substances, which will corrode the metal parts of the water tank and cause damage and leakage of the water tank. Cleaning the water tank regularly with BG540 (powerful and efficient water tank cleaner) to remove rust and scale can not only ensure the normal operation of the engine, but also prolong the overall life of the water tank and the engine.
Brake pedal method
First, hurry first and then stabilize.
In case of emergency, first step on the first brake quickly, then step on the second brake slowly, and then slowly release the brake pedal according to the distance of the situation, and change into a suitable gear according to the vehicle speed, so as to keep up with the accelerator and resume normal driving, that is, after the first brake, when the vehicle nods and just begins to return to its original position, step on the second brake to make it unable to return to its original position quickly, and then slowly release the brake pedal, thus reducing the front and rear impact caused by the rapid change of vehicle speed.
Second, the continuous braking method
In case of an accident, step on the accelerator to slow down in advance, and at the same time, step on the brake pedal slowly and continuously. This kind of early deceleration braking reduces the harm caused by emergency braking, but beginners of this braking method should use it with caution.
Three, dragonfly water braking method
This braking method is usually used on rainy or muddy roads. It brakes bit by bit like a dragonfly. This braking method can reduce the directional loss caused by wheel locking. Vehicles equipped with anti-lock braking system do not need to do this.
It is not a dream that the engine of 500 thousand kilometers will not be overhauled. For a certain brand of automobile, because the same spare parts are used, unified quality control standards are followed, and the same production line is assembled according to strict technological process, the performance indexes of each engine are not much different. But in actual use, the service life of each engine is different. Some engines can use 500,000 kilometers without overhaul, and some engines use less than 65,438+10,000 kilometers. The engines will emit black smoke and burn engine oil. Why are the products produced by the same production line so different?
The key lies in the correct use and maintenance of the car.
Then, in the daily use of cars, how can we do the correct operation and maintenance?
1. Pay attention to the running-in period of the new car.
During the running-in period of a new car, the uneven surface of the internal parts of the engine will be worn off, gradually forming a relatively smooth working surface, improving the surface quality and matching accuracy of the parts under normal working load. Therefore, the working condition of the engine during the running-in period is directly related to its service life. Attention must be paid during running-in of vehicles.
(1) It is forbidden to drive at high speed. The driving speed of the car in each gear shall not exceed 70% of the maximum engine speed. It is not allowed to drive at high speed for a long time.
This is forbidden? Overloaded operation, not overloaded. Once the engine is not running smoothly, shift to low gear immediately.
(3) After the engine has just started, it is not allowed to slam on the accelerator, and then start it smoothly after the water temperature reaches the normal working humidity. You must use first gear when going straight.
(3) Don't drive on bad roads to reduce vibration and impact. Overload caused by sudden acceleration should be reduced during driving, such as emergency braking, long-term braking or engine braking. Try to choose a good road surface to drive at a constant speed, and the running-in effect is the best.
5] Pay attention to the engine coolant temperature and lubricating oil level. , and timely troubleshooting.
[6] After the running-in period, carry out a running-in maintenance for the car.
2. Insist on preheating the car before starting.
Some drivers are often forced to step on the accelerator several times after starting the car to make the engine run quickly. As we all know, doing so will cause great damage to engine parts. Because when the engine is started (especially cold start), the working humidity of the engine is low, and the surfaces of internal parts are not fully lubricated. If the engine works under high load at this time, the wear of internal parts will increase and the normal fit clearance will change.
A good driving habit should be to preheat the engine coolant to normal working temperature (at least above 50℃) after starting the engine, and then make progress.
Have a good start.
Starting requires a low gear, and the key to ensure a fast and stable start is whether the oil distribution and cooperation are appropriate. When releasing the clutch pedal, it will be faster once, stopped twice, released four times in slow three. Several processes, that is, when starting, the clutch pedal should be released quickly; When the clutch is in semi-clutch state, stop for a while and refuel properly; Then slowly release the clutch pedal until the clutch is fully engaged; After the vehicle starts smoothly, quickly release the free stroke of the clutch pedal. The above process should be completed quickly, and more training should be done at ordinary times. The clutch half-clutch time should not be too long to avoid excessive wear of the clutch friction plate. Of course, for an automatic car, the above clutch operation is unnecessary.
4. Develop correct driving habits
Many people don't want to refuel while driving. On the one hand, urban roads are complex and changeable, and the speed cannot be improved. On the other hand, it is wrongly believed that the smaller the engine load is, the more fuel-efficient it is, which leads to the engine always running at idle speed and light load.
In fact, the lower the engine load, the higher the fuel consumption. Moreover, at this time, the engine is not fully burned, which is easy to produce carbon deposit, and the engine power is not fully utilized. With the development of engine technology, high-speed gasoline engines are widely used in automobiles. When the engine speed is 2500r/min, the output torque, power and fuel consumption of the engine are in good condition, and the economy and power are good. Therefore, when driving, we should make full use of the best working state of the engine, pay attention to the tachometer, and control the engine speed by choosing the appropriate gear. When driving normally, the engine speed should be around 2500 rpm, and it should be higher than 2500 rpm when upshifting. High-speed and low-speed driving or low-speed and high-speed driving are not allowed. Grasping the shift timing is an important index to measure the driver's driving level.
5. Regular maintenance
Three-point culture and seven-point culture &; Current situation; No matter how advanced the car is, it needs good maintenance to play its excellent performance. In the special maintenance station designated by the automobile manufacturer, regular inspection and maintenance must be carried out in strict accordance with the prescribed mileage items, so as to eliminate all kinds of hidden dangers of the automobile in time and ensure that the automobile is in good working condition, and at the same time, high-quality fuel and lubricating oil designated by the original factory must be selected.
Quick reversing skills for beginners
Before reversing, look at the situation behind the car, estimate the reversing route and judge whether there will be obstacles in front of the car. Try not to step on the accelerator when reversing, and control the speed not too fast.
Turn the steering wheel in the direction of the rear of the car with your left hand: if the rear of the car needs to drive to the right, turn the steering wheel to the right; Otherwise, turn the steering wheel to the left. In fact, this is consistent with the steering action when the car is driving forward. Keep this in mind, and you won't be in a hurry because of the wrong direction.
Don't keep looking behind the car when reversing. On the premise of ensuring the safety behind the car, observe the left and right rearview mirrors from time to time, pay attention to the distance between obstacles and the car body, and use the steering wheel to correct the car body position when the car body retreats accordingly.
If you think that the front of the car may encounter obstacles when reversing, then you need to look at the front of the car at the right time. Especially in the case of large steering wheel turning range, because the turning radius of the steering wheel is larger than that of the rear wheel, the turning range of the front of the car is also large when reversing, so pay attention to the front of the car to avoid bumps.
Don't get into the habit of hitting the steering wheel in situ, it is easier to damage the vehicle and it is also very troublesome to fight.
About hot cars
The main reason for the decline of automobile engine performance is wear, and the most serious engine wear is cold start, especially in winter. "Car" is the performance of many drivers' cars, but not all engines can be warmed up. According to the instructions, it is best to start the cold start car immediately after landing, so that all components can be heated at the same time, but remember not to drive directly at high speed. It is best to drive at a low speed 1-2 km, and then slowly accelerate after the water temperature rises to the lowest line. Some vehicles indicate that they should be warmed up after starting, but be careful not to control the engine with foot oil when warming up. Manual shock absorbers should be used to stabilize the vehicle. Low water temperature is not good for the engine, while high temperature will dilute the lubricating oil, which will not form a good lubricating oil film and increase the wear of parts. And it is preferable to use a fuel grade higher than that required by the vehicle. Using low-grade fuel will knock the engine and strongly impact the cylinder wall and parts, thus accelerating the wear of parts. In addition, impurities in low-grade fuel will also destroy the lubricating film and accelerate the wear of parts. The choice of lubricating oil is also based on the requirements of the engine itself, but remember not to choose lubricating oil with too high or too low viscosity. No, the more lubricant, the better. Once the lubricating oil is filled too much and the oil level is too high, it will not only increase the motion resistance and reduce the power, but also cause the lubricating oil to burn into the cylinder, resulting in excessive carbon deposition. Lubricating oil should be filled according to the quantity indicated by the dipstick. You'd better not drive on bad roads. Some people think that low speed can protect the engine, but it is not. When the vehicle speed is low, the lubricating oil power is also low, the oil film rigidity is small, and the lubrication condition is poor, which will aggravate the wear. In addition, at high speed, the average speed of the piston is larger. Therefore, the wear of the cylinder block is great. It is best to keep the economical speed when driving and control the speed through the gearbox. Only in this way can the engine reach its best condition. Maintenance is also an important measure to prolong engine life. Cleaning the oil filter is very important. If there is a problem with the "three filters", impurities will enter the engine and aggravate the wear. In a word, the correct driving method and reasonable maintenance are the key to prolong the engine life.
Driving style and tire wear
1. Tire pressure
This is the fate of pneumatic tires. Too high or too low will shorten its service life. When the air pressure is too low, the deformation of the carcass will increase, cracks will easily appear on the sidewall, and warping will occur at the same time, resulting in excessive heat generation, rubber aging and tire cord and cord breakage. Too low air pressure will increase the contact area of the tire and accelerate the wear of the shoulder. If the air pressure is too high, the tire cord will be excessively stretched and deformed, the elasticity of the tire carcass will be reduced, and the load of the automobile will be increased. If hit, internal rupture and explosion will occur. At the same time, too high air pressure will wear the crown and reduce the rolling resistance.
2. Front wheel alignment
The front wheel alignment has a great influence on the service life of the tire, especially the toe-in and camber of the front wheel. The camber angle of front wheel will mainly accelerate the wear of shoulder, that is, eccentric wear; Too small and too large toe-in of front wheel is mainly to accelerate the internal and external wear of tire.
3. Driving style
When driving, we should not only deal with the situation, but also choose the road surface, avoid sharp stones, glass, metals and other objects that may puncture and scratch the tires, and avoid the adhesion and corrosion of chemicals splashed on the tires. When driving on roads with large camber, try to drive in the middle to reduce uneven tire wear caused by the increase of tire load on one side. Generally, 20% overload will reduce tire life by 30%, and 40% overload will reduce tire life by 50%. In addition, sharp turns, emergency braking, high-speed starting and rapid acceleration will all have an impact on tire damage, which drivers should avoid while driving.
Before driving every day, Ning should check:
1. Visual inspection
Before getting off the bus, look around to see whether the lighting device is damaged, whether the car body is tilted, and whether there is oil leakage or water leakage. Check the tire appearance; Check the condition of doors, hood, rear compartment lid and glass.
2. Check the signal device
Turn on the ignition key (don't start the engine), check the lighting of all alarm lights and indicator lights, start the engine, and see if all alarm lights are off normally and the indicator lights are still on.
3. Fuel inspection
Check the description of the fuel gauge and replenish the fuel.
What should I check every week:
1. Check the tire pressure, adjust the tire pressure, and clean the sundries on the tire. Don't forget to check the spare tire.
2. Engine and various oils
Check the fixing of engine parts, and check whether the engine joint surface leaks oil or water; Check the belt tightness; Check the fixing of pipes and wires in each part; Check the oil replenishment; Check the coolant; Check the electrolyte; Check the auxiliary power steering oil; Clean the outside of the radiator; Add windshield cleaning solution, etc. ?
3. Clean the interior and exterior of the car.
What should you check every month:
1. Conduct external inspection on patrol cars to check the damage of light bulbs and lampshades; Check the fixing of body accessories; Check the condition of the rearview mirror.
tired
Check tire wear and clean luggage compartment; When approaching the tire wear trace, replace the tire and check whether the tire has bulging, abnormal main wear, aging cracks, hard damage, etc.
3. Clean, wax and thoroughly clean the car; Clean the sundries outside the water tank, oil radiator and air radiator.
4. Chassis
Check the chassis for oil leakage. If oil leakage is found, check the gear oil quantity of each assembly and make appropriate replenishment, and make adequate grease replenishment for all the oil nozzles on the chassis.
Speed and fuel consumption
Drivers are more concerned about the fuel consumption of cars, especially at present, with the rising price of gasoline and the imminent collection of fuel tax, the fuel cost of cars has become a part that car owners have to pay more and more attention to. There are many posts on the forum about how to save fuel. Next, I mainly talk about how to save fuel from the aspect of reasonable control of vehicle speed.
1. The higher the rotating speed, the greater the power and utilization ratio, and the smaller the fuel consumption. So cars consume more fuel at low speeds. ?
When the vehicle speed is too high, the fuel consumption is also high, because when the engine speed exceeds the minimum fuel consumption, the fuel consumption increases with the increase of the vehicle speed. When the vehicle speed exceeds a certain level, the fuel consumption increases rapidly. These factors will increase the unit fuel consumption when the vehicle speed increases. So too high or too low speed is not conducive to fuel saving. ?
2. In order to master the economical driving speed, the driver should learn to use the engine tachometer and speedometer to increase or decrease the throttle opening appropriately, and keep the engine working in the range of 30%~70% according to the road conditions. ?
3. Avoid sudden acceleration and deceleration when driving. Sudden acceleration consumes 1/3 more fuel than smooth acceleration. Some imported automobile carburetors are equipped with deceleration sliding refueling valves and throttle buffers, and the fuel supply will continue or increase at the moment of deceleration. Therefore, in order to save fuel, we should try to keep the speed stable and avoid sudden acceleration and deceleration. ?
4. Use the inertia of the car as much as possible to reduce unnecessary braking. Pay attention to roadblocks when driving, which can be used as a substitute brake to reduce fuel consumption. Because emergency stop and start will consume about 35 ml more gasoline. Never use the characteristics of imported cars such as sensitive braking and fast acceleration to deal with the situation, reduce braking times and avoid dangerous situations.
5. Correct use of patrol equipment. Some imported cars are equipped with patrol control devices. When driving on a road with good and uncomplicated road conditions, patrol control devices should be used to stabilize the vehicle speed at an economical speed to achieve the best fuel-saving effect. ?
6. Reasonable utilization of air refrigeration system. When the vehicle speed is lower than 85km/h, turn off the air refrigeration system and open the window for ventilation. However, when the vehicle speed is higher than 85km/h, make full use of the air conditioner to cool down and do not open the window. Increasing wind resistance after high-speed window opening consumes more oil than air refrigeration system. ?
7. Use car instruments. Keep the engine running economically, observe the instructions of various instruments at any time, and keep the engine working at the economic speed as required to achieve the purpose of saving fuel. ?
8. Keep the car clean and tidy. Reduce the weight of the car body, clean up unnecessary items on the car and dirt on the chassis in time, and reduce the weight.
Five causes of engine wear:
Famous American engineer Robert? In the book "Ride It Forever", Kosky listed
Five causes of engine wear:
I. Corrosion and wear
Many harmful substances will be produced after combustion in the engine combustion chamber. Generally speaking, every 100 gallon of gasoline will produce 1-5 pounds of nitrogen and sulfuric acid. These substances will not only corrode the cylinder, but also run into the engine through three piston rings (top ring, middle ring and bottom ring), causing metal corrosion to the main parts of the engine, such as the cam crankshaft. This kind of corrosion can't be eliminated only by using lubricating oil.
Second, corrosion and wear.
After the engine is stopped, it is cooled from high temperature to low temperature. This temperature change process will lead to condensate gas or even water accumulation inside the engine. This will cause serious metal corrosion to the engine, especially if the engine is restarted in a short distance and the engine temperature is too late to evaporate water vapor. This cannot be solved by lubricating oil.
Third, the strong wear and tear caused by dust
When the engine burns, it needs to take in air. No matter how good the air filtration device is, it is difficult to absolutely prevent dust from being sucked into the engine with the air. Because dust is inhaled, causing strong wear, lubricating oil can not be completely eliminated. Especially in the arid and windy areas of our country, this kind of intense wear is more prominent.
Four, cold start dry friction
The research of American General Motors Company shows that when the automobile engine stops for 4 hours, all the lubricating oil on the friction interface will flow back to the lubricating oil tank. At this time, when the engine is started, dry friction caused by periodic lubrication loss will occur in a short time, which will cause serious abnormal wear of the engine because the oil pump has no time to pump the lubricating oil to all lubricating parts. This kind of strong wear is not solved by lubricating oil at all. According to other relevant data, this kind of strong wear accounts for more than 70% of the total engine wear. )
Verbs (short for verbs) wear out normally.
Wear caused by normal engine operation. After understanding the causes of engine wear, the role of lubricating oil in reducing engine wear is clear. At the same time, it is obvious that it is very important to use anti-wear protection products to prolong the service life and maintain the engine.
In addition, although additives such as antiwear agents, viscosity index improvers, detergent dispersants, rust inhibitors, antioxidants, etc. Are more or less present in all high-efficiency lubricating oils. It should be emphasized that the above additives are not equivalent to professional automobile maintenance products. In practical use, people often want to obtain maintenance products with excellent comprehensive performance, which requires the selection of various additives and the use of compounding technology and configuration technology to manufacture compound products with wide applicability. It is not easy to develop a good compound formula, and the use of additives mainly depends on the experimental results. Secondly, there is a synergistic effect between different additives, which may be positive or negative. Therefore, to develop a good automobile maintenance product, it is necessary to fully understand the performance of various basic additives, and to go through a large number of laboratory and road vehicle tests. This is also the reason why the composite basic additives of professional automobile maintenance products are completely different from the basic additives, and the basic additives are only used as additives for various oil products.
This is only one aspect of the automobile complex structural system-the maintenance of lubrication system. Cleaning and maintenance of fuel system, cooling system, automatic transmission system and power steering system are also very important, because only when they are perfectly combined can a real car be formed, and only when all systems work well at the same time can the excellent driving performance of the car be guaranteed.
In actual driving, the fuel tank, oil circuit, carburetor, nozzle, combustion chamber, piston crown and valve of the fuel system will inevitably produce impurities in the form of carbon deposition due to the accumulation of time, which will lead to engine failures such as poor start, unstable idle speed, poor acceleration, stall, jitter and knock. In the cooling system, with the normal use of coolant, its function will gradually deteriorate, and the formation of impurities and harmful reactions will seriously reduce the efficiency of the system, leading to the damage of pumps, radiators, water pipes and seals. This will seriously lead to cylinder liner infiltration and engine scrapping. At the same time, the cooling system plays a cooling role in power steering system, pneumatic control system and automatic transmission. If the cooling effect is not good, it will affect the normal work of other systems, which is the most easily overlooked place. According to the statistics of American Highway Department, 40% of the car failures in expressway are related to the cooling system. In the automatic transmission system, the polluted automatic transmission oil will cause the transmission to work rudely and shift gears difficultly. However, if there is a steering problem and the steering wheel wobbles, it is caused by harmful impurities, paint films and other deposits in the power steering system.
Solutions to the above series of problems
Clean up first.
There is a simple reason. The existence of deposits such as carbon deposit, dirt and harmful impurities will seriously affect the efficiency of the system. It's a bit like people need to brush their teeth every day and take a bath often.
The next step is maintenance. According to scientific maintenance methods and technical specifications, select good products to maintain vehicles regularly or at a fixed mileage.
When it comes to maintenance, we must understand the current popular cleaning without disassembly. So, what is cleaning without disassembly? Cleaning without disassembly means cleaning the deposits such as carbon deposit and sludge in the engine (including fuel and lubrication system), automatic transmission system and power steering system without disassembling the car.
Modern automobile engines are assembled in a constant temperature and ultra-static environment according to strict technological requirements, and the assembly conditions can not be met by all repair shops. In addition, with the wide application of EFI technology, sensing technology and computer control technology, the electronic degree of automobiles is getting higher and higher, and the equipment is becoming more and more complicated. Inadvertent disassembly and maintenance will damage sensitive equipment and cause unexpected losses. This is also the reason why the performance will decrease every time the engine is disassembled.
The growth process of automobile maintenance industry is almost synchronous with the development of automobile. With the maturity of the automobile industry in the 1950s, it gradually rose and became a huge industry today. In the United States, more than 70% of automobile maintenance enterprises are quick repair shops that apply automobile maintenance products, providing a wide range of maintenance services, and only under special circumstances will they go to the enterprise's repair shops. Nowadays, the maintenance consciousness of automobile consumers has been greatly improved, so it is imperative to understand automobile maintenance comprehensively, objectively and scientifically.
How to maintain the engine?
1. Pay attention to the use of running-in period. This is the basis of prolonging the service life of the engine. Whether the engine is new or overhauled, it must be run-in according to the instructions before it can be put into normal operation.
2. Be sure to check the fasteners. Or the diesel engine is affected by vibration, impact and uneven load during use, and the bolts and nuts are easy to loosen. Check the adjusting bolts in various parts carefully to avoid damaging parts due to looseness. Valve clearance, valve timing, fuel supply advance angle, fuel injection pressure and ignition timing should be checked and adjusted in time to ensure that the engine is always in good technical condition, thus saving fuel and prolonging service life.
3. Keep oil, water, gas and body clean. If the fuel is impure, it will lead to the wear of precision fittings, increase the fit clearance, lead to oil leakage and dripping, reduce the power supply pressure, increase the clearance, and even cause serious faults such as oil circuit blockage and shaft burning. If the air contains a lot of dust, it will accelerate the wear of cylinder liner, piston and piston ring; If the cooling water is not pure, it will increase the scaling of the cooling system, hinder the heat dissipation of the engine, worsen the lubrication conditions, and cause serious wear and tear of parts. If the appearance of the car body is not clean, it will corrode the car body and shorten its service life.
Make sure there is enough oil, water and air. If the supply of gasoline and air gas is not timely or interrupted, there will be problems such as starting difficulty, poor combustion, power decline and engine failure. If the oil supply is insufficient or interrupted, the engine will be poorly lubricated, the parts will be seriously worn, and even the tiles will be burned. Insufficient cooling water, too high machine temperature, decreased power, increased wear and tear, and shortened service life.
5. Be diligent in observation and inspection, troubleshoot in time, maintain the engine regularly, and keep the machine in good technical condition.
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