Dongfeng Nissan Yida
2. Check the spark plug to see whether the model is correct and whether the electrode gap is between 0.7 and 0.9. Observing the combustion situation at the same time is helpful to judge the adjustment of carburetor. It is strongly recommended to choose high-quality imported spark plugs with correct calorific value, and beware of counterfeiting.
3. Measure the compression ratio. If there is no cylinder gauge, cover the spark plug hole with a piece of tissue paper. If the paper is sucked violently when starting, it is ok. Pay attention. You can make your own air nozzle and install it on the spark plug hole, and use the pump to check the air leakage.
4. Check the valve timing. Sometimes a wrong tooth in the installation of valve camshaft will not affect the operation of crankshaft, but it will cause great changes in valve timing, which plays a vital role in the performance of 4T engine. The modification of some 4T engines can start from here, which is the range of advanced modification, but the original factory settings have good adaptability from low speed to high speed, so it is recommended not to tamper with them generally. Otherwise, it will be self-defeating.
5, high voltage line hanging fire test. Do everything, see if it's a high-voltage line, an ignition coil or a spark plug. In addition, check whether the installation sequence of high-voltage lines in each cylinder is correct from the igniter, and never mix them up. Generally speaking, the wiring of the primary coil should be connected according to the wiring direction, not forcibly. The secondary coil high-voltage line generally controls which side of the' straight 4' of a two-cylinder locomotive has one coil 1 and 4, and the other coils 2 and 3; V4 is 1, 3, 2, 4. If you think the connection is a bit awkward, it may be wrong.
6. Oil inspection. It is best to remove the oil tank and use the container to force the oil delivery, because there is a possibility that the switch of the negative pressure oil tank will fail. In addition, see if the interface glue between carburetor and engine leaks.
7. Check the mixing ratio of carburetor. First of all, it is necessary to clean the carburetor thoroughly. If you twist the throttle quickly (as fast as possible), the engine speed will rise slowly, and there are guns and black smoke in the exhaust pipe, indicating that the mixture ratio is too strong. If it is found that there is a flameout trend or flameout, the carburetor has reverse injection and tempering, indicating that the mixture ratio is too thin. Check whether the oil level is correct. Whether the setting of mixing ratio screw is correct. The mixing ratio adjustment screw of carburetor in kinhin, Japan is usually set between 1 3/4 and 2 1/4 (the 4T model is of equal vacuum type), for example, CB400SF is 1 7/8, depending on different models. You can directly set the screw to the bottom and rotate it for 2 turns, and then adjust it according to the situation.
8. Ignition timing. Regular inspection requires timing lights, which is not cheap. Fortunately, if the car has not been changed, this advance angle is generally not wrong. The above reasons will only be considered if all other conditions are ruled out, the exhaust port is still on fire or the carburetor is backfired. Besides, there is something wrong with the igniter. Checking this gadget requires a special oscilloscope, which most people don't have. Better borrow someone else's.
9. Otherwise, try to use some starting fluids that are more flammable than gasoline.
Let's talk about the method of electric starting first. In fact, every car is different, and the starting method is somewhat different. The most convincing thing should be the owner of each car. For the 4T car, let's talk about the ideal starting mode and state of the cold car first.
For ordinary cars, don't twist the throttle to pull the shock absorber (in fact, for 4T cars, the throttle and shock absorber are both wrong names, and people who don't understand it are easy to make mistakes. The scientific name should be air throttle valve, start the thickening valve, but it will continue to go wrong here, as everyone is used to calling it). If the performance is good, you should be able to start it in three seconds without even pulling the damper. For sports cars, the method is different. You must pull the air door. After the motor is running, you must twist the throttle at the right time to start smoothly. The reason is that the valve overlap angle of sports car is relatively large, and the compression force is insufficient at low speed, so the throttle valve should be adjusted with the rebound of pressure wave. This leads to the starting method of the engine with insufficient cylinder compression: when starting, after pulling the throttle, press the start button and twist the throttle repeatedly at the fastest speed.
Then there is how to push the cart, which is a tiring job. From the above, we know that the engine needs a minimum speed of 200rpm to start, so we should calculate how fast your car should run in what gear. You can't push it in low gear, but you can't reach the speed in high gear, usually in third gear. Grab the clutch, pose, and then sprint 100 meters. When the speed is similar, slowly release the clutch. Pay attention to the speed after the clutch is completely released. At this time, you are probably wondering why you don't adjust the brakes or change some bearings. If all goes well, you should feel that the car is starting to pant. Don't stop at this time, otherwise all previous efforts will be in vain! When the sound is even, grab the clutch and cooperate with the throttle, and the speed will be OK. After proficiency, you can drive a short distance.
If it is indeed the same model and brand oil, it is unlikely to be the problem of the oil itself.
SAE 10W40 engine oil can be used normally at-10 degree. If the temperature is low, it is recommended to use 100% all synthetic engine oil with 5W50, but the price is more expensive. Engine oil is the blood of the engine. Never make do with or use fake and inferior products.
In addition, if your engine is dirty and there is serious sludge inside, it will also increase the internal resistance. If the single coil of the starter motor is short-circuited and open-circuited, the motor power will be affected. In a word, what I said earlier is the possibility of fault analysis, which provides some reference materials for everyone to explore the truth of the engine. It is impossible to cure all diseases, and the specific situation needs specific analysis. For a sick car, the more you know, the more helpful it is.