A small number of cylinders do not work is one of the common faults of the engine, which directly affects the engine and power of Baotou North Heavy Duty Truck engine. How to quickly and accurately judge and eliminate the fault?
After starting the engine, gradually increase the throttle, if the speed from low speed to high speed process in the exhaust muffler can hear the rhythm of the “sudden burst,” sound, and with the increase of speed “motivation, process, process sound frequency is increased, it can be considered as the engine a few cylinders do not work.
Determine the number of cylinders do not work, we should first replace the spark plug, and then check whether the high pressure drop off. If there is no loss, high voltage short circuit testing method applied to determine which cylinder does not work, namely the spark plug short-circuit screwdriver at the same time to observe the change of the engine speed. If a cylinder spark plug short-circuit, the engine speed decreased significantly, indicating that the cylinder is working properly; such as a slight decline in speed, the cylinder is not working properly; such as no change in speed, indicating that the cylinder does not work. Check ignition system, it is best to use the ignition oscilloscope, in the absence of oscilloscope, the following methods can be used to check:
1, if a cylinder does not work, should unplug the cylinder pressure line, at a distance of 5 7mm around the spark plug, observe whether there is a fire, if the fire, or the other end of the line from the distributor Jack pulled out a little, to see whether to jump the fire line jack. Such as jumping fire, then the leakage line.
2, if there are two cylinders do not work, should be pulled out of the cylinder of the two cylinder line, from the spark plug of about 5 – 7mm, to check whether the fire. If the jump is fire, and the engine speed is not changed, it may be two cylinder line plug or two cylinder spark plug are not working. Such as the removal of the two cylinder cents are not jumping fire, or a jump of a fire does not jump the fire, should be checked according to a cylinder does not work inspection methods. If you do not work on the two cylinder of the distributor next to the socket adjacent to the first pull out a cylinder of cents, about 5mm from the spark plug to check the fire situation. If there is no fire or fire is weak, it should be divided back, pull the other cylinder line, check the fire jump, such as fire or fire is weak, then the two lines at the same time to block jump fire, and the two line from the gas cylinder distance is far and near, even if the root line is close, which jumped fire, it can be sure that the electric jack channeling for the two cylinder line.
3, if the high voltage to the spark plug spark and spark strong, Baotou North heavy truck parts spark plug good, should check whether the engine mechanical failure caused by.
4, the electronic ignition of the engine, must use the oscilloscope, can not use the above method of fire test. In addition, if Baotou beiben accessories carbon spark plug serious, may be caused by excessive wear of the engine, you must first rule out mechanical failure for further examination.