There are seven factors that affect the air tightness of the cylinder, mainly including cylinder wear, piston ring damage, piston wear, valve seat damage, valve guide wear, cylinder gasket damage, valve clearance and other issues.
What are the commonly used diagnostic methods? It mainly measures cylinder pressure, crankcase blow-by, cylinder air leakage and air leakage rate, intake pipe vacuum, and vibration measurement of abnormal noise caused by excessive wear of the cylinder piston set. The wear metal in the crankcase is the particle content. The determination.
For the measurement of cylinder compression pressure, it is mainly the pressure at the end of the four-stroke engine compression. Due to factors such as cylinder pressure and oil viscosity and cylinder-piston group matching, the adjustment of the valve mechanism is correct, the sealing of the cylinder gasket and other factors, so when measuring the pressure of the engine cylinder, the cylinder-piston group can be diagnosed. If the sealing of the piston ring, valve, and cylinder gasket is good, the clearance of the valve must be proper.
Our testing methods for engine tightness mainly include first blowing out the dirt around the spark plug with compressed air, and then removing the spark plug. For gasoline, the secondary high-voltage line of the ignition system should be pulled out for reliable grounding. This is to prevent electric shock and fire. Insert the tapered rubber plug of the special cylinder pressure gauge into the spark plug hole of the cylinder. It must be righted and pressed tightly. For the special throttle valve, it must be placed in the full In the open position, the starter must drive the corresponding crankshaft to rotate. If the needle indicator of the pressure gauge is maintained to a certain extent, the rotation must be stopped after the maximum pressure is read. Finally, remove the pressure gauge and write down the reading.
