Cylinder inspection of automotive parts

How to analyze the engine cylinder seal test results.

There are seven factors affecting the cylinder sealing performance, mainly including cylinder wear, piston ring damage, piston wear, valve seat damage, valve guide wear, cylinder head gasket damage, valve clearance and other aspects.

What are the commonly used diagnostic methods? There are mainly measurement of cylinder pressure, crankcase xenon gas volume, cylinder air leakage and air leakage rate, intake pipe vacuum degree, and abnormal vibration of cylinder piston group due to excessive wear. The wear metal in the crankcase is the particle content. Determination.

For the measurement of the cylinder compression pressure, it is mainly the pressure at the end of the four-stroke engine compression. Due to the pressure of the cylinder, the viscosity of the oil and the cylinder piston set, the adjustment of the valve train is correct, the sealing of the cylinder head and other factors, so when measuring the pressure of the engine cylinder, the cylinder piston can be diagnosed. In the case of sealing, if the piston ring, valve, and cylinder head gasket are well sealed, the clearance of the valve must be appropriate.

In the engine sealing test method, we mainly use compressed air to blow off the dirt around the spark plug, and then remove the spark plug. For gasoline, the ignition high-voltage line 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 measured by the cylinder. It must be pressed and tightened. For the special throttle, it must be placed in the whole. In the open position, the starter should drive the corresponding crankshaft to rotate. If the gauge indication of the pressure gauge has a certain hold, the final pressure reading must have a certain stop rotation. Finally, remove the pressure gauge and record the reading.