What are the diagnostic parameters of cylinder seal?

Section 2 Detection of Cylinder Sealability The cylinder sealability is related to the technical conditions of cylinder block, cylinder head, cylinder gasket, piston, piston ring, intake and exhaust valves and other parts. During the use of the engine, due to the wear, ablation, coking or carbon deposition of these parts, the cylinder tightness decreases, the engine power decreases, the fuel consumption rate increases, and the service life is greatly shortened. Cylinder tightness is an important parameter to characterize the technical condition of the engine. Under the condition of no disassembly, the common methods to detect the tightness of the cylinder are: measuring the compression pressure of the cylinder; Measure crankcase blowby; Measure the air leakage or air leakage rate of the cylinder; Measure the negative pressure of intake pipe, etc. In the on-board inspection, as long as one or two of them are carried out, the tightness of the cylinder can be determined. First, the detection of cylinder compression pressure When the piston reaches the compression top dead center, the cylinder compression pressure can indicate the tightness of the cylinder. Detection methods include gas cylinder pressure gauge detection and gas cylinder pressure tester detection. 1. Check the cylinder pressure gauge with the cylinder pressure gauge, as shown in Figure 2-3. Using cylinder pressure gauge to detect cylinder compression pressure (hereinafter referred to as cylinder pressure) has the advantages of low price, light instrument, strong practicability and convenient detection, and is widely used in automobile maintenance enterprises.