Cylinder liner is one of the important component parts of the combustion chamber, the outer edge of the cylinder liner should be done with the cleaning surface and the body mounting holes, especially supporting shoulder on the body and the cylinder liner supporting shoulder clean. The lower portion of the cylinder liner with water blocking rings have to clean and smooth. Application of pressure required equipment pushed. But individual owners of multi-purpose repair hammering method knock, knocking debris falling into the process often supporting shoulder, he shall be positioned on the cylinder annulus will enter again blowing compressed air on the body mounting hole net, otherwise the cylinder Set After the machine mechanical loads increase, resulting in partial mill or on / off cylinder 0 accidents. Mounting ring with dirty water blocking ring will cause water leakage or water blocking laps sheared. Water blocking ring coated with a little grease should be installed, to prevent trimming. Set after the cylinder body, the amount of protrusion should be checked on the end face (each type has specific requirements), the projecting amount is too small, the cylinder head gasket pressure is not dense, easy to leakage and blow-by gas; too big will the fracturing cylinder head gasket, Can not be ignored.

Some optional piston cylinder and multi-cylinder engine is divided into 34 groups according to the deviation, the packet number hit the top end surface of the piston and cylinder, only the piston and the cylinder matched with the group to ensure the cylinder gap requirements. Many maintenance workers only know the standard piston and cylinder, pay attention to the size of the group number, after the destruction of the assembly complex relationship.

At present, some single-cylinder machine and individual models (eg B4125J diesel) packet size is not accurate. Piston pin and piston pin bore are grouped according to manufacturing variations, piston pin seat hole packet number of useful label hit the top surface of the piston, is also useful color applied to the inside of the outer edge of the housing bore, the piston pin packet number more paint applied within Round ends only with the group number to match, in order to ensure cooperation relationship. But some models (such as B4125J) only one group number. The same engine mounted piston mass difference can not exceed the specified value (eg 4125G6, B4125J etc. not exceed 10g), each several mass of the piston (the actual mass percentile and deciles two digits) is playing in the top surface of the piston, if tolerance should be the mass balance. There cylinder gap (the difference between the maximum transverse diameter of the cylinder bore and piston skirt) concept can not be sloppy.

Tapered oval piston and piston skirt skirt is of course the underlying transverse direction (the vertical direction of the piston pin hole) and the difference between the size of the cylinder bore. However, some of the piston (such as B4125J diesel) is drum shaped skirt, not the maximum size of its lower end, the skirt should be measured in the middle. Mentioned above refers to the new cylinder liner, cylinder if worn but not exceeding the allowable limit, the measured gap to take a position on how the cylinders shall determine, worth exploring.