Cylinders — wear check

Theoretically, the new cylinder is perfectly round. The operation of the piston results in wall wear at right angles to the piston pins due to side loading. This wear takes place mainly in this section of the cylinder due to friction against the piston rings.

The first signs of wear can be seen by feeling the step directly near the top of the cylinder where the top piston ring goes. If there is no such step, then the cylinder wear is negligible and there are no losses due to lack of compression or excessive oil consumption due to wear or damage to the piston rings or pistons.

If you have a special cylinder micrometer, measure the diameter of the cylinder in the plane below the top edge of the cylinder block, and the diameter of the hole in the bottom of the cylinder in the same plane.

If any of the cylinders has noticeable scratches or grooves, it also requires reboring. This phenomenon usually indicates damage to the piston or rings. If at least one of the cylinders needs to be bored, it is necessary to perform this operation for all cylinders and install new pistons and piston rings oversized.