Piston to cylinder selection

Estimated clearance between piston and cylinder (for new parts) equal to 0.025-0.045 mm. It is determined by measuring parts and is provided by installing pistons of the same class as the cylinders. Maximum allowable clearance (when parts are worn) - 0.15 mm.

If a used engine has a clearance greater than 0.15 mm, then it is necessary to reselect the pistons to the cylinders so that the clearance is as close as possible to the calculated one.

Pistons of classes A, C, E are supplied as spare parts. These classes are sufficient for selecting a piston for any cylinder during engine repair, since pistons and cylinders are divided into classes with a small overlap in size. For example, class B and D cylinders can be fitted with a class C piston.