2.3.13. Dismantling and assembly of pistons and rods

Sizes of pistons and cylinders
The sizes do not include a graphite covering (thickness of 0,02 mm).
The graphite covering is used up over time.


Check of a thermal gap of piston rings
Drive a ring from above, at right angle to a cylinder wall, to the lower opening of the cylinder, at distance about 15 mm from its edge. For this purpose use the piston without rings.


Check of a gap of piston rings on height

Fig. 2.134. Check of a gap of a piston ring on height



Before check clear a ring flute of the piston.


Check of pistons
Measure approximately in 10 mm from bottom edge, at right angle to an axis of a piston finger.
As much as possible tolerance from the nominal size of 0,04 mm

Check of diameter of the cylinder
Carry out measurements a cross on a cross in three places in the cross direction A and the longitudinal direction B (fig. 2.135).

Fig. 2.135. Scheme of check of diameter of the cylinder


As much as possible tolerance from the nominal size: 0,08 mm.

Adjusting provision of an insert of the bearing

Fig. 2.136. Adjusting provision of an insert of the bearing


Bearing 1 insert with an oil opening for a rod (fig. 2.136).
Bearing 2 insert without oil opening for a cover of a rod (fig. 2.136).
Enclose inserts of bearings in a rod and a cover of a rod in the middle.
The size A have to be identical at the left and on the right.