Cylinder block
Cylinder diameter, mm:
- class A: 79.000–79.010;
- class B: 79.010–79.020;
- class C: 79.020–79.030;
- class D: 79.030–79.040;
- class E: 79.040–79.050.
When repairing the cylinder block, it is necessary to honing the cylinders for the increased diameters of the pistons of the repair dimensions (by 0.4 and 0.8 mm) and taking into account the provision of a gap of 0.05–0.07 mm between the piston and the cylinder, which is measured in the same way as on the 2101 engine.
Piston
Scheme of removing metal from the piston of the engine 21011 to adjust its mass
Diameter of pistons of various classes, measured at a distance of 52.4 mm from the piston crown, mm:
- class A: 78.940–78.950;
- class B: 78.950–78.960;
- class C: 78.960–78.970;
- class D: 78.970–78.980;
- class E: 78.980–78.990.
Until 1988, piston diameters were 0.01 mm smaller than indicated.
The increase for the repair dimensions of the pistons is 0.4 and 0.8 mm. Until 1986, oversized pistons were produced with an increase in diameter of 0.4 and 0.7 mm.
Also, as on the 2101 engine, the pistons of one engine should not differ in mass by more than 2.5 g. When adjusting the mass, metal removal should not exceed 4.5 mm in depth relative to the nominal piston height (59.4 mm), and in width should be limited to a diameter of 70.5 mm.
On the bottom of the piston there is a recess with a diameter of 55 mm and a depth of 1.9 mm.
When pressing the piston pin into the connecting rod, use tool 02.7853.9500 instead of A.60325.
When installing pistons in cylinders, use the set of bushings 02.7854.9500, similar to the set of bushings A.60604 (see fig. V clause 9 of subsection 3.5).
Set 02. 7854.9500 contains three bushings: one for standard size pistons, two for repair size pistons (enlarged by 0.4 and 0.8 mm).