Disassembly of the cylinder block was discussed in the article - "Disassembly of the cylinder block"
After disassembling the cylinder block, it is necessary to determine the possibility of further use of the cylinder block, crankshaft and piston group.
Checking the cylinder block
The non-flatness of the seating surface of the cylinder block is allowed no more than 0.03 mm.
Sanding is not allowed.
Checking should be carried out according to the diagram in Figure 1.
Determining the cylinder diameter
The distance X from the axis of the holes (1) to the seating surface of the cylinder block determines the group of cylinder diameters (see the table for details).
Label (2) corresponds to cylinder #1, and label (3) corresponds to cylinder #4 (see figure 2).
Before checking, the crankshaft main bearing caps must be installed by installing the #1 cap on the flywheel side.
After that, we tighten the bolts of the crankshaft main bearing caps in the order shown in Figure 3.
We measure the diameters and remove the crankshaft main bearing caps.
Diameters (X1 Figure 4) of the crankshaft bearings are marked by drilling in the area above the oil filter (Figure 4 (B) in the direction of the arrow).
The position (X2) of the holes in relation to the seating surface of the cylinder block determines the diameter of the crankshaft bearings.
The crankshaft lies in the cylinder block on five bearings.
Thrust half rings that regulate the axial clearance are installed on support No. 3.
Permissible parameters of the crankshaft:
Axial play of the crankshaft with new thrust half rings - 0.045 - 0.252 mm;
Axial play of the crankshaft with run-in thrust half rings - 0.027 - 0.054 mm.
Diameter clearance between the main journals of the crankshaft and bearings, mm - 0.027 - 0.054 mm.
Measuring the diameters of the crankshaft journals in Figure 5.
Cylinder diameters
Main bearing support diameters
The size of the diameters of the main bearing supports in the cylinder block is given in table 2.
The size of the main bearing shells is given in table 3.
Diameters of the holes of the main bearing supports in the cylinder block
Main bearing shell dimensions
Size groups according to the diameter of the main journals
Size groups according to the diameter of the connecting rod journals:
When measuring, the result is taken as the minimum diameter along the perimeter of the neck.
Crankshaft marking
Location of the factory marking and marking information in Figure 6.
Labels carry the following information:
- 1 - size groups according to the diameter of the main journals;
- 2 - size groups according to the diameter of the main journal No. 1 from the flywheel side;
- 3 - size groups according to the diameter of the main journal No. 5 from the flywheel side;
- 4 - size groups according to the diameter of the connecting rod journals;
- 5 - size groups according to the diameter of the connecting rod journal No. 1 on the flywheel side.