The engine crankshaft is a five-bearing, cast iron with spheroidal graphite. The bearings are made in the body of the cylinder block crankcase in the form of plain bearings. Lubricating grooves are made in the upper liners of the main bearings. Counterweights are made on the cheeks of the shaft, cast together with the shafts. The crankshafts are divided into three dimensional groups, marked with colored paint marks (yellow, green and purple) on the cheeks in the area of the main journals. Regrinding of the crankshaft bearings with their reduction to the repair dimensions of the 1st and 2nd classes is allowed.
Diameter of crankshaft main journals of N62 engines:
Bearing bed 1.*
yellow mark:
- nominal size - 69.974 - 69.980 mm;
- size 1st class - 69.724 - 69.730 mm (reduction by 0.25 mm);
- size 2nd class - 69.474 - 69.480 mm (decrease by 0.50 mm).
green mark:
- nominal size - 69.967 - 69.972 mm;
- size 1st class - 69.717 - 69.723 mm (reduction by 0.25 mm);
- size 2nd class - 69.467 - 69.473 mm (decrease by 0.50 mm).
purple mark:
- nominal size - 69.961 - 69.966 mm;
- size 1st class - 69.711 - 69.716 mm (reduction by 0.25 mm);
- size 2nd class - 69.461 - 69.466 mm (decrease by 0.50 mm).
Bearing bed 2 – 5.
yellow mark:
- nominal size - 69.984 - 69.990 mm;
- size 1st class - 69.734 - 69.740 mm (reduction by 0.25 mm);
- size 2nd class - 69.484 - 69.490 mm (decrease by 0.50 mm).
green mark:
- nominal size - 69.977 - 69.983 mm;
- size 1st class - 69.727 - 69.733 mm (reduction by 0.25 mm);
- size 2nd class - 69.477 - 69.483 mm (decrease by 0.50 mm).
purple mark:
- nominal size - 69.971 - 69.976 mm;
- size 1st class - 69.721 - 69.726 mm (reduction by 0.25 mm);
- size 2nd class - 69.471 - 69.476 mm (decrease by 0.50 mm).
Crankshaft axial clearance:
- nominal - 0.080 mm;
- maximum - 0.246 mm.
Radial clearance of crankshaft main bearings:
- nominal - 0.024 mm;
- maximum - 0.052 mm.
Thrust bearing width:
- nominal - 28.0 mm;
- size 1st class - 28.2 mm;
- size 2nd class - 28.4 mm.
The maximum permissible runout on the middle main journal, with support on journals 1 and 5, is no more than 0.15 mm.
Diameter of connecting rod journals of crankshaft of engines "N62":
- nominal size - 54.00 mm;
- size 1st class - 53.75 mm;
- size 2nd class - 53.50 mm.
With execution tolerance from -0.009 mm to -0.025 mm.
Radial clearance of crankshaft connecting rod bearings (between the liners and the crankshaft journal):
- nominal - 0.028 mm;
- maximum - 0.070 mm.
The maximum permissible ovality of the surfaces of the main and connecting rod journals is no more than 0.003 mm.
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