2. Checking the runout of the crankshaft.
A) Lay the crankshaft on the prisms.
b) Using a dial indicator, check the beating of the crankshaft on the central main journal.
- Maximum runout - 0.05 mm
If the runout is greater than the maximum allowable, replace the crankshaft.
3. Check the connecting rod and main journals.
A) Using a micrometer, measure the diameter of each connecting rod and main journal in two mutually perpendicular planes, as shown in the figure.
Crankpin diameter:
Nominal size - 54.940 - 54.955 mm
Repair size:
- (0,25) - 54.690 - 54.705 mm
- (0,50) - 54.440 - 54.455 mm
- (0,75) - 54.190 - 54.205 mm
Diameter of main journals:
Shakes #1, 2, 4, 5:
Nominal size - 66.937 - 66.955 mm
Repair size:
- (0,25) 66.687 - 66.705 mm
- (0,50) 66.437-66.455 mm
- (0,75) 66.187-66.205 mm
Neck #3:
Nominal size - 66.920 - 66.938 mm
Repair size:
- (0,25) 66.670-66.688 mm
- (0,50) 66.420 - 66.438 mm
- (0,75) 66.170-66.188 mm
The maximum amount of neck wear is 0.05 mm
If the diameters are outside the specified limits, regrind or replace the crankshaft.
b) Check the connecting rod and main journals for out-of-roundness as shown in the previous figure.
- Maximum out-of-roundness - 0.03 mm
If the out-of-roundness is greater than the maximum, replace the crankshaft.