Figure 4-48. Measuring of Main and Connecting Rod Bearing Journals.

TM 55-1930-208-24

(14) When the runout on the adjacent journals is in oppositedirections, the sum must not exceed .003 inch total

indicator reading. When the runout on the adjacent journals of the four and six cylinder crankshaft is in the

same direction, the difference must not exceed .003 inch total indicator reading. When high spots of runout on

the adjacent journals of the three cylinder crankshaft are at right angles to each other, the sum must not exceed

.004 inch total indicator reading, or .002 inch on each journal. If the runout limit is greater, the crankshaft must

be replaced.

(15) Measure all of the main connecting rod bearing journals as shown ill figure 4-48. Measure journals at several

places on the circumference so that taper, out-of-round and bearing clearances can be determined. If the

crankshaft is worn so that the maximum journal-to-bearing shell clearance (with new shells) exceeds .0044 inch,

the crankshaft must be replaced. Measurements of the crankshaft should be accurate to the nearest .0002 inch.

Also, if the journal taper of a used crankshaft exceeds .0015 inch or the out-of-round is greater than .001 inch

the crankshaft must be replaced.

Figure 4-48. Measuring of Main and Connecting Rod Bearing Journals.

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