Technician A says that many bearings also have a thin overlay of babbitt. Technician B says that bearings should have spread and crush to keep them from spinning when the crankshaft rotates. Which technician is correct?

In this case, both technicians are correct

Explanation:

There are several bearings with a thin overlay of babbitt. Also, technician B is also correct because the bearings is expected to be stagnant when the crankshaft rotates, and this can be achieved by ensuring that these bearings have spread and crush capable of ensuring they do not spin during operation.