Final answer:
The technician should check for rod bending when the bearings from one rod are worn along the parting lines.
Step-by-step explanation:
When examining the old connecting rod bearings from an engine, if the bearings from one rod are worn along the parting lines, the technician should check carefully for rod bending. Rod bending can cause uneven wear along the parting lines of the bearings. This can occur due to misalignment or excessive stress on the rod, resulting in an out-of-round shape and uneven wear on the bearings.