What might occur if an open-end wrench is used with too large of an opening for the job?

Using an open-end wrench with too large of an opening can lead to the jaws of the wrench becoming sprung. When the wrench is applied to a nut or bolt that is smaller than the opening of the wrench, the tool does not fit snugly around the fastener, which can cause the jaws to flex or spread apart. This improper fit means that the force applied during tightening or loosening is not evenly distributed, increasing the likelihood of deforming the wrench itself. Over time, this can compromise the reliability and effectiveness of the tool, rendering it less useful for future jobs.

While using a wrench that is too large could lead to other issues, such as difficulty applying the proper torque, the direct consequence of having sprung jaws is a significant concern, as it ultimately affects the tool's capabilities and safety.