Clearing a Body Merge undoes the merge. You will need to re-merge the Body Merge before generating a solution.

To clear a body merge, right-click the Body Merge object and select Clear from the menu. The name of the merged body is replaced by the names of the bodies that were previously selected for the merge.

The bodies in a cleared Body Merge do not necessarily revert to the properties they had before the merge. Clearing also affects scoping and meshing. For more information, see How Body Merge Affects Body Attributes, Scoping, and Meshing.