Lineweights for a project are set globally using Line Weight settings for each scale, and applying them to Object Styles.
But sometimes a particular view may not appear the way you want it to.
To overcome this problem you should NOT change these global settings.
Fixing you problem may create a whole lot of new problems for other views.
By all means, if you believe the global settings should be changed, suggest changes to the rest of the team. But don't make changes without their agreement.
As an alternative there are various methods to change line weights in a particular view.
Use Visibility/Graphic Overrides:
Change category, or subcategory, projection and/or cut linestyles.
Use Override Host Layers.
This will change how system families like floors, walls, roofs and ceilings will display when cut.
Silhouette Style:
This is accessed via the Graphic Display Options of a view.
Either via Properties or the Shadows icon at bottom of view window.
It allows control over the line weight used on edges which have nothing behind them of sections and elevations.
Linework Tool:
This allows you to change the way individual lines display.
It is time consuming so NOT recommended unless there is no other alternative.
When you use it a blue dot appears at each end of the line you have changed. You can drag those blue dots to change the extents of the change you are making. But you can only REDUCE it, it can't be bigger than the underlying line you are changing.
Also note that changing a line brings it to the front - any part hidden by objects in front will now display. But you can use the blue dots to make it look like it is still behind.