Problem: When you change scales in a view the section marks disappear.
This is a setting in the properties of the section mark. This is intended to prevent HUGE section marks at scales like 1:1000 or 1/64"=1'-0". Here's how to change that parameter:
1. Click on section mark
2. Open Properties
3. change the 'Hide at scales coarser than' parameter
This applies to one section annotation at a time.