To delete an action:

1. Go to the Collection tab where you want to delete the Action. Make sure Author Mode is turned on.
2. Click the Wrench icon in the top-center of the page above the Collection's view.
3. Select Actions and then select the name of the Action that you want to delete.
   
4. Click on Delete, the Delete Action dialog will appear.
   
   
5. When asked to confirm click Yes .

You are not allowed to delete any of the default Actions, Create, Update or Delete.