diff --git a/pillarsdk/projects.py b/pillarsdk/projects.py
index 6863dfd..601e840 100644
--- a/pillarsdk/projects.py
+++ b/pillarsdk/projects.py
@@ -51,19 +51,16 @@ class Project(List, Find, Create, Post, Update, Delete, Replace):
         api = api or self.api
         attributes = attributes or self.to_dict()
         etag = attributes['_etag']
-        attributes.pop('_id')
-        attributes.pop('_etag')
-        attributes.pop('_created', None)
-        attributes.pop('_updated', None)
-        attributes.pop('_links', None)
-        attributes.pop('_deleted', None)
         attributes.pop('allowed_methods', None)
+
         # Strip embedded image file properties and revert to ObjectId
         for prop in ['picture_square', 'picture_header']:
             if prop in attributes and type(attributes[prop]) is dict:
                 attributes[prop] = attributes[prop]['_id']
         # Remove None attributes
         attributes = utils.remove_none_attributes(attributes)
+        attributes = utils.remove_private_keys(attributes)
+
         url = utils.join_url(self.path, str(self['_id']))
         headers = utils.merge_dict(
             self.http_headers(),