diff --git a/notebook/services/sessions/handlers.py b/notebook/services/sessions/handlers.py
index 987255d9c..7282c339c 100644
--- a/notebook/services/sessions/handlers.py
+++ b/notebook/services/sessions/handlers.py
@@ -106,16 +106,17 @@ class SessionHandler(APIHandler):
             if notebook.get('path') is not None:
                 changes['path'] = notebook['path']
         if 'kernel' in model:
-            if model['kernel'].get('name') is not None:
-                kernel_name = model['kernel']['name']
-                kernel_id = yield sm.start_kernel_for_session(
-                    session_id, kernel_name=kernel_name, path=before['notebook']['path'])
-                changes['kernel_id'] = kernel_id
+            # Kernel id takes precedence over name.
             if model['kernel'].get('id') is not None:
                 kernel_id = model['kernel']['id']
                 if kernel_id not in km:
                     raise web.HTTPError(400, "No such kernel: %s" % kernel_id)
                 changes['kernel_id'] = kernel_id
+            elif model['kernel'].get('name') is not None:
+                kernel_name = model['kernel']['name']
+                kernel_id = yield sm.start_kernel_for_session(
+                    session_id, kernel_name=kernel_name, path=before['notebook']['path'])
+                changes['kernel_id'] = kernel_id
 
         yield gen.maybe_future(sm.update_session(session_id, **changes))
         model = yield gen.maybe_future(sm.get_session(session_id=session_id))
diff --git a/notebook/services/sessions/tests/test_sessions_api.py b/notebook/services/sessions/tests/test_sessions_api.py
index e82452281..c0cda3b15 100644
--- a/notebook/services/sessions/tests/test_sessions_api.py
+++ b/notebook/services/sessions/tests/test_sessions_api.py
@@ -53,7 +53,8 @@ class SessionAPI(object):
         return self._req('PATCH', id, body)
 
     def modify_kernel_id(self, id, kernel_id):
-        body = json.dumps({'kernel': {'id': kernel_id}})
+        # Also send a dummy name to show that id takes precedence.
+        body = json.dumps({'kernel': {'id': kernel_id, 'name': 'foo'}})
         return self._req('PATCH', id, body)
 
     def delete(self, id):