diff --git a/ckanext/harvest/helpers.py b/ckanext/harvest/helpers.py
index 4c7dfb6..b372064 100644
--- a/ckanext/harvest/helpers.py
+++ b/ckanext/harvest/helpers.py
@@ -18,7 +18,7 @@ def package_list_for_source(source_id):
     '''
     limit = 20
     page = int(request.params.get('page', 1))
-    fq = 'harvest_source_id:{0}'.format(source_id)
+    fq = 'harvest_source_id:"{0}"'.format(source_id)
     search_dict = {
         'fq' : fq,
         'rows': limit,
diff --git a/ckanext/harvest/logic/action/update.py b/ckanext/harvest/logic/action/update.py
index 5af1e10..d647674 100644
--- a/ckanext/harvest/logic/action/update.py
+++ b/ckanext/harvest/logic/action/update.py
@@ -156,7 +156,7 @@ def harvest_source_index_clear(context,data_dict):
     harvest_source_id = source.id
 
     conn = make_connection()
-    query = ''' +%s:%s +site_id:"%s" ''' % ('harvest_source_id', harvest_source_id,
+    query = ''' +%s:"%s" +site_id:"%s" ''' % ('harvest_source_id', harvest_source_id,
                                             config.get('ckan.site_id'))
     try:
         conn.delete_query(query)