diff --git a/cime_config/buildexe b/cime_config/buildexe
index c8664d705..44f0437e3 100755
--- a/cime_config/buildexe
+++ b/cime_config/buildexe
@@ -64,10 +64,10 @@ def _main_func():
         skip_mediator = False
 
     if ocn_model == 'mom':
-        gmake_args += "USE_FMS=TRUE"
+        gmake_args += " USE_FMS=TRUE"
 
     if link_libs is not None:
-        gmake_args += 'USER_SLIBS="{}"'.format(link_libs)
+        gmake_args += ' USER_SLIBS="{}"'.format(link_libs)
 
     comp_classes = case.get_values("COMP_CLASSES")
     for comp in comp_classes: