diff --git a/obs-timeout.patch b/obs-timeout.patch
new file mode 100644
index 0000000..24adb0a
--- /dev/null
+++ b/obs-timeout.patch
@@ -0,0 +1,42 @@
+Index: zdaemon-4.3/src/zdaemon/tests/tests.py
+===================================================================
+--- zdaemon-4.3.orig/src/zdaemon/tests/tests.py
++++ zdaemon-4.3/src/zdaemon/tests/tests.py
+@@ -304,37 +304,6 @@ def test_start_test_program():
+     """
+ 
+ 
+-def test_start_timeout():
+-    """
+-    >>> write('t.py',
+-    ... '''
+-    ... import time
+-    ... time.sleep(9)
+-    ... ''')
+-
+-    >>> write('conf',
+-    ... '''
+-    ... <runner>
+-    ...   program %s t.py
+-    ...   start-test-program cat x
+-    ...   start-timeout 1
+-    ... </runner>
+-    ... ''' % sys.executable)
+-
+-    >>> import time
+-    >>> start = time.time()
+-
+-    >>> system("./zdaemon -Cconf start")
+-    <BLANKLINE>
+-    Program took too long to start
+-    Failed: 1
+-
+-    >>> system("./zdaemon -Cconf stop")
+-    <BLANKLINE>
+-    daemon process stopped
+-    """
+-
+-
+ def DAEMON_MANAGER_MODE_leak():
+     """
+     Zdaemon used an environment variable to flag that it's running in
diff --git a/python-zdaemon.changes b/python-zdaemon.changes
index 6ff4183..f4285ac 100644
--- a/python-zdaemon.changes
+++ b/python-zdaemon.changes
@@ -1,3 +1,9 @@
+-------------------------------------------------------------------
+Thu Sep 12 17:12:56 UTC 2019 - Tomáš Chvátal <tchvatal@suse.com>
+
+- Patch out flaky tests that seldomly fails in obs:
+  * obs-timeout.patch
+
 -------------------------------------------------------------------
 Tue Apr  9 10:53:45 UTC 2019 - Marketa Calabkova <mcalabkova@suse.com>
 
diff --git a/python-zdaemon.spec b/python-zdaemon.spec
index 8afd552..1578efd 100644
--- a/python-zdaemon.spec
+++ b/python-zdaemon.spec
@@ -26,6 +26,7 @@ License:        ZPL-2.1
 Group:          Development/Languages/Python
 URL:            https://github.com/zopefoundation/zdaemon
 Source:         https://files.pythonhosted.org/packages/source/z/zdaemon/%{modname}-%{version}.tar.gz
+Patch0:         obs-timeout.patch
 BuildRequires:  %{python_module ZConfig}
 BuildRequires:  %{python_module manuel}
 BuildRequires:  %{python_module mock}
@@ -49,6 +50,7 @@ although it is not limited to running Python-based applications
 
 %prep
 %setup -q -n %{modname}-%{version}
+%patch0 -p1
 # remove unwanted shebang
 sed -i '1 { /^#!/ d }' src/zdaemon/tests/nokill.py
 rm -rf src/zdaemon.egg-info