Check that the nut securing the lever is fully tightened.
Check that the face of the lever that operates the valve is bent through a full 90 degrees in relation to the mounting face. If not, remove the lever and correct the bend in a vice.
Check that the nut securing the lever is fully tightened.
Check that the face of the lever that operates the valve is bent through a full 90 degrees in relation to the mounting face. If not, remove the lever and correct the bend in a vice.